α-Galactosidase를 생산하는 고온성 Bacillus coagulans KM-1 균주의 생화학적 특성

【A bacterium producing ${\alpha}$ -galactosidase ( ${\alpha}$ - $\small{D}$ -galactoside galactohydrolase, EC 3.2.1.22) was isolated. The isolate, KM-1 was identified as Bacillus coagulans based on its 16S rRNA sequence, morphology, and biochemical properties. ${\alpha}$ -Galactosidase activity was detected the culture supernatant of B. coagulans KM-1. The bacterium showed the maximum activity for hydrolyzing para-nitrophenyl- ${\alpha}$ - $\small{D}$ -galactopyranoside (pNP- ${\alpha}Gal$ ) at pH 6.0 and $50^{\circ}C$ . It hydrolyzed oligomeric substrates such as melibiose, raffinose, and stachyose liberating a galactose residue, indicating that the B. coagulans KM-1 ${\alpha}$ -galactosidase hydrolyzed ${\alpha}$ -1,6 linkage. The results suggest that the decreased stachyose and raffinose contents in fermented soybean meal are due to the ${\alpha}$ -galactosidase activity.】