The interaction of 8-anilinonaphthalene-1-sulfonate with His-47 of Taiwan cobra phospholipase A2 perturbing by the binding of calcium ion

Biochem Mol Biol Int. 1996 May;39(2):335-42. doi: 10.1080/15216549600201361.

Abstract

The 8-anilinonaphthalene-1-sulfonate (ANS) fluorescence intensity of ANS-Naja naja atra (Taiwan cobra) phospholipase A2 (PLA2) complex increased with the addition of Ca2+, but the observed fluorescence enhancement markedly decreased after methylation of His-47 in PLA2 molecule. However, the binding affinities of methylated PLA2 for ANS and Ca2+ were similar to or even greater than those observed with native PLA2. These results, together with the finding that ANS electrostatically interacted with His-47 of PLA2, suggest that the increase in the intensity of ANS fluorescence upon the addition of Ca2+, in part, arises from the ionic interaction of His-47 with ANS being perturbed by the binding of Ca2+.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Anilino Naphthalenesulfonates / metabolism*
  • Animals
  • Calcium / metabolism*
  • Elapid Venoms / enzymology*
  • Fluorescence
  • Fluorescent Dyes
  • Histamine / metabolism
  • Phospholipases A / metabolism*
  • Phospholipases A2

Substances

  • Anilino Naphthalenesulfonates
  • Elapid Venoms
  • Fluorescent Dyes
  • 1-anilino-8-naphthalenesulfonate
  • Histamine
  • Phospholipases A
  • Phospholipases A2
  • Calcium