Physical map of the nrdA-nrdB-ftsB-glpT region of the chromosomal DNA of Escherichia coli.

Seven pLC plasmids (pLC 3-46, 8-12, 8-24, 8-29, 14-12, 19-24 and 42-17) which complemented nrdA, nrdB, ftsB and/or glpT mutations of Escherichia coli were analyzed. A restriction map of each plasmid was constructed and restriction fragments were subcloned into pBR322. A physical map of approx. a 15 X 10(6) Mr segment of the chromosomal DNA was deduced from the overlapping region of the pLC plasmids. The pLC plasmids and newly constructed plasmids were examined for the ability to rescue the mutations. The complementation tests defined the location of the genes in the 15 X 10(6) Mr segment in the following order: nrdA-nrdB-ftsB-glpT. Functional nrdAB and ftsB genes were located in the 3.1 X 10(6) Mr EcoRI-PstI fragment.