Expression of genes involved in exopolysaccharide synthesis in Lactiplantibacillus plantarum VAL6 under environmental stresses

• Published in: Archives of microbiology Vol. 203; no. 8; pp. 4941 - 4950
• Main Authors: Le, Trung-Son, Nguyen, Phu-Tho, Nguyen-Ho, Song-Hao, Nguyen, Tang-Phu, Nguyen, Thi-Tho, Thai, My-Ngan, Nguyen-Thi, To-Uyen, Nguyen, Minh-Chon, Hoang, Quoc-Khanh, Nguyen, Huu-Thanh
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.10.2021; Springer Nature B.V
• Subjects: Amplification; Bacteria; Biochemistry; Biomedical and Life Sciences; Biosynthesis; Biotechnology; Carbon dioxide; Cell Biology; Ecology; Environmental factors; Environmental stress; Exopolysaccharides; Gene expression; Genes; Lactic acid; Lactic acid bacteria; Lactiplantibacillus plantarum; Life Sciences; Microbial Ecology; Microbiology; Monosaccharides; Original Paper; pH effects; Sodium chloride; Stresses; qPCR; Real-time PCR; Gene expression; Environmental stress
• ISSN: 0302-8933; 1432-072X
• DOI: 10.1007/s00203-021-02479-0

Environmental factors can alter exopolysaccharide biosynthesis in lactic acid bacteria (LAB). To further clarify this potential relationship, the mRNA expression of genes involved in exopolysaccharide synthesis such as glmU, pgmB1, cps4E, cps4F , cps4J , and cps4H in Lactiplantibacillus plantarum VAL6 under different conditions including temperature, pH, sodium chloride (NaCl), and carbon dioxide (CO 2 ) intensification culture was studied. The transcriptomic data revealed that the exposure of L. plantarum VAL6 at pH 3 increased the expression level of cps 4H but decreased the expression levels of pgmB1 and cps4E . Under pH 8, cps4F and cps4E were significantly upregulated, whereas pgmB1 was downregulated. Similarly, the expression levels of cps4F , cps4E , and cps4J increased sharply under stresses at 42 or 47 °C. In the case of NaCl stress, glmU , pgmB1 , cps4J , and cps4H were downregulated in exposure to NaCl at 7 and 10% concentrations while cps4E and cps4F were upregulated at 1 h of 10%-NaCl treatment and at 5 h of 4%-NaCl treatment. Remarkably, CO 2 intensification culture stimulated the expression of all tested genes. In addition, simultaneous changes in expression of cps 4E and cps 4F under environmental challenges may elicit the possibility of an association between the two genes. These findings indicated that the expression level of eps genes is responsible for changes in the yield and monosaccharide composition of exopolysaccharides under environmental stresses.