Mutants of Escherichia coli defective in membrane phospholipid synthesis: Mapping of the structural gene for L glycerol 3 phosphate dehydrogenase

The structural gene for the biosynthetic L glycerol 3 phosphate dehydrogenase was mapped at min 7.15 on the Escherichia coli chromosome. This gene (gpsA) is co transduced with the xyl, mtl, and pyrE loci. Three factor conjugational crosses and the transduction data indicate that the order of loci in this region of the chromosome is mtl, gltE, gpsA, gadR, gadS, pyrE. Study of a temperature sensitive gpsA mutant possessing a dehydrogenase of increased thermolability indicated that gpsA is the structural gene for the dehydrogenase. All dehydrogenase deficient strains tested were mapped very close to the gpsA locus. Attempts at genetic complementation analysis were unsuccessful.