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Title: The NADH-binding subunit of the energy-transducing NADH-ubiquinone oxidoreductase of Paracoccus denitrificans: Gene cloning and deduced primary structure

Journal Article · · Biochemistry; (United States)
DOI:https://doi.org/10.1021/bi00240a012· OSTI ID:5032398
; ;  [1]
  1. Research Inst. of Scripps Clinic, La Jolla, CA (United States)

The NADH dehydrogenase complex isolated from Paracoccus denitrificans is composed of approximately 10 unlike polypeptides and contains noncovalently bound FMN, non-heme iron, and acid-labile sulfide. The NADH-binding subunit of this enzyme complex was identified by direct photoaffinity labeling with ({sup 32}P)NADH. primers were synthesized on the basis of the N-terminal amino acid sequency of this polypeptide, and these primers were used to synthesize an oligonucleotide probe by the polymerase chain reaction. This probe was utilized to isolate the gene encoding the NADH-binding subunit from a genomic library of P. denitrificans. The nucleotide sequence of the gene and the deduced amino acid sequence of the entire NADH-binding subunit were determined. The NADH-binding subunit has 431 amino acid residues and a calculated molecular weight of 47 191. The encoded protein contains a putative NAD(H)-binding and an iron-sulfur cluster-binding consensus sequence. The deduced amino acid sequence of the Paracoccus NADH-binding subunit shows remarkable similarity to the {alpha} subunit of the NAD-linked hydrogenase of Alcaligenes eutrophus H16. When partial DNA sequencing of the regions surrounding the gene encoding the NADH-binding subunit was carried out, sequences homologous to the 24-, 49-, and 75-kDa polypeptides of bovine complex 1 were detected, suggesting that the structural genes of the Paracoccus NADH dehydrogenase complex constitute a gene cluster.

OSTI ID:
5032398
Journal Information:
Biochemistry; (United States), Vol. 30:26; ISSN 0006-2960
Country of Publication:
United States
Language:
English