Genomes and Genes
Experts and Doctors on escherichia coli in Guelph, Ontario, Canada
Locale: Guelph, Ontario, Canada
Topic: escherichia coli
- Reid A, Whitfield C. 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. J Bacteriol. 2005;187:5470-81 pubmed..These data highlight the importance of Wza-Wzc interactions in group 1 CPS assembly. ..
- Stokes J, French S, Ovchinnikova O, Bouwman C, Whitfield C, Brown E. Cold Stress Makes Escherichia coli Susceptible to Glycopeptide Antibiotics by Altering Outer Membrane Integrity. Cell Chem Biol. 2016;23:267-277 pubmed publisher..These unexpected observations challenge the current understanding of outer membrane permeability, and provide new chemical insights into the susceptibility of E. coli to glycopeptide antibiotics. ..
- Eckford P, Sharom F. The reconstituted Escherichia coli MsbA protein displays lipid flippase activity. Biochem J. 2010;429:195-203 pubmed publisher..The present paper represents the first report of a direct measurement of the lipid flippase activity of purified MsbA in a reconstituted system...
- Mitchell G, Clark M, Lu R, Caswell J. Localization and functional characterization of pulmonary bovine odorant-binding protein. Vet Pathol. 2011;48:1054-60 pubmed publisher..These findings indicate that OBP may inhibit neutrophil recruitment by inflammatory mediators, and they suggest an ability to bind macrophage-derived inflammatory mediators within the airways. ..
- Romantsov T, Battle A, Hendel J, Martinac B, Wood J. Protein localization in Escherichia coli cells: comparison of the cytoplasmic membrane proteins ProP, LacY, ProW, AqpZ, MscS, and MscL. J Bacteriol. 2010;192:912-24 pubmed publisher..Polar localization can be frequent and CL independent (as observed for LacY), frequent and CL dependent (as observed for ProP and MscS), or infrequent (as observed for AqpZ, ProW, and MscL). ..
- Larue K, Ford R, Willis L, Whitfield C. Functional and structural characterization of polysaccharide co-polymerase proteins required for polymer export in ATP-binding cassette transporter-dependent capsule biosynthesis pathways. J Biol Chem. 2011;286:16658-68 pubmed publisher..These experiments add further support for the model of an ABC transporter-PCP-OPX multiprotein complex that functions to export CPS across the cell envelope...
- Gong J, Si W, Forster R, Huang R, Yu H, Yin Y, et al. 16S rRNA gene-based analysis of mucosa-associated bacterial community and phylogeny in the chicken gastrointestinal tracts: from crops to ceca. FEMS Microbiol Ecol. 2007;59:147-57 pubmed..Both Lactobacillus aviarius and Lactobacillus salivarius were the predominant species among lactobacilli. Candidatus division Arthromitus was also abundant in the jejunum and ileum. ..
- Goodridge L, Gallaccio A, Griffiths M. Morphological, host range, and genetic characterization of two coliphages. Appl Environ Microbiol. 2003;69:5364-71 pubmed..The wide host ranges of phages AR1 and LG1 suggest that they may be useful as biocontrol, therapeutic, or diagnostic agents to control and detect the prevalence of E. coli in animals and food...
- Ge L, Seah S. Heterologous expression, purification, and characterization of an l-ornithine N(5)-hydroxylase involved in pyoverdine siderophore biosynthesis in Pseudomonas aeruginosa. J Bacteriol. 2006;188:7205-10 pubmed publisher..The results indicate that the chemical nature of effectors is important for simulation of the NADPH oxidation rate in PvdA...
- Jeong E, Sopher C, Kim I, Lee H. Mutational study of the role of tyrosine-49 in the Saccharomyces cerevisiae xylose reductase. Yeast. 2001;18:1081-9 pubmed..This supports the view that Tyr49 is involved in interaction with the substrate and not the co-factor during catalysis. ..
- Culham D, Lu A, Jishage M, Krogfelt K, Ishihama A, Wood J. The osmotic stress response and virulence in pyelonephritis isolates of Escherichia coli: contributions of RpoS, ProP, ProU and other systems. Microbiology. 2001;147:1657-70 pubmed publisher..The contributions of systems ProP and ProU to urinary tract colonization cannot be definitively assessed until all such systems are identified...
- Culham D, Tripet B, Racher K, Voegele R, Hodges R, Wood J. The role of the carboxyl terminal alpha-helical coiled-coil domain in osmosensing by transporter ProP of Escherichia coli. J Mol Recognit. 2000;13:309-22 pubmed..These data demonstrate that the carboxyl terminal domain of ProP can form a homodimeric alpha-helical coiled-coil with unusual properties. They implicate the C-terminal domain in the osmotic activation of ProP. ..
- Nabavi S, Nellimarla S, Nazar R. Post-transcriptional regulation of the U3 small nucleolar RNA. J Biol Chem. 2008;283:21404-10 pubmed publisher..Precursor processing in vitro and mutational analyses were consistent with this model. ..
- Willis L, Whitfield C. KpsC and KpsS are retaining 3-deoxy-D-manno-oct-2-ulosonic acid (Kdo) transferases involved in synthesis of bacterial capsules. Proc Natl Acad Sci U S A. 2013;110:20753-8 pubmed publisher..KpsS adds the first Kdo residue, and this reaction product is then extended by KpsC. Cross-complementation experiments demonstrate that the E. coli and N. meningitidis protein homologs are functionally conserved. ..
- Kunte H, Crane R, Culham D, Richmond D, Wood J. Protein ProQ influences osmotic activation of compatible solute transporter ProP in Escherichia coli K-12. J Bacteriol. 1999;181:1537-43 pubmed..ProQ may be a structural element that influences the osmotic activation of ProP at a posttranslational level. ..
- Tran A, Trent M, Whitfield C. The LptA protein of Escherichia coli is a periplasmic lipid A-binding protein involved in the lipopolysaccharide export pathway. J Biol Chem. 2008;283:20342-9 pubmed publisher..These results are consistent with LptA playing a chaperone role in the transport of LPS across the periplasm and have implications for possible assembly models. ..
- He C, Post Y, Dony J, Edge T, Patel M, Rochfort Q. A physical descriptive model for predicting bacteria level variation at a dynamic beach. J Water Health. 2016;14:617-29 pubmed publisher..In spite of the complexity and dynamic conditions at the studied beach, the PDM achieved 75% accuracy overall for the five case years examined. ..
- Vadillo Rodriguez V, Schooling S, Dutcher J. In situ characterization of differences in the viscoelastic response of individual gram-negative and gram-positive bacterial cells. J Bacteriol. 2009;191:5518-25 pubmed publisher..coli cells, has been quantified. We expect that our findings will be helpful in increasing the understanding of the structure-property relationships of bacterial cell envelopes. ..
- Miranda M, Choi A, Shi L, Bezerra A, Jung K, Brown L. The photocycle and proton translocation pathway in a cyanobacterial ion-pumping rhodopsin. Biophys J. 2009;96:1471-81 pubmed publisher..We assigned a pair of FTIR bands (positive at 1749 cm(-1) and negative at 1734 cm(-1)) to the protonation and deprotonation, respectively, of these carboxylic acids. ..
- Kozak G, Pearl D, Parkman J, Reid Smith R, Deckert A, Boerlin P. Distribution of sulfonamide resistance genes in Escherichia coli and Salmonella isolates from swine and chickens at abattoirs in Ontario and Québec, Canada. Appl Environ Microbiol. 2009;75:5999-6001 pubmed publisher..Each sul gene was distributed differently across populations, with a significant difference between distribution in commensal E. coli and Salmonella isolates and sul3 restricted mainly to porcine E. coli isolates. ..
- O Connor A, Ziebell K, Poppe C, McEwen S. Verotoxins in commensal Escherichia coli in cattle: the effect of injectable subcutaneous oxytetracycline in addition to in-feed chlortetracycline on prevalence. Epidemiol Infect. 2004;132:77-85 pubmed
- Paiment A, Hocking J, Whitfield C. Impact of phosphorylation of specific residues in the tyrosine autokinase, Wzc, on its activity in assembly of group 1 capsules in Escherichia coli. J Bacteriol. 2002;184:6437-47 pubmed..Finally, dithiobis(succinimidylpropionate) cross-linking was used to confirm that Wzc(CPS) forms complexes in vivo, independent of the phosphorylation state of the protein...
- Yethon J, Whitfield C. Purification and characterization of WaaP from Escherichia coli, a lipopolysaccharide kinase essential for outer membrane stability. J Biol Chem. 2001;276:5498-504 pubmed..These data are the first proof that WaaP is indeed an LPS kinase. Further, site-directed mutagenesis of a predicted catalytic residue suggests that WaaP shares a common mechanism of action with eukaryotic protein kinases. ..
- Yethon J, Vinogradov E, Perry M, Whitfield C. Mutation of the lipopolysaccharide core glycosyltransferase encoded by waaG destabilizes the outer membrane of Escherichia coli by interfering with core phosphorylation. J Bacteriol. 2000;182:5620-3 pubmed..Structural analyses of waaG mutant lipopolysaccharide showed that the cause for this phenotype was a decrease in core phosphorylation, an unexpected side effect of the waaG mutation. ..
- Kerr C, Culham D, Marom D, Wood J. Salinity-dependent impacts of ProQ, Prc, and Spr deficiencies on Escherichia coli cell structure. J Bacteriol. 2014;196:1286-96 pubmed publisher..The effects of ProQ and Prc deficiencies on ProP activity are indirect, reflecting their roles in the maintenance of cell structure. ..
- Makvandi Nejad S, Sheedy C, Veldhuis L, Richard G, Hall J. Selection of single chain variable fragment (scFv) antibodies from a hyperimmunized phage display library for the detection of the antibiotic monensin. J Immunol Methods. 2010;360:103-18 pubmed publisher..IC(50) values ranged from 0.031 and 231 microM. A cross-reactivity assay against salinomycin, lasalocid A, kanamycin and ampicillin revealed that the two best binders were highly specific to monensin. ..
- Murphy C, Reid Smith R, Boerlin P, Weese J, Prescott J, Janecko N, et al. Escherichia coli and selected veterinary and zoonotic pathogens isolated from environmental sites in companion animal veterinary hospitals in southern Ontario. Can Vet J. 2010;51:963-72 pubmed..There is an environmental reservoir of pathogens in veterinary hospitals; therefore, additional studies are required to characterize risk factors associated with HAI in companion animals, including the role of the environment. ..
- Schmied J, Rupa P, Garvie S, Wilkie B. Immune response phenotype of allergic versus clinically tolerant pigs in a neonatal swine model of allergy. Vet Immunol Immunopathol. 2013;154:17-24 pubmed publisher..Therefore, measurement of allergen-specific IgG, IgG1 and/or IgE activity and evaluation of late-phase ID ST may be useful in identifying allergic IR phenotypes in swine models of food allergy, which may be extended toward human use. ..
- Culham D, Vernikovska Y, Tschowri N, Keates R, Wood J, Boggs J. Periplasmic loops of osmosensory transporter ProP in Escherichia coli are sensitive to osmolality. Biochemistry. 2008;47:13584-93 pubmed publisher..They therefore constitute the first direct evidence of an osmotically induced conformational change associated with osmosensing by a transporter. ..
- Leipold M, Vinogradov E, Whitfield C. Glycosyltransferases involved in biosynthesis of the outer core region of Escherichia coli lipopolysaccharides exhibit broader substrate specificities than is predicted from lipopolysaccharide structures. J Biol Chem. 2007;282:26786-92 pubmed..These results illustrate the differences in behavior between closely related glycosyltransferase enzymes involved in the synthesis of similar glycoconjugates and have implications for glycoengineering applications. ..
- Scheurwater E, Pfeffer J, Clarke A. Production and purification of the bacterial autolysin N-acetylmuramoyl-L-alanine amidase B from Pseudomonas aeruginosa. Protein Expr Purif. 2007;56:128-37 pubmed..Four separate assays involving zymography, light scattering, HPLC and MALDI-TOF mass spectrometry were used to confirm the activity of the protein as an N-acetylmuramoyl-L-alanine amidase. ..
- Dodgson C, Amor P, Whitfield C. Distribution of the rol gene encoding the regulator of lipopolysaccharide O-chain length in Escherichia coli and its influence on the expression of group I capsular K antigens. J Bacteriol. 1996;178:1895-902 pubmed..Collectively, these results suggested that group IA K(LPS) is also synthesized by a Rol-dependent pathway and that the typically short oligosaccharide K(LPS) results from the absence of Rol activity in these strains. ..
- Heinrichs D, Monteiro M, Perry M, Whitfield C. The assembly system for the lipopolysaccharide R2 core-type of Escherichia coli is a hybrid of those found in Escherichia coli K-12 and Salmonella enterica. Structure and function of the R2 WaaK and WaaL homologs. J Biol Chem. 1998;273:8849-59 pubmed..Results of complementation analyses of E. coli K-12 and F632 waaL mutants suggest that structural differences between the WaaL proteins play a role in recognition of, and interaction with, terminal lipopolysaccharide core moieties. ..
- Heinrichs D, Yethon J, Whitfield C. Molecular basis for structural diversity in the core regions of the lipopolysaccharides of Escherichia coli and Salmonella enterica. Mol Microbiol. 1998;30:221-32 pubmed
- Newton D, Creuzenet C, Mangroo D. Formylation is not essential for initiation of protein synthesis in all eubacteria. J Biol Chem. 1999;274:22143-6 pubmed..Therefore, the dogma that eubacteria require formylation of the initiator methionyl-tRNA for initiation of protein synthesis may have been an invalid generalization of results obtained with E. coli. ..
- Wugeditsch T, Paiment A, Hocking J, Drummelsmith J, Forrester C, Whitfield C. Phosphorylation of Wzc, a tyrosine autokinase, is essential for assembly of group 1 capsular polysaccharides in Escherichia coli. J Biol Chem. 2001;276:2361-71 pubmed..Regulation by a post-translational phosphorylation event represents a new dimension in the assembly of bacterial cell-surface polysaccharides. ..
- Franklin K, Clarke A. Overexpression and characterization of the chromosomal aminoglycoside 2'-N-acetyltransferase of Providencia stuartii. Antimicrob Agents Chemother. 2001;45:2238-44 pubmed..No correlation was found between these kinetic parameters and MICs determined for P. stuartii PR50 expressing the 2'-N-acetyltransferase, suggesting that its true in vivo function is not as a resistance factor...
- Ly A, Henderson J, Lu A, Culham D, Wood J. Osmoregulatory systems of Escherichia coli: identification of betaine-carnitine-choline transporter family member BetU and distributions of betU and trkG among pathogenic and nonpathogenic isolates. J Bacteriol. 2004;186:296-306 pubmed..Thus, BetU and TrkG contribute, with other systems, to the osmoregulatory capacity of the species E. coli, but they are not characteristic of a particular phylogenetic group or pathotype...
- Eckford P, Sharom F. Functional characterization of Escherichia coli MsbA: interaction with nucleotides and substrates. J Biol Chem. 2008;283:12840-50 pubmed publisher..25-50 microm. This study represents the first use of fluorescence approaches to estimate MsbA binding affinities for nucleotides and putative transport substrates...
- Leipold M, Kaniuk N, Whitfield C. The C-terminal Domain of the Escherichia coli WaaJ glycosyltransferase is important for catalytic activity and membrane association. J Biol Chem. 2007;282:1257-64 pubmed..Deletions removing 20 or more residues resulted in a protein showing no detectable in vitro activity. Therefore, the C-terminal domain of WaaJ plays a critical role in enzyme function. ..
- Legaree B, Adams C, Clarke A. Overproduction of penicillin-binding protein 2 and its inactive variants causes morphological changes and lysis in Escherichia coli. J Bacteriol. 2007;189:4975-83 pubmed..coli MHD79, a strain lacking six lytic transglycosylases. A possible interaction between the N-terminal domain of PBP 2 and lytic transglycosylases in vivo through the formation of multienzyme complexes is discussed. ..
- Romantsov T, Helbig S, Culham D, Gill C, Stalker L, Wood J. Cardiolipin promotes polar localization of osmosensory transporter ProP in Escherichia coli. Mol Microbiol. 2007;64:1455-65 pubmed..coli cells. The polar localization of ProP was independent of its expression level but correlated with the proportion and polar localization of CL. Association with CL (and not PG) may be required for polar ProP localization. ..
- Moynihan P, Clarke A. O-acetylation of peptidoglycan in gram-negative bacteria: identification and characterization of peptidoglycan O-acetyltransferase in Neisseria gonorrhoeae. J Biol Chem. 2010;285:13264-73 pubmed publisher..gonorrhoeae, and other gram-negative bacteria, requires a two component system. ..
- Silphaduang U, Hincke M, Nys Y, Mine Y. Antimicrobial proteins in chicken reproductive system. Biochem Biophys Res Commun. 2006;340:648-55 pubmed..The discovery of antimicrobial histones in chicken reproductive system provides further evidence that histones may play a role in innate immunity against microorganisms in a wide range of animal species...
- Nesper J, Hill C, Paiment A, Harauz G, Beis K, Naismith J, et al. Translocation of group 1 capsular polysaccharide in Escherichia coli serotype K30. Structural and functional analysis of the outer membrane lipoprotein Wza. J Biol Chem. 2003;278:49763-72 pubmed..Chemical cross-linking of intact cells suggested formation of a transmembrane complex minimally containing Wza and the inner membrane tyrosine autokinase Wzc. ..
- Siarheyeva A, Sharom F. The ABC transporter MsbA interacts with lipid A and amphipathic drugs at different sites. Biochem J. 2009;419:317-28 pubmed publisher..One is a high affinity binding site for the physiological substrate, lipid A, and the other site interacts with drugs with comparable affinity. Thus MsbA may function as both a lipid flippase and a multidrug transporter...
- Kabaroff L, Rodriguez A, Quinton M, Boermans H, Karrow N. Assessment of the ovine acute phase response and hepatic gene expression in response to Escherichia coli endotoxin. Vet Immunol Immunopathol. 2006;113:113-24 pubmed
- Yang Y, Griffiths M. Comparative persistence of subgroups of F-specific RNA phages in river water. Appl Environ Microbiol. 2013;79:4564-7 pubmed publisher..Thus, the characteristics of water should be taken into consideration and the results should be carefully interpreted when F+ RNA phages are used for microbial source tracking. ..
- Kant P, Liu W, Pauls K. PDC1, a corn defensin peptide expressed in Escherichia coli and Pichia pastoris inhibits growth of Fusarium graminearum. Peptides. 2009;30:1593-9 pubmed publisher..The data presented here suggest that the defensin PDC1 peptide of corn could be effectively used to restrict the disease caused by F. graminearum. ..
- Parks R, Evans D. Effect of marker distance and orientation on recombinant formation in poxvirus-infected cells. J Virol. 1991;65:1263-72 pubmed
- King J, Berry S, Clarke B, Morris R, Whitfield C. Lipopolysaccharide O antigen size distribution is determined by a chain extension complex of variable stoichiometry in Escherichia coli O9a. Proc Natl Acad Sci U S A. 2014;111:6407-12 pubmed publisher..Our work highlights limitations of previous models and provides new insight into the mechanisms of length control in polysaccharide biosynthesis. ..
- Racher K, Culham D, Wood J. Requirements for osmosensing and osmotic activation of transporter ProP from Escherichia coli. Biochemistry. 2001;40:7324-33 pubmed..Two poly(ethylene glycol)s, PEG 150 and PEG 200, were membrane-permeant and did not cause liposome shrinkage, but they did partially activate ProP-(His)6. ..
- Pouget J, Coutinho F, Reid Smith R, Boerlin P. Characterization of bla(SHV) genes on plasmids from Escherichia coli and Salmonella enterica isolates from Canadian food animals (2006-2007). Appl Environ Microbiol. 2013;79:3864-6 pubmed publisher..Eighteen were on plasmids of the incI1 (n = 15), incP (n = 2), and incFIB (n = 1) incompatibility groups. These plasmids were all transferable by conjugation between E. coli and S. enterica. ..
- Cottrill M, Golovan S, Phillips J, Forsberg C. Inositol phosphatase activity of the Escherichia coli agp-encoded acid glucose-1-phosphatase. Can J Microbiol. 2002;48:801-9 pubmed..D-Ins(1,2,4,5)P4, D/L-Ins(1,4,5,6)P4 and D/L-Ins(1,2,4,6)P4, respectively. These data support the contention that Agp is a 3-phosphatase. ..
- Clarke B, Richards M, Greenfield L, Hou D, Lowary T, Whitfield C. In vitro reconstruction of the chain termination reaction in biosynthesis of the Escherichia coli O9a O-polysaccharide: the chain-length regulator, WbdD, catalyzes the addition of methyl phosphate to the non-reducing terminus of the growing glycan. J Biol Chem. 2011;286:41391-401 pubmed publisher
- Culham D, Henderson J, Crane R, Wood J. Osmosensor ProP of Escherichia coli responds to the concentration, chemistry, and molecular size of osmolytes in the proteoliposome lumen. Biochemistry. 2003;42:410-20 pubmed..8-1.8 nm). These data suggest that ProP-(His)(6) responds to osmotically induced changes in both cytoplasmic K(+) levels and the concentration of cytoplasmic macromolecules. ..
- Rahn A, Whitfield C. Transcriptional organization and regulation of the Escherichia coli K30 group 1 capsule biosynthesis (cps) gene cluster. Mol Microbiol. 2003;47:1045-60 pubmed..However, the Rcs system can potentially influence levels of capsular polysaccharide production by increasing galF transcription and influencing the available pool of biosynthetic precursors. ..
- Whitfield C. Biosynthesis and assembly of capsular polysaccharides in Escherichia coli. Annu Rev Biochem. 2006;75:39-68 pubmed..These systems have an impact on both a general understanding of membrane trafficking in bacteria and on bacterial pathogenesis...