Stimulating Actinomycetes To Produce Antibiotics And Application In New Method Screening Antibiotic

The side-effect of antibiotics and resistance of pathogenic strains compel new antibiotics to continually replace old ones. Traditional screen methods for antibiotics frequently cause higher repetition rate and lower efficency. So, to obtain new antibiotic, one has to start with screen pattern, antibiotic source, biotechnology application and extract of fermentation products, ect.Escheria coli, Bacillus subtilis, Aerobacter aerogenes, Staphylococcus aureus, Saccharomyces cerevisiae, Candida albicans used in traditional pattern were treated by physical and chemical mutagen, then obtained eight mutants which are distinctly different resistance to clinical antibiotics most in use, such as β -lactam, tetracycline, aminoglycoside, macrolide, polyene macrolide and actidione. The screening pattern consisting of the mutants and synthetical paper chromatography by many kinds of solvent was testified to be able to provide scientific basis for early distinguishing different antibiotic group.Sixty actinomycetes with the morphology of Nocardia were isolated from the rice field of high humic acid and low pH value. No.20, one strain of the sixty, can produce one new antibiotic, two strains No. 12 and No.38 were testified to be nature inactive wild.The inactive wild strains No. 12 and No.38 were treated by ethidium bromide (EB), diethyl sulfate (DES), ultraviolet ray, and their protoplastwere fused with killed protoplast of Nocardia mediterranei AS.4895 (met) secreted rifomycin. The result showed the two original strains were stimulated to active. The variants can produce antibiotics. Among these variants, No.12-12 was obtained by the complex mutagenization of DES and EB, No.38-86,No.12-103,No.12-6 by EB and UV, and F_12-1,F_38-1,F_38-2...