title: Sugar Allocation to Metabolic Pathways is Tightly Regulated and Affects the Virulence of Streptococcus mutans.
abstract: Bacteria take up and metabolize sugar as a carbohydrate source for survival. Most bacteria can utilize many sugars, including glucose, sucrose, and galactose, as well as amino sugars, such as glucosamine andN-acetylglucosamine. After entering the cytoplasm, the sugars are mainly allocated to the glycolysis pathway (energy production) and to various bacterial component biosynthesis pathways, including the cell wall, nucleic acids and amino acids. Sugars are also utilized to produce several virulence factors, such as capsule and lipoteichoic acid. Glutamine-fructose-6-phosphate aminotransferase (GlmS) and glucosamine-6-phosphate deaminase (NagB) have crucial roles in sugar distribution to the glycolysis pathway and to cell wall biosynthesis. InStreptococcus mutans, a cariogenic pathogen, the expression levels ofglmSandnagBare coordinately regulated in response to the presence or absence of amino sugars. In addition, the disruption of this regulation affects the virulence ofS. mutans. The expression ofnagBandglmSis regulated by NagR inS. mutans, but the precise mechanism underlyingglmSregulation is not clear. InStaphylococcus aureusandBacillus subtilis, the mRNA ofglmShas ribozyme activity and undergoes self-degradation at the mRNA level. However, there is no ribozyme activity region onglmSmRNA inS. mutans. In this review article, we summarize the sugar distribution, particularly the coordinated regulation of GlmS and NagB expression, and its relationship with the virulence ofS. mutans.
authors.affiliation: Department of Oral Microbiology, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima 890-8544, Japan. mmatsuo@dent.kagoshima-u.ac.jp.
authors.forename: Miki
authors.initials: M
authors.lastname: Kawada-Matsuo
authors.affiliation: Department of Oral Microbiology, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima 890-8544, Japan. oogai@dent.kagoshima-u.ac.jp.
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Oogai
authors.affiliation: Department of Oral Microbiology, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima 890-8544, Japan. hkomatsu@dent.kagoshima-u.ac.jp.
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Komatsuzawa
keywords: GlmS; NagB; Streptococcus mutans; sugar distribution; virulence