[Screening of food-grade microorganisms for biotransformation of D-tagatose and cloning and expression of L-arabinose isomerase].
L-Arabinose isomerase (L-AI) is an intracellular enzyme that catalyzes the reversible isomerization of D-galactose and D-tagatose. Given the widespread use of D-tagatose in the food industry, food-grade microorganisms and the derivation of L-AI for the production of D-tagatose is gaining increased attention. In the current study, food-grade strains from different foods that can convert D-galactose to D-tagatose were screened. According to physiological, biochemical, and 16S rDNA gene analyses, the selected strain was found to share 99% identity with Pediococcus pentosaceus, and was named as Pediococcus pentosaceus PC-5. The araA gene encoding L-AI from Pediococcus pentosaceus PC-5 was cloned and overexpressed in E. coli BL21. The yield of D-tagatose using D-galactose as the substrate catalyzed by the crude enzyme in the presence of Mn2+ was found to be 33% at 40 degrees C.
College of Biology Engineering, Tianjin University of Science and Technology, Tianjin 300457, China.
Yan
Y
Men
Yueming
Y
Zhu
Yuping
Y
Guan
Tongcun
T
Zhang
Ken
K
Izumori
Yuanxia
Y
Sun
D019747:Aldose-Ketose Isomerases / Q000096:biosynthesis* / Q000235:genetics*; D001711:Biotransformation; D003001:Cloning, Molecular; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D005690:Galactose / Q000378:metabolism; D005822:Genetic Vectors / Q000235:genetics; D006601:Hexoses / Q000378:metabolism*; D010376:Pediococcus / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification; D011994:Recombinant Proteins / Q000096:biosynthesis* / Q000235:genetics
D006601:Hexoses; D011994:Recombinant Proteins; D019747:Aldose-Ketose Isomerases; C019715:L-arabinose isomerase; C030192:tagatose; D005690:Galactose