title: Gene-related strain variation of Staphylococcus aureus for homologous resistance response to acid stress.
abstract: This study investigated the effect of adaptation of Staphylococcus aureus strains to the acidic condition of tomato in response to environmental stresses, such as heat and acid. S. aureus ATCC 13565, ATCC 14458, ATCC 23235, ATCC 27664, and NCCP10826 habituated in tomato extract at 35°C for 24 h were inoculated in tryptic soy broth. The culture suspensions were then subjected to heat challenge or acid challenge at 60°C and pH 3.0, respectively, for 60 min. In addition, transcriptional analysis using quantitative real-time PCR was performed to evaluate the expression level of acid-shock genes, such as clpB, zwf, nuoF, and gnd, from five S. aureus strains after the acid habituation of strains in tomato at 35°C for 15 min and 60 min in comparison with that of the nonhabituated strains. In comparison with the nonhabituated strains, the five tomato-habituated S. aureus strains did not show cross protection to heat, but tomato-habituated S. aureus ATCC 23235 showed acid resistance. In quantitative real-time-PCR analysis, the relative expression levels of acid-shock genes (clpB, zwf, nuoF, and gnd) were increased the most in S. aureus ATCC 23235 after 60 min of tomato habituation, but there was little difference in the expression levels among the five S. aureus strains after 15 min of tomato habituation. These results indicate that the variation of acid resistance of S. aureus is related to the expression of acid-shock genes during acid habituation.
authors.affiliation: Department of Food and Nutrition, Sookmyung Women's University, Seoul 140-742, Republic of Korea.
authors.forename: Soomin
authors.initials: S
authors.lastname: Lee
authors.affiliation: Department of Food and Nutrition, Sookmyung Women's University, Seoul 140-742, Republic of Korea.
authors.forename: Sooyeon
authors.initials: S
authors.lastname: Ahn
authors.affiliation: Department of Food and Nutrition, Sookmyung Women's University, Seoul 140-742, Republic of Korea.
authors.forename: Heeyoung
authors.initials: H
authors.lastname: Lee
authors.affiliation: Microbial Safety Division, Department of Crop Life Safety, National Academy of Agricultural Science, Rural Development Administration, Suwon 441-707, Republic of Korea.
authors.forename: Won-Il
authors.initials: WI
authors.lastname: Kim
authors.affiliation: Microbial Safety Division, Department of Crop Life Safety, National Academy of Agricultural Science, Rural Development Administration, Suwon 441-707, Republic of Korea.
authors.forename: Hwang-Yong
authors.initials: HY
authors.lastname: Kim
authors.affiliation: Microbial Safety Division, Department of Crop Life Safety, National Academy of Agricultural Science, Rural Development Administration, Suwon 441-707, Republic of Korea.
authors.forename: Jae-Gee
authors.initials: JG
authors.lastname: Ryu
authors.affiliation: Microbial Safety Division, Department of Crop Life Safety, National Academy of Agricultural Science, Rural Development Administration, Suwon 441-707, Republic of Korea.
authors.forename: Se-Ri
authors.initials: SR
authors.lastname: Kim
authors.affiliation: Department of Oral Microbiology, College of Dentistry, Wonkwang University, Iksan, Jeonbuk 570-749, Republic of Korea. kheechoi@wonkwang.ac.kr.
authors.forename: Kyoung-Hee
authors.initials: KH
authors.lastname: Choi
authors.affiliation: Department of Food and Nutrition, Sookmyung Women's University, Seoul 140-742, Republic of Korea. yyoon@sookmyung.ac.kr.
authors.forename: Yohan
authors.initials: Y
authors.lastname: Yoon
mesh_terms: D000143:Acids / Q000494:pharmacology*; D000222:Adaptation, Physiological; D002364:Caseins; D024881:Drug Resistance, Bacterial; D015964:Gene Expression Regulation, Bacterial; D005798:Genes, Bacterial; D006358:Hot Temperature; D006863:Hydrogen-Ion Concentration; D018551:Solanum lycopersicum / Q000382:microbiology*; D011492:Protein Hydrolysates; D060888:Real-Time Polymerase Chain Reaction; D013045:Species Specificity; D013211:Staphylococcus aureus / Q000187:drug effects* / Q000235:genetics; D013312:Stress, Physiological
chemical_list: D000143:Acids; D002364:Caseins; D011492:Protein Hydrolysates; C026375:trypticase-soy broth