Journal of Pure and Applied MicrobiologyVol. 7 No. 2

Aeromonas, Chitinase, Optimization, Screening.

Ying Yang1, Lijuan Zhou2, Bo Zhou1* and Yingliang Zhao1

1Hongyun Honghe Tobacco (Group) Co., Ltd, Kunming - 650 202, China. 2College of Life Sciences, Yunnan University, Kunming - 650 091, China.

Received on 08 October 2012 and accepted on 30 November 2012



One strain of streptococcus thermophilus was tested to be resistant to most current antibiotics and has 100% identical sequence with LMD-9 strain after 16s rRNA analysis. Horizontal gene transfer is a significant phenomenon for the transfer of antibiotic resistance between different bacteria. Thus, the phenomenon was investigated at genome-wide level. The results indicated that a transposase gene was transferred from enterococcus to stremptococcus thermophilus, and plasmid2 was transferred from streptococcus thermophilus to sreptococcus pyrogenes, enterococcus faecium and streptococcus pneumoniae. Furthermore, exopolysaccharide operon gene and glycopeptide antibiotics resistance protein gene (GARPG) were transferred from streptococcus thermophilus to Streptococcus salivarius. GARPG was also found to be transferred from streptococcus thermophilus to Lactococcus lactis. Cell wall thickening was also a feature of broad-range antibiotics resistance in strepotococcus thermophilus. These warned us that the safety status of the dairy bacteria should be taken an all-around consideration. Creating the dairy bacteria without the resistance for common antibiotics will be extremely demanded.

Keywords : Streptococcus thermophilus, Antibiotics resistance, Horizontal gene transfer, Cell wall thickening.