Isolation, Identification And Bacteriostasis Activity Of A Rare Actinomycete

Recently, approximately 70 percent of antibiotics using extensively are produced by various kinds of actinomyces, so many of them take a crucial seat in medicine industry. At the same time they are used widespread in micro-ecosystem preparation which is made up by the normal microorganisms or same material that can promote the prowth of microorganisms. However, there is extremely perplexing relationship among various microorganisms in ecosystem,so when we chose which strain to be used in, so we need to carry out a series of cross-inoculation test to study the interaction of plants'rhizospere microorganisms which include the relationship between plants and microorganisms, microorganisms and other microorganisms, soils and microorganisms. Only in this way, we can make the best choice. In addition, there will be same hybridization and mutation in a low probability during the multiplicative process of strains, and this may result in some change in their shape character and physiological effects of action, so any time we need to detect this phenomenon to ensure the secruity and effectivity of micro-ecosystem preparation.Isolated a series of different strains from the compound organic fertilizers, then cultivate with the GNW and HP2 which preservated by our lab, and detect purpose strains exhibiting bacteriostasis and antineoplastic activity; the isolated bacterial strain was identified by morphological, physiological and biochemical characters respectively, and 16S rRNA of the strain was sequenced. The antibacterial activity mensuration of fermenting liquor was to detect bacteriostasis activity and antineoplastic activity. The results of identification demonstrated that an actinomycete GNF1 exhibiting bacteriostasis activity was Streptomyces, and there was active constitutent in its metabolic products which can strongly inhibited by the growth of GNW, HP2 and some pronucleus pathogenic microorganism.Objective:The research aimed to find whether there are some exhibiting bacteriostasis activity and antineoplastic activity in the mixed type microorganisms organic fertilizer by studying the interaction between the strains in organic fertilizer and soils inherent strains, then we can ptimize prescription of stains, and initiatorily study its mechanism of bacteriostas and antineoplastic activity.Method:1. To isolate some strains from the micro-ecosystem preparations that have been sold in the market by selective medium, then take prefractionation basised on the difference of morphology;2. Cultivated with the GNW and HP2 which preservated by our lab, then by prefracti-onation and validate test of cup-plate method to detect purpose strains exhibiting bac-teriostasis;3. The isolated bacterial strain was identified by morphological, physiological and biochemical characters respectively, and 16S rRNA of the strain was sequenced;4. Antibacterial activity mensuration of fermenting liquo was to detect bacteriostasis activity and antivirus activity.5. MTT was performed to establish the antineoplastic effects of the extract of GNF1 fermenting liquor on HepG2 cells.Result:1. Six strains were separated initially by the selective medium.2. GNF1 can strongly inhibit the growth of GNW, HP2 when they are co-cultivated; validated this bacteriostasis by cup-plate method.3. GNF1 has typal characteristic of the Streptomyces:hypha in medium has much of branch, no fragmentation, abundant aerial hypha, straight and long spore chain with little wave,spore show prismatical. It can growth well in many medium, aerial hypha is white to almond yellow, pink or empurple when maturation.4.GNF1 can growth from 10℃to 40℃, and 28℃it's the best temperature optimum. pH:6.0-8.5,7.0 is the best. NaCl:0.2-0.5 mol/L. Gelatinolyt,icamylolysis,H2S produce are negtive; it can not hydrolyse Tween20 and Casein; melanin produce, milk peptonize,cellulose hydrolyse and notrates reduction test is negtive. Carbon and Nitrogen source that GNF1 can utilize is varied.There are glycine, Aspartic Acid, glucose, galactose, xylose and ribose,and so on,in the GNF1's cell hydrolyse output. 5. Choosed GNFl's genome DNA as the amplification template of PCR, and used bacteria 16S rRNA current primer to amplificate 16S rRNA.6. There are only 6bp is different between GNF1 and Streptonmyces microflavus by the phylogeny cladogram which was builded on the basis of 16SrRNA series. Their homo logy is 99.6%, so we tentatively set on GNF1 as Streptonmyces microflavus.7. The extract of GNF1 fermenting liquor can inhibit the growth of Escherichia coli,Staphylococcus aureaus, Proteus vulgaris, and some pronucleus pathogenic microorganism. It's bacteriostasis effect get close to the streptomycin's, and obviously higher than wild type; it's antifungi activity comparatively low, but also can inhibit the growth of some fungi, such as Geotrichum candidum, C.albicans, C. krusei and Trichophy tonrubrum at a low level; antivirus test is negative, so we guess it has not the activity of antivirus.8. The extract of GNF1 fermenting liquor can inhibit the cell viability of HepG2 cells, but not to the L-02 cells.We hypothesize that the extract of GNF1 fermenting liquor can contain some antineoplastic composes.Conclusion:1. One strain possessed bacterio stasis was successfully separated which is a mutant of Streptonmyces microflavus.and it's active material possess a cyclopaedic bacteriostas-is that can inhibit some pronucleus pathogenic microorganism.2. In view of the bacteriostasis activity of GNF1, we need to study and research its mechanism and develop correlated microecosystem preparation or antineoplastic drugs.3. The correlative index should be established of the mixed type microorganisms organic fertilizer, and it should be detected consistently to find out whether there are some mutations in strains, then we must reject this kind of strain. Besides, in view of this strain's bacteriostasis activity, it is worth to lucubrating.