[Biogenesis and regulation of biosynthesis of erythromycins in Saccharopolyspora erythraea: a review].

Data on the structure and stages of biosynthesis of erythromycins, relating to (1) successive addition of L-mycarose and D-desosamine to the lactones erythronolide B and mycarosyl-erythronolide B, respectively, and (2) biotransformation of erythromycin D to erythromycin A, are presented. Pathways of biosynthesis of L-mycarose, D-desosamine, and methylmalonyl-CoA and methylpropionyl-CoA precursors of erythronolide B are reviewed, along with the properties of genes coding the enzymes involved. Possible mechanisms of biochemical and gene regulation of erythromycin biosynthesis in Saccharopolyspora erythraea are discussed, including the role of factors ensuring predominant formation of the target product, erythromycin A.

[Isolation and characterization of Saccharopolyspora erythraea mutants, resistant to chloramphenicol].

Formation of chloramphenicol resistant (CMr) spontaneous and nitroso-ethyl-urea-induced mutants of S.erythraea, an organism producing erythromycin, was studied. The mutants differed by the level of the chloramphenicol resistance (10 to 40 micrograms/ml).

[The isolation and characteristics of mutants of the Saccharopolyspora erythraea strain resistant to thiostrepton].

The formation of thiostreptone resistant spontaneous and nitrosoguanidine-induced mutants in the erythromycin-producing organism Saccharopolyspora erythraea was investigated. The investigated collection of the mutants was heterogeneous by the level of the thiostreptone resistance (2.5 to 20 micrograms/ml).

[Isolation and characterization of genetic recombinants in protoplast fusion in Saccharopolyspora erythraea].

Formation of genetic recombinants after conjugation and protoplast fusion in Saccharopolyspora erythraea, an organism producing erythromycin, was studied comparatively. After the protoplast fusion the frequency of all the classes of the haploid recombinants increased 10 to 460 times by comparison with the conjugation. The protoplast fusion was characterized by higher diversity of the recombinant classes, up to 45.