3BX1

Complex between the Barley alpha-Amylase/Subtilisin Inhibitor and the subtilisin Savinase

Summary for 3BX1

• Entry DOI: 10.2210/pdb3bx1/pdb
• Descriptor: Subtilisin Savinase, Alpha-amylase/subtilisin inhibitor, CALCIUM ION, ... (6 entities in total)
• Functional Keywords: complex (proteinase-inhibitor) enzyme inhibition, savinase, barley alpha-amylase/subtilisin inhibitor, calcium, hydrolase, metal-binding, protease, secreted, serine protease, sporulation, alpha-amylase inhibitor, protease inhibitor, serine protease inhibitor, hydrolase-hydrolase inhibitor complex, hydrolase/hydrolase inhibitor
• Biological source: Bacillus lentus; More
• Cellular location: Secreted: P29600
• Total number of polymer chains: 4
• Total formula weight: 94402.51

Authors

Micheelsen, P.O.,Vevodova, J.,Wilson, K.,Skjot, M. (deposition date: 2008-01-11, release date: 2008-07-08, Last modification date: 2024-10-30)

Primary citation

Micheelsen, P.O.,Vevodova, J.,De Maria, L.,Ostergaard, P.R.,Friis, E.P.,Wilson, K.,Skjot, M.
Structural and Mutational Analyses of the Interaction between the Barley alpha-Amylase/Subtilisin Inhibitor and the Subtilisin Savinase Reveal a Novel Mode of Inhibition
J.Mol.Biol., 380:681-690, 2008

PubMed Abstract: Subtilisins represent a large class of microbial serine proteases. To date, there are three-dimensional structures of proteinaceous inhibitors from three families in complex with subtilisins in the Protein Data Bank. All interact with subtilisin via an exposed loop covering six interacting residues. Here we present the crystal structure of the complex between the Bacillus lentus subtilisin Savinase and the barley alpha-amylase/subtilisin inhibitor (BASI). This is the first reported structure of a cereal Kunitz-P family inhibitor in complex with a subtilisin. Structural analysis revealed that BASI inhibits Savinase in a novel way, as the interacting loop is shorter than loops previously reported. Mutational analysis showed that Thr88 is crucial for the inhibition, as it stabilises the interacting loop through intramolecular interactions with the BASI backbone.

PubMed: 18556023
DOI: 10.1016/j.jmb.2008.05.034

Experimental method

X-RAY DIFFRACTION (1.85 Å)