2JTC

3D structure and backbone dynamics of SPE B

Summary for 2JTC

• Entry DOI: 10.2210/pdb2jtc/pdb
• Descriptor: Streptopain (1 entity in total)
• Functional Keywords: dynamics, loop movement, streptopain, hydrolase, protease, secreted, thiol protease, toxin, virulence, zymogen
• Biological source: Streptococcus pyogenes serotype M1
• Cellular location: Secreted: P0C0J1
• Total number of polymer chains: 1
• Total formula weight: 27565.44

Authors

Chuang, W.,Wang, C.,Houng, H.,Chen, C.,Wang, P. (deposition date: 2007-07-26, release date: 2008-08-26, Last modification date: 2024-05-29)

Primary citation

Wang, C.C.,Houng, H.C.,Chen, C.L.,Wang, P.J.,Kuo, C.F.,Lin, Y.S.,Wu, J.J.,Lin, M.T.,Liu, C.C.,Huang, W.,Chuang, W.J.
Solution structure and backbone dynamics of streptopain: insight into diverse substrate specificity.
J.Biol.Chem., 284:10957-10967, 2009

PubMed Abstract: Streptococcal pyrogenic exotoxin B (SPE B) is a cysteine protease expressed by Streptococcus pyogenes. The D9N, G163S, G163S/A172S, and G239D mutant proteins were expressed to study the effect of the allelic variants on their protease activity. In contrast to other mutants, the G239D mutant was approximately 12-fold less active. The Gly-239 residue is located within the C-terminal S230-G239 region, which cannot be observed in the x-ray structure. The three-dimensional structure and backbone dynamics of the 28-kDa mature SPE B (mSPE B) were determined. Unlike the x-ray structure of the 40-kDa zymogen SPE B (proSPE B), we observed the interactions between the C-terminal loop and the active site residues in mSPE B. The structural differences between mSPE B and proSPE B were the conformation of the C-terminal loop and the orientation of the catalytic His-195 residue, suggesting that activation and inactivation of SPE B is involved in the His-195 side-chain rotation. Dynamics analysis of mSPE B and the mSPE B/inhibitor complexes showed that the catalytic and C-terminal loops were the most flexible regions with low order parameter values of 0.5 to 0.8 and exhibited the motion on the ps/ns timescale. These findings suggest that the flexible C-terminal loop of SPE B may play an important role in controlling the substrate binding, resulting in its broad substrate specificity.

PubMed: 19237546
DOI: 10.1074/jbc.M807624200

Experimental method

SOLUTION NMR