Diversity And Antibiotic Activity Of Myxobacteria In The Daxing’anling Mountains Forest Region Of Inner Mongolia

Myxobacteria are a group of higher prokaryotes with social behavior. They have complicated multicellular behavior and morphogenesis, so they are important to the research of cell differentiation, development and evolution. They have great research value in screening natural drugs, because their metabolites have rich, diverse and novel biological activities.In this study, the denaturing gradient gel electrophoresis was used to analyze the diversity of myxobacteria in 15 soil samples. Escherichia coli inducing method, rabbit dung pellets inducing method, and filter paper inducing method were used to isolate the myxobacteria. The isolated strains were purified with the directly transfering method, second inducing technique and other purification methods. The purified strains were identified by the characteristics of their fruiting body and colony morphology and the molecular biological method. Furthermore, their resistance to bacteria and fungi were also detected.The results indicated that the myxobacteria in these soil samples showed a high diversity, almost covering all the known genera of myxobacteria and some of the unclassified myxobacteria.22 strains of myxobacteria were purified form 88 isolated strains. These strains belonged to Myxococcus, including Myxococcus xanthus (4 strains),Myxococcus flavescens (1 strains),Myxococcus virescens (6 strains),Myxococcus coralloides (3 strains). Myxococcus stipitatus (1 strains), Co rallococcus macrosporuis (3 strains), Corallococcus exiguous (3 strains),Corallococcus coralloides (1 strains).These strains were analyzed for their antibiotic activities. The results indicated that all the purified myxobacteria exhibited one or more antibiotic activities.18 strains of them could inhibit the growth of Escherichia coli DH-5a.6 strains could inhibit the growth of Bacillus subtilis.8 strains could inhibit the growth of Staphylococcus awcus.13 strains could inhibit the growth of Saccharomyces cerevisiae.14 strains could inhibit the growth of Phytophthora infestans.