Isolation and characterization of Escherichia coli mutants defective in enzymes of glycolysis

Abstract

A selection procedure has been developed that has yielded Escherichia coli mutants lacking the enzymes glyceraldehyde 3-P dehydrogenase (GAD), glycerate 3-P kinase (PGK) and enolase (ENO). The mutants fail to grow on sugar alone or on glycerol alone or on any oxidative substrate alone. They grow on synthetic media when glycerol and an oxidative substrate are present together; the addition of glucose, gluconate and many other sugars inhibits their growth. Reversion studies performed with these mutants suggest that the enzyme losses are due to single gene lesions. Preliminary mapping studies indicate the gene order as argG pgk lysA thyA eno gad tyrA.