1BFA

RECOMBINANT BIFUNCTIONAL HAGEMAN FACTOR/AMYLASE INHIBITOR FROM MAIZE

Summary for 1BFA

• Entry DOI: 10.2210/pdb1bfa/pdb
• Descriptor: BIFUNCTIONAL AMYLASE/SERINE PROTEASE INHIBITOR (2 entities in total)
• Functional Keywords: serine protease inhibitor, amylase/protease bifunctional inhibitor
• Biological source: Zea mays
• Cellular location: Secreted: P01088
• Total number of polymer chains: 1
• Total formula weight: 14363.73

Authors

Behnke, C.A.,Yee, V.C.,Le Trong, I.,Pedersen, L.C.,Stenkamp, R.E.,Kim, S.S.,Reeck, G.R.,Teller, D.C. (deposition date: 1998-05-13, release date: 1998-08-12, Last modification date: 2024-11-20)

Primary citation

Behnke, C.A.,Yee, V.C.,Trong, I.L.,Pedersen, L.C.,Stenkamp, R.E.,Kim, S.S.,Reeck, G.R.,Teller, D.C.
Structural determinants of the bifunctional corn Hageman factor inhibitor: x-ray crystal structure at 1.95 A resolution.
Biochemistry, 37:15277-15288, 1998

PubMed Abstract: Corn Hageman factor inhibitor (CHFI) is a bifunctional 127 residue, 13.6 kDa protein isolated from corn seeds. It inhibits mammalian trypsin and Factor XIIa (Hageman Factor) of the contact pathway of coagulation as well as alpha-amylases from several insect species. Among the plasma proteinases, CHFI specifically inhibits Factor XIIa without affecting the activity of other coagulation proteinases. We have isolated CHFI from corn and determined the crystallographic structure at 1.95 A resolution. Additionally, we have solved the structure of the recombinant protein produced in Escherichia coli at 2.2 A resolution. The two proteins are essentially identical. The proteinase binding loop is in the canonical conformation for proteinase inhibitors. In an effort to understand alpha-amylase inhibition by members of the family of 25 cereal trypsin/alpha-amylase inhibitors, we have made three-dimensional models of several proteins in the family based on the CHFI coordinates and the coordinates determined for wheat alpha-amylase inhibitor 0.19 [Oda, Y., Matsunaga, T., Fukuyama, K., Miyazaki, T., and Morimoto, T. (1997) Biochemistry 36, 13503-13511]. From an analysis of the models and a structure-based sequence analysis, we propose a testable hypothesis for the regions of these proteins which bind alpha-amylase. In the course of the investigations, we have found that the cereal trypsin/alpha-amylase inhibitor family is evolutionarily related to the family of nonspecific lipid-transfer proteins of plants. This is a new addition to the group which now consists of the trypsin/alpha-amylase inhibitors, 2S seed storage albumins, and the lipid-transfer family. Apparently, the four-helix conformation has been a successful vehicle in plant evolution for providing protection from predators, food for the embryo, and lipid transfer.

PubMed: 9799488
DOI: 10.1021/bi9812266

Experimental method

X-RAY DIFFRACTION (2.2 Å)