A NEW, NON-SPECIFIC THERMOLABILE NUCLEASE ACTIVE AT LOW TEMPERATURE, IN WIDE PH RANGE AND HIGH CONCENTRATION IN SALTS

The subject matter of this invention is a new thermolabile PPR nuclease or its enzymatically active fragment exhibiting high catalyst activity in difficult reaction conditions (particularly high concentrations of salts and other additives commonly used in the processes of the purification of proteins and viruses, low temperatures and wide range of pH), where the nuclease sequence is SEQ.2 or a sequence that shares at least 40% of its identity. The subject matter of the invention is also the gene encoding PPR nuclease or its enzymatically active fragment; a particle of nucleic acid encoding the PPR nuclease or its enzymatically active fragment; expression plasmid including the sequence of the PPR encoding gene; recombinant strains of Escherichia coli JM109(DE3) pD454-PPR-AmpR and E. coli ArcticExpress (DE3) pD454-PPR-AmpR; the method of PPR nuclease protein production, application of PPR nuclease in processes of purification of recombinant proteins of significantly lower DNA content. As well as for decontamination of reactive reagents and mixtures for PCR, qPCR, RT- PCR, RT-qPCR, RCA, LAMP and NGS in order to obtain higher sensitivity and specificity of relevant genetic analyses; application of the PPR nuclease in processes of virus vector purification (particularly lentiviruses [LV], adenoviruses [AV, AAV] and retroviruses [RV] used in modem gene and cell therapies (chimeric antigen receptor [CAR] T-cell immunotherapy)); application of the PPR nuclease in exosome purification processes for therapeutic or diagnostic purposes; application of the PPR nuclease in processes of recombinant protein purification, particularly enzymes, antibodies, vaccination antigens, products used in cell therapies and other therapeutic proteins. La présente invention concerne une nouvelle nucléase PPR thermolabile ou son fragment enzymatiquement actif présentant une activité catalytique élevée dans des conditions de réaction difficiles (en particulier des concentrations élevées de sels et d'autres additifs couramment utilisés dans les procédés de purification de protéines et de virus, basses températures et une large plage de pH), la séquence de nucléase étant SEQ.2 ou une séquence qui partage au moins 40 % de son identité. L'invention a également pour objet le gène codant pour la nucléase PPR ou son fragment enzymatiquement actif ; une particule d'acide nucléique codant pour la nucléase PPR ou son fragment enzymatiquement actif ; un plasmide d'expression comprenant la séquence