Abstract: A mutant of the Tritirachium album proteinase K zymogen containing a mutation that increases the efficiency of expression in yeast cells and facilitates the inactivation of mature proteinase K under stress and a method of obtaining it.

Abstract: The subject of the invention is a freeze-dried and ready-for-lyophilization form of the recombinant human RNase inhibitor of SEQ ID NO 1 of the wild type variant in full size (50 kDa), which retains the properties of a recombinant human RNase inhibitor and can be used in the industrial applications including molecular biology and in vitro diagnostics. The developed formulation as well as the freeze-dried form of the recombinant human RNase inhibitor was successfully prepared for the first time in the full size variant. The subject of the invention is a freeze-dried variant of a recombinant human RNase inhibitor and the process of its production resulting in the formation of a powdered form of an RNase inhibitor, which maintains its functionality and increases its stability. Additionally, a dedicated liquid formulation ready for the freeze-drying process was developed.

Abstract: 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.