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Transcript analysis of multiple copies of amo (encoding ammonia monooxygenase) and hao (encoding hydroxylamine oxidoreductase) in Nitrosomonas europaea.

ABSTRACT: The genes encoding ammonia monooxygenase (amoCAB), hydroxylamine oxidoreductase (hao), and the c-type cytochrome c-554 (hcy) are present in multiple copies in the genome of Nitrosomonas europaea. The upstream regions of the two copies of amoC, the three copies of hao, and one copy of hcy were cloned and sequenced. Primer extension reactions were done to identify transcription start sites for these genes, as well as for amoA. Putative sigma(70) promoter sequences were found associated with all but one of the mapped transcription start sites. Primer extensions were done with amoC primers using RNA harvested from cells incubated with and without ammonium. The experiments suggested that N. europaea cells may be able to use different promoters in the presence and absence of ammonium.

SUBMITTER: Hommes NG

PROVIDER: S-EPMC94979 | biostudies-literature | 2001 Feb

REPOSITORIES: biostudies-literature

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Transcript analysis of multiple copies of amo (encoding ammonia monooxygenase) and hao (encoding hydroxylamine oxidoreductase) in Nitrosomonas europaea.

Hommes N G NG Sayavedra-Soto L A LA Arp D J DJ

Journal of bacteriology 20010201 3

The genes encoding ammonia monooxygenase (amoCAB), hydroxylamine oxidoreductase (hao), and the c-type cytochrome c-554 (hcy) are present in multiple copies in the genome of Nitrosomonas europaea. The upstream regions of the two copies of amoC, the three copies of hao, and one copy of hcy were cloned and sequenced. Primer extension reactions were done to identify transcription start sites for these genes, as well as for amoA. Putative sigma(70) promoter sequences were found associated with all bu ...[more]

PMID: 11208810

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Mutagenesis and expression of amo, which codes for ammonia monooxygenase in Nitrosomonas europaea.

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Activity-Based Protein Profiling of Ammonia Monooxygenase in Nitrosomonas europaea.

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Organization of the hao gene cluster of Nitrosomonas europaea: genes for two tetraheme c cytochromes.

Project description:The organization of genes for three proteins involved in ammonia oxidation in Nitrosomonas europaea has been investigated. The amino acid sequence of the N-terminal region and four heme-containing peptides produced by proteolysis of the tetraheme cytochrome c554 of N. europaea were determined by Edman degradation. The gene (cycA) encoding this cytochrome is present in three copies per genome (H. McTavish, F. LaQuier, D. Arciero, M. Logan, G. Mundfrom, J.A. Fuchs, and A. B. Hooper, J. Bacteriol. 175:2445-2447, 1993). Three clones, representing at least two copies of cycA, were isolated and sequenced by the dideoxy-chain termination procedure. In both copies, the sequences of 211 amino acids derived from the gene sequence are identical and include all amino acids predicted by the proteolytic peptides. In two copies, the cycA open reading frame (ORF) is followed closely (three bases in one copy) by a second ORF predicted to encode a 28-kDa tetraheme c cytochrome not previously characterized but similar to the nirT gene product of Pseudomonas stutzeri. In one copy of the cycA gene cluster, the second ORF is absent.

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