Molecular cloning and sequence analysis of the gene encoding the H2O2-forming NADH oxidase from Streptococcus mutans.
Streptococcus mutans induces both H2O2-forming and H2O-forming NADH oxidases in the presence of O2 [M. Higuchi, J. Gen. Microbiol., 130, 1819-1826 (1984)]. In this paper, a nox-1 gene encoding H2O2-forming NADH oxidase (NOX-1) from Streptococcus mutans was cloned, and the nucleotides sequenced. The structural gene of nox-1 consisted of 1530 base pairs, which encode a polypeptide consisting of 510 amino acids with a predicted molecular mass of 55,196 Da. The deduced N-terminal amino acid sequence was consistent with that previously found for the purified NOX-1 protein. The nox-1 gene was expressed in Escherichia coli using its own promoter. Alignment of the amino acid sequence of NOX-1 with those of NADH oxidases from other microorganisms showed identities of 55.6%, 20.8%, 20.3%, and 7.3% for those of Amphibacillus xylanus Ep01, Streptococcus faecalis 10C1, Thermoanaerobium brockii Rt8.G4, and Thermus thermophilus HB8, respectively.
Higuchi
M
M
Research Center, Nippon Paint Co., Ltd., Osaka, Japan.
Shimada
M
M
Matsumoto
J
J
Yamamoto
Y
Y
Rhaman
A
A
Kamio
Y
Y
D000595:Amino Acid Sequence; D001421:Bacteria, Anaerobic / Q000201:enzymology / Q000235:genetics; D001426:Bacterial Proteins / Q000235:genetics*; D001483:Base Sequence; D003001:Cloning, Molecular; D013293:Enterococcus faecalis / Q000201:enzymology / Q000235:genetics; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics; D015870:Gene Expression; D008969:Molecular Sequence Data; D009097:Multienzyme Complexes / Q000235:genetics*; D009247:NADH, NADPH Oxidoreductases / Q000235:genetics*; D019255:NADPH Oxidases; D017386:Sequence Homology, Amino Acid; D013295:Streptococcus mutans / Q000235:genetics* / Q000378:metabolism*; D016963:Thermus thermophilus / Q000235:genetics / Q000378:metabolism
D001426:Bacterial Proteins; D009097:Multienzyme Complexes; C023107:NADH oxidase; D009247:NADH, NADPH Oxidoreductases; D019255:NADPH Oxidases; C022709:superoxide-forming enzyme