Azotobacter vinelandii aldehyde dehydrogenase regulated by sigma(54): role in alcohol catabolism and encystment.
Encystment in Azotobacter vinelandii is induced by n-butanol or beta-hydroxybutyrate (BHB). We identified a gene, encoding an aldehyde dehydrogenase, that was named aldA. An aldA mutation impaired bacterial growth on n-butanol, ethanol, or hexanol as the sole carbon source. Expression of aldA increased in cells shifted from sucrose to n-butanol and was shown to be dependent on the alternative sigma(54) factor. A mutation in rpoN encoding the sigma(54) factor also impaired growth on alcohols. Encystment on n-butanol, but not on BHB, was impaired in aldA or rpoN mutants, indicating that n-butanol is not an inducer of encystment by itself but must be catabolized in order to induce encystment.
Gama-Castro
S
S
Departamento de Microbiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, Morelos 62250, Mexico.
Núñez
C
C
Segura
D
D
Moreno
S
S
Guzmán
J
J
Espín
G
G
D020001:1-Butanol / Q000494:pharmacology; D000438:Alcohols / Q000378:metabolism*; D000444:Aldehyde Dehydrogenase / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D000445:Aldehyde Oxidoreductases / Q000235:genetics / Q000378:metabolism* / Q000502:physiology*; D016948:Azotobacter vinelandii / Q000201:enzymology* / Q000254:growth & development*; D001426:Bacterial Proteins; D001483:Base Sequence; D003001:Cloning, Molecular; D004268:DNA-Binding Proteins; D012321:DNA-Directed RNA Polymerases / Q000235:genetics / Q000502:physiology*; D005816:Genetic Complementation Test; D008969:Molecular Sequence Data; D009154:Mutation; D011401:Promoter Regions, Genetic; D051877:RNA Polymerase Sigma 54; D012808:Sigma Factor / Q000235:genetics / Q000502:physiology*
D000438:Alcohols; D001426:Bacterial Proteins; D004268:DNA-Binding Proteins; D012808:Sigma Factor; D020001:1-Butanol; C439049:AldA protein, Azotobacter vinelandii; D000445:Aldehyde Oxidoreductases; D000444:Aldehyde Dehydrogenase; D012321:DNA-Directed RNA Polymerases; D051877:RNA Polymerase Sigma 54