Release of Cyt c from the model membrane due to conformational change induced by anticancer palladium complex

Int J Biol Macromol. 2011 Mar 1;48(2):243-8. doi: 10.1016/j.ijbiomac.2010.11.001. Epub 2010 Nov 11.

Abstract

Cytochrome C (Cyt c) is an electron transporting protein that resides within the inter-membrane space of the mitochondria. It plays a critical role as an electron carrier in the process of oxidative phosphorylation and production of cellular ATP. Cyt c is also involved in the apoptosis process and functions as a death messenger. On the other hand, it is well known that the metallo-pharmaceuticals such as palladium complex offer potential as anti-tumor agents to fight cancer. In order to identify the role of anticancer Pd complex in release of Cyt c from the biological membrane, an artificial monolayer was assembled which is able to adsorb Cyt c. A monolayer containing a mixture of two long chain thiols (mercapto-undecanoic acid and mercapto-undecanol) was self-assembled on the surface of a gold electrode. Due to the existence of both hydrophobic and electrostatic interactions between Cyt c and the assembled monolayer, this membrane could be considered as a rough analogue of the biological membrane to study the release of Cyt c by Pd complex. The electrochemical and spectroscopic studies showed that bounding of Pd complex to Cyt c causes a conformational change which leads to the release of Cyt c from the model membrane.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adsorption / drug effects
  • Animals
  • Antineoplastic Agents / pharmacology*
  • Circular Dichroism
  • Cytochromes c / chemistry*
  • Cytochromes c / metabolism*
  • Electrochemical Techniques
  • Electrodes
  • Horses
  • Immobilized Proteins / chemistry
  • Immobilized Proteins / metabolism
  • Membranes, Artificial*
  • Oxazines / metabolism
  • Palladium / chemistry
  • Palladium / pharmacology*
  • Protein Structure, Secondary
  • Spectrometry, Fluorescence
  • Spectrophotometry, Ultraviolet
  • Time Factors

Substances

  • Antineoplastic Agents
  • Immobilized Proteins
  • Membranes, Artificial
  • Oxazines
  • Palladium
  • Cytochromes c
  • nile red