TITLE:
LicT Modulates Biofilm Formation of Streptococcus pyogenes
AUTHORS:
Masaaki Minami, Hiroshi Takase, Ryoko Sakakibara, Taichi Imura, Hideo Morita, Michio Ohta
KEYWORDS:
Streptococcus pyogenes, LicT, Biofilm
JOURNAL NAME:
Journal of Biosciences and Medicines,
Vol.2 No.9,
November
25,
2014
ABSTRACT: Streptococcus pyogenes frequently causes
purulent infections in humans. Biofilm formation is an important virulence
property of S. pyogenes because of decreased susceptibility of bacteria to antibiotic
treatment. Biofilm is composed of various types of matrix including glycocalyx
which is an important exocellular matrix material related to bacterial sugar
metabolism. A putative antiterminator protein, LicT (Spy0571), is one of the
components of the glucose-independent β-gluco-side-specific phosphotransferase
system (PTS). Although the PTS, a carbohydrate metabolic system, may play a
role in biofilm formation, the relationship between LicT and biofilm formation
has not yet been elucidated. Here, we evaluated whether LicT affected biofilm
formation in modified chemically defined medium (CDMM) supplemented with
glucose or β-glucoside:salicin. We created licT- and licT-complemented mutant
strains from S. pyogenes 1529. Although the licT mutant strain tended to have
higher growth rate than wild-typestrain in CDMM with glucose, it had a significant
lower growth rate than the wild-type strain in CDMM with salicin. In addition,
the licT mutant exhibited lower biofilm formation in CDMM containing salicin
than the wild-type strain by 96 well plate analysis and confocal laser scanning
microscopic analysis. Our results suggest that LicT plays an important role in
biofilm formation of S. pyogenes.