Abstract

Jeong-Min Jeon1 , Hae-In Lee1 and Jae-Seong So1,2*

We investigated the properties of glutaminase activity of Lactobacillus reuteri KCTC3594 and expressed the glutaminase gene (EC 3.5.1.2) heterologously. The enzyme activity was optimal at pH 7.5 and 40°C. High salt–tolerance of the enzyme was observed as 50% of the initial activity although it still remained at 20% (w/v) NaCl for 30 min. The glutaminase gene was cloned from L. reuteri KCTC3594 by PCR, and subsequently introduced into two Korean isolates of Lactobacillus species. All of the transformants harboring the glutaminase gene from L. reuteri KCTC3594 were able to elevate glutaminase activity when introduced into other lactobacilli.