Fluorescence characteristics of lysine and arginine residues in venom of Naja naja atra

The biological activity of venom of Naja naja atra is related to lysine and arginine residues contained in the venom. Lysine residues in the cenom was tested in a neutral 0.5% ninhydrin solution, and fluorescence wavelength was found to be 450 (407) nm. Arginine residues in the venom was tested in an alkaline 0.5% ninhydrin solution, and the fluorescence wavelength was found to be 450 (407) nm. Arginine residues in the venom was tested in an alkaline 0.5% ninhydrin solution, and the fluorescence wavelength was found to be 504 nm.The excitation and fluorescence spectra of the venom were found to be similar to those of free lysine and arginine. Fluorescence characteristics of the venoms of 6 common snakes in aqueous solution without adding ninhydrin were also examined.