A critical role of an oxygen-responsive gene for aerobic nitrogenase activity in Azotobacter vinelandii and its application to Escherichia coli.

ABSTRACT: Since nitrogenase is irreversibly inactivated within a few minutes after exposure to oxygen, current studies on the heterologous expression of nitrogenase are limited to anaerobic conditions. This study comprehensively identified genes showing oxygen-concentration-dependent expression only under nitrogen-fixing conditions in Azotobacter vinelandii, an aerobic diazotroph. Among the identified genes, nafU, with an unknown function, was greatly upregulated under aerobic nitrogen-fixing conditions. Through replacement and overexpressing experiments, we suggested that nafU is involved in the maintenance of nitrogenase activity under aerobic nitrogenase activity. Furthermore, heterologous expression of nafU in nitrogenase-producing Escherichia coli increased nitrogenase activity under aerobic co

SUBMITTER: Takimoto R 

PROVIDER: S-EPMC8907163 | biostudies-literature | 2022 Mar

REPOSITORIES: biostudies-literature