1OYV

Crystal structure of tomato inhibitor-II in a ternary complex with subtilisin Carlsberg

Summary for 1OYV

• Entry DOI: 10.2210/pdb1oyv/pdb
• Related: 1SCN 4SGB
• Descriptor: Subtilisin Carlsberg, Wound-induced proteinase inhibitor-II, CALCIUM ION, ... (4 entities in total)
• Functional Keywords: serine proteinase inhibitor, ternary complex, multidomain inhibitor, potato ii family, hydrolase
• Biological source: Bacillus licheniformis; More
• Cellular location: Secreted: P05119 P00780
• Total number of polymer chains: 3
• Total formula weight: 68160.89

Authors

Barrette-Ng, I.H.,Ng, K.K.,Cherney, M.M.,Pearce, G.,Ryan, C.A.,James, M.N. (deposition date: 2003-04-07, release date: 2003-07-15, Last modification date: 2024-10-30)

Primary citation

Barrette-Ng, I.H.,Ng, K.K.,Cherney, M.M.,Pearce, G.,Ryan, C.A.,James, M.N.
Structural basis of inhibition revealed by a 1:2 complex of the two-headed tomato inhibitor-II and subtilisin Carlsberg
J.Biol.Chem., 278:24062-24071, 2003

PubMed Abstract: Multidomain proteinase inhibitors play critical roles in the defense of plants against predation by a wide range of pests. Despite a wealth of structural information on proteinase-single domain inhibitor interactions, the structural basis of inhibition by multidomain proteinase inhibitors remains poorly understood. Here we report the 2.5-A resolution crystal structure of the two-headed tomato inhibitor-II (TI-II) in complex with two molecules of subtilisin Carlsberg; it reveals how a multidomain inhibitor from the Potato II family of proteinase inhibitors can bind to and simultaneously inhibit two enzyme molecules within a single ternary complex. The N terminus of TI-II initiates the folding of Domain I (Lys-1 to Cys-15 and Pro-84 to Met-123) and then completes Domain II (Ile-26 to Pro-74) before coming back to complete the rest of Domain I (Pro-84 to Met-123). The two domains of TI-II adopt a similar fold and are arranged in an extended configuration that presents two reactive site loops at the opposite ends of the inhibitor molecule. Each subtilisin molecule interacts with a reactive site loop of TI-II through the standard, canonical binding mode. Remarkably, a significant distortion of the active site of subtilisin is induced by the presence of phenylalanine in the P1 position of reactive site loop II of TI-II. The structure of the TI-II.(subtilisin)2 complex provides a molecular framework for understanding how multiple inhibitory domains in a single Potato II type proteinase inhibitor molecule from the Potato II family act to inhibit proteolytic enzymes.

PubMed: 12684499
DOI: 10.1074/jbc.M302020200

Experimental method

X-RAY DIFFRACTION (2.5 Å)