Dataset Information

CumA, a gene encoding a multicopper oxidase, is involved in Mn2+ oxidation in Pseudomonas putida GB-1.

ABSTRACT: Pseudomonas putida GB-1-002 catalyzes the oxidation of Mn2+. Nucleotide sequence analysis of the transposon insertion site of a nonoxidizing mutant revealed a gene (designated cumA) encoding a protein homologous to multicopper oxidases. Addition of Cu2+ increased the Mn2+-oxidizing activity of the P. putida wild type by a factor of approximately 5. The growth rates of the wild type and the mutant were not affected by added Cu2+. A second open reading frame (designated cumB) is located downstream from cumA. Both cumA and cumB probably are part of a single operon. The translation product of cumB was homologous (level of identity, 45%) to that of orf74 of Bradyrhizobium japonicum. A mutation in orf74 resulted in an extended lag phase and lower cell densities. Similar growth-related observations were made for the cumA mutant, suggesting that the cumA mutation may have a polar effect on cumB. This was confirmed by site-specific gene replacement in cumB. The cumB mutation did not affect the Mn2+-oxidizing ability of the organism but resulted in decreased growth. In summary, our data indicate that the multicopper oxidase CumA is involved in the oxidation of Mn2+ and that CumB is required for optimal growth of P. putida GB-1-002.

SUBMITTER: Brouwers GJ

PROVIDER: S-EPMC91248 | biostudies-literature | 1999 Apr

REPOSITORIES: biostudies-literature

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cumA, a gene encoding a multicopper oxidase, is involved in Mn2+ oxidation in Pseudomonas putida GB-1.

Brouwers G J GJ de Vrind J P JP Corstjens P L PL Cornelis P P Baysse C C de Vrind-de Jong E W EW

Applied and environmental microbiology 19990401 4

Pseudomonas putida GB-1-002 catalyzes the oxidation of Mn2+. Nucleotide sequence analysis of the transposon insertion site of a nonoxidizing mutant revealed a gene (designated cumA) encoding a protein homologous to multicopper oxidases. Addition of Cu2+ increased the Mn2+-oxidizing activity of the P. putida wild type by a factor of approximately 5. The growth rates of the wild type and the mutant were not affected by added Cu2+. A second open reading frame (designated cumB) is located downstream ...[more]

PMID: 10103278

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Dataset Information

CumA, a gene encoding a multicopper oxidase, is involved in Mn2+ oxidation in Pseudomonas putida GB-1.

Publications

cumA, a gene encoding a multicopper oxidase, is involved in Mn2+ oxidation in Pseudomonas putida GB-1.

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