-transparent.png){kind=logo}
A venom exonuclease 'phosphodiesterase' (E.C. 3.1.4.1) has been purified from Cerastes cerastes venom by a combination of gel filtration on Sephadex G-100 superfine and ion exchange chromatography on DEAE-Sepharose. The enzyme showed a single band on PAGE and SDS-PAGE and had a molecular weight of 110,000. The final preparation was purified 28 fold. It had no carbohydrate and it did not have protease or 5'-nucleotidase activities. Optimum temperature for enzyme activity was 56 degrees C. The enzyme was rapidly inactivated when pre-incubated above 40 degrees C. Energy of activation (Ea) was calculated to be 0.913. The optimum pH was 9.0. Cysteine, glutathione, dithiothreitol, 2-mercaptoethanol, ADP and AMP inhibited the enzyme. Cysteine caused a non-competitive inhibition, while ADP showed a competitive inhibition. EDTA at a concentration of 0.5 mM caused complete inhibition of the enzyme, which could be reversed by the addition of Ca2+ or Mn2+.
H Y Halim, and
E A Shaban, and
M M Hagag, and
E W Daoud, and
M F el-Asmar
January 1986,
Toxicon : official journal of the International Society on Toxinology,
H Y Halim, and
E A Shaban, and
M M Hagag, and
E W Daoud, and
M F el-Asmar
July 1995,
Biochimica et biophysica acta,
H Y Halim, and
E A Shaban, and
M M Hagag, and
E W Daoud, and
M F el-Asmar
April 1986,
Thrombosis research,
H Y Halim, and
E A Shaban, and
M M Hagag, and
E W Daoud, and
M F el-Asmar
January 1981,
Toxicon : official journal of the International Society on Toxinology,
H Y Halim, and
E A Shaban, and
M M Hagag, and
E W Daoud, and
M F el-Asmar
March 1986,
Thrombosis research,
H Y Halim, and
E A Shaban, and
M M Hagag, and
E W Daoud, and
M F el-Asmar
February 1988,
Biochemical and biophysical research communications,
H Y Halim, and
E A Shaban, and
M M Hagag, and
E W Daoud, and
M F el-Asmar
January 1990,
Toxicon : official journal of the International Society on Toxinology,
H Y Halim, and
E A Shaban, and
M M Hagag, and
E W Daoud, and
M F el-Asmar
January 1990,
Immunopharmacology,
H Y Halim, and
E A Shaban, and
M M Hagag, and
E W Daoud, and
M F el-Asmar
August 2009,
Comparative biochemistry and physiology. Toxicology & pharmacology : CBP,
H Y Halim, and
E A Shaban, and
M M Hagag, and
E W Daoud, and
M F el-Asmar
December 2012,
Toxicon : official journal of the International Society on Toxinology,
