Effect of carbohydrates on fructosyltransferase expression and distribution in Streptococcus mutans GS-5 biofilms.
Streptococcus mutans produces a fructosyltransferase (FTF) enzyme, which synthesizes fructan polymers from sucrose. Fructans contribute to the virulence of the biofilm by acting as binding sites for S. mutans adhesion and as extracellular nutrition reservoir for the oral bacteria. Antibodies raised against a recombinant S. mutans FTF were used to test the effect of glucose, fructose, and sucrose on FTF expression in S. mutans GS-5 biofilms. Biofilms formed in the presence of fructose and glucose showed a higher ratio of FTF compared to biofilms formed in the presence of sucrose. Confocal laser scanning microscopy images of S. mutans biofilms indicated a carbohydrate-dependent FTF distribution. The layer adjacent to the surface and those at the liquid interface displayed high amounts cell-free FTF with limited amount of bacteria while the in-between layers demonstrated both cell-free FTF and cells expressing cell-surface FTF. Biofilm of S. mutans grown on hydroxyapatite surfaces expressed several FTF bands with molecular masses of 160, 125, 120, 100, and 50 kDa, as detected by using FTF specific antibodies. The results show that FTF expression and distribution in S. mutans GS-5 biofilms is carbohydrate regulated.
Rozen
Ramona
R
Institute of Dental Sciences, Faculty of Dentistry, Hebrew University-Hadassah, PO Box 12272, Jerusalem 91120, Israel.
Bachrach
Gilad
G
Steinberg
Doron
D
D000907:Antibodies, Bacterial; D018441:Biofilms; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics; D005632:Fructose / Q000494:pharmacology*; D015971:Gene Expression Regulation, Enzymologic; D005947:Glucose / Q000494:pharmacology*; D006602:Hexosyltransferases / Q000276:immunology / Q000378:metabolism*; D018613:Microscopy, Confocal; D008855:Microscopy, Electron, Scanning; D008970:Molecular Weight; D011994:Recombinant Proteins / Q000096:biosynthesis; D013295:Streptococcus mutans / Q000187:drug effects / Q000201:enzymology / Q000276:immunology; D013395:Sucrose / Q000494:pharmacology*; D001426:Bacterial Proteins
D000907:Antibodies, Bacterial; D005632:Fructose; D005947:Glucose; D006602:Hexosyltransferases; D011994:Recombinant Proteins; D013395:Sucrose; C021451:inulosucrase; D001426:Bacterial Proteins