title: Predicting the oxidation state of cysteines by multiple sequence alignment.
abstract: BACKGROUND
  Protein sequences found in databanks usually do not report post translational covalent modifications such as the oxidation state of cystein (Cys) residues. Accurate prediction of whether a functionally or structurally important Cys occurs in the oxidized or thiol form would be helpful for molecular biology experiments and structure prediction.
  
  
  RESULTS
  A new method is presented for predicting the oxidation state of Cys residues based on multiple sequence alignments and on the observation that Cys tends to occur in the same oxidation state within the same protein. The prediction of the redox state of Cys performs above 82%. The oxidation state of Cys correlates with the cellular location of the given protein within the cell, but the correlation is not perfect (up to 70%). We also perform a statistical analysis of the different redox states of Cys found in secondary structures and buried positions, and of the secondary structures linked by disulfide bonds. The results suggest that the natural borderline lies between the different oxidation states of Cys rather than between the half cystines and cysteins.
  
  
  BACKGROUND
  A web server implementing the prediction method is available at http://guitar.rockefeller.edu/approximately andras/cyspred.html
  
  
  BACKGROUND
  fisera@rockefeller.edu
authors.affiliation: Institute of Enzymology, Biological Research Center, Hungarian Academy of Sciences, Budapest H-1518, PO Box 7, Hungary. fisera@rockefeller.edu
authors.forename: A
authors.initials: A
authors.lastname: Fiser
authors.forename: I
authors.initials: I
authors.lastname: Simon
mesh_terms: D017124:Conserved Sequence; D003545:Cysteine / Q000378:metabolism*; D003553:Cystine; D010084:Oxidation-Reduction; D011237:Predictive Value of Tests; D011499:Protein Processing, Post-Translational; D016415:Sequence Alignment / Q000379:methods*
chemical_list: D003553:Cystine; D003545:Cysteine