Resonance Raman fingerprinting of multiheme cytochromes from the cytochrome c3 family

Roberto E. Di Paolo, Patrícia M. Pereira, Inès Gomes, Filipa M.A. Valente, Inês A.C. Pereira, Ricardo Franco

Research output: Contribution to journalArticlepeer-review

4 Citations (Scopus)


Resonance Raman (RR) spectroscopy was used to investigate conformational characteristics of the hemes of several ferricytochromes of the cytochrome c3 family, electron transfer proteins isolated from the periplasm and membranes of sulfate-reducing bacteria. Our analysis concentrated on the low-frequency region of the RR spectra, a fingerprint region that includes vibrations for heme-protein C-S bonds [ν(CaS)]. It has been proposed that these bonds are directly involved in the electron transfer process. The three groups of tetraheme cytochrome c3, analyzed, namely Type I cytochrome c3 (TpIc3s), Type II cytochrome c3 (TpIIc3s) and Desulfomicrobium cytochromes c 3, display different frequency separations for the two ν(C aS) lines that are similar among members of each group. These spectral differences correlate with differences in protein structure observed among the three groups of cytochromes c3. Two larger cytochromes of the cytochrome c3 family display RR spectral characteristics for the ν(CaS) lines that are closer to TpIIc3 than to TpIc3. Two other multiheme cytochromes from Desulfovibrio that do not belong to the cytochrome c3 family display ν(CaS) lines with reverse relative areas in comparison with the latter family. This RR study shows that the small differences in protein structure observed among these cytochrome c3 correlate to differences on the heme-protein bonds, which are likely to have an impact upon the protein function, making RR spectroscopy a sensitive and useful tool for characterizing these cytochromes.

Original languageEnglish
Pages (from-to)217-224
Number of pages8
JournalJBIC Journal of Biological Inorganic Chemistry
Issue number2
Publication statusPublished - Mar 2006


  • Cytochrome c
  • Heme proteins
  • Membrane proteins
  • Resonance Raman spectroscopy


Dive into the research topics of 'Resonance Raman fingerprinting of multiheme cytochromes from the cytochrome c3 family'. Together they form a unique fingerprint.

Cite this