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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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Characterization of the gene encoding hydroxylamine oxidoreductase in Nitrosomonas europaea.

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

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Transcription of all amoC copies is associated with recovery of Nitrosomonas europaea from ammonia starvation.

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