Cloning of the excC and excD Genes Involved in the Release of Periplasmic Proteins by Escherichia Coli K12

Mol Gen Genet. 1989 Sep;218(3):460-4. doi: 10.1007/BF00332410.


Strains of Escherichia coli K12 carrying a tolA, tolB, lky or exc mutation located at min 16.5 on the genetic map released periplasmic proteins into the extracellular medium. Wild-type genes defined by these mutations have been cloned from E. coli genomic bank made with plasmid pBR328. Subcloning experiments and complementation studies showed that lky and exc mutations were located either in the previously described tolA and tolB genes or in the newly characterized excC and excD genes. Using minicells, excC and excD gene products were identified as proteins with a molecular mass of 19 and 21 kDa, respectively.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alkaline Phosphatase / genetics
  • Bacterial Outer Membrane Proteins / genetics*
  • Cloning, Molecular
  • Electrophoresis, Polyacrylamide Gel
  • Escherichia coli / genetics*
  • Plasmids
  • Polymorphism, Restriction Fragment Length
  • Restriction Mapping
  • beta-Lactamases / genetics


  • Bacterial Outer Membrane Proteins
  • Alkaline Phosphatase
  • beta-Lactamases