3afg is a 2 chain structure with sequence from Thermococcus kodakarensis. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.
Publication Abstract from PubMed
Tk-SP is a hyperthermostable subtilisin-like serine protease from Thermococcus kodakaraensis and is autoprocessed from its precursor (Pro-Tk-SP) with N- and C-propeptides. The crystal structure of the active-site mutant of Pro-Tk-SP lacking C-propeptide, ProN-Tk-S359A, was determined at 2.0 A resolution. ProN-Tk-S359A consists of the N-propeptide, subtilisin, and beta-jelly roll domains. Two Ca(2+) ions bind to the beta-jelly roll domain. The overall structure of ProN-Tk-S359A without the beta-jelly roll domain is similar to that of the bacterial propeptide:subtilisin complex, except that it does not contain Ca(2+) ions. To analyze the role of the beta-jelly roll domain of Tk-SP, we constructed a series of the active-site mutants of Tk-SP with (Tk-S359A/C) and without (Tk-S359A/CDeltaJ) beta-jelly roll domain. Both Tk-S359C and Tk-S359CDeltaJ exhibited protease activities in gel assay, indicating that the beta-jelly roll domain is not required for folding or activity. However, the T(m) value of Tk-S359ADeltaJ determined by far-UV CD spectroscopy in the presence of 10-mM CaCl(2) was lower than that of Tk-S359A by 29.4 degrees C. The T(m) value of Tk-S359A was decreased by 29.5 degrees C by the treatment with 10 mM ethylenediaminetetraacetic acid, indicating that the beta-jelly roll domain contributes to the stabilization of Tk-S359A only in a Ca(2+)-bound form. Tk-SP highly resembles subtilisin-like serine proteases from Pyrococcus furiosus, Thermococcus gammatolerans, and Thermococcus onnurineus in size and amino acid sequence. We propose that attachment of a beta-jelly roll domain to the C-terminus is one of the strategies of the proteins from hyperthermophiles to adapt to high-temperature environment.
Crystal structure of a subtilisin homologue, Tk-SP, from Thermococcus kodakaraensis: requirement of a C-terminal beta-jelly roll domain for hyperstability.,Foophow T, Tanaka S, Angkawidjaja C, Koga Y, Takano K, Kanaya S J Mol Biol. 2010 Jul 23;400(4):865-77. Epub 2010 Jun 1. PMID:20595040[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
↑Foophow T, Tanaka S, Angkawidjaja C, Koga Y, Takano K, Kanaya S. Crystal structure of a subtilisin homologue, Tk-SP, from Thermococcus kodakaraensis: requirement of a C-terminal beta-jelly roll domain for hyperstability. J Mol Biol. 2010 Jul 23;400(4):865-77. Epub 2010 Jun 1. PMID:20595040 doi:10.1016/j.jmb.2010.05.064
