To develop the procedures for obtaining new microbial metabolites through screening, chemical modification, biotransformation, interspecific protoplast fusion and gene cloning. The production of new metabolites with new isolates and/or new test methods is carried out during Screening-Selection process. Chemical modification and biotransformation are applied for change in a chemical molecule by means of a microbial or enzyme reaction of known microbial substances. We also use interspecific protoplast fusion, which is a recombination of genetic information from rather closely related producer strains to obtain new or hybrid substances. In this process genes may be transferred between unrelated strains which are producers of known substances.