Role of galE on biofilm formation by Thermus spp.
Thermus thermophilus and Thermus aquaticus are thermophilic bacteria that are frequently found to attach to solid surfaces in hot springs to form biofilms. Uridine diphosphate (UDP)-galactose-4'-epimerase (GalE) is an enzyme that catalyzes the conversion of UDP-galactose to UDP-glucose, an important biochemical step in exopolysaccharide synthesis. We expressed GalE obtained from T. thermophilus HB8 in Escherichia coli and found that the enzyme is stable at 80 degrees C and can epimerize UDP-galactose to UDP-glucose and UDP-N-acetylgalactosamine (UDP-GalNAc) to UDP-N-acetylglucosamine (UDP-GlcNAc). Enzyme overexpression in T. thermophilus HB27 led to an increased capacity of biofilm production. Therefore, the galE gene is important to biofilm formation because of its involvement in epimerizing UDP-galactose and UDP-N-acetylgalactosamine for exopolysaccharide biosynthesis.
Institute of Microbiology, Immunology and Molecular Medicine, Tzu Chi University, Hualien 97002, Taiwan.
Yi-Kai
YK
Niou
Wan-Ling
WL
Wu
Ling-Chun
LC
Lin
Mei-Shiuan
MS
Yu
Hung-Yu
HY
Shu
Hsueh-Hui
HH
Yang
Guang-Huey
GH
Lin
D000595:Amino Acid Sequence; D018441:Biofilms / Q000254:growth & development*; D008969:Molecular Sequence Data; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D016963:Thermus thermophilus / Q000201:enzymology* / Q000502:physiology; D014534:UDPglucose 4-Epimerase / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*
D011994:Recombinant Proteins; D014534:UDPglucose 4-Epimerase; C020551:galactose epimerase