RRC ID 15469
Author Miyamoto Y, Masaki T, Chohnan S.
Title Characterization of N-deoxyribosyltransferase from Lactococcus lactis subsp. lactis.
Journal Biochim. Biophys. Acta
Abstract A nucleoside N-deoxyribosyltransferase-homologous gene was detected by homological search in the genomic DNA of Lactococcus lactis subsp. lactis. The gene yejD is composed of 477 nucleotides encoding 159 amino acids with only 25% identity, which is low in comparison to the amino acid sequences of the N-deoxyribosyltransferases from other lactic acid bacteria, i.e. Lactobacillus leichmannii and Lactobacillus helveticus. The residues responsible for catalytic and substrate-binding sites in known enzymes are conserved at Gln49, Asp73, Asp93 (or Asp95), and Glu101, respectively. The recombinant YejD expressed in Escherichia coli shows a 2-deoxyribosyl transfer activity to and from both bases of purine and pyrimidine, showing that YejD should be categorized as a class II N-deoxyribosyltransferase. Interestingly, the base-exchange activity as well as the heat stability of YejD was enhanced by the presence of monovalent cations such as K(+), NH(4)(+), and Rb(+), indicating that the Lactococcus enzyme is a K(+)-activated Type II enzyme. However, divalent cations including Mg(2+) and Ca(2+) significantly inhibit the activity. Whether or not the yejD gene product actually participates in the nucleoside salvage pathway of Lc. lactis remains unclear, but the lactic acid bacterium possesses the gene coding for the nucleoside N-deoxyribosyltransferase activated by K(+) on its genome.
Volume 1774(10)
Pages 1323-30
Published 2007-10
DOI 10.1016/j.bbapap.2007.08.008
PII S1570-9639(07)00193-8
PMID 17881307
MeSH Amino Acid Sequence Cations, Monovalent / chemistry Escherichia coli / enzymology Escherichia coli / genetics Lactococcus lactis / enzymology* Lactococcus lactis / genetics Molecular Sequence Data Pentosyltransferases / biosynthesis Pentosyltransferases / chemistry* Pentosyltransferases / classification* Pentosyltransferases / genetics Potassium / physiology Recombinant Proteins / biosynthesis Recombinant Proteins / chemistry Recombinant Proteins / classification Recombinant Proteins / genetics
IF 3.438
Times Cited 8
General Microbes JCM 5805