Mutation affecting resistance of Escherichia coli K12 to nalidixic acid

Abstract

A new mutation, nalD, determining resistance of Escherichia coli to nalidixic acid (NAL) is reported. The nalD mutant described is resistant to NAL at 37°C but sensitive at 30°C. It is defective in penetration of NAL and glycerol through the outer membrane at 37°C. The nalD mutation is located half-way between 89 and 89.5 min on the E. coli genetic map.