Functional role of pyruvate kinase from Lactobacillus bulgaricus in acid tolerance and identification of its transcription factor by bacterial one-hybrid.

ABSTRACT: Lactobacillus delbrueckii subsp. bulgaricus develops acid tolerance response when subjected to acid stress conditions, such as the induction of enzymes associated with carbohydrate metabolism. In this study, pyk gene encoding pyruvate kinase was over-expressed in heterologous host Lactococcus lactis NZ9000, and SDS-PAGE analysis revealed the successful expression of this gene in NZ9000. The survival rate of Pyk-overproducing strain was 45-fold higher than the control under acid stress condition (pH 4.0). In order to determine the transcription factor (TF) which regulates the expression of pyk by bacterial one-hybrid, we constructed a TF library including 65 TFs of L. bulgaricus. Western blotting indicated that TFs in this library could be successfully expressed in host strains. Subsequentl

SUBMITTER: Zhai Z 

PROVIDER: S-EPMC4652205 | biostudies-literature | 2015 Nov

REPOSITORIES: biostudies-literature