title: Nucleotide sequencing and transcriptional analysis of two tandem genes encoding glucosyltransferase (water-soluble-glucan synthetase) in Streptococcus cricetus HS-6.
abstract: Two tandem genes encoding glucosyltransferase synthesizing water-soluble glucan (GTF-S) were cloned from the lambda gene library of Streptococcus cricetus HS-6 (serotype a) using anti-GTF-S antibody, and the nucleotide sequences were analyzed. The two genes (ORF1 and ORF2) were identified as streptococcal glucosyltransferases based on the following evidence: [1] the deduced amino acid sequences of their products have an active site for catalytic action and C-terminal repeated units for dextran binding, and [2] a homology search revealed that the ORF1 and ORF2 products are homologous to the GtfS protein (77.4%) of S. downei Mfe28 and GtfT protein (83.8%) of S. sobrinus OMZ176, respectively, which are both known to have GTF-S activity. Therefore, ORF1 and ORF2 might be designated gtfS and gtfT of S. cricetus, respectively. A Northern blotting and RNase protection assay suggested that the gtfS and gtfT of S. cricetus are transcribed as a single bicistronic mRNA as well as separate monocistronic mRNAs. Primer extension analysis indicated multiple transcriptional start points for each gene.
authors.affiliation: Department of Microbiology, Okayama University Dental School, Okayama, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Inoue
authors.forename: T
authors.initials: T
authors.lastname: Inoue
authors.forename: A
authors.initials: A
authors.lastname: Miyagi
authors.forename: I
authors.initials: I
authors.lastname: Tanimoto
authors.forename: R
authors.initials: R
authors.lastname: Shingaki
authors.forename: H
authors.initials: H
authors.lastname: Ohta
authors.forename: K
authors.initials: K
authors.lastname: Fukui
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D003001:Cloning, Molecular; D005964:Glucosyltransferases / Q000737:chemistry / Q000235:genetics*; D008969:Molecular Sequence Data; D016366:Open Reading Frames; D013291:Streptococcus / Q000201:enzymology*; D014158:Transcription, Genetic
chemical_list: D005964:Glucosyltransferases