The Study of Growth Competition between Chromobacterium violaceum and Soil Bacteria

• Main Authors: Tien-Wei Lin, 林天偉
• Other Authors: Yu-Der Wen
• Format: Others
• Language: zh-TW
• Published: 2008
• Online Access: http://ndltd.ncl.edu.tw/handle/25751702652326169959

碩士 === 國立彰化師範大學 === 生物學系 === 96 === Chromobacterium violaceum is a kind of common bacteria in the subtropical and tropical zone soil environment. C. violaceum colony is purple; the reason is in itself secrete a purple compound – violacein. The resent studies have demonstrated that violacein has an antibiotic activity. However, some studies also mentioned that C. violaceum takes a less possession of the environmental bacteria, and is a kind of inferior bacteria in soil environment. In order to understand the role of the violacein in the competition between C. violaceum and soil bacteria, in this study, we investigated the growth and violacein production of C. violaceum in co-culture with six different species named Chryseobacterium indologenes, Serratia marcescens, Enterobacter asburiae, Pantoea agglomerans and Bacillus megaterium. In one-by-one competition, we found the C. indologenes could increase violacein production and promote C. violaceum growth; S. marcescens could reduce violacein production and inhibit C. violaceum growth; E. asburiae and P. agglomerans don’t inhibit C. violaceum growth, but could reduce violacein production. We also found that S. marcescens, E. asburiae and P. agglomerans could decolorlized violacein presented in the culture medium. In group competition experiment, we discovered that when C. indologenes or B. megaterium are in the co-culture system, these two bacteria can prevent S. marcescens from inhibition of C. violaceum growth. Together, these results suggest that violacein can be decolorized by some soil bacteria, therefore, loss its antibiotic activity. This may be the reason why C. violaceum is a weak tendency in soil environment. Moreover, the existence of C. violaceum can be protected as some bacteria (e.g. C. indologenes or Bacillus megaterium) also presences in the same environment.