Kinetics of Zn(2+)-induced brain type creatine kinase unfolding and aggregation

Appl Biochem Biotechnol. 2010 Mar;160(5):1309-20. doi: 10.1007/s12010-009-8574-3. Epub 2009 Mar 11.

Abstract

We studied the effect of Zn(2+) on the folding and aggregation of brain creatine kinase (CK-BB). We developed a method to purify CK-BB from rabbit brain and conducted inhibition kinetics and unfolding studies of CK-BB. Zn(2+) conspicuously aggregated and osmolytes, such as glycine and proline, were able to suppress the formation of aggregates and protect the enzymatic activity against Zn(2+). These results suggest that Zn(2+) might act as a risk factor for CK-BB in the brain under certain conditions, and some osmolytes may help CK-BB to sustain the active state when Zn(2+) is present. Our study provides useful information regarding the effect of Zn(2+) on brain-derived metabolic enzymes, especially those that are putatively related to brain disease. Furthermore, our study suggests that although Zn(2+) may induce CK-BB inactivation and misfolding, the ability of some abundant proteins and osmolytes to chelate Zn(2+) nonspecifically may protect CK-BB and allow it to exist in the active form.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Circular Dichroism
  • Creatine Kinase, BB Form / antagonists & inhibitors
  • Creatine Kinase, BB Form / chemistry*
  • Creatine Kinase, BB Form / isolation & purification
  • Creatine Kinase, BB Form / metabolism*
  • Enzyme Activation / drug effects
  • Fluorescence
  • Glycine / pharmacology
  • Hydrophobic and Hydrophilic Interactions
  • Kinetics
  • Proline / pharmacology
  • Protein Folding*
  • Protein Structure, Quaternary
  • Protein Structure, Secondary
  • Protein Structure, Tertiary
  • Rabbits
  • Time Factors
  • Zinc / pharmacology*

Substances

  • Proline
  • Creatine Kinase, BB Form
  • Zinc
  • Glycine