title: Comparative mRNA Expression Profiles of Riboflavin Biosynthesis Genes in Lactobacilli Isolated from Human Feces and Fermented Bamboo Shoots.
abstract: With the aim to bioprospect potent riboflavin producing lactobacilli, the present study was carried out to evaluate the relative mRNA expression of riboflavin biosynthesis genes namelyRib1,Rib2,Rib3, andRib4 from potent riboflavin producers obtained from our previous studies. All the four genes were successfully cloned and sequenced for further analysis byin silicoprocedures. As studied by non-denaturing Polyacrylamide gel electrophoresis, no difference in size of all the four genes among those of various lactobacilli was observed. The relative fold increase in mRNA expression inRib1,Rib2,Rib3, andRib4 genes has been observed to be 10-, 1-, 0.7-, and 8.5-fold, respectively. Due to increase in relative mRNA expression for all theRibgenes as well as phenotypic production attribute, KTLF1 strain was used further for expression studies in milk and whey. The fold increase in mRNA expression for all the fourRibgenes was higher at 12 and 18 h in milk and whey respectively. After exposure to roseoflavin, resistant variant of KTLF1 showed considerable increase in expression of all the targets genes. This is the first ever study to compare the mRNA expression of riboflavin biosynthesis pathway genes in lactobacilli and it also under lines the effect of media and harvesting time which significantly affect the expression ofribgenes. The use of roseoflavin-resistant strains capable of synthesizing riboflavin in milk and whey paves a way for an exciting and economically viable biotechnological approach to develop novel riboflavin bio-enriched functional foods.
authors.affiliation: Dairy Microbiology Division, Indian Council of Agricultural Research - National Dairy Research InstituteKarnal, India; School of Food Science and Engineering, Hefei University of TechnologyHefei, China.
authors.forename: Kiran
authors.initials: K
authors.lastname: Thakur
authors.affiliation: Dairy Microbiology Division, Indian Council of Agricultural Research - National Dairy Research Institute Karnal, India.
authors.forename: Sudhir K
authors.initials: SK
authors.lastname: Tomar
authors.affiliation: School of Food Science and Engineering, Hefei University of Technology Hefei, China.
authors.forename: Zhao-Jun
authors.initials: ZJ
authors.lastname: Wei
keywords: fermented bamboo shoots; lactobacilli; mRNA; milk; riboflavin; roseoflavin; whey