title: Entropy of never born protein sequences.
abstract: BACKGROUND
  A Never Born protein is a theoretical protein which does not occur in nature. The reason why some proteins were selected and some were not during evolution is not known. We applied information theory to find similarities and differences in information content in Never Born and natural proteins.
  
  
  RESULTS
  Both block and relative entropies are similar what means that both protein kinds contain strongly random sequences. An artificially generated Never Born protein sequence is closely as random as a natural one.
  
  
  CONCLUSIONS
  Information theory approach suggests that protein selection during evolution was rather random/non-deterministic. Natural proteins have no noticeable unique features in information theory sense.
authors.affiliation: Information Technology Department, Faculty of Physics, Astronomy and Applied Computer Science, Jagiellonian University, 4 Reymonta Street, Cracow, 30-059 Poland.
authors.forename: Grzegorz
authors.initials: G
authors.lastname: Szoniec
authors.forename: Maciej J
authors.initials: MJ
authors.lastname: Ogorzalek
keywords: Block entropy; Kullback-Leibler divergence; Never born protein; Origin of life; Relative entropy