3fct
From Proteopedia
MATURE METAL CHELATASE CATALYTIC ANTIBODY WITH HAPTEN
Overview
A classic hypothesis for enzyme catalysis is the induction of strain in the substrate. This notion was first expressed by Haldane with the lock and key analogy-"the key does not fit the lock perfectly but exercises a certain strain on it" (1). This mechanism has often been invoked to explain the catalytic efficiency of enzymes but has been difficult to establish conclusively (2-7). Here we describe X-ray crystallographic and mutational studies of an antibody metal chelatase which strongly support the notion that this antibody catalyzes metal ion insertion into the porphyrin ring by inducing strain. Analysis of the germline precursor suggests that this strain mechanism arose during the process of affinity maturation in response to a conformationally distorted N-alkylmesoporphyrin.
About this Structure
Full crystallographic information is available from OCA.
Reference
Structural and kinetic evidence for strain in biological catalysis., Romesberg FE, Santarsiero BD, Spiller B, Yin J, Barnes D, Schultz PG, Stevens RC, Biochemistry. 1998 Oct 13;37(41):14404-9. PMID:9772166 Page seeded by OCA on Sun May 4 22:01:46 2008
