Abstract: An object of the present invention is to provide a microorganism at the elemental composition level, and to provide a technique for providing such a microorganism. The present inventor has succeeded in causing a microorganism to efficiently contain a non-essential element by decreasing the content of an essential nutrient source for the microorganism, a C source, an N source, a P source, or an S source, and by adding an X compound containing the non-essential element as a constitutive element in a manner to make up for the decreased amount, and then culturing the microorganism.

Abstract: An object of the present invention is to provide a microorganism which is novel at the elemental composition level, and to provide a technique for providing such a microorganism. The present inventor has succeeded in causing a microorganism to efficiently contain a non-essential element by decreasing the content of an essential nutrient source for the microorganism, a C source, an N source, a P source, or an S source, and by adding an X compound containing the non-essential element as a constitutive element in a manner to make up for the decreased amount, and then culturing the microorganism.

Abstract: Antibiotic AM-3603 which is also designated as irumamycin is represented by the following formula: ##STR1## This substance is active upon certain Gram-positive bacteria, phytopathogenic fungi and dermatophytes, and is of interest in treating various diseases of humans and animals caused by infectious bacteria and fungi and also useful for agricultural purposes. Antibiotic AM-3603 may be prepared by fermentation, in which a microorganism capable of producing AM-3603 is cultured in a medium to accumulate AM-3603 in the cultured broths, from which AM-3603 is recovered. A preferred strain is Streptomyces sp. AM-3603 (FERM-P 5619; NRRL 12518).

Abstract: A process for converting glycine to L-serine is effected by the use of an aqueous medium containing glycine and microbial cells of a mutant belonging to the genus Nocardia. The mutant is capable of converting glycine to L-serine and has no or lowered ability to decompose L-serine and/or a resistance to at least one metabolic antagonist selected from those of glycine, serine, methionine, glutamine, histidine, leucine, isoleucine, valine, purine, pyrimidine or folic acid. The L-serine is accumulated in the aqueous medium and is recovered therefrom.

Abstract: A process for producing L-lysine by fermentation includes the steps of culturing a strain belonging to the genus Corynebacterium having both an ability to produce L-lysine and a resistance to at least one member selected from the group consisting of aspartic acid analogs and sulfa drugs in a nutrient medium, forming and accumulating L-lysine in the resulting culture liquor and thereafter recovering the L-lysine therefrom.

Abstract: High yields of L-glutamic acid are produced by culturing mutant strains of microorganisms of the genera Pseudomonas and Protaminobacter in a culture medium containing methanol as the principal source of assimilable carbon. L-glutamic acid is accumulated in the culture liquor and is isolated therefrom.