Cloning and sequence analysis of the gbpC gene encoding a novel glucan-binding protein of Streptococcus mutans.
We have isolated dextran-aggregation-negative mutants of Streptococcus mutans following random mutagenesis with plasmid pVA891 clone banks. A chromosomal region responsible for this phenotype was characterized in one of the mutants. A 2.2-kb fragment from the region was cloned in Escherichia coli and sequenced. A gene specifying a putative protein of 583 amino acid residues with a calculated molecular weight of 63,478 was identified. The amino acid sequence deduced from the gene exhibited no similarity to the previously identified S. mutans 74-kDa glucan-binding protein or to glucan-binding domains of glucosyltransferases but exhibited similarity to surface protein antigen (Spa)-family proteins from streptococci. Extract from an E. coli clone of the gene exhibited glucan-binding activity. Therefore, the gene encoded a novel glucan-binding protein.
Sato
Y
Y
Department of Biochemistry, Tokyo Dental College, Chiba City, Japan.
Yamamoto
Y
Y
Kizaki
H
H
D000595:Amino Acid Sequence; D001422:Bacterial Adhesion / Q000187:drug effects; D001483:Base Sequence; D015153:Blotting, Western; D002352:Carrier Proteins / Q000737:chemistry / Q000235:genetics*; D003001:Cloning, Molecular; D003911:Dextrans / Q000494:pharmacology; D004926:Escherichia coli / Q000235:genetics; D015964:Gene Expression Regulation, Bacterial; D005798:Genes, Bacterial; D005936:Glucans / Q000378:metabolism*; D037102:Lectins; D008969:Molecular Sequence Data; D016296:Mutagenesis; D010957:Plasmids; D017421:Sequence Analysis; D013295:Streptococcus mutans / Q000737:chemistry / Q000235:genetics* / Q000302:isolation & purification
D002352:Carrier Proteins; D003911:Dextrans; D005936:Glucans; D037102:Lectins; C037937:glucan-binding proteins