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NdhP and NdhQ: two novel small subunits of the cyanobacterial NDH-1 complex.

ABSTRACT: The subunit composition of the NAD(P)H dehydrogenase complex of Thermosynechococcus elongatus was analyzed by different types of mass spectrometry. All 15 known subunits (NdhA-NdhO) were identified in the purified NDH-1L complex. Moreover, two additional intact mass tags of 4902.7 and 4710.5 Da could be assigned after reannotation of the T. elongatus genome. NdhP and NdhQ are predicted to contain a single transmembrane helix each, and homologues are apparent in other cyanobacteria. Additionally, ndhP is present in some cyanophages in a cluster of PSI genes and exhibits partial similarity to NDF6, a subunit of the plant NDH-1 complex.

SUBMITTER: Nowaczyk MM

PROVIDER: S-EPMC3040284 | biostudies-literature | 2011 Feb

REPOSITORIES: biostudies-literature

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NdhP and NdhQ: two novel small subunits of the cyanobacterial NDH-1 complex.

Nowaczyk Marc M MM Wulfhorst Hannes H Ryan Christopher M CM Souda Puneet P Zhang Huamin H Cramer William A WA Whitelegge Julian P JP

Biochemistry 20110127 7

The subunit composition of the NAD(P)H dehydrogenase complex of Thermosynechococcus elongatus was analyzed by different types of mass spectrometry. All 15 known subunits (NdhA-NdhO) were identified in the purified NDH-1L complex. Moreover, two additional intact mass tags of 4902.7 and 4710.5 Da could be assigned after reannotation of the T. elongatus genome. NdhP and NdhQ are predicted to contain a single transmembrane helix each, and homologues are apparent in other cyanobacteria. Additionally, ...[more]

PMID: 21244052

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