A nucleotide phosphodiesterase with preference for 2',5'-phosphodiester bonds from Ehrlich ascites carcinoma.
We have previously reported that many tumor cell lines express a 5'-nucleotide phosphodiesterase (phosphodiesterase I, EC 3.1.4.1) with properties clearly distinguishable from enzymes of normal tissues (Biochim. Biophys. Acta (1988) 966, 99-106). Such an enzyme with 5'-nucleotide phosphodiesterase activity was purified from Ehrlich ascites carcinoma by measuring the cleavage of thymidine 5'-monophosphate p-nitrophenyl ester (TMP-NP). The enzyme is a soluble protein, has a pH optimum of 7.5, and the molecular mass estimated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis is 67 kDa. The enzyme does not hydrolyze other chromogenic substrates for phosphodiesterases, nor pyrophosphate bond of various nucleotides which are cleaved by 5'-nucleotide phosphodiesterases of normal tissues. But, it hydrolyzes dinucleotides to form 5'-phosphates, and is more active on 2',5'- than on 3',5'-phosphodiester bonds. These results indicate that the TMP-NP splitting enzyme in Ehrlich ascites carcinoma cells is a 2',5'-phosphodiesterase.
Fukazawa
H
H
Institute of Applied Microbiology, University of Tokyo, Japan.
Nishimura
T
T
Suzuki
H
H
D015087:2',3'-Cyclic-Nucleotide Phosphodiesterases / Q000302:isolation & purification* / Q000378:metabolism; D000818:Animals; D002286:Carcinoma, Ehrlich Tumor / Q000201:enzymology*; D002845:Chromatography; D002852:Chromatography, Ion Exchange; D017886:Durapatite; D004591:Electrophoresis, Polyacrylamide Gel; D006882:Hydroxyapatites; D007700:Kinetics; D051379:Mice; D008813:Mice, Inbred ICR; D008970:Molecular Weight; D013379:Substrate Specificity
D006882:Hydroxyapatites; D017886:Durapatite; D015087:2',3'-Cyclic-Nucleotide Phosphodiesterases