Genetic locus (ompB) affecting a major outer-membrane protein in Escherichia coli K-12.

Three multiply colicin-tolerant mutants in Escherichia coli K-12 from the TolIV, TolXIV, and TolXV phenotypic groups, all lacking or having only trace amounts of protein 1, a major outer-membrane protein, were mapped by Hfr crosses, and the position on the chromosome was confirmed by cotransduction with nearby markers. The mutations were located near malQP in the 74-min region of the E. coli chromosome. This locus is designated ompB, and analysis of data from two three-point crosses determined the linear sequence of genes to be aroB-ompB-malQP-glpD.