Review and Future Development of New Culture Methods for Unculturable Soil Bacteria

난배양성 토양세균을 위한 신배양기술의 고찰과 향후 발전 방향

  • Kim, Jai-Soo (Department of Life Science, Kyonggi University)
  • 김재수 (경기대학교 자연과학대학 생명과학과)
  • Received : 2011.08.17
  • Accepted : 2011.12.14
  • Published : 2011.09.30

Abstract

This review describes the characteristics of various unculturable soil bacteria, successfully-cultivating examples of those bacteria, and the diverse factors to be considered for successful cultivation. Most importantly, the selection of proper media is very important because unculturable bacteria demand different types of nutrients at various concentrations of substrates, nitrogens and phosphorus. To develop a new medium to successfully culture unculturable bacteria from soil, molecular ecological studies should be combined together. The inoculum size on a plate is also important: less than 50 bacterial cells are recommended to be plated on a single culture plate. The environmental factors such as pH and salt concentration of the medium need to be adjusted as similar as possible to mimic the original soil environments, and the trial of the various temperatures and extended period of cultivation are better. Since one cannot simply tell about which one was unculturable among a great number of colonies grown on a newly developed medium, some suitable detection methods and fast identification methods are required. Many soil bacteria live with cooperation one another in their communities, so that enrichment such as coculture of using other bacterial metabolites and subsequent pure cultures can also guarantee successful cultivation of the previously uncultured bacteria in soil. Here, this review will discuss for the future perspectives to culture the unculturable soil bacteria.

Keywords

coculture;metagenomics;new culture method;soil bacteria;unculturable

Acknowledgement

Supported by : 경기대학교

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