3I74

Crystal Structure of the plant subtilisin-like protease SBT3 in complex with a chloromethylketone inhibitor

Summary for 3I74

• Entry DOI: 10.2210/pdb3i74/pdb
• Related: 3I6S
• Related PRD ID: PRD_001030
• Descriptor: Subtilisin-like protease, ACE-PHE-GLU-LYS-ALA chloromethylketone INHIBITOR, 2-acetamido-2-deoxy-beta-D-glucopyranose-(1-4)-2-acetamido-2-deoxy-beta-D-glucopyranose, ... (6 entities in total)
• Functional Keywords: subtilisin-like protease, pa-domain, fn3-domain, chloromethylketone inhibitor, hydrolase-hydrolase inhibitor complex, hydrolase/hydrolase inhibitor
• Biological source: Solanum lycopersicum (tomato)
• Total number of polymer chains: 4
• Total formula weight: 143479.09

Authors

Rose, R.,Ottmann, C. (deposition date: 2009-07-08, release date: 2010-01-19, Last modification date: 2024-10-30)

Primary citation

Ottmann, C.,Rose, R.,Huttenlocher, F.,Cedzich, A.,Hauske, P.,Kaiser, M.,Huber, R.,Schaller, A.
Structural basis for Ca2+-independence and activation by homodimerization of tomato subtilase 3.
Proc.Natl.Acad.Sci.USA, 106:17223-17228, 2009

PubMed Abstract: Subtilases are serine proteases found in Archae, Bacteria, yeasts, and higher eukaryotes. Plants possess many more of these subtilisin-like endopeptidases than animals, e.g., 56 identified genes in Arabidopsis compared with only 9 in humans, indicating important roles for subtilases in plant biology. We report the first structure of a plant subtilase, SBT3 from tomato, in the active apo form and complexed with a chloromethylketone (cmk) inhibitor. The domain architecture comprises an N-terminal protease domain displaying a 132 aa protease-associated (PA) domain insertion and a C-terminal seven-stranded jelly-roll fibronectin (Fn) III-like domain. We present the first structural evidence for an explicit function of PA domains in proteases revealing a vital role in the homo-dimerization of SBT3 and in enzyme activation. Although Ca(2+)-binding sites are conserved and critical for stability in other subtilases, SBT3 was found to be Ca(2+)-free and its thermo stability is Ca(2+)-independent.

PubMed: 19805099
DOI: 10.1073/pnas.0907587106

Experimental method

X-RAY DIFFRACTION (2.6 Å)