title: Association of mutation patterns in GyrA and ParC genes with quinolone resistance levels in lactic acid bacteria.
abstract: The quinolone resistance of 19 lactic acid bacterial strains belonging to the genera Enterococcus and Lactobacillus isolated from the natural fermented koumiss and yoghurt were investigated. The objective of this study was to determine the quinolone resistance levels and to explore the association of the resistance with the mutation patterns in gyrA and parC genes, as is currently recommended by the Food and Agriculture Organization/World Health Organization Joint Expert Committee in Guidelines for Evaluation of Probiotics in Food for probiotic lactic acid bacteria drug resistance in 2001. The Oxford Cup method and double-tube dilution method were used to determine the quinolone resistance levels of the isolated strains. Generally, all of the 19 strains showed resistance towards norfloxacin and ciprofloxacin when the Oxford cup method was used, whereas the incidence was lower (to norfloxacin 89.5% and to ciprofloxacin 68.4%) when minimum inhibitory concentration breakpoints (CLSI M100-S23) were tested. Furthermore, gene sequencing was conducted on gyrA and parC of topoisomerase II of these isolated strains. The genetic basis for quinolone resistance may be closely related to mutations in gyrA genes as there were 10 mutation sites in amino-acid sequences encoded by gyrA genes in 10 quinolone resistance strains and 14 mutation sites in Enterococcus durans HZ28, whereas no typical mutations were detected in parC genes.
authors.affiliation: Food Science and Engineering College, Inner Mongolia Agricultural University, Hohhot, China.
authors.forename: Shaoying
authors.initials: S
authors.lastname: Li
authors.affiliation: Food Science and Engineering College, Inner Mongolia Agricultural University, Hohhot, China.
authors.forename: Zhen
authors.initials: Z
authors.lastname: Li
authors.affiliation: Food and Cosmetic Authority of Inner Mongolia, Hohhot, China.
authors.forename: Wan
authors.initials: W
authors.lastname: Wei
authors.affiliation: Food Science and Engineering College, Inner Mongolia Agricultural University, Hohhot, China.
authors.forename: Chunyan
authors.initials: C
authors.lastname: Ma
authors.affiliation: Food Science and Engineering College, Inner Mongolia Agricultural University, Hohhot, China.
authors.forename: Xiaomin
authors.initials: X
authors.lastname: Song
authors.affiliation: College of Life Science, Inner Mongolia Agricultural University, Hohhot, China.
authors.forename: Shufen
authors.initials: S
authors.lastname: Li
authors.affiliation: College of Science, Inner Mongolia Agricultural University, Hohhot, China.
authors.forename: Wenying
authors.initials: W
authors.lastname: He
authors.affiliation: Food Science and Engineering College, Inner Mongolia Agricultural University, Hohhot, China.
authors.forename: Jianjun
authors.initials: J
authors.lastname: Tian
authors.affiliation: Food Science and Engineering College, Inner Mongolia Agricultural University, Hohhot, China.
authors.forename: Xiaoyan
authors.initials: X
authors.lastname: Huo
mesh_terms: D000595:Amino Acid Sequence; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D002939:Ciprofloxacin / Q000494:pharmacology; D043302:Cultured Milk Products / Q000382:microbiology; D027081:DNA Gyrase / Q000235:genetics*; D027101:DNA Topoisomerase IV / Q000235:genetics*; D004250:DNA Topoisomerases, Type II / Q000235:genetics; D024881:Drug Resistance, Bacterial / Q000235:genetics*; D016983:Enterococcus / Q000187:drug effects / Q000235:genetics / Q000302:isolation & purification; D019344:Lactic Acid / Q000378:metabolism*; D007778:Lactobacillus / Q000187:drug effects / Q000235:genetics / Q000302:isolation & purification; D008826:Microbial Sensitivity Tests; D009154:Mutation; D009643:Norfloxacin / Q000494:pharmacology; D015363:Quinolones / Q000494:pharmacology*; D015014:Yogurt / Q000382:microbiology
chemical_list: D000900:Anti-Bacterial Agents; D015363:Quinolones; D019344:Lactic Acid; D002939:Ciprofloxacin; D027101:DNA Topoisomerase IV; D027081:DNA Gyrase; D004250:DNA Topoisomerases, Type II; D009643:Norfloxacin