title: Circular dichroism comparative studies of two bacterial collagenases and thermolysin.
abstract: The recently isolated and purified collagenase produced by Achromobacter iophagus, the collagenase from Clostridium histolyticum, and thermolysin, three enzymes having common properties, were studied by circular dichroism. From the spectra of the aqueous solutions obtained in the peptide region, the fraction of alpha helix, beta sheet and aperiodic segments in the three proteins could be estimated. Good similarity was found between Achromobacter collagenase and thermolysin, which both contain a high fraction of alpha helix. Side-chain contributions were analyzed in the aromatic region of thespectra: effects of pH and of organic solvents were observed, showing the strong influence of surroundings on the stabilization of the proteins.
mesh_terms: D000421:Alcaligenes / Q000201:enzymology; D002942:Circular Dichroism; D003013:Clostridium / Q000201:enzymology; D006146:Guanidines / Q000494:pharmacology; D006863:Hydrogen-Ion Concentration; D003012:Microbial Collagenase / Q000032:analysis*; D010455:Peptides / Q000032:analysis; D011487:Protein Conformation / Q000187:drug effects; D011489:Protein Denaturation / Q000187:drug effects; D012967:Sodium Dodecyl Sulfate / Q000494:pharmacology; D012997:Solvents / Q000494:pharmacology; D013820:Thermolysin / Q000032:analysis*; D014270:Trifluoroethanol / Q000494:pharmacology
chemical_list: D006146:Guanidines; D010455:Peptides; D012997:Solvents; D012967:Sodium Dodecyl Sulfate; D014270:Trifluoroethanol; D013820:Thermolysin; D003012:Microbial Collagenase