Relevant bibliographies by topics / AprX gene

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Academic literature on the topic 'AprX gene'

Author: Grafiati
Published: 9 March 2023
Last updated: 11 March 2023

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Journal articles on the topic "AprX gene"

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Liao, Ching-Hsing, and Daniel E. McCallus. "Biochemical and Genetic Characterization of an Extracellular Protease from Pseudomonas fluorescensCY091." Applied and Environmental Microbiology 64, no. 3 (March 1, 1998): 914–21. http://dx.doi.org/10.1128/aem.64.3.914-921.1998.

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ABSTRACT Pseudomonas fluorescens CY091 cultures produce an extracellular protease with an estimated molecular mass of 50 kDa. Production of this enzyme (designated AprX) was observed in media containing CaCl2 or SrCl2 but not in media containing ZnCl2, MgCl2, or MnCl2. The requirement of Ca2+ (or Sr2+) for enzyme production was concentration dependent, and the optimal concentration for production was determined to be 0.35 mM. Following ammonium sulfate precipitation and ion-exchange chromatography, the AprX in the culture supernatant was purified to near electrophoretic homogeneity. Over 20% of the enzyme activity was retained in the AprX sample which had been heated in boiling water for 10 min, indicating that the enzyme is highly resistant to heat inactivation. The enzyme activity was almost completely inhibited in the presence of 1 mM 1,10-phenanthroline, but only 30% of the activity was inhibited in the presence of 1 mM EGTA. The gene encoding AprX was cloned from the genome of P. fluorescens CY091 by isolating cosmid clones capable of restoring the protease production in a nonproteolytic mutant of strain CY091. The genomic region of strain CY091 containing the aprX gene was located within a 7.3-kb DNA fragment. Analysis of the complete nucleotide sequence of this 7.3-kb fragment revealed the presence of a cluster of genes required for the production of extracellular AprX inP. fluorescens and Escherichia coli. The AprX protein showed 50 to 60% identity in amino acid sequence to the related proteases produced by Pseudomonas aeruginosa andErwinia chrysanthemi. Two conserved sequence domains possibly associated with Ca2+ and Zn2+ binding were identified. Immediately adjacent to the aprXstructural gene, a gene (inh) encoding a putative protease inhibitor and three genes (aprD, aprE, andaprF), possibly required for the transport of AprX, were also identified. The organization of the gene cluster involved in the synthesis and secretion of AprX in P. fluorescens CY091 appears to be somewhat different from that previously demonstrated inP. aeruginosa and E. chrysanthemi.
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Longhi, Rosana De, Samera Rafaela Bruzaroski, Josiane Ito Eleodoro, Regina Celia Poli-Frederico, Rafael Fagnani, Agostinho Ludovico, and Elsa Helena Walter de Santana. "Presence of aprX gene in Pseudomonas spp. from refrigerated raw milk and their proteolytic ability." Semina: Ciências Agrárias 41, no. 4 (May 13, 2020): 1421. http://dx.doi.org/10.5433/1679-0359.2020v41n4p1421.

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This study aimed to determine the frequency of Pseudomonas fluorescens, P. putida, and P. aeruginosa in refrigerated raw milk; their proteolytic potential; and your association with the aprX gene. Of the 173 isolates confirmed as belonging to Pseudomonas spp., 37% were P. fluorescens, 25.4% P. putida, and none belongs to P. aeruginosa. The aprX gene was distributed proportionally between P. putida (68%) and P. fluorescens (75%), but it was not associated with low or high proteolytic potential in both species. P. putida (16) and P. fluorescens (14) isolates with no aprX gene identified also had proteolytic potential. Considering the synthesis of proteases other than AprX by the isolates under study, we concluded that P. fluorescens and P. putida represented 62.4% of the Pseudomonas genus, with high probability of having the aprX gene and proteolytic potential. However, there was no association between the deteriorating potential with the presence of the aprX gene.
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Zarei, Mehdi, Hooriyeh Mohammadpour, Darioush Gharibi, and Mahdi Pourmahdi Borujeni. "Identification of Pseudomonas jessenii and Pseudomonas gessardii as the most proteolytic Pseudomonas isolates in Iranian raw milk and their impact on stability of sterilized milk during storage." Journal of Dairy Research 87, no. 3 (August 2020): 368–74. http://dx.doi.org/10.1017/s0022029920000709.

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AbstractIdentification of the most proteolytic Pseudomonas strains that can produce heat-resistant proteases and contribute to the Ultra High Temperature (UHT) milk destabilization is of great interest. In the present study, among the 146 Pseudomonas isolates that encoded the aprX gene, five isolates with the highest proteolytic activity were selected and identified based on 16S rRNA, rpoD and gyrB gene sequences data. The identification results were confirmed by phylogenetic analysis based on multilocus sequence analysis and identified the representative isolates as P. jessenii (two isolates) and P. gessardii (three isolates). Casein zymography demonstrated the ability of these species to produce heat-resistant enzymes, AprX, with molecular mass of about 48 kDa during storage at 7° C for 72 h. In sterilized milk samples, the residual activity of AprX caused a considerable enhancement in the degree of protein hydrolysis, non-protein nitrogen and non-casein nitrogen contents of the samples during a two-month storage. This enhancement was slightly higher in samples containing enzyme produced by P. jessenii compared to P. gessardii ones, resulting in earlier onset of sterilized milk destabilization. Hence, this study revealed that P. jessenii and P. gessardii can play a considerable role in deterioration of Iranian commercial long-life milk.
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Teider Junior, Pedro I., José C. Ribeiro Júnior, Eric H. Ossugui, Ronaldo Tamanini, Juliane Ribeiro, Gislaine A. Santos, Amauri A. Alfieri, and Vanerli Beloti. "Pseudomonas spp. and other psychrotrophic microorganisms in inspected and non-inspected Brazilian Minas Frescal cheese: proteolytic, lipolytic and AprX production potential." Pesquisa Veterinária Brasileira 39, no. 10 (October 2019): 807–15. http://dx.doi.org/10.1590/1678-5150-pvb-6037.

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ABSTRACT: The most consumed cheese in Brazil, Minas Frescal cheese (MFC) is highly susceptible to microbial contamination and clandestine production and commercialization can pose a risk to consumer health. The storage of this fresh product under refrigeration, although more appropriate, may favor the growth of spoilage psychrotrophic bacteria. The objective of this study was to quantify and compare Pseudomonas spp. and other psychrotrophic bacteria in inspected and non-inspected MFC samples, evaluate their lipolytic and proteolytic activities and their metalloprotease production potentials. Twenty MFC samples were evaluated: 10 inspected and 10 non-inspected. Counts of psychrotrophic bacteria and Pseudomonas spp., evaluation of the proteolytic and lipolytic potential of the isolates, and identification of potential producers of alkaline metalloprotease (AprX) were assessed. The mean total psychrotrophic counts were 1.07 (±2.18) × 109CFU/g in the inspected samples and 4.5 (±5.86) × 108CFU/g in the non-inspected, with no significant difference (p=0.37). The average score of Pseudomonas spp. was 6.86 (±18.6) × 105 and 2.08 (±3.65) × 106 CFU/g for the inspected and non-inspected MFC samples, respectively, with no significant difference (p=0.1). Pseudomonas spp. represented 0.06% and 0.004% of psychrotrophic bacteria found in inspected and non-inspected MFC samples, respectively. Collectively, 694 psychrotrophic strains and 47Pseudomonas spp. were isolated, of which 59.9% and 68.1% were simultaneously proteolytic and lipolytic, respectively. Of the 470 psychrotrophs isolated from inspected and 224 from non-inspected cheese samples, 5.74% and 2.23% contained aprX, respectively, while 100 and 86.96% of the Pseudomonas spp. isolates in inspected and non-inspected cheese samples contained the gene. The production potential of AprX did not, however, determine the proteolytic activity on plates of these isolates under the conditions evaluated in this study. Of total, 65.63% of the psychrotrophs that contained aprX gene were confirmed as Pseudomonas spp., using genus-specific PCR. Phylogenetic analysis of the 16S rRNA gene of the other psychrotrophs that were potential producers of AprX identified them as Serratia spp. (n=7), Raoultella ornithinolytica (n=1), and Acinetobacter schindleri (n=1) in the inspected samples and Psychrobacter sanguinis (n=1) and Leuconostoc mesenteroides (n=1) in the non-inspected samples. The production conditions of Brazilian MFC of these samples, while meeting the legal determinations, are not sufficient to control Pseudomonas and other spoilage-related psychrotrophs. Thus, stricter hygienic measures are required during the formal production of this type of cheese.
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Maier, Christopher, Katharina Hofmann, Christopher Huptas, Siegfried Scherer, Mareike Wenning, and Genia Lücking. "Simultaneous quantification of the most common and proteolytic Pseudomonas species in raw milk by multiplex qPCR." Applied Microbiology and Biotechnology 105, no. 4 (February 2021): 1693–708. http://dx.doi.org/10.1007/s00253-021-11109-0.

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Abstract The heat-stable peptidase AprX, secreted by psychrotolerant Pseudomonas species in raw milk, is a major cause of destabilization and premature spoilage of ultra-high temperature (UHT) milk and milk products. To enable rapid detection and quantification of seven frequent and proteolytic Pseudomonas species (P. proteolytica, P. gessardii, P. lactis, P. fluorescens, P. protegens, P. lundensis, and P. fragi) in raw milk, we developed two triplex qPCR assays taking into account species-dependent differences in AprX activity. Besides five species-specific hydrolysis probes, targeting the aprX gene, a universal rpoB probe was included in the assay to determine the total Pseudomonas counts. For all six probes, linear regression lines between Cq value and target DNA concentration were obtained in singleplex as well as in multiplex approaches, yielding R2 values of > 0.975 and amplification efficiencies of 85–97%. Moreover, high specificity was determined using genomic DNA of 75 Pseudomonas strains, assigned to 57 species, and 40 other bacterial species as templates in the qPCR. Quantification of the target species and total Pseudomonas counts resulted in linear detection ranges of approx. 103–107 cfu/ml, which correspond well to common Pseudomonas counts in raw milk. Application of the assay using 60 raw milk samples from different dairies showed good agreement of total Pseudomonas counts calculated by qPCR with cell counts derived from cultivation. Furthermore, a remarkably high variability regarding the species composition was observed for each milk sample, whereby P. lundensis and P. proteolytica/P. gessardii were the predominant species detected. Key points • Multiplex qPCR for quantification of seven proteolytic Pseudomonas species and total Pseudomonas counts in raw milk • High specificity and sensitivity via hydrolysis probes against aprX and rpoB • Rapid method to determine Pseudomonas contamination in raw milk and predict spoilage potential
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Costa, Nayara Aparecida da Silva, Rafaela da Silva Rodrigues, Antônio Fernandes de Carvalho, and Solimar Gonçalves Machado. "Proteases e lipases produzidas por Pseudomonas: um desafio na indústria de lácteos." Journal of Engineering and Exact Sciences 8, no. 9 (November 10, 2022): 14900–01. http://dx.doi.org/10.18540/jcecvl8iss9pp14900-01e.

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Pseudomonas spp. são comumente relacionadas com a deterioração de produtos lácteos. Algumas espécies desse gênero, além de se multiplicarem em temperaturas de refrigeração, produzem enzimas hidrolíticas responsáveis pela deterioração do leite e seus derivados. A metaloprotease AprX é uma das proteases produzidas por Pseudomonas. Essa enzima, codificada pelo gene aprX, é resistente ao calor e capaz de manter sua atividade mesmo após tratamentos térmicos comumente utilizados na indústria de laticínios, como pasteurização e tratamento UHT (Ultra-high Temperature), resultando em perdas das características sensoriais e em problemas como a gelificação. Algumas cepas de Pseudomonas também podem produzir enzimas lipolíticas termorresistentes. Essas enzimas catalisam a hidrólise de triacilgliceróis, resultando na liberação de ácidos graxos associados à deterioração de muitos alimentos. Esses ácidos contribuem para o sabor forte, rançoso e de sabão de produtos lácteos. Em vista disso, o objetivo deste trabalho foi destacar, por meio de uma revisão de literatura, os desafios enfrentados pela indústria de lácteos frente às proteases e lipases produzidas pelo gênero Pseudomonas.
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Anderson, L. Meadow, Virginia O. Stockwell, and Joyce E. Loper. "An Extracellular Protease of Pseudomonas fluorescens Inactivates Antibiotics of Pantoea agglomerans." Phytopathology® 94, no. 11 (November 2004): 1228–34. http://dx.doi.org/10.1094/phyto.2004.94.11.1228.

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Pseudomonas fluorescens A506 and Pantoea agglomerans strains Eh252 and C9-1 are biological control agents that suppress fire blight, an important disease of pear and apple caused by the bacterium Erwinia amylovora. Pseudomonas fluorescens strain A506 suppresses disease largely through competitive exclusion of E. amylovora on surfaces of blossoms, the primary infection court, whereas Pantoea agglomerans strains Eh252 and C9-1 produce antibiotics that are toxic to E. amylovora. In this study, an extracellular protease produced by A506 is characterized and evaluated for its capacity to inactivate the antibiotics produced by the strains of Pantoea agglomerans. Activity of the extracellular protease was optimal at pH 9 and inhibited by zinc- or calcium-chelators, indicating that the protease is an alkaline metalloprotease. In an agar plate bioassay, partially purified extracellular protease inactivated the antibiotics mccEh252 and herbicolin O, which are produced by Pantoea agglomerans strains Eh252 and C9-1, respectively. Derivatives of A506 deficient in extracellular protease production were obtained by transposon mutagenesis, and the aprX gene encoding the protease was cloned and sequenced. Strain A506 inactivated mccEh252 and herbicolin O in agar plate bioassays, whereas the aprX mutant did not inactivate the antibiotics. Both A506 and the aprX mutant were insensitive to antibiosis by C9-1 and Eh252; thus, the protease was not required to protect A506 from antibiosis. These data highlight a previously unknown role of the extracellular protease produced by Pseudomonas fluorescens A506 in interactions among plant-associated microbes.
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Ribeiro Júnior, José C., Pedro I. Teider Junior, André L. M. Oliveira, Edson A. Rios, Ronaldo Tamanini, and Vanerli Beloti. "Proteolytic and lipolytic potential of Pseudomonas spp. from goat and bovine raw milk." Pesquisa Veterinária Brasileira 38, no. 8 (August 2018): 1577–83. http://dx.doi.org/10.1590/1678-5150-pvb-5645.

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ABSTRACT: Pseudomonas, the main genus of gram-negative microorganisms isolated from milk, is psychrotrophic, biofilm-forming, and thermo-resistant deteriorating enzyme producers. The aim of this study was to quantify Pseudomonas spp. in goat’s and cow’s milk produced in the Paraná state, Brazil, to evaluate the deteriorating activity of the isolates at mesophilic and psychrotrophic conditions and to identify, at the species level, the isolates with alkaline metalloprotease (aprX gene) production potential. Microbiological, biochemical and molecular methods were used for isolating, confirming and identifying of isolates. The mean counts were 1.6 (±6.3)x104 and 0.89(±3)x102 CFU/mL for goat and bovine milk samples, respectively, immediately after milking. Of the Pseudomonas colonies isolated from goat milk (n=60), 91.7% showed proteolytic potential when incubated at 35°C/48 h and 80% at 7°C/10 days, and lipolytic potential was observed in 95% of the isolates incubated in mesophilic and 78.3% at refrigeration conditions. From the isolates of bovine milk (n=20), 35% showed proteolytic activity only when incubated at 35°C/48 h, and lipolytic potential was observed in 25% of the isolates incubated at 7°C/10d and 35°C/48h. It was observed that 83.3% and 25% of the isolates genetically confirmed as Pseudomonas spp. of goat and bovine milk showed the potential for alkaline metalloprotease production, with the species P. azotoformans, P. koreensis, P. gessardii, P. monteilii and P. lurida being the most frequent in goat milk and P. aeruginosa the only species identified in cow milk.
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Okrent, Rachel A., Anne B. Halgren, Mark D. Azevedo, Jeff H. Chang, Dallice I. Mills, Maciej Maselko, Donald J. Armstrong, Gary M. Banowetz, and Kristin M. Trippe. "Negative regulation of germination-arrest factor production in Pseudomonas fluorescens WH6 by a putative extracytoplasmic function sigma factor." Microbiology 160, no. 11 (November 1, 2014): 2432–42. http://dx.doi.org/10.1099/mic.0.080317-0.

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Pseudomonas fluorescens WH6 secretes a germination-arrest factor (GAF) that we have identified previously as 4-formylaminooxyvinylglycine. GAF irreversibly inhibits germination of the seeds of numerous grassy weeds and selectively inhibits growth of the bacterial plant pathogen Erwinia amylovora. WH6-3, a mutant that has lost the ability to produce GAF, contains a Tn5 insertion in prtR, a gene that has been described previously in some strains of P. fluorescens as encoding a transmembrane regulator. As in these other pseudomonads, in WH6, prtR occurs immediately downstream of prtI, which encodes a protein homologous to extracytoplasmic function (ECF) sigma factors. These two genes have been proposed to function as a dicistronic operon. In this study, we demonstrated that deletion of prtI in WT WH6 had no effect on GAF production. However, deletion of prtI in the WH6-3 mutant overcame the effects of the Tn5 insertion in prtR and restored GAF production in the resulting double mutant. Complementation of the double prtIR mutant with prtI suppressed GAF production. This overall pattern of prtIR regulation was also observed for the activity of an AprX protease. Furthermore, reverse transcription quantitative real-time PCR analysis demonstrated that alterations in GAF production were mirrored by changes in the transcription of two putative GAF biosynthetic genes. Thus, we concluded that PrtI exerted a negative regulatory effect on GAF production, although the mechanism has not yet been determined. In addition, evidence was obtained that the transcription of prtI and prtR in WH6 may be more complex than predicted by existing models.
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Schumann, R. R., C. J. Kirschning, A. Unbehaun, H. P. Aberle, H. P. Knope, N. Lamping, R. J. Ulevitch, and F. Herrmann. "The lipopolysaccharide-binding protein is a secretory class 1 acute-phase protein whose gene is transcriptionally activated by APRF/STAT/3 and other cytokine-inducible nuclear proteins." Molecular and Cellular Biology 16, no. 7 (July 1996): 3490–503. http://dx.doi.org/10.1128/mcb.16.7.3490.

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Acute-phase reactants (APRs) are proteins synthesized in the liver following induction by interleukin-1 (IL-1), IL-6, and glucocorticoids, involving transcriptional gene activation. Lipopolysaccharide-binding protein (LBP) is a recently identified hepatic secretory protein potentially involved in the pathogenesis of sepsis, capable of binding the bacterial cell wall product endotoxin and directing it to its cellular receptor, CD14. In order to examine the transcriptional induction mechanisms by which the LBP gene is activated, we have investigated the regulation of expression of its mRNA in vitro and in vivo as well as the organization of 5' upstream regulatory DNA sequences. We show that induction of LBP expression is transcriptionally regulated and is dependent on stimulation with IL-1beta, IL-6, and dexamethasone. By definition, LBP thus has to be viewed as a class 1 acute-phase protein and represents the first APR identified which is capable of detecting pathogenic bacteria. Furthermore, cloning of the LBP promoter revealed the presence of regulatory elements, including the common APR promoter motif APRE/STAT-3 (acute-phase response element/signal transducer and activator of transcription 3). Luciferase reporter gene assays utilizing LBP promoter truncation and point mutation variants indicated that transcriptional activation of the LBP gene required a functional APRE/STAT-3 binding site downstream of the transcription start site, as well as an AP-1 and a C/EBP (CCAAT enhancer-binding protein) binding site. Gel retardation and supershift assays confirmed that upon cytokine stimulation APRF/STAT-3 binds to its recognition site, leading to strong activation of the LBP gene. Unraveling of the mechanism of transcriptional activation of the LBP gene, involving three known transcription factors, may contribute to our understanding of the acute-phase response and the pathophysiology of sepsis and septic shock.
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Dissertations / Theses on the topic "AprX gene"

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Decimo, M. "BACTERIAL ENZYMATIC ACTIVITIES AS POTENTIAL MARKERS FOR ASSESSING THE TECHNOLOGICAL PROPERTIES OF (UN)PROCESSED MILK." Doctoral thesis, Università degli Studi di Milano, 2014. http://hdl.handle.net/2434/244558.

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RIASSUNTO I batteri psicrotrofi sono i principali responsabili del deterioramento del latte crudo o termotrattato poiché sono in grado di sintetizzare proteasi e lipasi extracellulari termostabili, causa di formazione di odori e sapori sgradevoli, fenomeni di gelificazione, riduzione delle proprietà schiumogene del latte, perdita di qualità sensoriale e riduzione della shelf-life. Ad oggi, non esiste ancora una sufficiente conoscenza degli specifici pathways proteolitici e lipolitici di questi enzimi termostabili. Inizialmente questo lavoro ha riguardato la caratterizzazione dell’attività enzimatica di 80 ceppi di psicrotrofi isolati da latte crudo. I batteri appartenenti al genere Pseudomonas sono stati i più isolati (78.75%) e Pseudomonas fluorescens è risultata la specie predominante (30.16%); tra le Enterobacteriaceae (21.25%), Serratia marcescens è stata la specie più frequentemente isolata (52.94%). Quarantuno ceppi di psicrotrofi mostravano tutte le attività enzimatiche. Il più alto numero di ceppi positivi a tutte le temperature di incubazione è stato osservato per l’attività lipolitica (59) e, a seguire, proteolitica (31) e lecitinasica; i tratti enzimatici variavano tra i ceppi di Pseudomonas e Enterobacteriaceae ed erano marcatamente influenzati dalla temperature di incubazione, essendo 30 °C quella ottimale. Il gene aprX è stato ritrovato in 19 ceppi di Pseudomonas ed è risultato esser diffuso tra i ceppi di P. fluorescens (15 su18). La seconda parte della ricerca è stata focalizzata sulla valutazione della produzione di composti organici volatili (VOCs) e del rilascio di acidi grassi liberi (FFAs) da ceppi di batteri psicrotrofi. Diverse specie del genere Pseudomonas e il ceppo Serratia marcescens hanno mostrato profili di VOCs complessi e dipendenti dal ceppo batterico inoculato in campioni di latte UHT, durante le differenti condizioni di incubazione. In particolare, sono stati identificati 56 VOCs appartenenti a aldeidi, chetoni, acidi grassi, alcoli, composti solforati e idrocarburi. Generalmente, il numero di VOCs tendeva ad incrementare con il progredire del tempo di incubazione, sia nel latte controllo non inoculato sia nei campioni di latte contaminati. Tra i VOCs rilevati, alcune molecole sono state individuate solo quando il latte era contaminato da uno specifico ceppo microbico. Nel dettaglio, 3-metilbutan-2-olo, 3-metilesan-2-olo, pentan-1-olo e 3,3-dimetilesano sono stati rilevati solo a seguito dello sviluppo di P. fragi. P. rhodesiae è stata l’unica specie a produrre pentano-2,3-dione, eptano e 3-metilesano, mentre l’esano è stato rilasciato solo in campioni di latte contaminati con P. fluorescens. La maggior produzione di composti solforati e alcoli è stata individuata nello spazio di testa del latte contaminato con P. mosselii e P. fragi, rispettivamente. Lo sviluppo e l’attività di P. rhodesiae e S. marcescens sono risultati associati ad un più alto numero di acidi grassi e chetoni mentre P. fluorescens ha mostrato la più scarsa produzione di composti volatili. Alcuni VOCs come 3-metilbutan-1-olo, 2-metilpropan-1-olo, 3-idrossibutan-2-one, butano-2,3-dione, acido butanoico ed acido esanoico potrebbero perciò rappresentare potenziali marker per il riconoscimento dell’attività enzimatica di batteri psicrotrofi e per la precoce individuazione del deterioramento del prodotto. Per quanto riguarda il rilascio di FFAs, diverse quantità di questi composti sono state rilasciate dai batteri psicrotrofi appartenenti a specie diverse e alla stessa specie conseguentemente alla diversa capacità di produrre lipasi. Gli acidi palmitico (16:0), oleico (18:1) e linoleico (18:2) sono risultati i più presenti tra gli acidi grassi saturi, monoinsaturi e polinsaturi. P. fluorescens PS73 e P. fluorescens PS81 sono state le specie che hanno prodotto la maggior quantità di FFAs, a 24 h e 4 giorni di incubazione, rispettivamente. Al contrario, H. alvei PS57 e P. fragi PS55 hanno rilasciato la minor quantità di FFAs ad entrambi i tempi di incubazione. Le lipasi dei ceppi di psicrotrofi hanno mostrato una specificità variabile nei riguardi degli esteri degli acidi grassi con diversa lunghezza della catena carboniosa. P. fragi PS55, P. putida PS17, P. fluorescens PS14 and P. fulva PS10 sono risultate le specie più attive nell’idrolisi dei trigliceridi. La lipasi del ceppo di P. rhodesiae PS62 ha mostrato la più scarsa capacità idrolitica verso tutti i trigliceridi testati. Infine, è stata effettuata la caratterizzazione proteomica di proteasi extracellulari di ceppi di P. fluorescens. Una proteasi termostabile di circa 45 kDa è stata individuata su casein zymogram gel in ciascun surnatante dei ceppi batterici selezionati. L’estratto enzimatico del ceppo P. fluorescens PS19, concentrato per ultrafiltrazione (10 kDa), ha mostrato un’elevata attività proteolitica e due ulteriori bande proteolitiche di circa 15 e 25 kDa. I risultati delle analisi nLC/MS/MS dopo digestione sia in gel che in solution hanno evidenziato che la proteasi di 45 kDa corrisponde ad una AprX metalloproteasi di P. fluorescens (acc. no. C9WKP6, UniProt). La proteasi di 15 kDa è stata riconosciuta come un frammento della stessa AprX metalloproteasi, mentre la proteasi di 25 kDa non ha mostrato nessuna omologia con alcuna delle proteine note di Pseudomonas. La caratterizzazione tramite LC/MS del profilo peptidico generato dall’azione delle proteasi termostabili dello stesso ceppo sulle frazioni caseiniche del latte è in corso di studio. In generale, questo studio fornisce ulteriori conoscenze per la lo studio delle attività enzimatiche di batteri psicrotrofi nel latte.
ABSTRACT Psychrotrophic bacteria are responsible for the highest spoilage of unprocessed or heated milk during storage because of their capacity to synthesize thermostable extracellular proteases and lipases. The activities of these enzymes lead to formation of off-odours/flavours, gelation of milk, lowering of milk foaming properties, loss of sensory quality and shortening of the shelf life. To date, still little is known about the specific proteolytic and lipolytic pathways of these thermostable enzymes. Initially we evaluated the enzymatic traits of 80 raw milk-associated psychrotrophic strains. Among psychrotrophic isolates, Pseudomonas were the most commonly occurring contaminants (78.75%) being Pseudomonas fluorescens the predominant isolated species (30.16 %), along with Enterobacteriaceae (21.25%), primarily Serratia marcescens (52.94 %). Forty-one of the psychrotrophic strains were positive for all the enzymatic activities. The highest number of positive strains for all incubation temperatures was found for the lipolytic activity (59), followed by proteolytic (31) and lecithinase (28) activities. The enzymatic traits varied among the Pseudomonas and Enterobacteriaceae strains and were markedly influenced by incubation temperature being 30 °C the optimal one. The aprX gene was detected in 19 out of 80 psychrotrohic strains and it resulted widespread among P. fluorescens strains (15 out of 18). The second part of the research was focused on the evaluation of spoilage potential of psychrotrophic strains by analyzing the production of volatile organic compounds (VOCs) and the release of free fatty acids (FFAs). From results of SPME-GC/MS analysis, different species of the genus Pseudomonas and Serratia marcescens produced a complex and strain-dependent VOCs profiles in UHT milk samples at different storage and time conditions. Fifty-six VOCs belonging to 7 chemical groups (aldehydes, ketones, fatty acids, esters, alcohols, sulphur compounds and hydrocarbons) were identified. Generally, the VOCs went to increase during the storage time both in the control and contaminated milk samples, some compounds being detected only in the latter samples. Compounds such as 3-methylbutan-2-ol, 3-methylhexan-2-ol, pentan-1-ol and 3,3-dimethylhexane were detectable only for P. fragi. P. rhodesiae was the only species producing pentane-2,3-dione, heptane and 3-methylhexane while hexane was released only by P. fluorescens. P. mosselii and P. fragi produced the highest number of sulphur compounds and alcohols, respectively. The highest number of FFAs and ketons was detected in the headspace of milk samples contaminated by P. rhodesiae and S. marcescens. P. fluorescens provided the lowest development of VOCs. 3-methylbutan-1-ol, 2 methylpropan-1-ol, 3-hydroxybutan-2-one, butane-2,3-dione and butanoic and hexanoic acids could be regarded as potential markers of psycrotrophic contamination useful for the early detection of milk bacterial spoilage. Regarding the release of FFAs, different quantities of these compounds have been released from milk fat by tested bacteria, between and within species, in relation to diverse capacity for production of lipolytic enzymes. Palmitic (16:0), oleic (18:1) and linoleic (18:2) acids levels were found to be the highest among the SFAs, MUFAs and PUFAs, respectively. P. fluorescens PS73 and P. fluorescens PS81 were the major FFAs producers, at 24 h and 4 days of incubation, respectively while H. alvei PS57 and P. fragi PS55 were the less active in lipid breakdown at both the incubation conditions. Lipases from psychrotrophic strains showed a variable range of specificity toward fatty acid esters with different fatty acid chain lengths, being P. fragi PS55, P. putida PS17, P. fluorescens PS14 and P. fulva PS10 the more active to hydrolyse triglycerides. Lipase from P. rhodesiae PS62 showed the highest hydrolytic resistance toward all tested fatty acid triglycerides. Finally, proteomic characterization of extracellular proteases of P. fluorescens strains has been performed. One thermostable protease of approximately 45 kDa was detected in each of the cell-free supernatant of the selected strains on a casein zymogram gel. After concentration by ultrafiltration (10 kDa), the protease extract of P. fluorescens PS19 showed a high proteolytic activity and two additional proteolytic bands with molecular masses of approximately 15 and 25 kDa on casein zymography. This extract was subjected to proteomic characterization by nLC/MS/MS analysis of both in gel and in solution digestion. Results showed the protease of 45 kDa to correspond to P. fluorescens AprX metalloprotease (acc. no. C9WKP6, UniProt). In addition, the same results leaded to recognize the 15 kDa protease as a fragment of this AprX metalloprotease. On the contrary, the 25 kDa protease showed no homology to any known protein of Pseudomonas spp. The characterization by LC/MS of the peptides profile generated by the action of thermostable proteases of the same strain on milk caseins is still under investigation. Overall, this study provides a better understanding of the enzymatic activities of psychrotrophic bacteria in milk.
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Nahar, Nusrat. "Characterisation of gene expression and virulence factors in Actinobacillus pleuropneumoniae." Thesis, Griffith University, 2023. http://hdl.handle.net/10072/421340.

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Actinobacillus pleuropneumoniae is a Gram-negative bacterium causing the highly infectious disease porcine pleuropneumonia and is responsible for global financial losses to the swine industry every year. Though the virulence of A. pleuropneumoniae is complex and multifactorial, Apx toxins (ApxI-III) are the major contributing factors that causes lung lesions in pigs. Although vaccines are available to prevent A. pleuropneumoniae infections, they do not give complete protection and typically give protection against the serovars used to prepare the vaccine. Thus, a thorough understanding of gene expression and virulence factors is required to develop broadly protective pleuropneumonia vaccines. This thesis first investigated a novel pathway to prevent and treat pleuropneumonia infection by blocking the interaction between Apx toxins and the host cells. To determine the specific ligands bound by each Apx toxin, glycan array analysis using purified Apx toxins (ApxI-III, both the active and inactive forms e.g. ApxCA and ApxA) was carried out. Expressing both with and without ApxC allowed an assessment of whether this activation is required for interaction with the host glycan receptor. Significant work was needed to optimise overexpression and purification of Apx toxins. Glycan array analysis demonstrated that both ApxI and ApxII toxins bound to very similar glycan structures, such as gangliosides and Lewis antigens. Binding of Apx toxins occurred irrespective of activation by the cognate acyltransferase, ApxC. Interestingly, glycan binding was not observed for the ApxIII toxin, indicating that interaction of this toxin with its already characterised host cell receptor, the CD18 subunit of β2 integrin, likely does not occur via glycan interactions. In recent years, systems known as phasevarions – for phase-variable regulons – have been described in multiple host-adapted bacterial pathogens. Phasevarions result from the rapid and reversible expression of genes encoding cytoplasmic DNA methyltransferases. This results in variable expression of these methyltransferases in a population, with variable genome wide methylation differences within a bacterial population resulting in differential expression of multiple genes via epigenetic mechanisms. In all described cases, phasevarions control expression of current and putative vaccine candidates. The study in Chapters 4 and 5 characterised the phase-variable Type I and Type III R-M systems identified in A. pleuropneumoniae. A study of the distribution of both systems using 210 whole genome sequences demonstrated that the Type I R-M system is present in almost all serovars of A. pleuropneumoniae, whereas different phase-variable Type III mod genes showed colocalisation with specific serovars of A. pleuropneumoniae. This study also demonstrated that individual strains of A. pleuropneumoniae could encode both phase-variable Type I and Type III R-M systems, a phenomenon never before observed. In Chapter 4, phase-variable expression of the Type I R-M system was demonstrated using two prototype strains with a combination of semi-quantitative RT-PCR and a locus specific FAM-labelled PCR assay. The work carried out here also developed a method by which locked strains could be generated that only express a single HsdS variant. Characterisation of the Type III mod genes in Chapter 5 revealed the presence of two distinct phase-variable Type III methyltransferases, modP (which exists in four variants, designted modP1 to modP4) and modQ in A. pleuropneumoniae. The serovar-specific distribution of each of these new mod genes was further confirmed using a second strain collection, comprising 265 strains from the Australian national culture collection. This study demonstrated that these Type III methyltransferases are phase-variable, and that each variant methylates a different DNA target sequence (established using a combination of Pacific Biosciences Single- Molecule, Real-Time (SMRT) sequencing and Oxford Nanopore sequencing). This methylome analysis demonstrated the presence of the first phase-variable cytosine-specific Type III DNA methyltransferase discovered in bacteria. Analysis of changes in gene expression and phenotype influenced by phase variation of each Type III methyltransferase showed that each distinct variant regulates different phasevarions, and has a unique influence on bacterial phenotype, such as antibiotic resistance (modP2), biofilm formation (modP1) and growth rate (modP1). In summary, this thesis has taken the first step to both treating and preventing disease caused by A. pleuropneumoniae by characterising the exact host receptors bound by the major virulence factors ApxI and ApxII and will allow the development of new treatment strategies that can block the interaction between Apx toxins and their cellular receptors. This would allow for more effective treatments and negate the use of antibiotics for the treatment of porcine pleuropneumonia. The characterisation of the phase-variable Type I and Type III DNA methyltransferases described in this study has begun to define the stably expressed antigenic repertoire of A. pleuropneumoniae. This will direct and inform the development of rationally designed vaccines to prevent disease caused by this major veterinary pathogen.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
Institute for Glycomics
Science, Environment, Engineering and Technology
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Martins, Maurilio Lopes. "Diversidade de bactérias psicrotróficas proteolíticas de leite e presença do gene que codifica metaloprotease alcalina." Universidade Federal de Viçosa, 2003. http://www.locus.ufv.br/handle/123456789/10665.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico
A diversidade genética entre 113 culturas de bactérias psicrotróficas proteolíticas isoladas de amostras de leite cru granelizado foi avaliada utilizando- se a técnica de RAPD. Foi constatada uma grande diversidade genética entre os isolados, indicando fontes de contaminação diversas. A presença do gene apr, que codifica metaloproteases termorresistentes, foi avaliada por PCR em 26 culturas controle e em 133 isolados psicrotróficos proteolíticos de leite cru resfriado e granelizado. Detectou-se a presença do amplificado do gene apr apenas nas culturas de referência Serratia marcescens ATCC 8100, Pseudomonas fluorescens ATCC 13525 e estirpes de P. aeruginosa ATCC 15442 e ATCC 27853. A presença do gene apr foi detectada na mistura de DNA dos isolados psicrotróficos proteolíticos que apresentaram características fenotípicas de espécies do gênero Pseudomonas, quais sejam, Gram-negativas, não fermentadoras, catalase e oxidase positivas. Os demais isolados Gram-negativos e os Gram-positivos, embora tenham apresentado atividade proteolítica, não apresentaram o amplificado do gene apr. A técnica de PCR permitiu identificar a presença de população acima de 10 5 UFC/mL de P. fluorescens inoculada em leite desnatado reconstituído após a extração do DNA total das bactérias. Entretanto, quando amostras de leite pasteurizado inoculado com populações variando de 10 5 a 10 8 UFC/mL foram analisadas por PCR, sem a etapa de extração do DNA total, o limite de detecção foi de 10 8 UFC/mL.
The genetic diversity of 113 cultures of proteolytic psychrotrophic bacteria isolated from raw milk collected from cooling tanks was analyzed by RAPD. A great genetic diversity was detected among these isolates indicating different sources of contamination. The presence of the apr gene, which codes a heat- resistant metalloprotease, was assessed by PCR in 26 type strains and in 136 proteolytic psychrotrophic bacteria isolated from raw milk. The presence of the apr gene was only detected in Serratia marcescens ATCC 8100, Pseudomonas fluorescens ATCC 13525 and, strains of P. aeruginosa ATCC 15442 and ATCC 27853. The apr gene was detected in total DNA extracted from proteolytic psychrotrophics that showed phenotypic characteristics belonging to Pseudomonads such as Gram-negative, non-fermentative, positive-catalase and positive-oxidase. The apr gene was not detected in the other Gram-negative and Gram-positive isolates studied although they have displayed proteolysis. The PCR technique identified the presence of Pseudomonas fluorescens when total DNA was extracted from skim milk previously inoculated with a bacterial population containing 10 5 CFU/mL. However, the detection limit of apr gene without the DNA extraction step was 10 8 CFU/mL in pasteurized milk.
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Ahearn, Kelly Patricia. "Analysis of genes that regulate flowering and branch initiation in the shoot apex of Nicotiana tabacum and Arabidopsis /." view abstract or download file of text, 2000. http://wwwlib.umi.com/cr/uoregon/fullcit?p9963440.

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Thesis (Ph. D.)--University of Oregon, 2000.
Typescript. Includes vita and abstract. Includes bibliographical references (leaves 50-54). Also available for download via the World Wide Web; free to University of Oregon users. Address: http://wwwlib.umi.com/cr/uoregon/fullcit?p9963440.
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Shin, Seung-Geuk. "Microarray Analysis of Differential Expression of Genes in Shoot Apex and Young Leaf of English Ivy (Hedera helix L. cv. Goldheart)." Bowling Green State University / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1273946268.

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Blonski, Michel. "Se nettoyer à Rome (IIème s. av. J.-C. – IIème s. apr. J.-C.) : pratiques et enjeux." Thesis, Paris 4, 2012. http://www.theses.fr/2012PA040008.

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On étudie ici comment les Romains de la fin de la République et du début de l’Empire envisagent les opérations de nettoyage corporel. En suivant plusieurs questions pratiques (de quoi se nettoie-t-on ? dans quel but ? où le fait-on, avec quels moyens et comment ?) et en se fondant sur des analyses anthropologiques, archéologiques et lexicologiques, on délimite les domaines dans lesquels les Romains rangent les catégories du sale, du soin corporel et de la juste présentation de soi. Le vocabulaire de la saleté, en particulier, permet de circonscrire un ensemble varié de réalités indésirables : il n’y a pas « une » mais « des » saletés – tout est fonction de contextes – et le lexique reflète cette diversité.La justification de la propreté, au contraire, se fonde sur des prescriptions morales remarquables par leur permanence et leur cohérence tout au long de la période. La propreté doit être entendue comme la traduction concrète de la notion plus large de soin ; et réciproquement, la saleté traduit celle de négligence. Par conséquent, être un bon citoyen, et au-delà, un être humain véritable, cela passe par la propreté – avec une insistance telle qu’elle fait de cet état un marqueur de reconnaissance sociale. Plus on est propre et « brillant », plus on se situe en haut des hiérarchies civiques. Ces prescriptions morales aboutissent à l’émergence de cette réalité bien romaine qu’est le balneum : le lieu privilégié de l’entretien de ce modèle civique, au croisement entre univers moraux, cosmétiques et médicaux. Elles sont appuyées par un ensemble de techniques spécifiques accordant une place privilégiée au frottement du corps, à l’aide d’huile ou de détergents
This thesis investigates how the Romans envision the operations related to body cleansing at the end of the Republic and the beginning of the Empire. Starting from practical questions – What has to be cleaned? For which purpose? Where does this operation take place? How is it completed? – and leveraging on approaches stemmed from anthropology, archeology and lexicology, we delimitate categories that the Romans link to concepts such as dirtiness, body care or appropriate self-presentation. The terminology of dirtiness, in particular, reveals a manifold set of undesired realities, which nonetheless never appears totally consistent; Depending on the context, there is not one, but several types of dirtiness. On the contrary, the justification of cleanliness is based on a whole range of moral prescriptions which are remarkable by their continuity and their consistency throughout the whole period. It appears that the concept of cleanliness should be understood within the frame of the broader notion of self care. Conversely, dirtiness more generally relates to self negligence. Consequently, being a good citizen, or even living as a genuine human being requires to be clean, to a point where cleanliness becomes a social marker: A clean and “shiny” appearance indicates a higher social status. Hence the growing importance of the balneum as a Roman institution – the place where this model is maintained, across civic, medical and cosmetic representations, through the development of techniques primarily based on body rubbing using oil and detergents
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Young, Duprane Pedaci. "From In Vitro to In Vivo: Control of C-Reactive Protein Gene Expression by Cytokines." Cleveland, Ohio : Case Western Reserve University, 2008. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=case1201365244.

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LIU, GONG-SHE. "Ontogenese, genetique et approche physiologique du caractere isomature chez le tournesol (helianthus annuus l. )." Clermont-Ferrand 2, 1986. http://www.theses.fr/1986CLF21028.

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Le nouveau genotype wjr::(1629) de tournesol (helianthus annuus l. , seconde plante oleagineuse du monde) est remarquable par son caractere isomature : il possede deux ou plusieurs capitules symetriques qui fleurissent et murissent simultanement. Son interet sur le plan agronomique est prometteur. Il est mis en evidence que la realisation du caractere isomature est sous la dependance de un a trois genes dominants et d'un effet maternel. Ce resultat impliquera necessairement, dans le futur, l'utilisation d'un parent femelle isomature pour le creation d'hybrides commerciaux
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Wong, Jhih-Ying, and 翁芷瑩. "APR gene regulates diet-induced obesity on metabolic traits in mice." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/j9cy56.

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碩士
國立中興大學
獸醫學系暨研究所
106
Insulin resistance is a common cause of many metabolic disorders, including metabolic syndrome, obesity and type 2 diabetes. All of them are increasing at epidemic rate and has become one of the most serious threats to human health. Adipose tissue has a correlation with lipid metabolism and energy balance. Adipose chronic inflammation and ectopic lipid accumulation leading to glucose intolerance and insulin resistance, which is correlated with hyperinsulinemia and pancreatic islet hypertrophy. Our aim is to study the effect of Asteraceae phytochemical receptor (APR) gene knockdown regulating development of obesity on metabolic trait in mice. Both APR knockout (APR KO, n=16) mice and wild-type (WT, n=16) male mice of C57B/L6 background were randomly divided into 4 groups and either maintained on normal diet (ND) or high-fat diet (HFD) for 12 consecutive weeks. It was interestingly noted that HFD KO mice significantly decreased body weight, which was associated with lower adipose tissue expansion, dyslipidemia, insulin resistance, and hepatic steatosis compared to HFD mice. These results suggest that targeting APR gene may be an effective strategy for combating obesity-related metabolic disease.
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Kuo, Wen-Shuo, and 郭文碩. "Gene Expression And Physiological Analysis Of Sponge Gourd APX Gene And Winter Squash SOD Gene Under Respective Flooding And Chilling Stresses." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/85478413517520782019.

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碩士
中國文化大學
生物科技研究所
100
Bitter gourd is one of the most important economical vegetables in Taiwan. However, the growth and development of the plants are strongly influenced by flooding and chilling stresses that can be initiated by oxidative stress. Bitter gourds have been grafted onto the sponge gourd and winter squash to cope with flooding and chilling stresses due to its susceptible to both conditions. These scions have developed a series of defense mechanisms and detoxification systems including antioxidants and enzymes to scavenge the reactive oxidative species (ROS). The objectives of our work were to study the changes of physiological parameters in bitter gourd, sponge gourd and winter squash, and identify any antioxidant enzyme under flooding and chilling stresses. The phenotypic traits, physiological parameters (variable fluorescence/maximum fluorescence, electrolyte leakage, malondialdehyde), and antioxidant enzymes (APX, CAT, SOD, and GR) were measured during different time periods of stress. The results of the study show that the physiological damages include chlorophyll breakdown, membrane permeability increased, and caused lipid peroxidation. The value of Fv/Fm was decreased under flooding and chilling stresses. The APX activity between sponge gourd and bitter gourd was found to be significant difference under flooding stress. APX mRNA transcripts of sponge gourd were relatively higher than bitter gourd based on real-time PCR analysis using actin as internal control.SOD activity between bitter gourd and winter squash was significantly different under chilling stress. Therefore, APX gene from the flooding-tolerant sponge gourd was identified and isolated using RACE technology. Both APX and SOD genes were cloned into E. Coli using transformation methodology. The results may be helpful to those bitter gourd farmers to reduce damages of the plants, and also be informative to screen for suitable scions and for stress tolerant breeding as well.
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Books on the topic "AprX gene"

1

International Crops Research Institute for the Semi-arid Tropics. and Wageningen Universiteit. Virology Dept., eds. Transformation and regeneration of groundnut, and utilization of viral genes to induce resistance to virus diseases: Summary and recommendations of a meeting, 24-27, Apr 1992, Virology Department, Wageningen Agricultural University, the Netherlands. Patancheru: International Crops Research Institute for the Semi-Arid Tropics, 1992.

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International Crops Research Institute for the Semi-arid Tropics., ed. Transformation and regeneration of groundnut, and utilization of viral genes to induce resistance to virus diseases: Summary and recommendations of a meeting, 24-27 Apr 1992, Virology Department, Wageningen Agricultural University, The Netherlands. Patancheru, Andhra Pradesh, India: ICRISAT, 1992.

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International Crops Research Institute for the Semi-arid Tropics. and Wageningen Universiteit. Virology Dept., eds. Transformation and regeneration of groundnut, and utilization of viral genes to induce resistance to virus diseases: Summary and recommendations of a meeting, 24-27, Apr 1992, Virology Department, Wageningen Agricultural University, the Netherlands. Patancheru: International Crops Research Institute for the Semi-Arid Tropics, 1992.

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Lowy, Israel. Isolation and characterization of the hamster aprt gene. 1991.

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CULLEN, B. Cullen: Mechanisms of Control of Gene Expression (Proc.Steamboat Springs, Colorado Apr 87. John Wiley & Sons Inc, 1988.

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Daniel, Rob. Cape Fear. Liverpool University Press, 2022. http://dx.doi.org/10.3828/liverpool/9781800857018.001.0001.

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Can a film made in one genre be better understood by viewing it as another? This book investigates this question in relation to Martin Scorsese’s 1991 remake of Cape Fear. Scorsese approached the film as a thriller, but Cape Fear is thematically and formally more coherent when viewed as a horror film. Across an introduction and five chapters, this book explores why this is the case. How Scorsese’s Catholicism and passion for horror has informed artistic decisions throughout his career, and the ways in which it reached an apex when he directed Cape Fear. The ways in which conventions of Gothic literature and fairy tales influenced this richly metatextual film, plus the impact of historical trends in horror cinema. How Robert De Niro’s research into antagonist Max Cady created a character who is closer to cinematic bogeymen rather than the more earthbound villains expected in thrillers. Film theory models around genre are utilised, along with interviews with key personnel on the film. Including a primary source interview with screenwriter Wesley Strick, who relates his experiences. Scorsese’s hyper-stylised directorial technique in Cape Fear is analysed for the ways in which it works to creates sensations typically associated with horror cinema, and the film’s legacy is also reviewed. Sexual politics and the controversy that surrounded Cape Fear’s depiction of sexual threat is also analysed, within the context of Scorsese’s depiction of women and accusations of misogyny that have been levelled against him during his career.
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Reddy, D. V. Transformation and Regeneration of Groundnut, and Utilization of Viral Genes to Induce Resistance to Virus Diseases Summary and Recommendations of a Meeting 24-27 Apr. 1992. International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), 1992.

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Transformation and regeneration of groundnut, and utilization of viral genes to induce resistance to virus diseases: Summary and recommendations of a meeting, 24-27 Apr 1992. Patancheru: International Crops Research Institute for the Semi-Arid Tropics, 1992.

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Book chapters on the topic "AprX gene"

1

Hershey, Howard V., and Milton W. Taylor. "Sequence of the E. Coli APRT Gene." In Purine and Pyrimidine Metabolism in Man V, 239–46. Boston, MA: Springer US, 1986. http://dx.doi.org/10.1007/978-1-4684-5104-7_38.

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Turker, Mitchell S., Padmaja Mummaneni, and Gregory E. Cooper. "The Mouse APRT Gene as a Model for Studying Epigenetic Gene Inactivation." In Purine and Pyrimidine Metabolism in Man VIII, 647–52. Boston, MA: Springer US, 1995. http://dx.doi.org/10.1007/978-1-4615-2584-4_134.

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Boyadjiev, Simeon A., Amrik Sahota, and Jay A. Tischfield. "Identification of Polymorphic Markers Flanking the Human APRT Gene." In Purine and Pyrimidine Metabolism in Man VIII, 657–60. Boston, MA: Springer US, 1995. http://dx.doi.org/10.1007/978-1-4615-2584-4_136.

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Crother, Timothy R., and Milton W. Taylor. "Relationship of the Two APRT Gene Products from saccharomyces Cerevisiae." In Advances in Experimental Medicine and Biology, 309–14. Boston, MA: Springer US, 1998. http://dx.doi.org/10.1007/978-1-4615-5381-6_61.

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She, Bin Ru, and Milton W. Taylor. "Analysis of the Promoter Region of the CHO APRT Gene." In Advances in Experimental Medicine and Biology, 77–81. New York, NY: Springer US, 1991. http://dx.doi.org/10.1007/978-1-4615-7703-4_17.

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Taylor, Milton W., Joo-Hung Park, and De-Chu Tang. "An Analysis of 5′ Regulatory Sequences of the Hamster APRT Gene." In Advances in Experimental Medicine and Biology, 467–73. Boston, MA: Springer US, 1989. http://dx.doi.org/10.1007/978-1-4684-5673-8_76.

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Park, Joo Hung, and Milton W. Taylor. "Analysis of the Transcriptional Regulatory Sequences in the CHO APRT Gene." In Purine and Pyrimidine Metabolism in Man V, 259–64. Boston, MA: Springer US, 1986. http://dx.doi.org/10.1007/978-1-4684-5104-7_41.

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She, Bin-Ru, and Milton W. Taylor. "The Promoter of the Cho APRT Gene Contains Three Regulatory Regions." In Purine and Pyrimidine Metabolism in Man VIII, 641–45. Boston, MA: Springer US, 1995. http://dx.doi.org/10.1007/978-1-4615-2584-4_133.

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Wang, Qing, Vincent Konan, and Milton W. Taylor. "Expression of the APRT Gene in an Adenovirus Vector System as a Model for Studying Gene Therapy." In Advances in Experimental Medicine and Biology, 61–66. New York, NY: Springer US, 1991. http://dx.doi.org/10.1007/978-1-4615-7703-4_14.

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Zaghloul, Taha I. "Cloned Bacillus subtilis Alkaline Protease (aprA) Gene Showing High Level of Keratinolytic Activity." In Biotechnology for Fuels and Chemicals, 199–205. Totowa, NJ: Humana Press, 1998. http://dx.doi.org/10.1007/978-1-4612-1814-2_19.

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Conference papers on the topic "AprX gene"

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Kim, Marianne K. H., Dong J. Min, Mike Rabin, and Jonathan D. Licht. "Abstract 1126: Gene expression profiling reveals that WT1 and WTX control cell growth through similar gene networks but different specific genes." In Proceedings: AACR 101st Annual Meeting 2010‐‐ Apr 17‐21, 2010; Washington, DC. American Association for Cancer Research, 2010. http://dx.doi.org/10.1158/1538-7445.am10-1126.

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Marino, Natascia, Joshua W. Collins, Changyu Shen, George W. Sledge, and Patricia S. Steeg. "Abstract 3871: Analysis of gene expression patterns downstream of multiple metastatic suppressor genes." In Proceedings: AACR 104th Annual Meeting 2013; Apr 6-10, 2013; Washington, DC. American Association for Cancer Research, 2013. http://dx.doi.org/10.1158/1538-7445.am2013-3871.

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Kim, Han Sang, Sang Cheol Kim, Chan Hee Park, Sang Joon Shin, Joong Bae Ahn, Hei-Cheul Jeung, Hyun Cheol Chung, Jae Kyung Roh, and Sun Young Rha. "Abstract 3907: Gene expression profile of aging-related genes in human gastric cancer development." In Proceedings: AACR 102nd Annual Meeting 2011‐‐ Apr 2‐6, 2011; Orlando, FL. American Association for Cancer Research, 2011. http://dx.doi.org/10.1158/1538-7445.am2011-3907.

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Bollig-Fischer, Aliccia B., and Stephen P. Ethier. "Abstract 114: Identification of HER2 oncogene-regulated genes and pathways from dynamic gene expression data." In Proceedings: AACR 101st Annual Meeting 2010‐‐ Apr 17‐21, 2010; Washington, DC. American Association for Cancer Research, 2010. http://dx.doi.org/10.1158/1538-7445.am10-114.

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Thomas, Geethu Elizabath, R. Aswati Nair, M. Sabu, and George Thomas. "Molecular evolution of APR-5protein gene inZingiberspecies with contrasting breeding systems." In the International Symposium. New York, New York, USA: ACM Press, 2010. http://dx.doi.org/10.1145/1722024.1722027.

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Perez-Mayoral, Julyann, Jaime L. Matta, and Julie Dutil. "Abstract 4204: Gene expression changes of DNA repair genes in lymphocytes of breast cancer patients." In Proceedings: AACR 103rd Annual Meeting 2012‐‐ Mar 31‐Apr 4, 2012; Chicago, IL. American Association for Cancer Research, 2012. http://dx.doi.org/10.1158/1538-7445.am2012-4204.

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Mendonca, Maria Cecilia F., Thomas C. Newton, Giselle Sholler, and Stephen S. Roberts. "Abstract 1442: Side population analysis and gene expression profiling identify Notch pathway genes in neuroblastoma." In Proceedings: AACR 103rd Annual Meeting 2012‐‐ Mar 31‐Apr 4, 2012; Chicago, IL. American Association for Cancer Research, 2012. http://dx.doi.org/10.1158/1538-7445.am2012-1442.

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Dunn, Andrew R., Shuqiang Li, Cecilia A. Fernandez, and Anthony P. Shuber. "Abstract 43: Detection of bladder cancer-associated gene methylation using next-gen bisulfite sequencing." In Proceedings: AACR 104th Annual Meeting 2013; Apr 6-10, 2013; Washington, DC. American Association for Cancer Research, 2013. http://dx.doi.org/10.1158/1538-7445.am2013-43.

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Agnihotri, Sameer, Christian A. Smith, Cynthia Hawkins, William L. Stanford, and Abhijit Guha. "Abstract 4126: Identifying novel tumor modifier genes involved in gliomagenesis using retroviral gene-trapping mutagenesis screens." In Proceedings: AACR 101st Annual Meeting 2010‐‐ Apr 17‐21, 2010; Washington, DC. American Association for Cancer Research, 2010. http://dx.doi.org/10.1158/1538-7445.am10-4126.

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Kuijjer, Marieke L., Halfdan Rydbeck, Stine H. Kresse, Emilie P. Buddingh, Helene Roelofs, Horst Bürger, Ola Myklebost, Pancras CW Hogendoorn, Leonardo A. Meza-Zepeda, and Anne-Marie Cleton-Jansen. "Abstract 5128: Identification of osteosarcoma driver genes by integrative analysis of copy number and gene expression data." In Proceedings: AACR 103rd Annual Meeting 2012‐‐ Mar 31‐Apr 4, 2012; Chicago, IL. American Association for Cancer Research, 2012. http://dx.doi.org/10.1158/1538-7445.am2012-5128.

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Reports on the topic "AprX gene"

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MacInnes, M., M. R. Altherr, D. Ludwig, R. Pedersen, and C. Mold. The biology of novel animal genes: Mouse APEX gene knockout. Office of Scientific and Technical Information (OSTI), July 1997. http://dx.doi.org/10.2172/505320.

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Dubcovsky, Jorge, Tzion Fahima, and Ann Blechl. Molecular characterization and deployment of the high-temperature adult plant stripe rust resistance gene Yr36 from wheat. United States Department of Agriculture, November 2013. http://dx.doi.org/10.32747/2013.7699860.bard.

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Stripe rust, caused by Puccinia striiformis f. sp. tritici is one of the most destructive fungal diseases of wheat. Virulent races that appeared within the last decade caused drastic cuts in yields. The incorporation of genetic resistance against this pathogen is the most cost-effective and environmentally friendly solution to this problem. However, race specific seedling resistance genes provide only a temporary solution because fungal populations rapidly evolve to overcome this type of resistance. In contrast, high temperature adult plant (HTAP) resistance genes provide a broad spectrum resistance that is partial and more durable. The cloning of the first wheat HTAP stripe rust resistance gene Yr36 (Science 2009, 323:1357), funded by our previous (2007-2010) BARD grant, provided us for the first time with an entry point for understanding the mechanism of broad spectrum resistance. Two paralogous copies of this gene are tightly linked at the Yr36 locus (WKS1 and WKS2). The main objectives of the current study were to characterize the Yr36 (WKS) resistance mechanism and to identify and characterize alternative WKSgenes in wheat and wild relatives. We report here that the protein coded by Yr36, designated WKS1, that has a novel architecture with a functional kinase and a lipid binding START domain, is localized to chloroplast. Our results suggest that the presence of the START domain may affect the kinase activity. We have found that the WKS1 was over-expressed on leaf necrosis in wheat transgenic plants. When the isolated WKS1.1 splice variant transcript was transformed into susceptible wheat it conferred resistance to stripe rust, but the truncated variant WKS1.2 did not confer resistance. WKS1.1 and WKS1.2 showed different lipid binding profiling. WKS1.1 enters the chloroplast membrane, while WKS1.2 is only attached outside of the chloroplast membrane. The ascorbate peroxidase (APX) activity of the recombinant protein of TmtAPXwas found to be reduced by WKS1.1 protein in vitro. The WKS1.1 mature protein in the chloroplast is able to phosphorylate TmtAPXprotein in vivo. WKS1.1 induced cell death by suppressing APX activity and reducing the ability of the cell to detoxify reactive oxygen. The decrease of APX activity reduces the ability of the plant to detoxify the reactive H2O2 and is the possible mechanism underlying the accelerated cell death observed in the transgenic plants overexpressing WKS1.1 and in the regions surrounding a stripe rust infection in the wheat plants carrying the natural WKS1.1 gene. WKS2 is a nonfunctional paralog of WKS1 in wild emmer wheat, probably due to a retrotransposon insertion close to the alternative splicing site. In some other wild relatives of wheat, such as Aegilops comosa, there is only one copy of this gene, highly similar to WKS2, which is lucking the retrotransposon insertion. WKS2 gene present in wheat and WKS2-Ae from A. showed a different pattern of alternative splice variants, regardless of the presence of the retrotransposon insertion. Susceptible Bobwhite transformed with WKS2-Ae (without retrotansposon insertion in intron10), which derived from Aegilops comosaconferred resistance to stripe rust in wheat. The expression of WKS2-Ae in transgenic plants is up-regulated by temperature and pathogen infection. Combination of WKS1 and WKS2-Ae shows improved stripe rust resistance in WKS1×WKS2-Ae F1 hybrid plants. The obtained results show that WKS1 protein is accelerating programmed cell death observed in the regions surrounding a stripe rust infection in the wheat plants carrying the natural or transgenic WKS1 gene. Furthermore, characterization of the epistatic interactions of Yr36 and Yr18 demonstrated that these two genes have additive effects and can therefore be combined to increase partial resistance to this devastating pathogen of wheat. These achievements may have a broad impact on wheat breeding efforts attempting to protect wheat yields against one of the most devastating wheat pathogen.
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Sela, Hanan, Eduard Akhunov, and Brian J. Steffenson. Population genomics, linkage disequilibrium and association mapping of stripe rust resistance genes in wild emmer wheat, Triticum turgidum ssp. dicoccoides. United States Department of Agriculture, January 2014. http://dx.doi.org/10.32747/2014.7598170.bard.

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The primary goals of this project were: (1) development of a genetically characterized association panel of wild emmer for high resolution analysis of the genetic basis of complex traits; (2) characterization and mapping of genes and QTL for seedling and adult plant resistance to stripe rust in wild emmer populations; (3) characterization of LD patterns along wild emmer chromosomes; (4) elucidation of the multi-locus genetic structure of wild emmer populations and its correlation with geo-climatic variables at the collection sites. Introduction In recent years, Stripe (yellow) rust (Yr) caused by Pucciniastriiformis f. sp. tritici(PST) has become a major threat to wheat crops in many parts of the world. New races have overcome most of the known resistances. It is essential, therefore, that the search for new genes will continue, followed by their mapping by molecular markers and introgression into the elite varieties by marker-assisted selection (MAS). The reservoir of genes for disease and pest resistance in wild emmer wheat (Triticumdicoccoides) is an important resource that must be made available to wheat breeders. The majority of resistance genes that were introgressed so far in cultivated wheat are resistance (R) genes. These genes, though confering near-immunity from the seedling stage, are often overcome by the pathogen in a short period after being deployed over vast production areas. On the other hand, adult-plant resistance (APR) is usually more durable since it is, in many cases, polygenic and confers partial resistance that may put less selective pressure on the pathogen. In this project, we have screened a collection of 480 wild emmer accessions originating from Israel for APR and seedling resistance to PST. Seedling resistance was tested against one Israeli and 3 North American PST isolates. APR was tested on accessions that did not have seedling resistance. The APR screen was conducted in two fields in Israel and in one field in the USA over 3 years for a total of 11 replicates. We have found about 20 accessions that have moderate stripe rust APR with infection type (IT<5), and about 20 additional accessions that have novel seedling resistance (IT<3). We have genotyped the collection using genotyping by sequencing (GBS) and the 90K SNP chip array. GBS yielded a total 341K SNP that were filtered to 150K informative SNP. The 90K assay resulted in 11K informative SNP. We have conducted a genome-wide association scan (GWAS) and found one significant locus on 6BL ( -log p >5). Two novel loci were found for seedling resistance. Further investigation of the 6BL locus and the effect of Yr36 showed that the 6BL locus and the Yr36 have additive effect and that the presence of favorable alleles of both loci results in reduction of 2 grades in the IT score. To identify alleles conferring adaption to extreme climatic conditions, we have associated the patterns of genomic variation in wild emmer with historic climate data from the accessions’ collection sites. The analysis of population stratification revealed four genetically distinct groups of wild emmer accessions coinciding with their geographic distribution. Partitioning of genomic variance showed that geographic location and climate together explain 43% of SNPs among emmer accessions with 19% of SNPs affected by climatic factors. The top three bioclimatic factors driving SNP distribution were temperature seasonality, precipitation seasonality, and isothermality. Association mapping approaches revealed 57 SNPs associated with these bio-climatic variables. Out of 21 unique genomic regions controlling heading date variation, 10 (~50%) overlapped with SNPs showing significant association with at least one of the three bioclimatic variables. This result suggests that a substantial part of the genomic variation associated with local adaptation in wild emmer is driven by selection acting on loci regulating flowering. Conclusions: Wild emmer can serve as a good source for novel APR and seedling R genes for stripe rust resistance. APR for stripe rust is a complex trait conferred by several loci that may have an additive effect. GWAS is feasible in the wild emmer population, however, its detection power is limited. A panel of wild emmer tagged with more than 150K SNP is available for further GWAS of important traits. The insights gained by the bioclimatic-gentic associations should be taken into consideration when planning conservation strategies.
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