Abstract: A bacterial strain of Escherichia coli VNII genetika 472T23, a producer of L-threonine, containing the plasmid PYN7 and a plasmid-free variant of E. coli; strain VNII genetika 472T23, deposited at the American Type Culture Collection under Accesion No. ATCC 98081 and 98082, respectively.

Abstract: A bacterial strain of Escherichia coli BKIIM B-3996, a producer of L-threonine, containing a recombinant plasmid pVIC40 and deposited on Nov. 19, 1987 in the collection of microorganism cultures at the USSR Antibiotics Research Institute under Reg. No. 1867.

Abstract: The present invention provides strains of Escherichia coli which have an isoleucine-tRNA synthetase with an increased Km and no negative feedback inhibition of isoleucine production. These strains are effective for the production of isoleucine in high amounts.

Abstract: A bacterial strain of Escherichia coli BKIIM B-3996, a producere of L-threonine, containing a recombinant plasmid pVIC40 and deposited on Nov. 19, 1987 in the collection of microorganism cultures at the USSR Antibiotics Research Institute under Reg. No. 1867.

Abstract: A method for producing human leukocyte interferon alpha-2 resides in that there is carried out submerged cultivation of a producer strain Pseudomonas species VG-84 carrying a plasmid pVG3 with an inserted gene of human leukocyte interferon alpha-2, said strain being deposited in the collection of microorganism cultures at the USSR Antibiotics Research Institute under Reg. No. 1742; said strain being cultivated in a nutrient medium, containing the sources of carbon and nitrogen, mineral salts and growth stimulants, under aeration in the presence of antibiotics, i.e., streptomycin or tetracycline, or a mixture of both, followed by isolation and purification of the end product.

Abstract: The process for producing L-threonine consists in that there is cultivated a producer of L-threonine in the capacity of which is used the Escherichia coli strain VNIIgenetika M-1 deposited in the Central museum of commercial microorganisms under the All-Union Research Institute for Genetics and Selection of Commercial Microorganisms at a registration No. IIMIIB-1856. The above strain has been selected on the basis of natural variability of the Escherichia coli strain VNIIgenetika VL 334/p YN7), obtained by virtue of the genetic engineering techniques through increasing the dose of mutant genes capable of a higher rate of L-threonine production, by introducing a multicopy hydrid plasmid carrying said genes, into a mutant recipient strain. The abovesaid producer is cultivated on a nutrient medium, containing sources of carbon, nitrogen, and some mineral salts in the presence of an antibiotic penicillin, the resultant biomass being then separated from the culture fluid, whereupon the end product is isolated.

Abstract: A method for constructing strains which produce aminoacids comprising combining of a DNA chromosome fragment of a donor microorganism containing genes controlling the synthesis of a selected aminoacid and having a mutation destroying the negative regulation of the synthesis of this aminoacid with a vector DNA molecule to form a hybrid DNA molecule. Use is made of a vector DNA molecule capable of providing amplification of the hybrid DNA molecule. The resulting hybrid DNA molecule is used for transforming cells of the recipient strain having the mutation blocking the synthesis of the selected aminoacid in this strain and the mutation partly blocking the related step of metabolism of this aminoacid to yield the strain capable of increased productivity of the selected aminoacid.