[Influence of luxS of Streptococcus mutans on biofilm of dental plaque].
OBJECTIVE
To construct luxS mutant aften luxS gene of Streptococcus mutans (S. mutans) was knocked out, and examine their ability of biofilm formation.


METHODS
A recombinant plasmid containing the flanking fragment of luxS of S. mutans was transformed into S. mutans UA159, and selected by brain heart infusion (BHI) agar medium with kanamicin. The luxS mutant further confirmed via polymerase chain reaction (PCR) and the autoinducer-2 (AI-2) bioluminescence assay of Vibrio harveyi (V. harveyi), and ability of luxS mutant and S. mutans UA159 biofilm formation was examined in different phases, in BHI medium with 1% sucrose and 1% glycose by scanning electron microscopy (SEM).


RESULTS
LuxS-deficient S. mutans strains were successfully constructed. Compared with S. mutans UA159, the luxS mutant maintained in BHI medium containing 1% sucrose displayed an apparent defect in biofilm formation, while they showed no significant deviation in BHI medium containing 1% glycose.


CONCLUSIONS
luxS gene in S.mutans can play a role in dental plaque biofilm formation, and the luxS gene is possible to regulate sucrose-dependent biofilm formation.
Tong
Zhong-chun
ZC
Dept. of Conservative Dentistry, School of Stomatology, The Fourth Military Medical University, Xi'an 710032, China.
Ni
Long-xing
LX
Ma
Li-fang
LF
Zhou
Lin
L
Hou
Bo
B
Zhao
Xiu
X
D001426:Bacterial Proteins; D018441:Biofilms; D013437:Carbon-Sulfur Lyases; D003470:Culture Media; D003773:Dental Plaque; D006714:Homoserine / Q000031:analogs & derivatives; D006801:Humans; D007783:Lactones; D013295:Streptococcus mutans
D001426:Bacterial Proteins; D003470:Culture Media; D007783:Lactones; C091088:N-octanoylhomoserine lactone; D006714:Homoserine; D013437:Carbon-Sulfur Lyases