MUTANT RECOMBINANT THERMALLY STABLE PHYTASE (VERSIONS), DNA FRAGMENT CODING SAID PHYTASE (VERSIONS) Pichia pastoris STRAIN - PRODUCER OF SAID PHYTASE (VERSIONS) Russian patent published in 2013 - IPC C12N9/16 C12N1/19 

FIELD: chemistry.

SUBSTANCE: disclosed are versions of mutant recombinant phytase PhyA-Cf from Citrobacter freundii bacteria: 1) a version containing an amino acid substitution D144N or D144R, or D144Q, or D144K; 2) a version containing an amino acid substitution V226A or V226G; 3) a version containing an amino acid substitution G343D or G343E, or G343K, or G343R, or G343N; 4) a version containing amino acid substitutions in positions D144 with N, R, Q or K, and in position V226 with A or G; 5) a version containing amino acid substitutions in position D144 with N, R, Q or K, and in position G343 with D, E, K, R or N; 6) a version containing amino acid substitutions in position V226 with A or G, and in position G343 with D, E, K, R or N; 7) a version containing amino acid substitutions in position D144 with N, R, Q or K, and in position V226 with A or G, and in position G343 with D, E, K, R or N. DNA fragments which code said recombinant phytase are provided. Described are strains which produce recombinant phytases Pichia pastoris PhyA-CfDVG and Pichia pastoris PhyA-CfDV, which are deposited in the Russian National Collection of Industrial Microorganisms (VKPM) under number VKPM Y-3495 and VKPM Y-3494, respectively.

EFFECT: invention enables to obtain phytases having thermally stable properties.

13 cl, 2 dwg, 10 ex