Open AccessCrystallization and preliminary X‐ray diffraction studies of trypsin‐like proteases from the gastric fluid of the marine crab Cancer pagurus
Author(s) -
Hehemann JanHendrik,
Redecke Lars,
Perbandt Markus,
Saborowski Reinhard,
Betzel Christian
Publication year - 2007
Publication title -
acta crystallographica section f
Language(s) - English
Resource type - Journals
ISSN - 1744-3091
DOI - 10.1107/s1744309107008524
Subject(s) - orthorhombic crystal system , proteases , crystallization , crystallography , trypsin , chemistry , molecule , chromatography , enzyme , crystal structure , biochemistry , organic chemistry
The digestive fluid of the marine crab Cancer pagurus (Decapoda, Brachyura) contains highly stable proteases which display enhanced activity in aqueous mixtures of organic solvents. Three trypsins were isolated from the gastric fluid and two of them, C.p. TryII and C.p. TryIII, were purified to homogeneity by anion‐exchange chromatography and crystallized by hanging‐drop vapour diffusion. Diffraction data were collected at a synchrotron to 0.97 and 3.2 Å resolution, respectively. The crystal of C.p. TryII belongs to the orthorhombic space group P 2 1 2 1 2 1 , with unit‐cell parameters a = 52.06, b = 62.00, c = 71.66 Å. Based on the Matthews coefficient, one protein molecule per asymmetric unit is suggested. In contrast, crystals of C.p. TryIII, which belong to the cubic space group P 2 1 3 with unit‐cell parameters a = b = c = 215.4 Å, are assumed to contain 12 molecules per asymmetric unit.