[Homologous recombination and chromosomal rearrangements in Escherichia coli strains carrying a heterozygous tandem duplication].

Heterozygous tandem duplications formed in conjugational matings in Escherichia coli provides a convenient model system for studying the evolution of bacterial chromosome. Heterozygous duplications segregate various classes of haploid and diploid recombinants that appear as a result of unequal crossing over between sister chromosomes. In this work, an extended tandem duplication in the deo operon of E.

[Cloning of clusters of erythromycin biosynthesis genes of Streptomyces erythraeus (Saccharopolyspora erythraea)].

The erythromycin resistance gene (ermE) and part of erythromycin biosynthesis genes located in the same cluster with the ermE gene were cloned from S. erythraeus 3 subjected to improvement with respect to erythromycin production. For isolating the erythromycin biosynthesis genes, the plasmid vector pUC18 and the phage vector lambda EMBL3 were used.

[Cloning in Escherichia coli of a mitochondrial DNA fragment from Acremonium chrysogenum containing a region responsible for DNA replication].

A bireplicone plasmid pSU901,4.6 kb in length, was constructed on the basis of plasmid pUC19 and the pstIB fragment, 1.9 kb in length, from mitochondrial DNA of A.

[Study of the structure of amplifying sequence of Streptomyces antibioticus].

A low productive laboratory strain of S. antibioticus and a strain with an increased productivity of oleandomycin derived from it were studied comparatively with using restriction analysis and blotting hybridization. Amplification, site specific integration and segregation of the DNA sequence 32.