Alternative pathway linked by hydrogen bonds connects heme-Fe of cytochrome c with subunit II-CuA of cytochrome a.

T Ramasarma, D Vaigundan

Journal: Biochemical and biophysical research communications 2019;505(2):445-447

PMID: 30268500

Full Text on Elsevier Science View on PubMed

Abstract

The bridging element for electron transfer in proteins is the hydrogen bond according to the new experimental perspective in preference to carbon-carbon σ-bond presently used. The purpose of this study is to identify an alternative pathway linked by hydrogen bonds suitable for electron transfer from heme-Fe of cytochrome c to subunit II-CuA of cytochrome a. A pathway consisting of 15 delocalized electron systems including peptide bonds, 5 polar groups of side chains of amino acid residues and 8 water molecules, linked by 27 hydrogen bonds, exists between the two metal electron centers of heme-Fe of cytochrome c, cytochrome c and of subunit II-CuA of cytochrome a. Pathways built of delocalized π-electron systems, polar groups and water molecules linked by hydrogen bonds may be considered for intramolecular and intermolecular electron transfer in proteins.

Address: Department of Biochemistry, Bengaluru, 560012, India; Molecular Biophysics Unit, Indian Institute of Science, Bengaluru, 560012, India; Centre for DNA Fingerprinting and Diagnostics, Hyderabad, 500007, India. Electronic address: [email protected].; Molecular Biophysics Unit, Indian Institute of Science, Bengaluru, 560012, India; Department of Cell Biology and Molecular Genetics, Sri Devaraj Urs Academy of Higher Education and Research, Kolar, 563101, India.

DOI: 10.1016/j.bbrc.2018.09.141