Thermitase and proteinase K: a comparison of the refined three-dimensional structures of the native enzymes.
We compare the three-dimensional structures of thermitase and of proteinase K determined by X-ray crystallography to a resolution of 1.4 and 1.48 A respectively. Both enzymes are relatively stable towards heat and denaturating agents and are representative of a subgroup of subtilisins characterized by a free SH group close to the active site histidine. Even though they have low sequence homology, the overall tertiary structures are highly conserved. The high resolution structures are compared in terms of the overall fold of the molecules, the active sites, the calcium binding sites, disulphide bridge positions, the positions of the charged residues and the solvent structure. Most subtilisins such as thermitase are of prokaryotic origin and proteinase K is up to now the only known eukaryotic structure.
Betzel
C
C
European Molecular Biology Laboratory, Hamburg, FRG.
Teplyakov
A V
AV
Harutyunyan
E H
EH
Saenger
W
W
Wilson
K S
KS
D000595:Amino Acid Sequence; D001665:Binding Sites; D055598:Chemical Phenomena; D002627:Chemistry, Physical; D004220:Disulfides; D019286:Endopeptidase K; D010450:Endopeptidases / Q000378:metabolism; D006639:Histidine; D006358:Hot Temperature; D006860:Hydrogen Bonding; D006863:Hydrogen-Ion Concentration; D007477:Ions; D008958:Models, Molecular; D008969:Molecular Sequence Data; D015394:Molecular Structure; D011487:Protein Conformation; D011489:Protein Denaturation; D012689:Sequence Homology, Nucleic Acid; D012697:Serine Endopeptidases / Q000378:metabolism; D012997:Solvents; D013438:Sulfhydryl Compounds; D014961:X-Ray Diffraction
D004220:Disulfides; D007477:Ions; D012997:Solvents; D013438:Sulfhydryl Compounds; D006639:Histidine; D010450:Endopeptidases; D012697:Serine Endopeptidases; C022728:thermitase; D019286:Endopeptidase K