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Auswahl der wissenschaftlichen Literatur zum Thema „Pioneer bacteria“
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Zeitschriftenartikel zum Thema "Pioneer bacteria"
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Ayyappadasan, G., S. Rubavathi und V. Venkatraman. „Lichenized Bacteria: A Pioneer Source of Biomedical and Environmental Protection“. International Journal of Research and Review 11, Nr. 1 (29.01.2024): 494–500. http://dx.doi.org/10.52403/ijrr.20240155.
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The review highlights the synthesis of secondary metabolites by symbiotic bacteria, emphasizing the importance of these compounds in various stages of symbiotic interactions. Recognizing the roles of natural products, such as complex polyketides and nonribosomal peptides, extends from partner recognition and invasion to establishing bacterial populations, providing nutrition, and contributing to chemical defense. Notably, the study focuses on unculturable symbionts, with cultivation-independent techniques playing a significant role in advancing research in this field. The notion is that bacterial symbionts, particularly in marine invertebrates like sponges, are likely the actual producers of numerous drug candidates found in these organisms. Sponges, recognized as a significant source of biologically active natural products, are often thought to harbor compounds originating from bacteria. Biofouling, the unwanted buildup of microorganisms on submerged structures and living marine organisms, presents economic challenges, including increased fuel consumption and metal corrosion. Diverse studies, spanning morphology, biochemistry, and molecular characteristics, highlight the complexity of biofouling. To address these issues and mitigate economic losses, there is a pressing need to identify effective natural antifouling agents capable of controlling the abundant biofouling bacteria in marine environments. Keywords: Antifouling, Symbionts, Lichen, Parmeloid
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Liang, Ting, Wenqiang Zhao, Yongping Kou, Jia Liu und Qing Liu. „Soil Microbial and Organic Carbon Legacies of Pre-Existing Plants Drive Pioneer Tree Growth during Subalpine Forest Succession“. Forests 13, Nr. 7 (15.07.2022): 1110. http://dx.doi.org/10.3390/f13071110.
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Fast-growing pioneer tree species play a crucial role in triggering late successional development in forests. Experimental evidence of the soil legacy effects of pre-existing plants on pioneer tree performance is lacking. We explored the legacy effects of soils conditioned by early successional herbs (Poa poophagorum Bor and Potentilla fragarioides L.) and mid-successional shrubs (Rhododendron fortunei Lindl. and Enkianthus quinqueflorus Lour.) on late-successional ectomycorrhizal (ECM) pioneer tree (Betula platyphylla Sukaczev) seedling growth. The soils were analyzed for soil nutrient status and fungal and bacterial compositions using ITS and 16S rRNA gene sequencing. B. platyphylla seedlings produced higher biomass in soils conditioned by shrubs. Soil organic carbon (SOC) and bacterial and fungal legacies most impacted pioneer tree seedling growth. Additionally, the partial least squares path model revealed that soil nutrients, especially SOC, indirectly affected seedling biomass by their direct effects on the bacterial and fungal communities. The changes in bacterial community composition had a stronger effect on seedling biomass than those of fungi because bacteria with shorter turnover times are generally considered to be more efficient than fungi in enhancing nutrient availability. Our study integrates soil microbial and nutrient legacies to explain the potential mechanisms of pioneer tree regeneration.
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Scortichini, M., A. Belisario und E. Motta. „Bacterial Species in Relation to Forest Tree Decline“. Arboriculture & Urban Forestry 17, Nr. 9 (01.09.1991): 246–49. http://dx.doi.org/10.48044/jauf.1991.057.
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Bacterial species colonize trees endophytically without causing apparent damage, but can act as facultative parasites by utilizing tissues altered by abioticfactors. Bacteria, especially anaerobic species, can cause wetwood perse and act as pioneer microorganisms that prepare substrates for decay fungi. Xylella fastidiosa, a xylem-limited bacterium, acts as a primary pathogen inciting leaf scorch and dieback in some trees. Bacterial penetration occurs via wounds in the aerial part of the plant or in the roots. Some bacteria can act as agents of ice formation (ice nucleation active bacteria) also promoting the entry of other organisms.
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Wächtershäuser, Günter. „From volcanic origins of chemoautotrophic life to Bacteria, Archaea and Eukarya“. Philosophical Transactions of the Royal Society B: Biological Sciences 361, Nr. 1474 (07.09.2006): 1787–808. http://dx.doi.org/10.1098/rstb.2006.1904.
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The theory of a chemoautotrophic origin of life in a volcanic iron–sulphur world postulates a pioneer organism at sites of reducing volcanic exhalations. The pioneer organism is characterized by a composite structure with an inorganic substructure and an organic superstructure. Within the surfaces of the inorganic substructure iron, cobalt, nickel and other transition metal centres with sulphido, carbonyl and other ligands were catalytically active and promoted the growth of the organic superstructure through carbon fixation, driven by the reducing potential of the volcanic exhalations. This pioneer metabolism was reproductive by an autocatalytic feedback mechanism. Some organic products served as ligands for activating catalytic metal centres whence they arose. The unitary structure–function relationship of the pioneer organism later gave rise to two major strands of evolution: cellularization and emergence of the genetic machinery. This early phase of evolution ended with segregation of the domains Bacteria, Archaea and Eukarya from a rapidly evolving population of pre-cells. Thus, life started with an initial, direct, deterministic chemical mechanism of evolution giving rise to a later, indirect, stochastic, genetic mechanism of evolution and the upward evolution of life by increase of complexity is grounded ultimately in the synthetic redox chemistry of the pioneer organism.
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Doll-Nikutta, Katharina, Andreas Winkel, Ines Yang, Anna Josefine Grote, Nils Meier, Mosaieb Habib, Henning Menzel, Peter Behrens und Meike Stiesch. „Adhesion Forces of Oral Bacteria to Titanium and the Correlation with Biophysical Cellular Characteristics“. Bioengineering 9, Nr. 10 (17.10.2022): 567. http://dx.doi.org/10.3390/bioengineering9100567.
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Bacterial adhesion to dental implants is the onset for the development of pathological biofilms. Reliable characterization of this initial process is the basis towards the development of anti-biofilm strategies. In the present study, single-cell force spectroscopy (SCFS), by means of an atomic force microscope connected to a microfluidic pressure control system (FluidFM), was used to comparably measure adhesion forces of different oral bacteria within a similar experimental setup to the common implant material titanium. The bacteria selected belong to different ecological niches in oral biofilms: the commensal pioneers Streptococcus oralis and Actinomyces naeslundii; secondary colonizer Veillonella dispar; and the late colonizing pathogens Porphyromonas gingivalis as well as fimbriated and non-fimbriated Aggregatibacter actinomycetemcomitans. The results showed highest values for early colonizing pioneer species, strengthening the link between adhesion forces and bacteria’s role in oral biofilm development. Additionally, the correlation between biophysical cellular characteristics and SCFS results across species was analyzed. Here, distinct correlations between electrostatically driven maximum adhesion force, bacterial surface elasticity and surface charge as well as single-molecule attachment points, stretching capability and metabolic activity, could be identified. Therefore, this study provides a step towards the detailed understanding of oral bacteria initial adhesion and could support the development of infection-resistant implant materials in future.
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Li, Junmin, Zexin Jin und Qiping Gu. „Effect of plant species on the function and structure of the bacterial community in the rhizosphere of lead–zinc mine tailings in Zhejiang, China“. Canadian Journal of Microbiology 57, Nr. 7 (Juli 2011): 569–77. http://dx.doi.org/10.1139/w11-054.
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To uncover the role played by pioneer plants in the natural succession of vegetation on heavy-metal mine tailings, it is important to explore the sensitive indicator of rhizosphere microbial community performance. We investigated the structure and function of rhizosphere bacterial communities of five pioneer plants growing on lead–zinc mine tailings in Zhejiang, China. Compared with the control, all five pioneer plants differentially affected the structure and function of rhizosphere bacterial communities. The number of bacteria, the activity of β-glucosidase and urease, and species richness indices were the highest in the rhizosphere of Erigeron annuus . The carbon utilization ability and the functional diversity indices were the highest in the rhizosphere of Lysimachia clethroides . There was no significant relationship between the functional or structural diversity indices and the bioavailable heavy-metal content among each species. Clustering analysis and the nonmetric dimensional scaling biplot showed that the rhizosphere bacterial communities of the five pioneer plants were different from those of control, indicating that plant species might be the main driver of microbial community composition on mine tailings. Both L. clethroides and E. annuus might be appropriate candidates for phytoremediation of mine tailings for higher soil microbial community function and species richness in rhizosphere.
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Laukens, D. „ECCO Pioneer Award Functional assessment of the microbiome in persistent IBD-related psychological symptoms“. Journal of Crohn's and Colitis 18, Supplement_1 (01.01.2024): i2258. http://dx.doi.org/10.1093/ecco-jcc/jjad212.1421.
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Abstract Background and Aims It is well established that patients with inflammatory bowel disease (IBD) experience psychological comorbidities, and that these symptoms persist upon remission of the IBD in more than 50% of patients. The mechanisms underlying this clinical association are unknown, which hampers to objectify the problem and limits the possibilities to intelligently consider targeted treatments. We recently observed behavioral anomalies and neuroinflammation in a mouse model of extinguished chronic colitis, enabling the fundamental study of psychological symptoms in IBD. Fueled by technical evolutions to characterize translationally active bacteria at the single-cell level, their importance in colitis, and a proof-of-concept stool transplantation experiment, the purpose of this project is to determine if specific bacterial functions drive persistent neuroinflammation upon IBD remission. Methods First, a state-of-the-art flow-cytometry based method will be used to temporally map translationally active bacteria during the course of extinguished chronic colitis. Second, the same functional microbial analysis will be achieved in human fecal samples of IBD patients in remission before and after treatment for fatigue, and results will be compared with persistent bacterial changes found in mouse flora. Finally, causality of associated bacteria to induce neuroinflammation will be tested by transplantation studies of bacterial communities isolated from the previous tasks. Anticipated Impact This research may impact the field in the short-term by creating solid scientific awareness that psychological comorbidities are intrinsically linked with IBD remission, and by more specifically attributing a role for specific bacterial functions in these symptoms. In addition, the technique applied may open novel insights for the IBD microbiome community. In the medium-term, this project aims to shed light on the actual bacterial mechanisms that lead to neuroinflammation and behavioral anomalies, which in the long-term could help identify biomarkers for diagnostic purposes or microbiome-related targets to design rational therapeutics for patients with IBD suffering from psychological comorbidities.
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Apoorva, SM, A. Suchetha, DB Mundinamane, DP Bhopale, A. Bharwani und R. Prasad. „An Insight into the Role of Benefical Bacteria in Periodontal Pocket Recolonization: A Literature Review“. Journal of Oral Health and Community Dentistry 8, Nr. 1 (Januar 2014): 47–50. http://dx.doi.org/10.5005/johcd-8-1-47.
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ABSTRACT Microflora can be found in both caries-free and periodontitis-free people and caries-affected and periodontitis-affected people, and many clinical studies reveal that the portion of certain bacterial species such as Streptococcus mutans or Porphyromonas gingivalis, respectively, is increased in patients with caries or periodontitis. Therefore, it seems that the competition that results between beneficial bacteria and virulent bacteria leads to either a healthy or sick status of human beings. Competition between members of the dental microflora and there role in pocket recolonization is very complex and many antagonistic characteristics can be observed from competition for initial attachment on tooth surfaces or for later attachment to pioneer bacteria, competition from bacteriocins or hydrogen peroxide secreted and from facilitating the growth of some species which inhibit other species. To date only some of the details of these mechanisms are known. The present review will provide an overview on the prevalence of beneficial bacteria and the major mechanisms of oral bacterial interactions. Due to the large number of oral bacterial species, only the best characterized species are included in this review.
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Handayani, D. P., Sulastri, I. S. Bidara, S. Himawati, N. A. Saryanah und R. Reninta. „The Application of endophytic halotolerant bacteria in modulating the development of maize seedlings under salinity“. IOP Conference Series: Earth and Environmental Science 1182, Nr. 1 (01.06.2023): 012042. http://dx.doi.org/10.1088/1755-1315/1182/1/012042.
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Abstract Salinity stress has negative effects on plants physiologically as well as lowering productivity. Application of microbial inoculant as seed treatment is one of the bio-techniques that have proved to be efficient in enhancing salinity resilience in agriculture, especially for seedling development. This study aims to determine the effect of inoculation of halotolerant bacteria consortium on the development of maize seedlings under saline stress. The experiment used four different bacterial consortia namely B5 (two species of phosphate solubilizing bacteria); B6 (phosphate solubilizing bacteria, and ACC deaminase producing bacteria); B7 (phosphate solubilizing bacteria and nitrogen-fixing bacteria) and B9 (phosphate solubilizing bacteria, ACC deaminase producing bacteria and nitrogen-fixing bacteria). The salinity stress was conducted by adding NaCl with a concentration of 0, 50, 100, and 150 mM to the Hoagland nutrient solution as a germination medium. The inoculation bacteria increased the root length, root number, shoot length, fresh weight, and chlorophyll content of Pioneer maize seedling up to 25% at salinity stress treatment 150 mM NaCl. The highest increase in seedlings growth parameters was observed on seedlings inoculated by B5, B7, and B9 under a salinity treatment of 150 mM.
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Lathifah, A. N., A. A. Asmara, F. A. N. Alfisyahr und F. B. Maziya. „Potency of Indigenous Bacteria of Mt. Merapi, Arthrobacter chlorophenolicus for Chromium (VI) Bioremediation“. IOP Conference Series: Earth and Environmental Science 933, Nr. 1 (01.11.2021): 012011. http://dx.doi.org/10.1088/1755-1315/933/1/012011.
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Abstract Chromium (VI) in the production process, such as textile, tannery, and electroplating industry, produce hazardous waste when disposed of directly into the aquatic environment. Several chromium pollutions cases, not only in water but also in the aquatic organism, occurred in some regions in Indonesia. Various methods can reduce the Chromium (VI) waste. One of them is the biological method by employing such kinds of bacteria. Arthrobacter chlorophenolicus is a pioneer bacterium of Mt. Merapi, which can survive in the minimum conditions of the bacterial primary nutrients, carbon, and nitrogen. This study aims to investigate the ability of A. chlorophenolicus to remove Cr (VI) at various concentrations. The research was carried out by growing the A. chlorophenolicus into two nutrient media conditions, minimal and rich-nutrient media containing different concentrations of Cr (VI) (5, 10, 20 ppm) for eight days. The results showed that the A. chlorophenolicus were grown on both minimal and rich-nutrient media. The A. chlorophenolicus could reduce for about 80% of 10 and 20 ppm chromium in eight days. Our results indicate that A. chlorophenolicus, the pioneer bacteria of Mt. Merapi, has a grand promise for use in Cr (VI) remediation even under minimum nutrients conditions.
Dissertationen zum Thema "Pioneer bacteria"
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Shaffer, Justin Park, und Justin Park Shaffer. „Endohyphal Bacteria of Tropical Plant-Associated Fungi: Diversity, Evolutionary Relationships, and Ecology“. Diss., The University of Arizona, 2017. http://hdl.handle.net/10150/625601.
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A growing understanding of complex biotic interactions clarified the importance of symbioses with respect to the ecology and evolution of life. In particular, knowledge of symbioses between eukaryotes and microorganisms such as bacteria and fungi has revolutionized the fields of medicine and agriculture, and made clear the roles of microbes in fostering human and environmental sustainability. For example, diverse fungi associate with the seeds of plants following dispersal. These fungi can influence seed survival and germination in a host-specific and spatially explicit manner, thus influencing plant community dynamics in agricultural and natural systems. In species-rich tropical forests, seed-fungus interactions are emerging as one of the most important aspects of plant demography and community ecology. However, even closely related fungi can have opposing effects on seeds of particular plants, such that mechanisms influencing host-specific effects require further attention. Such mechanisms can include genomic traits of fungi and hosts, and the environmental context of interactions. However, studies have shown that many fungi also harbor endosymbionts than can influence their functional traits. In particular, fungi often harbor endohyphal bacteria that influence fungal phenotypes. This suggested the potential for similar, co-occurring microbes to influence the ecology of seed-associated fungi. Here, I explore the diversity, evolutionary relationships, and influence on fungal phenotypes of endohyphal bacteria inhabiting seed- and leaf-associated fungi with a focus that begins in tropical forest ecology and expands to include gene expression in an emerging model system from the temperate zone.
To determine the occurrence, abundance, taxonomic diversity, and phylogenetic diversity of endohyphal bacteria among tropical seed-associated fungi, my coauthors and I used PCR and fluorescence microscopy to screen members of two common orders of seed-associated fungi, comparing their communities to those in closely related foliar endophytic fungi. We revealed a high frequency and diversity of endohyphal bacteria among both groups of fungi. We then used phylogenetic and community ecological analyses to show a lack of congruence between phylogenies of bacteria and fungi. Although seed-associated and foliar endophytic fungi share evolutionary histories, they harbor distinct endohyphal bacterial communities.
To explore the influence of endohyphal bacteria on fungal phenotypes important for interactions with seeds, my coauthors and I examined a single fungus-bacterium pair consisting of a member of a well-known group of pathogenic fungi found to harbor an endohyphal bacterium closely related to those with known chitinolytic activity. We created fungal clones that were free of endohyphal bacteria, and carried out a phenotypic microarray assay comparing use of 95 unique carbon sources by cured and uncured clones. Across the majority of substrates, the fungal clones harboring endohyphal bacteria grew more rapidly and to a greater extent than the cured clones. Thus the endohyphal bacterium was associated with broader substrate use and more effective use of a variety of substrates relevant to plant biology, including seed germination.
To assess the influence of endohyphal bacteria with respect to the outcomes of seed-fungus interactions, my coauthors and I examined six fungus-bacterium pairs and their interactions with the seeds of five tropical pioneer tree species. We showed that although endohyphal bacteria have little impact on colonization of seeds by fungi, they significantly altered the survival and germination of infected seeds. In most cases, endohyphal bacteria reduced the negative impacts of fungi on seeds: strains harboring them responded more similarly to uninoculated controls, whereas strains cured of them exhibited significantly reduced survival and germination. Seeds infected by fungi of the same genotype that differ with respect to the identity of their endohyphal bacteria exhibited differences, but so did seeds infected by strains of those isolates not harboring bacteria, suggesting that factors in addition to the presence of endohyphal bacteria can drive variation in the outcomes of seed-fungus interactions. Together these analyses suggest intricate interactions between fungi and bacteria that result in context-dependent outcomes. This turned our focus to gene expression as a means to understand mechanisms of interactions between endohyphal bacteria and their fungal hosts.
Last, my coauthors and I describe methods we developed to co-culture fungi and their endohyphal bacteria for downstream analysis of differences in gene expression among a fungus-bacterium pair and axenic cultures of each symbiont. We focused on an emerging model system: a foliar endophytic strain of Pestalotiopsis aff. neglecta (Ascomycota) known to harbor an endohyphal bacterium in the genus Luteibacter (Xanthomonadaceae). The focal bacterium is in part reliant on its host fungus for acquisition of certain sulfur-containing compounds such as sulfate. We showed that inoculating a low-methionine growth medium with bacteria recovered in exponential phase from a high-methionine medium supports growth suitable for comparing axenic growth with that in co-culture with its host fungus. Although bacterial cell density in co-cultures was significantly greater than that in axenic cultures, the opposite was true for the host fungus. We expect results from transcriptomics analyses to reflect partial reliance on– and antagonism of Pestalotiopsis by Luteibacter, and here present the first pipeline of methods for examining gene expression for a facultatively symbiotic endohyphal bacterium and its host, a member of the most species-rich and economically important fungal phylum.
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Brunet, Maéva. „Metabolic and ecological strategies of specialist bacteria mediating macroalgae breakdown“. Electronic Thesis or Diss., Sorbonne université, 2021. http://www.theses.fr/2021SORUS316.
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Les bactéries hétérotrophes sont des acteurs clés du recyclage de la biomasse algale. De nombreuses enzymes et voies cataboliques pour la dégradation de polysaccharides algaux purifiés ont été caractérisées. Cependant, ces mécanismes ne reflètent pas la complexité des réponses mises en œuvre pour dégrader des algues entières. J'ai donc étudié les stratégies écologiques et métaboliques de bactéries spécialistes de l'utilisation des macroalgues fraîches. La succession du microbiote épiphyte au cours de la décomposition de macroalgues a d’abord été étudiée. La présence du genre Zobellia, acteur clé de la dégradation, à la surface de diverses macroalgues a été montré. Son abondance varie selon les saisons et est particulièrement élevée dans le microbiote d’algues en décomposition. J'ai démontré que Zobellia galactanivorans DsijT utilise les algues brunes comme seule source de carbone, soulignant son rôle pionnier dans l’attaque de tissus algaux. Un ensemble de gènes, dont certains au sein de nouveaux loci dédiés à l’utilisation de polysaccharide (PUL) non caractérisés, étaient spécifiquement induits en présence d’algues. La caractérisation préliminaire de l’un de ces PUL a établi son rôle dans la dégradation de polysaccharides sulfatés contenant du fucose et conduit à la découverte de nouvelles activités enzymatiques chez Z. galactanivorans. Des interactions coopératives entre Z. galactanivorans et des Tenacibaculum spp. lors de l’utilisation de macroalgues ont été montrées. Par l’étude des mécanismes de dégradation de macroalgues à différentes échelles, cette thèse contribue à dévoiler les stratégies des bactéries marines hétérotrophes dans le devenir de la biomasse algaleHeterotrophic bacteria are key players in algal biomass recycling. Numerous works focused on the degradation of purified algal polysaccharides and discovered new enzymes and catabolic pathways. However, this strategy does not reflect the structural complexity of the algal extracellular matrix. In this thesis I implemented diverse approaches to decipher the ecological and metabolic strategies of bacteria specialized in the utilization of fresh macroalgae. I evidenced a succession of the epiphytic microbiota during in situ macroalgae decomposition. The presence of the known algal-polysaccharides degrader genus Zobellia was assessed on diverse macroalgae. Its abundance was season-dependent and particularly high on decaying algae. I demonstrated that Zobellia galactanivorans DsijT has the capacity to use fresh brown algae as a sole carbon source, highlighting a specific pioneer degrader behaviour. The analysis of its transcriptome revealed the induction of a subset of genes, including novel uncharacterized polysaccharide utilization loci (PULs), specifically induced with intact algae. The preliminary characterization of one of these PULs demonstrated its role in the degradation of fucose-containing sulfated polysaccharides and led to the discovery of novel enzymatic activities in Z. galactanivorans. Co-culture experiments showed that Z. galactanivorans supported the growth of Tenacibaculum spp. with macroalgae, bringing out cooperative interactions between pioneer and opportunist bacteria. By studying macroalgae degradation mechanisms at different scales, this thesis contributes to unveil the strategies of heterotrophic marine bacteria in the fate of macroalgal biomass
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Wilson, Kimberly M. Wilson. „Characterizing the Impact of Select Bacterial Isolates on Perinatal Pioneer Microbial Colonization and GIT Development“. The Ohio State University, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=osu1531832465230743.
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Eida, Abdul Aziz. „Bacterial Endophytes from Pioneer Desert Plants for Sustainable Agriculture“. Diss., 2020. http://hdl.handle.net/10754/663000.
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One of the major challenges for agricultural research in the 21st century is to increase crop productivity to meet the growing demand for food and feed. Biotic (e.g. plant pathogens) and abiotic stresses (e.g. soil salinity) have detrimental effects on agricultural productivity, with yield losses being as high as 60% for major crops such as barley, corn, potatoes, sorghum, soybean and wheat, especially in semi-arid regions such as Saudi Arabia. Plant growth promoting bacteria isolated from pioneer desert plants could serve as an eco-friendly, sustainable solution for improving plant growth, stress tolerance and health. In this dissertation, culture-independent amplicon sequencing of bacterial communities revealed how native desert plants influence their surrounding bacterial communities in a phylogeny-dependent manner. By culture-dependent isolation of the plant endosphere compartments and a number of bioassays, more than a hundred bacterial isolates with various biochemical properties, such as nutrient acquisition, hormone production and growth under stress conditions were obtained. From this collection, five phylogenetically diverse bacterial strains were able to promote the growth of the model plant Arabidopsis thaliana under salinity stress conditions in a common mechanism of inducing transcriptional changes of tissue-specific ion transporters and lowering Na+/K+ ratios in the shoots. By combining a number of in vitro bioassays, plant phenotyping and volatile-mediated inhibition assays with next-generation sequencing technology, gas chromatography–mass spectrometry and bioinformatics tools, a candidate strain was presented as a multi-stress tolerance promoting bacterium with potential use in agriculture. Since recent research showed the importance of microbial partners for enhancing the growth and health of plants, a review of the different factors influencing plant-associated microbial communities is presented and a framework for the successful application of microbial inoculants in agriculture is proposed. The presented work demonstrates a holistic approach for tackling agricultural challenges using microbial inoculants from desert plants by combining culturomics, phenomics, genomics and transcriptomics. Microbial inoculants are promising tools for studying abiotic stress tolerance mechanisms in plants, and they provide an eco-friendly solution for increasing crop yield in arid and semi-arid regions, especially in light of a dramatically growing human population and detrimental effects of global warming and climate change.
Buchteile zum Thema "Pioneer bacteria"
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Navarro-Noya, Yendi E., Esperanza Martínez-Romero und César Hernández-Rodríguez. „Potential Plant-Growth-Promoting and Nitrogen-Fixing Bacteria Associated with Pioneer Plants Growing on Mine Tailings“. In Molecular Microbial Ecology of the Rhizosphere, 1003–11. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2013. http://dx.doi.org/10.1002/9781118297674.ch94.
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Piqueras, Mercé. „Esther Lederberg: Pioneer of Bacterial Genetics“. In In the Company of Microbes, 59–65. Washington, DC, USA: ASM Press, 2016. http://dx.doi.org/10.1128/9781555819606.ch15.
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Elphinstone, John. „Plant Pathogens: Bacteria“. In Plant Diseases and Biosecurity. Oxford University Press, 2019. http://dx.doi.org/10.1093/hesc/9780198827726.003.0003.
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This chapter examines bacterial plant diseases which affect a wide range of crops, ornamentals, and environmentally important plants and trees. It first reviews descriptions of bacterial plant diseases by the early pioneers in plant bacteriology, wherein many different genera of bacteria which damage plants were reported. It also highlights the enormous global impact of bacterial plant diseases in both social and financial terms. The chapter outlines types of economic losses that range from minor blemishes, such as spots, areas of dead tissue, or yellowing on leaves or fruit, to more serious rots, wilts, blights, and diebacks, which can spread through and devastate entire crops or areas of natural vegetation. It elaborates on how minor symptoms of bacterial plant diseases can still be economically significant if the loss in quality affects marketability, such as in the cases of high-value ornamental plants or food crops.
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Gratzer, Walter. „Slot machine yields jackpot“. In Eurekas and euphorias, 90–92. Oxford University PressNew York, NY, 2002. http://dx.doi.org/10.1093/oso/9780192804037.003.0056.
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Abstract A remarkable example of how inspiration can come unbidden from an extraneous source is related by the geneticist Salvador Luria (1912-91). An Italian, driven out of his country by Mussolini’s antisemitic laws, he found refuge at the University of Indiana, where he launched himself into the study of bacteriophage genetics. This proved an immensely fruitful move and Luria, together with a small group of other pioneers, including Jim Watson [88], his student, and the spiritual leader of the movement, Max Delbriick in California, laid the foundations of molecular genetics, as it has evolved today. Luria had been studying the fate of bacteria infected by a bacteriophage (a virus that attacks a bacterium and multiplies within, until its numerous progeny burst open the cell and spill out, ready to attack more bacteria); he had noticed that a few colonies of bacteria in his dishes of nutrient agar gel survived the onslaught. They were clearly mutants and the question now was whether these bacteria had been transformed by the action of the bacteriophage or whether they arose by occasional spontaneous mutations that rendered them resistant to attack.
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Gilsdorf, Janet R. „The Flu and Richard Pfeiffer“. In Continual Raving, 23–56. Oxford University Press, 2019. http://dx.doi.org/10.1093/oso/9780190677312.003.0002.
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For decades, scientists puzzled over which influenza virus was actually responsible for the Russian pandemic. Finally, in 2014, phylogenetic techniques (examining evolutionary patterns of the virus genes) and seroarcheologic techniques (measuring antibodies likely present in people at various points in time) were applied to the question of which virus caused the Russian flu of 1889–1892. Thus, Pfeiffer’s proclamation that his bacillus caused influenza was finally proven wrong. His identification of Bacillus influenzae in the respiratory tract, however, was a major contribution to the scientific understanding of bacterial infections and moved the field of bacteriology forward in allowing other investigators to unearth its full potential as an important human pathogen. Further, in the course of his studies of B. influenzae, Pfeiffer pioneered the field of nutritional requirements of bacteria. Finally, Pfeiffer’s identification of Haemophilus influenzae launched subsequent studies of the causes of bacterial meningitis and initiated in-depth explorations of bacterial meningitis-causing pathogens that ground our concepts of pathogenesis, and guide our management, of the infection.
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„Marvin P. Bryant (1925–2000): Bacteria in Methanogenic Ecosystems“. In Pioneers in Microbiology, 477–84. WORLD SCIENTIFIC, 2017. http://dx.doi.org/10.1142/9789813200371_0050.
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Lee, Jeong K., und samuel Kaplan. „Molecular genetics of purple bacteria“. In Molecular Genetics of Photosynthesis, 225–46. Oxford University PressOxford, 1996. http://dx.doi.org/10.1093/oso/9780199634484.003.0011.
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Abstract In 1957 Cohen-Bazire et al. (1), noted that light intensity, as well as O2 tension could dramatically and immediately alter the cellular bacteriochlorophyll (Bchl) content of photosynthetically growing cultures of Rhodobacter sphaeroides. It became clear that the cellular levels of Bchl reflect the presence of three Bchl-carotenoid (Crt)-protein complexes (2-4) which in turn are part of the inducible photosynthetic membrane structure, referred to as the intracytoplasmic membrane (ICM) (5). Subsequent studies detailed the earliest events in light entrapment and were pioneered by many investigators, one of the earliest being Rod Clayton (3). Biochemical studies of the pathways involved in Bchl and haem were pioneered by June Lascelles and her many colleagues (6).
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„René Jules Dubos (1901–1982): Pioneer of Bacterial Antibiotics and Environmental Microbiology“. In Pioneers in Microbiology, 369–72. WORLD SCIENTIFIC, 2017. http://dx.doi.org/10.1142/9789813200371_0040.
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A, Sachith, Vandana S, Preetham R, Prof Praveen T, Ms Kavyasree D S und Dr Keshavamurthy M. „BACTERIA AS THE PIONEERS IN BIOREMEDIATION OF HAZARDOUS ENVIRONMENTAL POLLUTANTS“. In Futuristic Trends in Biotechnology Volume 2 Book 26, 218–31. Iterative International Publishers, Selfypage Developers Pvt Ltd, 2023. http://dx.doi.org/10.58532/v2bs26ch13.
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Bioremediation is the biological process by which microorganisms degrade hydrocarbons as a source of carbon. Environmental pollution has skyrocketed over the past few years due to harmful human activities. Chemical treatment on pollutants has only a limited effect, and hence bacteria and fungi are employed to efficiently degrade substrates like heavy metals, petroleum hydrocarbons and plastics. There are various factors such as temperature and pH of the environment, availability of nutrients, water and oxygen. Bioremediation of pollutants can be carried out either at the site of pollution (in-situ) or by transporting them to treatment plants (exsitu). Bacteria possess a number of biological pathways and enzymes which are specific to persistent pollutants. Advanced studies in biotechnology have helped in enhancing these processes. However, every scientific technique has its own pros and cons, and so does the process of bioremediation
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„Cornelis B. van Niel (1897–1985): Educator and Pioneer of Bacterial Photosynthesis and General Microbiology“. In Pioneers in Microbiology, 349–57. WORLD SCIENTIFIC, 2017. http://dx.doi.org/10.1142/9789813200371_0038.
Der volle Inhalt der QuelleKonferenzberichte zum Thema "Pioneer bacteria"
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Liu, Songyuan, Bo Lu, Chao-yu Sie und Yifan Li. „Bioremediation by Indigenous Microbes: A Green Approach to Degrade Polymer Residue“. In SPE Improved Oil Recovery Conference. SPE, 2022. http://dx.doi.org/10.2118/209422-ms.
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Abstract Polyacrylamide-based friction reducer is commonly used in well completion for unconventional reservoirs. However, residual polymer trapped in the near well-bore region could create unintended flow restrictions and could negatively impact oil production. An eco-friendly approach to regain conductivity was developed by stimulating indigenous bacteria for residual polymer biodegradation. In this work, a series of laboratory experiments were conducted using produced water and oil from Permian Basin, polyacrylamide-based polymer, and a modified nutrient recipe that contained 100 to 300 ppm of inorganic salts. The sealed sample vials containing water, oil, and polymer were prepared in a sterilized anaerobic chamber and then kept in a 160° F incubator to simulate the reservoir condition. Feasibility tests of bacteria growth and biodegradation evaluation of polymer were conducted using an optical laser microscopic system with bacteria tagged with fluorescent dye. Size regression was calculated and applied to a mathematical model based on actual fracture aperture distribution data from shale formation. The indigenous bacteria were successfully stimulated with and without the existence of the friction reducer. It was observed that the size of polymer particles decreased from over 300 µm to less than 20 µm after 15 days. Under the condition of produced water injection, 140° F reservoir temperature, and anaerobic environment, about 30% of the natural fractures in shale were calculated to be damaged and remediated within 15 days. This work is a pioneer research on microbial EOR application in unconventional reservoirs with only indigenous bacteria involved. In field applications, only an extremely low amount of nutrient is required in this process which provides great economic potential. Additionally, the nutrients introduced into the reservoirs will be fully consumed by bacteria during treatment, and the bacteria will be decomposed into organic molecules soon after the treatment. Thus, this technique is environmental- and economical- friendly for the purpose of polymer damage remediation to maximize the recoverable.
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„Effect of Storage Temperature, Duration and Types of Biofertilizer Carriers on Survival and Numbers of Bacterial Strains Bacillus megaterium var. phosphaticum , Azotobacter chroococcum, Rhizobium leguminosarum and Transformant, Transconjugant B. megaterium var. phosphaticum“. In Eminent Association of Pioneers. Eminent Association of Pioneers (EAP), 2016. http://dx.doi.org/10.17758/eap.eap816211.
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Dias, Grazielle Suhett, Aline Sereia, Lais Yamanaka, Paloma Rubin, Ana Christof und Luiz Felipe Valter de Oliveira. „Probiome: knowing our second genome, the gut microbiota“. In XIII Congresso Paulista de Neurologia. Zeppelini Editorial e Comunicação, 2021. http://dx.doi.org/10.5327/1516-3180.638.
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The gut microbiota a plays an important role in the physiology and pathology of the human body. In recent years, studies are unraveling how the gut microbiota influences not only health and gastrointesPnal disorders, but also other distal organs and systems. Recently, studies are been showing that gut’s bacteria can affect central nervous system physiology and inflammaPon. The gastrointesPnal tract and the nervous system communicate each other through a bidirecPonal signaling network known as brain-intesPne axis. This network is made up of mulPple connecPons that include vagus nerve, immune system and metabolisms, such as metabolites and products derived from intesPnal bacteria. Depression, MulPple Sclerosis, Alzheimer’s, Parkinson’s Disease and AuPsPc Spectrum Disorders are among the most studied neurological condiPons in the gut microbiota field. BiomeHub is a biotechnology StartUP that pioneered the development and performance of analyzes based on cuXngedge genomics and bioinformaPcs technologies applied to microbiology. The company developed the first validated Brazilian intesPnal microbiome test, which all steps are performed in Brazil, in its own infrastructure, using the state of the art in DNA sequencing technologies and analysis of biological data. Probiome is a molecular test capable of detecPng the complex bacteria community that make up the IntesPnal Microbiota, by sequencing the DNA of these bacteria. The growing knowledge accumulaPon about human microbiome allowed rapid advances and it has been building a solid foundaPon for the development of prognoses, diagnoses and clinical intervenPons, while it creates a new paradigm in personalized medicine. Probiome enables a targeted medical and nutriPonal approach through cross-checking between the profile data of the gut microbiota and the paPent clinical condiPons, assisPng in the elaboraPon of more accurate diets and therapies, selecPon of probioPcs and prebioPcs, among other approaches to gut microbiota intervenPons.
Berichte der Organisationen zum Thema "Pioneer bacteria"
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Crowley, David E., Dror Minz und Yitzhak Hadar. Shaping Plant Beneficial Rhizosphere Communities. United States Department of Agriculture, Juli 2013. http://dx.doi.org/10.32747/2013.7594387.bard.
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PGPR bacteria include taxonomically diverse bacterial species that function for improving plant mineral nutrition, stress tolerance, and disease suppression. A number of PGPR are being developed and commercialized as soil and seed inoculants, but to date, their interactions with resident bacterial populations are still poorly understood, and-almost nothing is known about the effects of soil management practices on their population size and activities. To this end, the original objectives of this research project were: 1) To examine microbial community interactions with plant-growth-promoting rhizobacteria (PGPR) and their plant hosts. 2) To explore the factors that affect PGPR population size and activity on plant root surfaces. In our original proposal, we initially prqposed the use oflow-resolution methods mainly involving the use of PCR-DGGE and PLFA profiles of community structure. However, early in the project we recognized that the methods for studying soil microbial communities were undergoing an exponential leap forward to much more high resolution methods using high-throughput sequencing. The application of these methods for studies on rhizosphere ecology thus became a central theme in these research project. Other related research by the US team focused on identifying PGPR bacterial strains and examining their effective population si~es that are required to enhance plant growth and on developing a simulation model that examines the process of root colonization. As summarized in the following report, we characterized the rhizosphere microbiome of four host plant species to determine the impact of the host (host signature effect) on resident versus active communities. Results of our studies showed a distinct plant host specific signature among wheat, maize, tomato and cucumber, based on the following three parameters: (I) each plant promoted the activity of a unique suite of soil bacterial populations; (2) significant variations were observed in the number and the degree of dominance of active populations; and (3)the level of contribution of active (rRNA-based) populations to the resident (DNA-based) community profiles. In the rhizoplane of all four plants a significant reduction of diversity was observed, relative to the bulk soil. Moreover, an increase in DNA-RNA correspondence indicated higher representation of active bacterial populations in the residing rhizoplane community. This research demonstrates that the host plant determines the bacterial community composition in its immediate vicinity, especially with respect to the active populations. Based on the studies from the US team, we suggest that the effective population size PGPR should be maintained at approximately 105 cells per gram of rhizosphere soil in the zone of elongation to obtain plant growth promotion effects, but emphasize that it is critical to also consider differences in the activity based on DNA-RNA correspondence. The results ofthis research provide fundamental new insight into the composition ofthe bacterial communities associated with plant roots, and the factors that affect their abundance and activity on root surfaces. Virtually all PGPR are multifunctional and may be expected to have diverse levels of activity with respect to production of plant growth hormones (regulation of root growth and architecture), suppression of stress ethylene (increased tolerance to drought and salinity), production of siderophores and antibiotics (disease suppression), and solubilization of phosphorus. The application of transcriptome methods pioneered in our research will ultimately lead to better understanding of how management practices such as use of compost and soil inoculants can be used to improve plant yields, stress tolerance, and disease resistance. As we look to the future, the use of metagenomic techniques combined with quantitative methods including microarrays, and quantitative peR methods that target specific genes should allow us to better classify, monitor, and manage the plant rhizosphere to improve crop yields in agricultural ecosystems. In addition, expression of several genes in rhizospheres of both cucumber and whet roots were identified, including mostly housekeeping genes. Denitrification, chemotaxis and motility genes were preferentially expressed in wheat while in cucumber roots bacterial genes involved in catalase, a large set of polysaccharide degradation and assimilatory sulfate reduction genes were preferentially expressed.