Suppressor of phosphofructokinase mutations of Escherichia coli

The known locus of fructose-6-phosphate kinase mutations (pfkA) in Escherichia coli is at 76 min on the genetic map. We have now found another gene, pfkB, at 33 min, mutation of which suppresses pfkA mutations. The suppression is not informational, and pfkB may be a second gene for fructose-6-phosphate kinase activity.