Strong vibronic coupling in heme proteins

Biophys Chem. 1992 Feb;42(2):111-5. doi: 10.1016/0301-4622(92)85001-k.

Abstract

We report the near infrared absorption spectra of cyanomethemoglobin and cyanometmyoglobin in two different solvents (deuterated solutions containing 65% v/v glycerol(OD)3 or 65% v/v ethylene glycol(OD)2). At 25 K the spectra show a clearly resolved fine structure that can be accounted for by considering a strong coupling of the porphyrin-to-iron charge transfer transitions with a single vibrational mode at 365 cm-1. The coupling constants depend on both the specific electronic transition and the protein surrounding the chromophore, indicating once more the specificity of heme globin interactions.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Humans
  • Methemoglobin / analogs & derivatives*
  • Methemoglobin / chemistry
  • Metmyoglobin / analogs & derivatives*
  • Metmyoglobin / chemistry
  • Spectrophotometry, Infrared

Substances

  • cyanomethemoglobin
  • cyanometmyoglobin
  • Metmyoglobin
  • Methemoglobin