Selection and characterization of aspartokinase feedback-insensitive mutants of Azotobacter vinelandii

Abstract

Aspartokinase feedback-insensitive mutants of Azotobacter vinelandii were selected as resistant to L-threonine, β-hydroxynorvaline, or S-(2- aminoethyl)-L-cysteine. L-Threonine-resistant strains were classified into three groups based on their ability to transport L-threonine and their growth response to O-methylthreonine and β-hydroxynorvaline. Most of the mutants were transport defective; however, some were desensitized to feedback regulation.