The Metal Ion Dependence of Phospholipase C From Bacillus Cereus

Biochim Biophys Acta. 1975 Jun 24;391(2):326-33. doi: 10.1016/0005-2744(75)90256-9.

Abstract

1. The zinc content and metal ion dependence of phospholipase C(phosphatidylcholine cholinephosphohydrolase, EC 3.1.4.3) from Bacillus cereus have been examined. 2. The native enzyme contained about 2 atoms of tightly bound zinc/molecule. 3. Incubation of the enzyme with EDTA or with o-phenanthroline caused inactivation. The inactivation was accompanied by the removal of one zinc atom from the enzyme and could be fully reversed by the addition of Zn2+ or Co2+ to the enzyme and partly reversed by Mn2+ or Mg2+. 4. Prolonged exposure to o-phenanthroline removed the second zinc atom also and produced an enzyme species which was reactivated by Zn2+ only. Full reactivation was accompanied by the binding of about two zinc atoms to the enzyme. 5. The results are consistent with the view that phospholipase C is a zinc metalloenzyme.

MeSH terms

  • Bacillus cereus / drug effects
  • Bacillus cereus / enzymology*
  • Binding Sites
  • Cobalt / pharmacology*
  • Edetic Acid / pharmacology
  • Kinetics
  • Magnesium / pharmacology*
  • Manganese / pharmacology*
  • Mutation
  • Phenanthrolines / pharmacology
  • Phospholipases / metabolism*
  • Protein Binding
  • Time Factors
  • Zinc / pharmacology*

Substances

  • Phenanthrolines
  • Cobalt
  • Manganese
  • Edetic Acid
  • Phospholipases
  • Magnesium
  • Zinc