Analysis of the G93E mutant allele of KpsM, the membrane component of an ABC transporter involved in polysialic acid translocation in Escherichia coli K1

FEMS Microbiol Lett. 1997 Nov 15;156(2):217-22. doi: 10.1111/j.1574-6968.1997.tb12730.x.


KpsM is an integral membrane protein involved in the translocation of the polysialic acid capsule of Escherichia coli K1. The kpsMG93E allele is a point mutation in the first cytoplasmic loop (Cl) of KpsM which partially disrupts translocation of the capsule. While producing polymer of wild-type length, strains harboring the G93E allele exhibit a decreased production of capsular polymer and a reduced rate of polymer translocation to the cell surface.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • ATP-Binding Cassette Transporters / genetics*
  • Alleles
  • Antigens, Bacterial*
  • Bacterial Capsules / chemistry
  • Bacterial Capsules / metabolism
  • Biological Transport / genetics
  • Cell Membrane / chemistry
  • Cell Membrane / metabolism
  • Escherichia coli / genetics*
  • Escherichia coli / metabolism
  • Mutation
  • Polysaccharides / metabolism
  • Polysaccharides, Bacterial / genetics*
  • Polysaccharides, Bacterial / metabolism
  • Sialic Acids / metabolism*


  • ATP-Binding Cassette Transporters
  • Antigens, Bacterial
  • Polysaccharides
  • Polysaccharides, Bacterial
  • Sialic Acids
  • capsular polysaccharide K1
  • polysialic acid