Gene Symbol: waaR
Description: lipopolysaccharide 1,2-glucosyltransferase; UDP-glucose:(glucosyl)LPS alpha-1,2-glucosyltransferase
Alias: ECK3616, JW3601, rfaJ, rfaN, waaJ
Species: Escherichia coli str. K-12 substr. MG1655

Top Publications

  1. Pradel E, Parker C, Schnaitman C. Structures of the rfaB, rfaI, rfaJ, and rfaS genes of Escherichia coli K-12 and their roles in assembly of the lipopolysaccharide core. J Bacteriol. 1992;174:4736-45 pubmed
    ..The third and fourth genes encode proteins of 39,423 and 36,046 Da which are strongly homologous to the RfaI and RfaJ proteins of S. typhimurium. Escherichia coli K-12 restriction fragments carrying these genes complement an S...
  2. Parker C, Kloser A, Schnaitman C, Stein M, Gottesman S, Gibson B. Role of the rfaG and rfaP genes in determining the lipopolysaccharide core structure and cell surface properties of Escherichia coli K-12. J Bacteriol. 1992;174:2525-38 pubmed
    ..A model is presented which relates the deep rough phenotype to the loss of heptose-linked P and PPEA. ..
  3. Taylor C, Goldrick M, Lord L, Roberts I. Mutations in the waaR gene of Escherichia coli which disrupt lipopolysaccharide outer core biosynthesis affect cell surface retention of group 2 capsular polysaccharides. J Bacteriol. 2006;188:1165-8 pubmed
    On the basis of increased resistance to K5 capsule-specific bacteriophage, a waaR transposon mutant defective in the biosynthesis of lipopolysaccharide outer core was isolated...
  4. Shibayama K, Ohsuka S, Sato K, Yokoyama K, Horii T, Ohta M. Four critical aspartic acid residues potentially involved in the catalytic mechanism of Escherichia coli K-12 WaaR. FEMS Microbiol Lett. 1999;174:105-9 pubmed
    Escherichia coli K-12 WaaR is a non-processive alpha-1,2 glucosyltransferase, involved in the synthesis of the R-core of lipopolysaccharide...
  5. Schnaitman C, Parker C, Klena J, Pradel E, Pearson N, Sanderson K, et al. Physical maps of the rfa loci of Escherichia coli K-12 and Salmonella typhimurium. J Bacteriol. 1991;173:7410-1 pubmed
  6. Schnaitman C, Klena J. Genetics of lipopolysaccharide biosynthesis in enteric bacteria. Microbiol Rev. 1993;57:655-82 pubmed
  7. Klena J, Ashford R, Schnaitman C. Role of Escherichia coli K-12 rfa genes and the rfp gene of Shigella dysenteriae 1 in generation of lipopolysaccharide core heterogeneity and attachment of O antigen. J Bacteriol. 1992;174:7297-307 pubmed
    ..All of these studies indicate that the apparent heterogeneity of E. coli K-12 LPS observed on gels is not an artifact but instead a reflection of functional differences among LPS species. ..
  8. 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
    The waaJ, waaT, and waaR genes encode alpha-1,2-glycosyltransferases involved in synthesis of the outer core region of the lipopolysaccharide of Escherichia coli...
  9. Traurig M, Misra R. Identification of bacteriophage K20 binding regions of OmpF and lipopolysaccharide in Escherichia coli K-12. FEMS Microbiol Lett. 1999;181:101-8 pubmed

More Information


  1. Reeves P, Hobbs M, Valvano M, Skurnik M, Whitfield C, Coplin D, et al. Bacterial polysaccharide synthesis and gene nomenclature. Trends Microbiol. 1996;4:495-503 pubmed
    ..We propose a scheme applicable to all species that distinguishes different classes of genes, provides a single name for all genes of a given function and greatly facilitates comparative studies. ..
  2. Roncero C, Casadaban M. Genetic analysis of the genes involved in synthesis of the lipopolysaccharide core in Escherichia coli K-12: three operons in the rfa locus. J Bacteriol. 1992;174:3250-60 pubmed
    ..The genetic organization of this locus seems to be identical in E. coli K-12 and S. typhimurium. ..
  3. Creeger E, Schulte T, Rothfield L. Regulation of membrane glycosyltransferases by the sfrB and rfaH genes of Escherichia coli and Salmonella typhimurium. J Biol Chem. 1984;259:3064-9 pubmed
    ..typhimurium galactosyltransferase. Taken together, the results indicate that the sfrB(rfaH) gene acts as a positive regulatory element in expression of multiple glycosyltransferases in E. coli and S. typhimurium. ..
  4. Austin E, Graves J, Hite L, Parker C, Schnaitman C. Genetic analysis of lipopolysaccharide core biosynthesis by Escherichia coli K-12: insertion mutagenesis of the rfa locus. J Bacteriol. 1990;172:5312-25 pubmed
    ..We speculate that the product of this gene is involved in the attachment of phosphate or phosphorylethanolamine to the core and that it is the lack of one of these substituents which results in the deep rough phenotype. ..
  5. 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
  6. Pradel E, Schnaitman C. Effect of rfaH (sfrB) and temperature on expression of rfa genes of Escherichia coli K-12. J Bacteriol. 1991;173:6428-31 pubmed
    ..In addition, expression of the lacZ fusion to rfaJ was reduced by growth at 42 degrees C, and this correlated with a temperature-induced change in the electrophoretic ..
  7. Klena J, Pradel E, Schnaitman C. Comparison of lipopolysaccharide biosynthesis genes rfaK, rfaL, rfaY, and rfaZ of Escherichia coli K-12 and Salmonella typhimurium. J Bacteriol. 1992;174:4746-52 pubmed
    Analysis of the sequence of a 4.3-kb region downstream of rfaJ revealed four genes...
  8. 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
    The waaJ gene encodes an alpha-1,2-glucosyltransferase involved in the synthesis of the outer core region of the lipopolysaccha-ride of some Escherichia coli and Salmonella isolates...
  9. Klein G, Lindner B, Brade H, Raina S. Molecular basis of lipopolysaccharide heterogeneity in Escherichia coli: envelope stress-responsive regulators control the incorporation of glycoforms with a third 3-deoxy-?-D-manno-oct-2-ulosonic acid and rhamnose. J Biol Chem. 2011;286:42787-807 pubmed publisher
    ..This truncation in ?rseA was ascribed to decreased levels of WaaR glycosyltransferase, which was restored to wild-type levels, including overall LPS composition, upon the ..
  10. Huang H, Liu X, Lv S, Zhong W, Zhang F, Linhardt R. Recombinant Escherichia coli K5 strain with the deletion of waaR gene decreases the molecular weight of the heparosan capsular polysaccharide. Appl Microbiol Biotechnol. 2016;100:7877-85 pubmed publisher
    ..In the heparosan biosynthesis pathway, the gene waaR encoding ?-1-, 2- glycosyltransferase catalyze s the third glucosyl residues linking to the oligosaccharide chain...