Activity and Survival of the Natural Bacteria under the Stressed Conditions Detected by Bioluminescent Phenotype

스트레스 하의 자연세균의 활성 및 생존의 발광표현형을 이용한 탐지

  • Park, Kyoung-Je (Department of Environmental Science, Hankuk University of Foreign Studies) ;
  • Yoon, Hye-Young (Department of Environmental Science, Hankuk University of Foreign Studies) ;
  • Chun, Se-Jin (Department of Environmental Science, Hankuk University of Foreign Studies) ;
  • Lee, Ho-Sa (Department of Biology, Kyunghee University) ;
  • Lee, Dong-Hun (Division of Life Science, Chungbuk National University) ;
  • Jahng, Deokjin (Department of Chemical Engineering, Myongji University) ;
  • Lee, Kyu-Ho (Department of Environmental Science, Hankuk University of Foreign Studies)
  • 박경제 (한국외국어대학교 환경학과 및 환경과학연구소) ;
  • 윤혜영 (한국외국어대학교 환경학과 및 환경과학연구소) ;
  • 천세진 (한국외국어대학교 환경학과 및 환경과학연구소) ;
  • 이호자 (경희대학교 미생물학과) ;
  • 이동훈 (충북대학교 생명과학부) ;
  • 장덕진 (명지대학교 화학공학과) ;
  • 이규호 (한국외국어대학교 환경학과 및 환경과학연구소)
  • Received : 1998.08.07
  • Accepted : 1998.09.15
  • Published : 1998.09.01

Abstract

To investigate whether the introduced genetic marker is useful to detect the survivalship and activity of the natural bacteria under the stressed conditions, one Gram-negative isolate, KP964 was transformed to the luminous phenotype by transferring luxAB gene. Under the starvation-stress this luminous bacterial culturability (determined by colony-forming-units [CFU] on agar plate) decreased rapidly below the detection limit by 37 days, while its total cell number (determined by AODC) remained almost the same as its initial inocular size. At that time period, the viable cell number was estimated to be 1400 times higher than its CFU number. The bioiuminescence (determined by relative light units [RLU]) produced under the same condition was also monitored and found to decrease more rapidly than the culturability by 5-fold. Under the other stresses, e.g., osmotic shocks, acid shock, and exposure to toxic chemicals, this bacterial strain did not show the reliable correlation between CFU and RLU. These results might not suggest the direct estimation of bioiuminescence from the stressed bacteria be an index of both the survivalship and its activity. However, when the stressed bacterial cells were incubated under the favorable condition by relieving from the existing stress, the potential bioiuminescence (the lag periods before the increase of bioiuminescence, the increase rates of bioiuminescence, and the maximal levels of bioiuminescence) was shown to be highly dependent upon the strengths of the stresses exposed to the bacterial cells. Therefore, analysis of the potential bioiuminescence from the stressed bacteria revealed good relationships with survival as well as activity.

Keywords

starvation;stresses;survival;potential bioluminescence

Acknowledgement

Supported by : 교육부 기초과학연구소