title: 6-Hydroxy-D-nicotine oxidase of Arthrobacter oxidans. Gene structure of the flavoenzyme and its relationship to 6-hydroxy-L-nicotine oxidase.
abstract: The nucleotide sequence of the 6-hydroxy-D-nicotine oxidase (6-HDNO) gene of Arthrobacter oxidans is presented. This covalently flavinylated enzyme specifically oxidizes 6-hydroxy-D-nicotine to 6-hydroxy-N-methylmyosmine. Coinduced in the presence of nicotine is a 6-hydroxy-L-nicotine-specific enzyme, 6-hydroxy-L-nicotine oxidase (6-HLNO), with FAD noncovalently bound to the apoprotein. A comparison of the nucleotide-derived amino acid sequence of the 6-HDNO with the amino acid sequence data obtained from the purified 6-HLNO polypeptide suggests that the two enantiozymes expressed within the same cell are genetically unrelated. This conclusion is supported by the finding that the FAD-binding sites of the two enzymes are different. 6-HLNO exhibits at the amino-terminus of the polypeptide chain a dinucleotide-binding site characteristic for many other FAD- and NAD(P)-dependent enzymes. No such sequence was found in the nucleotide-derived amino acid sequence of 6-HDNO.
mesh_terms: D000595:Amino Acid Sequence; D001173:Arthrobacter / Q000201:enzymology*; D001483:Base Sequence; D004269:DNA, Bacterial / Q000032:analysis; D005182:Flavin-Adenine Dinucleotide / Q000378:metabolism; D010088:Oxidoreductases / Q000235:genetics*; D010449:Peptide Mapping; D012260:Ribonucleases / Q000378:metabolism; D014158:Transcription, Genetic
chemical_list: D004269:DNA, Bacterial; D005182:Flavin-Adenine Dinucleotide; D010088:Oxidoreductases; C021413:6-hydroxy-D-nicotine oxidase; D012260:Ribonucleases