Characterization and expression analysis of the exopolysaccharide gene cluster in Lactobacillus fermentum TDS030603

• Published in: Bioscience, biotechnology, and biochemistry biotechnology, and biochemistry, 2009-12, Vol.73 (12), p.2656-2664
• Main Authors: Dan, T., Obihiro Univ. of Agriculture and Veterinary Medicine, Hokkaido (Japan), Fukuda, K, Sugai Bannai, M, Takakuwa, N, Motoshima, H, Urashima, T
• Format: Article
• Language: English
• Subjects: BACTERIAS ACIDOLACTICAS; BACTERIE LACTIQUE; Biological and medical sciences; Cloning, Molecular; DNA, Complementary - genetics; DNA, Intergenic - genetics; exopolysaccharide gene cluster; EXPRESION GENICA; EXPRESSION DES GENES; FOOD INDUSTRY; Fundamental and applied biological sciences. Psychology; Gene Duplication; GENE EXPRESSION; Gene Expression Regulation, Bacterial; Genomics; http://www.fao.org/aos/agrovoc#c_15990; http://www.fao.org/aos/agrovoc#c_16014; http://www.fao.org/aos/agrovoc#c_27527; http://www.fao.org/aos/agrovoc#c_27583; http://www.fao.org/aos/agrovoc#c_3020; http://www.fao.org/aos/agrovoc#c_33751; http://www.fao.org/aos/agrovoc#c_6097; INDUSTRIA ALIMENTARIA; INDUSTRIE ALIMENTAIRE; LACTIC ACID BACTERIA; Lactobacillus; LACTOBACILLUS FERMENTUM; Lactobacillus fermentum - genetics; Lactobacillus fermentum - metabolism; Multigene Family - genetics; NUCLEOTIDE SEQUENCE; PLASMIDE; PLASMIDIOS; PLASMIDS; Plasmids - genetics; POLISACARIDOS; POLYHOLOSIDE; POLYSACCHARIDES; Polysaccharides, Bacterial - biosynthesis; Polysaccharides, Bacterial - genetics; Polysaccharides, Bacterial - metabolism; SECUENCIA NUCLEOTIDICA; Sequence Analysis, DNA; SEQUENCE NUCLEOTIDIQUE; transposase; Transposases - genetics
• ISSN: 0916-8451; 1347-6947
• DOI: 10.1271/bbb.90502

Part of the exopolysaccharide gene cluster of Lactobacillus fermentum TDS030603 was characterized. It consists of 11,890 base pairs and is located in the chromosomal DNA, 13 open reading frames of which were encoded. Out of the 13 open reading frames, six were found to be involved in exopolysaccharide synthesis; however, five were similar to transposase genes of other lactobacilli, and two were functionally unrelated. Expression analysis revealed that the exopolysaccharide synthesis-related genes were expressed during cultivation. Southern analysis using specific primers for the exopolysaccharide genes indicated that duplication of the gene cluster did not occur. The plasmid-cured strain maintained its capacity for exopolysaccharide production, confirming that the exopolysaccharide gene cluster of this strain is located in the chromosomal DNA, similarly to thermophilic lactic acid bacteria. Our results indicate that this exopolysaccharide gene cluster is likely to be functional, although extensive gene rearrangement occurs.