keyword
MENU ▼
Read by QxMD icon Read
search

Wzx flippase

keyword
https://www.readbyqxmd.com/read/27084765/functional-and-bioinformatics-analysis-of-an-exopolysaccharide-related-gene-epsn-from-lactobacillus-kefiranofaciens-zw3
#1
Jingrui Wang, Wei Tang, Yongna Zheng, Zhuqing Xing, Yanping Wang
A novel lactic acid bacteria strain Lactobacillus kefiranofaciens ZW3 exhibited the characteristics of high production of exopolysaccharide (EPS). The epsN gene, located in the eps gene cluster of this strain, is associated with EPS biosynthesis. Bioinformatics analysis of this gene was performed. The conserved domain analysis showed that the EpsN protein contained MATE-Wzx-like domains. Then the epsN gene was amplified to construct the recombinant expression vector pMG36e-epsN. The results showed that the EPS yields of the recombinants were significantly improved...
September 2016: Archives of Microbiology
https://www.readbyqxmd.com/read/25837817/inefficient-translocation-of-a-truncated-o-unit-by-a-salmonella-wzx-affects-both-o-antigen-production-and-cell-growth
#2
Michael A Liu, Thomas L Stent, Yaoqin Hong, Peter R Reeves
Bacterial Wzx flippases translocate (flip) short oligosaccharide repeat units (O units) across the inner membrane into the periplasm, which is a critical step in the assembly of many O antigens, capsules and other surface polysaccharides. There is enormous diversity in O antigens and capsules in particular, even within species. Wzx proteins are similarly diverse, but it has been widely accepted that they have significant specificity only for the first sugar of an O unit. In this study, we analysed the Wzx from the Salmonella enterica group C2 O antigen gene cluster, which is a unique and divergent member of a set of gene clusters that produce galactose-initiated O antigens...
May 2015: FEMS Microbiology Letters
https://www.readbyqxmd.com/read/25664526/escherichia-coli-o-antigen-gene-clusters-of-serogroups-o62-o68-o131-o140-o142-and-o163-dna-sequences-and-similarity-between-o62-and-o68-and-pcr-based-serogrouping
#3
Yanhong Liu, Xianghe Yan, Chitrita DebRoy, Pina M Fratamico, David S Needleman, Robert W Li, Wei Wang, Liliana Losada, Lauren Brinkac, Diana Radune, Magaly Toro, Narasimha Hegde, Jianghong Meng
The DNA sequence of the O-antigen gene clusters of Escherichia coli serogroups O62, O68, O131, O140, O142, and O163 was determined, and primers based on the wzx (O-antigen flippase) and/or wzy (O-antigen polymerase) genes within the O-antigen gene clusters were designed and used in PCR assays to identify each serogroup. Specificity was tested with E. coli reference strains, field isolates belonging to the target serogroups, and non-E. coli bacteria. The PCR assays were highly specific for the respective serogroups; however, the PCR assay targeting the O62 wzx gene reacted positively with strains belonging to E...
2015: Biosensors
https://www.readbyqxmd.com/read/25358682/synthesis-of-bacterial-polysaccharides-via-the-wzx-wzy-dependent-pathway
#4
REVIEW
Salim T Islam, Joseph S Lam
The surfaces of bacteria mediate a multitude of functions in the environment and in an infected host, including adhesion to both biotic and abiotic substrata, motility, immune system interaction and (or) activation, biofilm formation, and cell-cell communication, with many of these features directly influenced by cell-surface glycans. In both Gram-negative and Gram-positive bacteria, the majority of cell-surface polysaccharides are produced via the Wzx/Wzy-dependent assembly pathway; these glycans include heteropolymeric O-antigen, enterobacterial common antigen, exopolysaccharide, spore coat, and capsule in diverse bacteria...
November 2014: Canadian Journal of Microbiology
https://www.readbyqxmd.com/read/25211341/mutation-of-a-salmonella-serogroup-c1-specific-gene-abrogates-o7-antigen-biosynthesis-and-triggers-nacl-dependent-motility-deficiency
#5
Xiujuan Zhou, Bin Liu, Chunlei Shi, Xianming Shi
Several molecular detection marker genes specific for a number of individual Salmonella serogroups have been recently identified in our lab by comparative genomics for the genotyping of diverse serogroups. To further understand the correlation between serotype and genotype, the function of a Salmonella serogroup-C1-specific gene (SC_2092) was analyzed in this study. It was indicated from the topological prediction using the deduced amino acid sequence of SC_2092 that this putative protein was highly similar to the confirmed Wzx flippases...
2014: PloS One
https://www.readbyqxmd.com/read/24023388/proton-dependent-gating-and-proton-uptake-by-wzx-support-o-antigen-subunit-antiport-across-the-bacterial-inner-membrane
#6
Salim T Islam, Paul D W Eckford, Michelle L Jones, Timothy Nugent, Christine E Bear, Christian Vogel, Joseph S Lam
Wzx flippases are crucial for bacterial cell surface polysaccharide assembly as they transport undecaprenyl pyrophosphate-linked sugar repeat units from the cytoplasmic to the periplasmic leaflets of the inner membrane (IM) for final assembly. Our recently reported three-dimensional (3D) model structure of Wzx from Pseudomonas aeruginosa PAO1 (WzxPa) displayed a cationic internal vestibule and functionally essential acidic amino acids within transmembrane segment bundles. Herein, we examined the intrinsic transport function of WzxPa following its purification and reconstitution in phospholipid liposomes...
September 10, 2013: MBio
https://www.readbyqxmd.com/read/23416996/genetic-analysis-of-capsular-polysaccharide-synthesis-gene-clusters-from-all-serotypes-of-streptococcus-suis-potential-mechanisms-for-generation-of-capsular-variation
#7
Masatoshi Okura, Daisuke Takamatsu, Fumito Maruyama, Takashi Nozawa, Ichiro Nakagawa, Makoto Osaki, Tsutomu Sekizaki, Marcelo Gottschalk, Yumi Kumagai, Shigeyuki Hamada
Streptococcus suis strains are classified into 35 serotypes on the basis of the antigenicity of their capsular polysaccharides (CPs). CP synthesis genes are known to be clustered on the chromosome (cps gene cluster). The entire cps gene clusters of S. suis have so far been sequenced in 15 serotypes and found to be located between orfZ and aroA. In this study, to provide comprehensive information about S. suis CPs, we sequenced the entire cps gene clusters of the remaining serotypes and analyzed the complete set of S...
April 2013: Applied and Environmental Microbiology
https://www.readbyqxmd.com/read/23163869/structural-serological-and-genetic-characterization-of-the-o-antigen-of-providencia-alcalifaciens-o40
#8
Olga G Ovchinnikova, Bin Liu, Dan Guo, Nina A Kocharova, Magdalena Bialczak-Kokot, Alexander S Shashkov, Lu Feng, Antoni Rozalski, Lei Wang, Yuriy A Knirel
The O-polysaccharide chain of the lipopolysaccharide (O-antigen) on the bacterial cell surface is one of the most structurally variable cell components and serves as a basis for serotyping of Gram-negative bacteria, including human opportunistic pathogens of the genus Providencia. In this work, the O-antigen of Providencia alcalifaciens O40 was obtained by mild acid degradation of the isolated lipopolysaccharide and studied by chemical methods and high-resolution NMR spectroscopy. The following structure of the O-polysaccharide was established: →4)-β-D-Quip3NFo-(1→3)-α-D-Galp-(1→3)-β-D-GlcpA-(1→3)-β-D-GalpNAc-(1→, where GlcA stands for glucuronic acid and Qui3NFo for 3,6-dideoxy-3-formamidoglucose...
December 2012: FEMS Immunology and Medical Microbiology
https://www.readbyqxmd.com/read/23016929/wzx-flippase-mediated-membrane-translocation-of-sugar-polymer-precursors-in-bacteria
#9
REVIEW
Salim T Islam, Joseph S Lam
Bacterial cell surface polysaccharides confer resistance to external stress and promote survival in biotic and abiotic environments. Glycan assembly often occurs at the periplasmic leaflet of the inner membrane (IM) from undecaprenyl pyrophosphate (UndPP)-linked polysaccharide units via the Wzx/Wzy-dependent pathway. Wzx is an integral IM protein found in Gram-negative and Gram-positive bacteria that mediates IM translocation of UndPP-linked sugar repeats from the cytoplasmic to the periplasmic leaflet; interaction of Wzx with other assembly proteins is indirectly supported by genetic evidence...
April 2013: Environmental Microbiology
https://www.readbyqxmd.com/read/22966833/structural-serological-and-genetic-characterization-of-the-o-antigen-of-providencia-alcalifaciens-o40
#10
Olga G Ovchinnikova, Bin Liu, Dan Guo, Nina A Kocharova, Magdalena Bialczak-Kokot, Alexander S Shashkov, Lu Feng, Antoni Rozalski, Lei Wang, Yuriy A Knirel
The O-polysaccharide chain of the lipopolysaccharide (O-antigen) on the bacterial cell surface is one of the most structurally variable cell components and serves as a basis for serotyping of Gram-negative bacteria, including human opportunistic pathogens of the genus Providencia. In this work, the O-antigen of Providencia alcalifaciens O40 was obtained by mild acid degradation of the isolated lipopolysaccharide and studied by chemical methods and high-resolution NMR spectroscopy. The following structure of the O-polysaccharide was established: →4)-β-d-Quip3NFo-(1→3)-α-d-Galp-(1→3)-β-d-GlcpA-(1→3)-β-d-GalpNAc-(1→, where GlcA stands for glucuronic acid and Qui3NFo for 3,6-dideoxy-3-formamidoglucose...
September 12, 2012: FEMS Immunology and Medical Microbiology
https://www.readbyqxmd.com/read/22750201/aglr-is-required-for-addition-of-the-final-mannose-residue-of-the-n-linked-glycan-decorating-the-haloferax-volcanii-s-layer-glycoprotein
#11
Lina Kaminski, Ziqiang Guan, Mehtap Abu-Qarn, Zvia Konrad, Jerry Eichler
BACKGROUND: Recent studies of Haloferax volcanii have begun to elucidate the steps of N-glycosylation in Archaea, where this universal post-translational modification remains poorly described. In Hfx. volcanii, a series of Agl proteins catalyzes the assembly and attachment of a N-linked pentasaccharide to the S-layer glycoprotein. Although roles have been assigned to the majority of Agl proteins, others await description. In the following, the contribution of AglR to N-glycosylation was addressed...
October 2012: Biochimica et Biophysica Acta
https://www.readbyqxmd.com/read/22554073/a-cationic-lumen-in-the-wzx-flippase-mediates-anionic-o-antigen-subunit-translocation-in-pseudomonas-aeruginosa-pao1
#12
Salim T Islam, Robert J Fieldhouse, Erin M Anderson, Véronique L Taylor, Robert A B Keates, Robert C Ford, Joseph S Lam
Heteropolymeric B-band O-antigen (O-Ag) biosynthesis in Pseudomonas aeruginosa PAO1 follows the Wzy-dependent pathway, beginning with translocation of undecaprenyl pyrophosphate-linked anionic O-Ag subunits (O units) from the inner to the outer leaflets of the inner membrane (IM). This translocation is mediated by the integral IM flippase Wzx. Through experimentally based and unbiased topological mapping, our group previously observed that Wzx possesses many charged and aromatic amino acid residues within its 12 transmembrane segments (TMS)...
June 2012: Molecular Microbiology
https://www.readbyqxmd.com/read/21548768/detection-of-shiga-toxin-producing-escherichia-coli-o26-o45-o103-o111-o113-o121-o145-and-o157-serogroups-by-multiplex-polymerase-chain-reaction-of-the-wzx-gene-of-the-o-antigen-gene-cluster
#13
Chitrita DebRoy, Elisabeth Roberts, Angela M Valadez, Edward G Dudley, Catherine N Cutter
O-antigens on the surface of Escherichia coli are important virulence factors that are targets of both the innate and adaptive immune system and play a major role in pathogenicity. O-antigens that are responsible for antigenic specificity of the strain determine the O-serogroup. E. coli O26, O45, O103, O111, O113, O121, O145, and O157 have been the most commonly identified O-serogroups associated with Shiga toxin-producing E. coli (STEC) implicated in outbreaks of human illness all over the world. A multiplex polymerase chain reaction assay was developed to simultaneously detect the eight STEC O-serogroups targeting the wzx (O-antigen-flippase) genes of all O-antigen gene clusters...
May 2011: Foodborne Pathogens and Disease
https://www.readbyqxmd.com/read/20871101/analogies-and-homologies-in-lipopolysaccharide-and-glycoprotein-biosynthesis-in-bacteria
#14
REVIEW
Isabelle Hug, Mario F Feldman
Bacteria generate and attach countless glycan structures to diverse macromolecules. Despite this diversity, the mechanisms of glycoconjugate biosynthesis are often surprisingly similar. The focus of this review is on the commonalities between lipopolysaccharide (LPS) and glycoprotein assembly pathways and their evolutionary relationship. Three steps that are essential for both pathways are completed by membrane proteins. These include the initiation of glycan assembly through the attachment of a first sugar residue onto the lipid carrier undecaprenyl pyrophosphate, the translocation across the plasma membrane and the final transfer onto proteins or lipid A-core...
February 2011: Glycobiology
https://www.readbyqxmd.com/read/20829291/twenty-eight-divergent-polysaccharide-loci-specifying-within-and-amongst-strain-capsule-diversity-in-three-strains-of-bacteroides-fragilis
#15
Sheila Patrick, Garry W Blakely, Simon Houston, Jane Moore, Valerie R Abratt, Marcelo Bertalan, Ana M Cerdeño-Tárraga, Michael A Quail, Nicola Corton, Craig Corton, Alexandra Bignell, Andrew Barron, Louise Clark, Stephen D Bentley, Julian Parkhill
Comparison of the complete genome sequence of Bacteroides fragilis 638R, originally isolated in the USA, was made with two previously sequenced strains isolated in the UK (NCTC 9343) and Japan (YCH46). The presence of 10 loci containing genes associated with polysaccharide (PS) biosynthesis, each including a putative Wzx flippase and Wzy polymerase, was confirmed in all three strains, despite a lack of cross-reactivity between NCTC 9343 and 638R surface PS-specific antibodies by immunolabelling and microscopy...
November 2010: Microbiology
https://www.readbyqxmd.com/read/20824106/membrane-topology-mapping-of-the-o-antigen-flippase-wzx-polymerase-wzy-and-ligase-waal-from-pseudomonas-aeruginosa-pao1-reveals-novel-domain-architectures
#16
Salim T Islam, Véronique L Taylor, Meng Qi, Joseph S Lam
Biosynthesis of B-band lipopolysaccharide (LPS) in Pseudomonas aeruginosa follows the Wzy-dependent pathway, requiring the integral inner membrane proteins Wzx (O-antigen [O-Ag] flippase), Wzy (O-Ag polymerase), and WaaL (O-Ag ligase). For an important first step in deciphering the mechanisms of LPS assembly, we set out to map the membrane topology of these proteins. Random and targeted 3'wzx, wzy, and waaL truncations were fused to a phoA-lacZalpha dual reporter capable of displaying both alkaline phosphatase and beta-galactosidase activity...
August 24, 2010: MBio
https://www.readbyqxmd.com/read/20638049/structural-and-genetic-characterization-of-the-o-antigen-of-salmonella-enterica-o56-containing-a-novel-derivative-of-4-amino-4-6-dideoxy-d-glucose
#17
Andrei V Perepelov, Bin Liu, Sergei D Shevelev, Sof'ya N Senchenkova, Bo Hu, Alexander S Shashkov, Lu Feng, Yuriy A Knirel, Lei Wang
Based on the O-antigens (O-polysaccharides), one of the most variable cell constituents, 46 O-serogroups have been recognized in the Kauffmann-White serotyping scheme for Salmonella enterica. In this work, the structure of the O-polysaccharide and the genetic organization of the O-antigen gene cluster of S. enterica O56 were investigated. As judged by sugar and methylation analyses, along with NMR spectroscopic data, the O-polysaccharide has a linear tetrasaccharide O-unit, which consists of one residue each of d-ribofuranose, N-acetyl-d-glucosamine, N-acetyl-d-galactosamine, and a novel sugar derivative, 4-(N-acetyl-l-seryl)amino-4,6-dideoxy-d-glucose (d-Qui4NSerAc)...
September 3, 2010: Carbohydrate Research
https://www.readbyqxmd.com/read/20510395/structural-and-genetic-characterization-of-the-o-antigen-of-escherichia-coli-o161-containing-a-derivative-of-a-higher-acidic-diamino-sugar-legionaminic-acid
#18
Xiaomin Li, Andrei V Perepelov, Quan Wang, Sof'ya N Senchenkova, Bin Liu, Sergei D Shevelev, Xi Guo, Alexander S Shashkov, Wei Chen, Lei Wang, Yuriy A Knirel
The O-antigen is an essential component of lipopolysaccharide on the surface of Gram-negative bacteria and plays an important role in its pathogenicity. Composition and structure of the O-antigens of Escherichia coli are highly diverse mainly due to genetic variations in the O-antigen gene cluster. In this work, the chemical structure and the gene cluster of the O-antigen of E. coli O161 were studied. Chemical degradations, sugar analyses, and NMR spectroscopy showed that the O161 antigen possesses a trisaccharide O-repeating unit containing a 5-N-acetyl-7-N-(d-alanyl) derivative of 5,7-diamino-3,5,7,9-tetradeoxy-d-glycero-d-galacto-non-2-ulosonic (legionaminic) acid (Leg5Ac7Ala) and having the following structure: The O-antigen gene cluster of E...
July 19, 2010: Carbohydrate Research
https://www.readbyqxmd.com/read/20453897/escherichia-coli-serogroup-o2-and-o28ac-o-antigen-gene-cluster-sequences-and-detection-of-pathogenic-e-coli-o2-and-o28ac-by-pcr
#19
Pina M Fratamico, Xianghe Yan, Yanhong Liu, Chitrita DebRoy, Brian Byrne, Aine Monaghan, Seamus Fanning, Declan Bolton
The O-antigen gene clusters of Escherichia coli serogroups O2 and O28ac were sequenced, and PCR assays were developed to identify strains belonging to these 2 serogroups. Sixteen and 8 open reading frames were mapped to these loci in E. coli O2:H4 U 9-41 and E. coli O28ac:H25 96-3286, respectively. The wzx (O-antigen flippase) and wzy (O-antigen polymerase) genes in the E. coli O2 and O28ac O-antigen gene clusters were selected as targets for PCR assays for their identification. PCR assays targeting the wzx and wzy genes were specific for these serogroups, with one exception...
April 2010: Canadian Journal of Microbiology
https://www.readbyqxmd.com/read/20075111/new-enterovirulent-escherichia-coli-serogroup-64474-showing-antigenic-and-genotypic-relationships-to-shigella-boydii-16
#20
Armando Navarro, Carlos Eslava, Luis Manuel Perea, Alma Inzunza, Gabriela Delgado, Rosario Morales-Espinosa, Thomas Cheasty, Alejandro Cravioto
Studies based on the analysis of housekeeping genes indicate that Escherichia coli and all Shigella species, except for Shigella boydii type 13, belong to a single species. This study analysed the phenotypic and genotypic characteristics of 23 E. coli strains isolated in different countries from faecal specimens taken from children with diarrhoea. Strains were identified using the VITEK system and typed with rabbit sera obtained against 186 somatic and 53 flagellar E. coli antigens and against 45 Shigella somatic antigens...
April 2010: Journal of Medical Microbiology
keyword
keyword
59683
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"