Novel dimer structure of a membrane-bound protease with a catalytic Ser-Lys dyad and its linkage to stomatin
Yokoyama, H., Hamamatsu, S., Fujii, S., Matsui, I.(2008) J Synchrotron Radiat 15: 254-257
- PubMed: 18421152 
- DOI: https://doi.org/10.1107/S0909049507068471
- Primary Citation of Related Structures:  
3BPP - PubMed Abstract: 
Membrane-bound proteases are involved in various regulatory functions. A previous report indicates that the N-terminal region of PH1510 (1510-N) from the hyperthermophilic archaeon Pyrococcus horikoshii is a serine protease with a catalytic Ser-Lys dyad (Ser97 and Lys138), and specifically cleaves the C-terminal hydrophobic region of the p-stomatin PH1511. According to the crystal structure of the wild-type 1510-N in dimeric form, the active site around Ser97 is in a hydrophobic environment suitable for the hydrophobic substrates. This article reports the crystal structure of the K138A mutant of 1510-N at 2.3 A resolution. The determined structure contains one molecule per asymmetric unit, but 1510-N is active in dimeric form. Two possible sets of dimer were found from the symmetry-related molecules. One dimer is almost the same as the wild-type 1510-N. Another dimer is probably in an inactive form. The L2 loop, which is disordered in the wild-type structure, is significantly kinked at around A-138 in the K138A mutant. Thus Lys138 probably has an important role on the conformation of L2.
Organizational Affiliation: 
School of Pharmaceutical Sciences, University of Shizuoka, 52-1 Yada, Suruga-ku, Shizuoka 422-8526, Japan.