Academic literature on the topic 'Wzb phosphatase'
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Journal articles on the topic "Wzb phosphatase"
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Reid, Anne N., and Chris Whitfield. "Functional Analysis of Conserved Gene Products Involved in Assembly of Escherichia coli Capsules and Exopolysaccharides: Evidence for Molecular Recognition between Wza and Wzc for Colanic Acid Biosynthesis." Journal of Bacteriology 187, no. 15 (August 1, 2005): 5470–81. http://dx.doi.org/10.1128/jb.187.15.5470-5481.2005.
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ABSTRACT Group 1 capsular polysaccharides (CPSs) of Escherichia coli and some loosely cell-associated exopolysaccharides (EPSs), such as colanic acid, are assembled by a Wzy-dependent polymerization system. In this biosynthesis pathway, Wza, Wzb, and Wzc homologues are required for surface expression of wild-type CPS or EPS. Multimeric complexes of Wza in the outer membrane are believed to provide a channel for polymer export; Wzc is an inner membrane tyrosine autokinase and Wzb is its cognate phosphatase. This study was performed to determine whether the Wza, Wzb, and Wzc proteins for colanic acid expression in E. coli K-12 could function in the E. coli K30 prototype group 1 capsule system. When expressed together, colanic acid Wza, Wzb, and Wzc could complement a wza-wzb-wzc defect in E. coli K30, suggesting conservation in their collective function in Wzy-dependent CPS and EPS systems. Expressed individually, colanic acid Wza and Wzb could also function in K30 CPS expression. In contrast, the structural requirements for Wzc function were more stringent because colanic acid Wzc could restore translocation of K30 CPS to the cell surface only when expressed with its cognate Wza protein. Chimeric colanic acid-K30 Wzc proteins were constructed to further study this interaction. These proteins could restore K30 biosynthesis but were unable to couple synthesis to export. The chimeric protein comprising the periplasmic domain of colanic acid Wzc was functional for effective K30 CPS surface expression only when coexpressed with colanic acid Wza. These data highlight the importance of Wza-Wzc interactions in group 1 CPS assembly.
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Vincent, Carole, Patricia Doublet, Christophe Grangeasse, Elisabeth Vaganay, Alain J. Cozzone, and Bertrand Duclos. "Cells of Escherichia coli Contain a Protein-Tyrosine Kinase, Wzc, and a Phosphotyrosine-Protein Phosphatase, Wzb." Journal of Bacteriology 181, no. 11 (June 1, 1999): 3472–77. http://dx.doi.org/10.1128/jb.181.11.3472-3477.1999.
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ABSTRACT Two proteins of Escherichia coli, termed Wzc and Wzb, were analyzed for their capacity to participate in the reversible phosphorylation of proteins on tyrosine. First, Wzc was overproduced from its specific gene and purified to homogeneity by affinity chromatography. Upon incubation in the presence of radioactive ATP, it was found to effectively autophosphorylate. Two-dimensional analysis of its phosphoamino acid content revealed that it was modified exclusively at tyrosine. Second, Wzb was also overproduced from the corresponding gene and purified to homogeneity by affinity chromatography. It was shown to contain a phosphatase activity capable of cleaving the synthetic substrate p-nitrophenyl phosphate intop-nitrophenol and free phosphate. In addition, it was assayed on individual phosphorylated amino acids and appeared to dephosphorylate specifically phosphotyrosine, with no effect on phosphoserine or phosphothreonine. Such specificity for phosphotyrosine was confirmed by the observation that Wzb was able to dephosphorylate previously autophosphorylated Wzc. Together, these data demonstrate, for the first time, that E. coli cells contain both a protein-tyrosine kinase and a phosphotyrosine-protein phosphatase. They also provide evidence that this phosphatase can utilize the kinase as an endogenous substrate, which suggests the occurrence of a regulatory mechanism connected with reversible protein phosphorylation on tyrosine. From comparative analysis of amino acid sequences, Wzc was found to be similar to a number of proteins present in other bacterial species which are all involved in the synthesis or export of exopolysaccharides. Since these polymers are considered important virulence factors, we suggest that reversible protein phosphorylation on tyrosine may be part of the cascade of reactions that determine the pathogenicity of bacteria.
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Nakar, David, and David L. Gutnick. "Involvement of a Protein Tyrosine Kinase in Production of the Polymeric Bioemulsifier Emulsan from the Oil-Degrading Strain Acinetobacter lwoffii RAG-1." Journal of Bacteriology 185, no. 3 (February 1, 2003): 1001–9. http://dx.doi.org/10.1128/jb.185.3.1001-1009.2003.
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ABSTRACT The genes associated with the biosynthesis of the polymeric bioemulsifier emulsan, produced by the oil-degrading Acinetobacter lwoffii RAG-1 are clustered within a 27-kbp region termed the wee cluster. This report demonstrates the involvement of two genes of the wee cluster of RAG-1, wzb and wzc, in emulsan biosynthesis. The two gene products, Wzc and Wzb were overexpressed and purified. Wzc exhibited ATP-dependent autophosphorylating protein tyrosine kinase activity. Wzb was found to be a protein tyrosine phosphatase capable of dephosphorylating the phosphorylated Wzc. Using the synthetic substrate p-nitrophenyl phosphate (PNPP) Wzb exhibited a V max of 12 μmol of PNPP min−1 mg−1 and a Km of 8 mM PNPP at 30°C. The emulsifying activity of mutants lacking either wzb or wzc was 16 and 15% of RAG-1 activity, respectively, suggesting a role for the two enzymes in emulsan production. Phosphorylation of Wzc was found to occur within a cluster of five tyrosine residues at the C terminus. Colonies from a mutant in which these five tyrosine residues were replaced by five phenylalanine residues along with those of a second mutant, which also lacked Wzb, exhibited a highly viscous colony consistency. Emulsan activity of these mutants was 25 and 24% of that of RAG-1, respectively. Neither of these mutants contained cell-associated emulsan. However, they did produce an extracellular high-molecular-mass galactosamine-containing polysaccharide. A model is proposed in which subunit polymerization, translocation and release of emulsan are all associated and coregulated by tyrosine phosphorylation.
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Rosche, Thomas M., Ben Smith, and James D. Oliver. "Evidence for an Intermediate Colony Morphology of Vibrio vulnificus." Applied and Environmental Microbiology 72, no. 6 (June 2006): 4356–59. http://dx.doi.org/10.1128/aem.02937-05.
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ABSTRACT Vibrio vulnificus causes both food-borne disease and wound infections. Most V. vulnificus strains express capsular polysaccharide (CPS), which is required for the virulence of this organism. Under standard growth conditions, CPS expression is lost at a relatively high frequency (10−3 to 10−4), resulting in a switch from an opaque (Op, CPS+) colony morphology to a translucent (Tr, CPS−) colony morphology. The wzb gene, which encodes a phosphatase required for CPS expression, has been proposed to be involved in this switch through a site-specific deletion of the entire gene. In an examination of five strains, we found that the frequency of wzb deletion in Tr colonies varies by strain and therefore does not account for all the Tr colonies that are seen. In addition, we have identified a third, intermediate (Int) colony morphotype, in which the colonies appear less opaque but are not fully translucent. PCR studies have demonstrated that Int colonies still contain the wzb gene, while reverse transcriptase PCR studies have shown that although Int strains retain expression of wzb, in some cases the transcription of wzb is reduced. Int strains switch to a true Tr (wzb negative) morphotype at a very high frequency (nearly 100%) under certain conditions. Finally, Int colonies, which in some cases can easily be mistaken for Tr colonies, have been observed to occasionally revert to Op, while Tr colonies containing a wzb deletion presumably are unable to revert to the encapsulated form.
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LaPointe, Gisele, Daniele Atlan, and Christophe Gilbert. "Characterization and site-directed mutagenesis of Wzb, an O-phosphatase from Lactobacillus rhamnosus." BMC Biochemistry 9, no. 1 (2008): 10. http://dx.doi.org/10.1186/1471-2091-9-10.
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Tiwari, Monalisa, Shruti Panwar, Akansha Kothidar, and Vishvanath Tiwari. "Rational targeting of Wzb phosphatase and Wzc kinase interaction inhibits extracellular polysaccharides synthesis and biofilm formation in Acinetobacter baumannii." Carbohydrate Research 492 (June 2020): 108025. http://dx.doi.org/10.1016/j.carres.2020.108025.
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Govarthanan, Muthusamy, Jung-Hee Park, Loganathan Praburaman, Young-Joo Yi, Min Cho, Hyun Myung, Shanmugam Gnanendra, Seralathan Kamala-Kannan, and Byung-Taek Oh. "Relative Expression of Low Molecular Weight Protein, Tyrosine Phosphatase (Wzb Gene) of Herbaspirillum sp. GW103 Toward Arsenic Stress and Molecular Modeling." Current Microbiology 71, no. 3 (June 6, 2015): 311–16. http://dx.doi.org/10.1007/s00284-015-0850-6.
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Klumpp, Susanne, Jan Hermesmeier, Dagmar Selke, Ralf Baumeister, Roland Kellner, and Josef Krieglstein. "Protein Histidine Phosphatase: A Novel Enzyme with Potency for Neuronal Signaling." Journal of Cerebral Blood Flow & Metabolism 22, no. 12 (December 2002): 1420–24. http://dx.doi.org/10.1097/01.wcb.0000045041.03034.99.
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The importance of reversible phosphorylation for neuronal signaling and cell survival is well recognized. Knowledge in vertebrates, however, is so far limited to O-phosphates from serine, threonine, and tyrosine. The authors describe an enzyme acting on N-phosphates. It is the first protein histidine phosphatase identified in vertebrates. This histidine phosphatase is ubiquitously expressed in mammalian tissues including brain. Characterization and sequencing showed a yet unknown protein with no similarity to other phosphatases. In Caenorhabditis elegans, the homolog of this histidine phosphatase was exclusively expressed in neurons, suggesting a distinct role of reversible histidine phosphorylation in neuronal functions.
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Pettis, Gregg S., and Aheli S. Mukerji. "Structure, Function, and Regulation of the Essential Virulence Factor Capsular Polysaccharide of Vibrio vulnificus." International Journal of Molecular Sciences 21, no. 9 (May 5, 2020): 3259. http://dx.doi.org/10.3390/ijms21093259.
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Vibrio vulnificus populates coastal waters around the world, where it exists freely or becomes concentrated in filter feeding mollusks. It also causes rapid and life-threatening sepsis and wound infections in humans. Of its many virulence factors, it is the V. vulnificus capsule, composed of capsular polysaccharide (CPS), that plays a critical role in evasion of the host innate immune system by conferring antiphagocytic ability and resistance to complement-mediated killing. CPS may also provoke a portion of the host inflammatory cytokine response to this bacterium. CPS production is biochemically and genetically diverse among strains of V. vulnificus, and the carbohydrate diversity of CPS is likely affected by horizontal gene transfer events that result in new combinations of biosynthetic genes. Phase variation between virulent encapsulated opaque colonial variants and attenuated translucent colonial variants, which have little or no CPS, is a common phenotype among strains of this species. One mechanism for generating acapsular variants likely involves homologous recombination between repeat sequences flanking the wzb phosphatase gene within the Group 1 CPS biosynthetic and transport operon. A considerable number of environmental, genetic, and regulatory factors have now been identified that affect CPS gene expression and CPS production in this pathogen.
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Cefalo, Angela D., Jeffery R. Broadbent, and Dennis L. Welker. "The Streptococcus thermophilus protein Wzh functions as a phosphotyrosine phosphatase." Canadian Journal of Microbiology 59, no. 6 (June 2013): 391–98. http://dx.doi.org/10.1139/cjm-2013-0094.
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Amino acid residues that are important for metal binding and catalysis in Gram-positive phosphotyrosine phosphatases were identified in the Wzh protein of Streptococcus thermophilus MR-1C by using sequence comparisons. A His-tagged fusion Wzh protein was purified from Escherichia coli cultures and tested for phosphatase activity against synthetic phosphotyrosine and phosphoserine–threonine peptides. Purified Wzh released 2316.5 ± 138.7 pmol PO4·min−1·μg−1 from phosphotyrosine peptide-1 and 2345.7 ± 135.2 pmol PO4·min−1·μg−1 from phosphotyrosine peptide-2. The presence of the phosphotyrosine phosphatase inhibitor sodium vanadate decreased purified Wzh activity by 45%–50% at 1 mmol·L–1, 74%–84% at 5 mmol·L–1, and by at least 88% at 10 mmol·L–1. Purified Wzh had no detectable activity against the phosphoserine–threonine peptide. These results clearly establish that S. thermophilus MR-1C Wzh functions as a phosphotyrosine phosphatase that could function to remove phosphate groups from proteins involved in exopolysaccharide biosynthesis, including the protein tyrosine kinase Wze and priming glycosyltransferase.
Dissertations / Theses on the topic "Wzb phosphatase"
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Iodice, Domenico. "Construction and characterization of probiotic Lactobacillus rhamnosus GG deletion mutant for extracellular polysaccharide (EPS) biosynthesis regulator." Doctoral thesis, Università di Siena, 2018. http://hdl.handle.net/11365/1037713.
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Lactobacillus rhamnosus GG ATCC 53103 (LGG) is a probiotic microorganism
producing a galactose-rich exopolysaccharide (EPS) surrounding the cell wall
involved in adhesion and biofilm formation. The EPS gene cluster is composed
by 16 genes associated to EPS biosynthesis. The wzb gene is an ortholog of the
Streptococcus pneumoniae cpsB, encoding a protein phosphatase involved in
the regulation of capsule production. In order to study the role of wzb gene in
EPS biosynthesis, a L. rhamnosus GG wzb deletion mutant was constructed.
Deletion of wzb produced a 12 minutes reduction of duplication time during
growth. Deletion mutant strain produced smaller colonies than wild-type strain.
Alcian Blue and India Ink staining denoted a strong reduction of the halo
surrounding cells likely associated to EPS in Δwzb strain. Zeta potential analysis
showed 2 bacterial populations in the Δwzb strain, while a single population was
present in wild type indicating different Zeta potential values and consequently
different electrokinetic properties of bacterial surfaces in the isogenic strains.
Flow cytometry and dot blot analyses were used to assess the binding of Wheat
Germ Agglutinin (WGA) and Chum Salmon Lectin 3 (CSL-3) lectins to the Nacetylglucosamine
and rhamnose residues of EPS. In presence of WGA, 2
bacterial populations were observed in Δwzb strain, while a single population in
wild type strain. In Δwzb strain a strong reduction of CSL-3 binding was
observed. Furthermore, deletion of wzb is responsible of a significant reduction in
biofilm production as estimated by crystal violet coloration. A general reduction of
gene expression level of the EPS gene cluster was observed in Δwzb strain from
the mid exponential to the early stationary growth phases. The present data
reported the first inactivation of wzb gene in L. rhamnosus and the functional
characterization of the Δwzb strain confirmed a role of Wzb phosphatase in EPS
production.
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Huang, Yu-Chie, and 黃愈志. "Structural Studies of Human RNase 7 and Klebsiella pneumoniae Phosphatase Wzb." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/51053237025758269998.
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博士國立臺灣大學
生化科學研究所
97
Chapter 1 Ribonucleases are found widely within living organisms and are thought to play important roles in RNA metabolism, angiogenesis, neurotoxicity, antitumor and antimicrobial activity. In human ribonucleases, antimicrobial activity was found in RNase 3, RNase 5 and RNase 7. The mechanisms of antimicrobial activities remain unclear although they possess similar properties, e.g., high isoelectric point and net positive charge. It is therefore interesting to investigate whether the positively charged residues or epitopes are responsible for the bactericidal activity. Here, we report on the role of cationic residues of human RNase 7 (hRNase 7) in its antimicrobial activity. We found that hRNase 7 is stable in the range of pH 3.5~9.5 and its structure is thermally and chemically stable with a Tm value of 66.4 ℃ and a Cm value of 3.27 M denatured by guanine hydrochloride. NMR structure of hRNase 7 shows that the 22 positively charged residues (18 Lys, 4 Arg) are distributed into three clusters on the surface. Residues in the first cluster including Lys1, Lys3, Lys111 and Lys112, are quite flexible and located near the N-terminus. On the contrary, the other two clusters, one with residues Lys32/Lys35 and the other with Lys96/Arg97/Lys100, are all located on secondary structure regions and are quite rigid. Mutagenesis studies confirmed that residues in the flexible cluster are critical for the bactericidal activity rather than the catalytic residues, such as His15, Lys38, His123, and residues in the other two positively charged clusters. Together, we suggest that hRNase 7 binds to bacterial membrane primarily by using the flexible residues, Lys1, Lys3, Lys111, and Lys112, in the first positively charged cluster and then renders the membrane permeable. Chapter 2 The low molecular weight protein tyrosine phosphatases (LMW-PTPs) in bacteria are ubiquitous regulators of tyrosine phosphorylation. Despite their abundance, the spectrum of functions of LMW-PTPs in prokaryote has yet to be elucidated. Several studies have demonstrated a role of LMW-PTPs in CPS/EPS synthesis and export, as well as in stress resistance. The target protein, LMW-PTPs Wzb, studied in this thesis is from the K. pneumoniae NTUH2044 strain clinically isolated at National Taiwan University Hospital (NTUH). It contains the conserved signature motif of CX5RS known as the P-loop or PTPloop, and an unique Asp residue situated on the DPY-loop of the LMW-PTPs. Our previous study has found that catalytic activity on Wzb_C9S mutant is dramatically reduced or even not seen at all. To ascertain the importance of the conversed residue Cys9 in the catalytic mechanism of Wzb, we expressed and purified unlabeled and isotopically labeled Wzb and Wzb_C9S mutant for structural study. Due to the lack of several cross peaks in NMR spectral of Wzb, we could not determine its structure. In comparison, Wzb_C9S gave much better NMR quality and its 3D NMR solution structure containing a canonical topology of LMW-PTPs with a central four-stranded parallel beta-sheet and five alpha-helices has been solved. Superimposition of 2D HSQC spectra of Wzb and Wzb_C9S reveals that the unobserved cross peaks and cross peaks exhibiting shift changes in Wzb are mostly located in the P-loop and its nearby regions. Backbone dynamics study showed that the residues in the P-loop are moderately rigid. In addition, both Tm and Cm values in Wzb_C9S are higher than those in Wzb. Taken together, we conclude there is a conformational change, especially in the P-loop, between Wzb and Wzb_C9S, with the P-loop in Wzb_C9S apparently more rigid. Due to the change of the rigidity in the P-loop, the Ser9 in C9S mutant is unable to act as a nucleophile to attack the phosphate group, as Cys9 does in Wzb.
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Hong-TsunChang and 張宏存. "iPhos: a web tool to streamline the alkaline phosphatase-assisted LC-MS phosphoproteome investigation." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/7n3cf5.
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碩士國立成功大學
電機工程學系
103
iPhos is a web based software toolkit to facilitate and streamline the work-flow of the alkaline phosphatase-assisted phosphoproteome characterization. Comprehensive characterization of the phosphoproteome in living cells is critical in signal transduction research. But the low abundance of phosphopeptides among the total proteome in cells remains a challenge in mass spectrometry-based proteomic analysis. To overcome the obstacles, an alternative analytic strategy to confidently identify phosphorylated peptides by using the alkaline phosphatase (AP) treatment in combination with high-resolution mass spectrometry was provided by Liao’s group. While the process is applicable, the key integration along the pipeline was mostly done by tedious manual work. In order to be effective and convenient, iPhos not only has a user friendly web interface but also assists the experiment work-flow in data analysis. We further demonstrated the utility of the iPhos toolkit on the data of human metastatic lung cancer cells (CL1-5). In the comparison study of the control group of CL1-5 cell lysates and the treatment group of dasatinib-treated CL1-5 cell lysates, we demonstrated the applicability of the iPhos toolkit and reported the experimental results based on the iPhos-facilitated phosphoproteome investigation. Additionally, we also compared the strategy with pure DDAbased LC-MS/MS phosphoproteome investigation. The results of iPhos-facilitated targeted LC-MS/MS analysis convey more thorough and confident phosphopeptide identification than the results of pure DDA-based analysis. The iPhos software toolkit and sample tutorial data are available online at http://cosbi3.ee.ncku.edu.tw/iPhos/.
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Chao, Ti-chun, and 趙悌均. "PSTPIP2, Proline-Serine-Threonine Phosphatase Interacting Protein 2, a Host Membrane-Deforming Protein, is Critical for Membranous Web Formation in Hepatitis C Virus Replication." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/06552578558701366866.
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Islam, Salim Timo. "Structural and Functional Characterization of O-Antigen Translocation and Polymerization in Pseudomonas aeruginosa PAO1." Thesis, 2013. http://hdl.handle.net/10214/7239.
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Heteropolymeric O antigen (O-Ag)-capped lipopolysaccharide is the principal constituent of the Gram-negative bacterial cell surface. It is assembled via the integral inner membrane (IM) Wzx/Wzy-dependent pathway. In Pseudomonas aeruginosa, Wzx translocates lipid-linked anionic O-Ag subunits from the cytoplasmic to the periplasmic leaflets of the IM, where Wzy polymerizes the subunits to lengths regulated by Wzz1/2. The Wzx and Wzy IM topologies were mapped using random C-terminal-truncation fusions to PhoALacZα, which displays PhoA/LacZ activity dependent upon its subcellular localization. Twelve transmembrane segments (TMS) containing charged residues were identified for Wzx. Fourteen TMS, two sizeable cytoplasmic loops (CL), and two large periplasmic loops (PL3 and PL5 of comparable size) were characterized for Wzy.
Despite Wzy PL3–PL5 sequence homology, these loops were distinguished by respective cationic and anionic charge properties. Site-directed mutagenesis identified functionally-essential Arg residues in both loops. These results led to the proposition of a “catch-and-release” mechanism for Wzy function. The abovementioned Arg residues and intra-Wzy PL3–PL5 sequence homology were conserved among phylogenetically diverse Wzy homologues, indicating widespread potential for the proposed mechanism. Unexpectedly, Wzy CL6 mutations disrupted Wzz1-mediated regulation of shorter O-Ag chains, providing the first evidence for direct Wzy–Wzz interaction.
Mutagenesis studies identified functionally-important charged and aromatic TMS residues localized to either the interior vestibule or TMS bundles in a 3D homology model constructed for Wzx. Substrate-binding or energy-coupling roles were proposed for these residues, respectively. The Wzx interior was found to be cationic, consistent with translocation of anionic O-Ag subunits. To test these hypotheses, Wzx was overexpressed, purified, and reconstituted in proteoliposomes loaded with I−. Common transport coupling ions were introduced to “open” the protein and allow detection of I− flux via reconstituted Wzx. Extraliposomal changes in H+ induced I− flux, while Na+ addition had no effect, suggesting H+-dependent Wzx gating. Putative energy-coupling residue mutants demonstrated defective H+-dependent halide flux. Wzx also mediated H+ uptake as detected through fluorescence shifts from proteoliposomes loaded with pH-sensitive dye. Consequently, Wzx was proposed to function via H+-coupled antiport. In summary, this research has contributed structural and functional knowledge leading to novel mechanistic understandings for O-Ag biosynthesis in bacteria.Bookmarks within the document have been provided for ease of access to a particular section in the body of the thesis. Each entry in the Table of Contents, List of Tables, and List of Figures has been "linked" to its respective position and as such can be clicked for direct access to the entry. Similarly, each in-text Figure or Table reference has been "linked" to its respective figure/table for direct access to the entry.
1.) Canadian Institutes of Health Research (CIHR) Frederick Banting and Charles Best Canada Graduate Scholarship doctoral award, 2.) CIHR Michael Smith Foreign Study Award, 3.) Cystic Fibrosis Canada (CFC) doctoral studentship, 4.) University of Guelph Dean's Tri-Council Scholarship, 5.) Ontario Graduate Scholarship in Science and Technology, 6.) Operating grants to Dr. Joseph S. Lam from CIHR (MOP-14687) and CFC
Books on the topic "Wzb phosphatase"
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Kirchman, David L. Degradation of organic matter. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780198789406.003.0007.
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The aerobic oxidation of organic material by microbes is the focus of this chapter. Microbes account for about 50% of primary production in the biosphere, but they probably account for more than 50% of organic material oxidization and respiration (oxygen use). The traditional role of microbes is to degrade organic material and to release plant nutrients such as phosphate and ammonium as well as carbon dioxide. Microbes are responsible for more than half of soil respiration, while size fractionation experiments show that bacteria are also responsible for about half of respiration in aquatic habitats. In soils, both fungi and bacteria are important, with relative abundances and activity varying with soil type. In contrast, fungi are not common in the oceans and lakes, where they are out-competed by bacteria with their small cell size. Dead organic material, detritus, used by microbes, comes from dead plants and waste products from herbivores. It and associated microbes can be eaten by many eukaryotic organisms, forming a detritus food web. These large organisms also break up detritus into small pieces, creating more surface area on which microbes can act. Microbes in turn need to use extracellular enzymes to hydrolyze large molecular weight compounds, which releases small compounds that can be transported into cells. Fungi and bacteria use a different mechanism, “oxidative decomposition,” to degrade lignin. Organic compounds that are otherwise easily degraded (“labile”) may resist decomposition if absorbed to surfaces or surrounded by refractory organic material. Addition of labile compounds can stimulate or “prime” the degradation of other organic material. Microbes also produce organic compounds, some eventually resisting degradation for thousands of years, and contributing substantially to soil organic material in terrestrial environments and dissolved organic material in aquatic ones. The relationship between community diversity and a biochemical process depends on the metabolic redundancy among members of the microbial community. This redundancy may provide “ecological insurance” and ensure the continuation of key biogeochemical processes when environmental conditions change.
Book chapters on the topic "Wzb phosphatase"
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Sharma, Sunita. "Biosynthesis of the Immunomodulatory Molecule Capsular Polysaccharide A from Bacteroides fragilis." In Biosynthesis [Working Title]. IntechOpen, 2021. http://dx.doi.org/10.5772/intechopen.96937.
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Capsular Polysaccharide A (CPSA) is a polymer of a tetrasaccharide unit found on the surface of the symbiotic gut bacteria Bacteroides fragilis. CPSA has been suggested to be important for maintaining a natural equilibrium between Th1 and Th2 cell levels in the normal immune system of mammals. If this equilibrium is disrupted, the human body can develop different autoimmune disorders. The gene locus responsible for CPSA biosynthesis has been previously identified. The locus was proposed to encode one glycosyl-1-phosphate transferase (WcfS) and three glycosyltransferases (WcfN, -P and -Q), three sugar modifying enzymes (WcfM, WcfR and WcfO), a flippase (Wzx) and a polysaccharide polymerase (Wzy) based on homology tools. A route for the complete biosynthesis of CPSA has been elucidated. The initiating sugar transferase, WcfS has been previously identified and characterized. An in vitro method was used to enzymatically synthesize CPSA, which was assembled on a fluorescent analogue of the native bactoprenyl diphosphate anchor one sugar at a time. Function of the hypothesized pyruvyltransferase WcfO was also determined. This is the first study to characterize a pyruvyltransferase involved in polysaccharide biosynthesis from a prokaryote. The biosynthesis of the polysaccharide was achieved in a single pot, compared to multiple steps involved in chemical synthesis, displaying an enormous leap in the biosynthesis of complex molecules like CPSA.
Conference papers on the topic "Wzb phosphatase"
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Nishi, Toshihiro, Kazunori Naganuma, Yoshihisa Sakai, Masao Asobe, and Shoichi Sudo. "Amplification characteristics of femtosecond optical pulses in short, Er3+-doped phosphate fibers." In OSA Annual Meeting. Washington, D.C.: Optica Publishing Group, 1993. http://dx.doi.org/10.1364/oam.1993.wb.1.
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Xia, Da-Hai, Chengcheng Pan, Shi-Zhe Song, Wei-Xian Jin, Wen-Bin Hu, and Bao-Min Fan. "Covalent surface modification of 2024 aluminum alloy surface by self-assembly dodecyl phosphate film towards corrosion protection." In 1st Corrosion and Materials Degradation Web Conference. Basel, Switzerland: MDPI, 2021. http://dx.doi.org/10.3390/cmdwc2021-10040.
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DAGDAG, Omar, Zaki Safi, Lei Guo, Hamid Erramli, and Mustapha El Gouri. "Assessment of the anticorrosive efficiency of zinc phosphate (ZP) and epoxy resin (DGEBA-DAA) based composite (DGEBA-DAA-ZP) for electrolytic cadmium pre-treated 15CDV6 steel in 3wt% NaCl medium: experimental and computational studies." In 1st Corrosion and Materials Degradation Web Conference. Basel, Switzerland: MDPI, 2021. http://dx.doi.org/10.3390/cmdwc2021-09984.
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