cumA, a gene encoding a multicopper oxidase, is involved in Mn{sup 2+} oxidation in Pseudomonas putida GB-1

Journal Article · Thu Apr 01 04:00:00 EST 1999 · Applied and Environmental Microbiology

OSTI ID:343585

Brouwers, G J; Vrind, J P.M. de; Corstjens, P L.A.M.; Cornelis, P; Baysse, C ^[1]

---

1. Vrije Univ. Brussel (Belgium). Dept. of Immunology, Paracytology and Ultrastructure

Pseudomonas putida GB-1-002 catalyzes the oxidation of Mn{sup 2+}. 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 Cu{sup 2+} increased the Mn{sup 2+}-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 Cu{sup 2+}. 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 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 Mn{sup 2+}-oxidizing ability of the organism but resulted in decreased growth. In summary, the data indicate that the multicopper oxidase CumA is involved in the oxidation of Mn{sup 2+} and that CumB is required for optimal growth of P. putida GB-1-002.

• OSTI ID: 343585
• Journal Information: Applied and Environmental Microbiology, Journal Name: Applied and Environmental Microbiology Journal Issue: 4 Vol. 65; ISSN AEMIDF; ISSN 0099-2240
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
AMINO ACID SEQUENCE
BIODEGRADATION
COPPER
GENES
MANGANESE
OXIDOREDUCTASES
PSEUDOMONAS
REMEDIAL ACTION