Analysis of the Streptococcus downei gtfS gene, which specifies a glucosyltransferase that synthesizes soluble glucans.
AUTOR(ES)
Gilmore, K S
RESUMO
The complete nucleotide sequence was determined for the Streptococcus downei (previously Streptococcus sobrinus) MFe28 gtfS gene which specifies a glucosyltransferase (GTF-S) producing water-soluble glucan. A single open reading frame which encodes a mature protein with a molecular weight of 147,408 (1,328 amino acids) and a putative signal peptide 36 or 37 amino acids in length was detected. GTF-S shares extensive sequence similarity with GTF-I (gtfI) from S. downei and GTF-I (gtfB) and GTF-SI (gtfC) from Streptococcus mutans. GTF-S contains a highly conserved enzymatic domain and C-terminal repeated sequences which appear to be involved in glucan binding. Comparison of the deduced GTF-S protein sequence with other sequenced GTF genes of mutans streptococci revealed that these C-terminal repeats occurred in all cases, although the patterns of repeated sequences varied with respect to each other and to the glucan-binding protein of S. mutans. GTF-S contains four C-terminal repeat sequences ranging from 49 to 51 amino acids in length and a partial repeat of 13 amino acids. Nuclear magnetic resonance analysis of the glucan produced by GTF-S revealed that the product consisted of more than 90% alpha-1,6-linked glucosyl residues.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=258840Documentos Relacionados
- Isolation and characterization of the Streptococcus mutans gtfC gene, coding for synthesis of both soluble and insoluble glucans.
- Expression of gtfS is essential for normal insoluble glucan synthesis by Streptococcus downei.
- Cloning of a Streptococcus sobrinus gtf gene that encodes a glucosyltransferase which produces a high-molecular-weight water-soluble glucan.
- Isolation of an Active Catalytic Core of Streptococcus downei MFe28 GTF-I Glucosyltransferase
- Sequence analysis of the glucosyltransferase A gene (gtfA) from Streptococcus mutans Ingbritt.