Ribonuclease from the hepatopancreas of the red king crab Paralithodes camtschatica
Menzorova, N.I.; Sibirtsev, I.T.; Rasskazov, V.A.
Prikladnaia Biokhimiia i Mikrobiologiia 45(4): 410-414
2009
ISSN/ISBN: 0555-1099 PMID: 19764608 Document Number: 633359
Three enzyme preparations, two acid and one alkaline RNases, were isolated from the hepatopancreas of the red king crab Paralithodes camtschatica using DEAE-cellulose chromatography and gel chromatography. The alkaline RNase was activated by Mg2+ ions and had a pH optimum of 7.2; the acid RNases, a pH optimum of 5.5. The molecular weight of the alkaline RNase was 19 kDa; two acid RNases, 33 and 70 kDa, respectively. The enzymes exhibited a sufficiently high thermostability (IT50 = 53-55 degrees C) and were strongly inhibited by NaCl (IC50, 0.1-0.25 M). The alkaline RNase exhibited no specificity for heterocyclic bases, whereas the acid RNases hydrolyzed poly(U) and poly(A) at maximum rates.