Binase--
Bacillus pumilus RNase--
endonuclease cleaves the phosphodiester bond between the 3'-guanylic residue and the 5'-OH residue of adjacent
nucleotides with the formation of corresponding intermediate 2',3'-cGMP. Subsequent hydrolysis of 2',3'-cGMP into 3'-phosphate is highly specific and occurs slowly So the question arises about the existing time of that positional isomer during
RNA catalytic cleavage by
binase and about 2',3'-cGMP role in antitumor activity of the
enzyme: In present work by means of
enzyme-linked
immunosorbent assay we established that during catalytic cleavage of
RNA by
binase 2',3'-cGMP is preserved in reaction mixture for an hour, at the same time
phosphodiesterases activation doesn't lead to the total elimination of 2',3'-cGMP. The highest amount of 2',3'-cGMP was observed under the pH 8.5, it reaches nanomolar concentration at initial
RNA concentration of 100-1000 μg/mL. Exogenous 2',3'-cGMP, like its positional isomer 3',5'-cGMP, doesn't trigger an apoptosis of human
lung adenocarcinoma A549 cells, which are sensitive to
binase apoptogenic action. Taking into account data about
binase internalization and activation of mitochondrial pores opening by 2',3'-cyclic
guanosine phosphates we may consider that 2',3'-cGMP can contribute to the apoptosis initiated by
binase only when 2',3'-cGMP is generated intracellularly.