Abstract: We studied charge transfer and dielectric relaxation processes in several materials of biological and organic origin: extracellular matrix of electrogenic bacteria Shewanella oneidensis MR-1, cytochrome c, serum albumin and synthetic melanin. In course of the study we obtained spectra of complex conductivity of materials in frequency range 10-2-1014 Hz measured in temperature range from 5K to 300K. The conductivity spectra were also complemented by heat capacity measurements, element analysis and thermogravimetry. Applying concepts of condensed matter physics, we identify transport mechanisms and a number of energy, time, frequency, spatial and temperature scales in studied materials, which can provide us with deeper insight into the dynamics of proteins and melanin.
Key words: charge transport, cytochrome, melanin, peptides, Shewanella oneidensis, boson peak, nearly constant loss, free charge carriers.