First time at Proteopedia? Click on the green links: they change the 3D image. Click and drag the molecules. Proteopedia is a 3D, interactive encyclopedia of proteins, RNA, DNA and other molecules. With a free user account, you can edit pages in Proteopedia. Visit the Main Page to learn more.
|1ton, resolution 1.80Å ()|
RAT SUBMAXILLARY GLAND SERINE PROTEASE, TONIN. STRUCTURE SOLUTION AND REFINEMENT AT 1.8 ANGSTROMS RESOLUTION
Tonin is a mammalian serine protease that is capable of generating the vasoconstrictive agent, angiotensin II, directly from its precursor protein, angiotensinogen, a process that normally requires two enzymes, renin and angiotensin-converting enzyme. The X-ray crystallographic structure determination and refinement of tonin at 1.8 A resolution and the analysis of the resulting model are reported. The initial phases were obtained by the method of molecular replacement using as the search model the structure of bovine trypsin. The refined model of tonin consists of 227 amino acid residues out of the 235 in the complete molecule, 149 water molecules, and one zinc ion. The R-factor (R = sigma Fo - Fc/sigma Fo) is 0.196 for the 14,997 measured data between 8 and 1.8 A resolution with I greater than or equal to sigma (I). It is estimated that the overall root-mean-square error in the coordinates is about 0.3 A. The structure of tonin that has been determined is not in its active conformation, but one that has been perturbed by the binding of Zn2+ in the active site. Zn2+ was included in the buffer to aid the crystallization. Nevertheless, the structure of tonin that is described is for the most part similar to its native form as indicated by the close tertiary structural homology with kallikrein. The differences in the structures of the two enzymes are concentrated in several loop regions; these structural differences are probably responsible for the differences in their reactivities and specificities.
Rat submaxillary gland serine protease, tonin. Structure solution and refinement at 1.8 A resolution., Fujinaga M, James MN, J Mol Biol. 1987 May 20;195(2):373-96. PMID:2821276
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
About this Structure
- Fujinaga M, James MN. Rat submaxillary gland serine protease, tonin. Structure solution and refinement at 1.8 A resolution. J Mol Biol. 1987 May 20;195(2):373-96. PMID:2821276