Publication Abstract from PubMed
Aspergilloglutamic peptidase from Aspergillus niger var. macrosporus (AGP) is one of the so-called pepstatin-insensitive acid endopeptidases, which are distinct from the well-studied aspartic peptidases. Among the known homologues of the glutamic peptidases, AGP is a unique two-chain enzyme with a light chain and a heavy chain bound non-covalently with each other, and thus is an interesting target for protein structure-function relationship studies. In this article, we report the crystal structure of a dimeric form of the enzyme at a resolution of 1.6 A. This form has a unique structure in which the C-terminal region of the light chain of one of the molecules binds to the active site cleft of the other molecule like a part of a substrate. This form mimics the enzyme-activation product complex produced upon autoproteolysis, and provides a structural clue that could help to clarify the activation mechanism. This type of dimeric structure of a peptidase is here reported for the first time.
The crystal structure of an intermediate dimer of aspergilloglutamic peptidase that mimics the enzyme-activation product complex produced upon autoproteolysis.,Sasaki H, Kubota K, Lee WC, Ohtsuka J, Kojima M, Iwata S, Nakagawa A, Takahashi K, Tanokura M J Biochem. 2012 Jul;152(1):45-52. Epub 2012 May 7. PMID:22569035[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.