PMCCPMCCPMCC

Search tips
Search criteria 

Advanced

 
Logo of jbacterPermissionsJournals.ASM.orgJournalJB ArticleJournal InfoAuthorsReviewers
 
J Bacteriol. Feb 1991; 173(3): 989–996.
PMCID: PMC207216
Peptide sequences for sucrose splitting and glucan binding within Streptococcus sobrinus glucosyltransferase (water-insoluble glucan synthetase).
H Abo, T Matsumura, T Kodama, H Ohta, K Fukui, K Kato, and H Kagawa
Department of Oral and Maxillo-Facial Surgery II, Okayama University Dental School, Japan.
Abstract
The gene encoding glucosyltransferase responsible for water-insoluble glucan synthesis (GTF-I) of Streptococcus sobrinus (formerly Streptococcus mutans 6715) was cloned, expressed, and sequenced. A gene bank from S. sobrinus 6715 DNA was constructed in vector pUC18 and screened with anti-GTF-I antibody to detect clones producing GTF-I peptide. Five immunopositive clones were isolated, all of which produced peptides that bound alpha-1,6 glucan. GTF-I activity was found in only two large peptides: one stretching over the full length of the GTF-I peptide and composed of about 1,600 amino acid residues (AB1 clone) and the other lacking about 80 N-terminal residues and about 260 C-terminal residues (AB2 clone). A deletion study of the AB2 clone indicated that specific glucan binding, which is essential for water-insoluble glucan synthesis, was lost prior to sucrase activity with an increase in deletion from the 3' end of the GTF-I gene. These results suggest that the GTF-I peptide consists of three segments: that for sucrose splitting (approximately 1,100 residues), that for glucan binding (approximately 240 residues), and that of unknown function (approximately 260 residues), in order from the N terminus. The primary structure of the GTF-I peptide, deduced by DNA sequencing of the AB1 clone, was found to be very similar to that of the homologous protein from another strain of S. sobrinus.
Full text
Full text is available as a scanned copy of the original print version. Get a printable copy (PDF file) of the complete article (1.7M), or click on a page image below to browse page by page.
Images in this article
Click on the image to see a larger version.
Articles from Journal of Bacteriology are provided here courtesy of
American Society for Microbiology (ASM)