Engineering the Primary Substrate Specificity of Streptomyces griseus Trypsin.Page, M.J., Wong, S.L., Hewitt, J., Strynadka, N.C., MacGillivray, R.T.
(2003) Biochemistry 42: 9060-9066
- PubMed: 12885239
- DOI: 10.1021/bi0344230
- Primary Citation of Related Structures:  1OSS
- PubMed Abstract:
- Critical Comparison of Comparative Model Building of Streptomyces Griseus Trypsin
Read, R.J.,Brayer, G.D.,Jurasek, L.,James, M.N.G.
(1984) Biochemistry 23: 6570
- Refined Crystal Structure of Streptomyces Griseus Trypsin at 1.7 Angstroms Resolution
Read, R.J.,James, M.N.G.
(1988) J.Mol.Biol. 200: 523
Streptomyces griseus trypsin (SGT) was chosen as a model scaffold for the development of serine proteases with enhanced substrate specificity. Recombinant SGT has been produced in a Bacillus subtilis expression system in a soluble active form and pur ...
Streptomyces griseus trypsin (SGT) was chosen as a model scaffold for the development of serine proteases with enhanced substrate specificity. Recombinant SGT has been produced in a Bacillus subtilis expression system in a soluble active form and purified to homogeneity. The recombinant and native proteases have nearly identical enzymatic properties and structures. Four SGT mutants with alterations in the S1 substrate binding pocket (T190A, T190P, T190S, and T190V) were also expressed. The T190P mutant demonstrated the largest shift to a preference for Arg versus Lys in the P1 site. This was shown by a minor reduction in catalytic activity toward an Arg-containing substrate (k(cat) reduction of 25%). The crystal structures of the recombinant SGT and the T190P mutant in a complex with the inhibitor benzamidine were obtained at high resolution (approximately 1.9 A). The increase in P1 specificity, achieved with minimal effect on the catalytic efficiency, demonstrates that the T190P mutant is an ideal candidate for the design of additional substrate specificity engineered into the S2 to S4 binding pockets.
Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada.