The Corn Inhibitor of Blood Coagulation Factor XIIa

Pedersen, Lars C.; Yee, Vivien C.; Dassow, George von; Hazegh‐Azam, Maryam; Reeck, Gerald R.; Stenkamp, Ronald E.; Teller, David C.

doi:10.1006/jmbi.1994.1147

Cited by 5 publications

(2 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…(B) Crystal Growth. Crystals were grown using conditions similar to those described in Pedersen et al (19). Wildtype CHFI was dissolved in water to a concentration of 25 mg/mL and mixed with an equal volume of reservoir solution (30% PEG-400, 0.2M MgCl 2 , and 0.1 M Hepes at pH 7.5).…”

Section: Methodsmentioning

confidence: 99%

See 1 more Smart Citation

Structural Determinants of the Bifunctional Corn Hageman Factor Inhibitor: X-ray Crystal Structure at 1.95 Å Resolution^,

et al. 1998

Self Cite

View full text Add to dashboard Cite

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.

show abstract

Section: Methodsmentioning

confidence: 99%

“…Both 7n-CHFI and wt-CHFI crystallize with a ) b ) 57.12 Å and c ) 80.24 Å, space group P4 2 2 1 2. The ratio of molecular mass to unit cell volume ( 20) is 2.6 Da/Å 3 , which converts to 51% solvent content (19).…”

Section: Methodsmentioning

confidence: 99%

Structural Determinants of the Bifunctional Corn Hageman Factor Inhibitor: X-ray Crystal Structure at 1.95 Å Resolution^,

et al. 1998

Self Cite

View full text Add to dashboard Cite

show abstract

Dual surface modification with PEG and corn trypsin inhibitor: Effect of PEG:CTI ratio on protein resistance and anticoagulant properties

Alibeik

Zhu

Yau

et al. 2012

J Biomedical Materials Res

View full text Add to dashboard Cite

The objective of this study was to investigate the bioactivity and protein-resistant properties of dual functioning surfaces modified with PEG for protein resistance and corn trypsin inhibitor (CTI) for anticoagulant effect. Surfaces on gold substrate were prepared with varying ratios of free PEG to CTI-conjugated PEG. Two methods designated, respectively, "sequential" and "direct" were used. For sequential surfaces, PEG was first immobilized on gold and the surfaces were incubated with CTI at varying concentration. For direct surfaces, a PEG-CTI conjugate was synthesized and gold surfaces were modified using solutions of the conjugate of varying concentration. The CTI density on these surfaces was measured using radiolabeled CTI. Water contact angles were measured and the thickness of PEG-CTI layers was determined by ellipsometry. Fibrinogen adsorption from buffer and human plasma, and adsorption from binary solutions of fibrinogen and α-lactalbumin were investigated using radiolabeling methods. Bioactivity of the surfaces was evaluated via their effects on FXIIa inhibition and plasma clotting time. It was found that as the ratio of CTI-conjugated PEG to free PEG increased, bioactivity increased but protein resistance was relatively constant. It is concluded that on these surfaces conjugation of PEG to CTI does not greatly compromise the protein resistance of the PEG but results in improved interactions between the CTI and the "target" protein FXIIa. At the same CTI density, sequential surfaces were more effective in terms of inhibiting FXIIa and prolonging clotting time.

show abstract

The Corn Inhibitor of Activated Hageman Factor: Purification and Properties of Two Recombinant Forms of the Protein

Hazegh‐Azam

Kim

Masoud

et al. 1998

Protein Expression and Purification

View full text Add to dashboard Cite

The Corn Inhibitor of Blood Coagulation Factor XIIa

Cited by 5 publications

References 0 publications

Structural Determinants of the Bifunctional Corn Hageman Factor Inhibitor: X-ray Crystal Structure at 1.95 Å Resolution^,

Structural Determinants of the Bifunctional Corn Hageman Factor Inhibitor: X-ray Crystal Structure at 1.95 Å Resolution^,

Dual surface modification with PEG and corn trypsin inhibitor: Effect of PEG:CTI ratio on protein resistance and anticoagulant properties

The Corn Inhibitor of Activated Hageman Factor: Purification and Properties of Two Recombinant Forms of the Protein

Contact Info

Product

Resources

About

The Corn Inhibitor of Blood Coagulation Factor XIIa

Cited by 5 publications

References 0 publications

Structural Determinants of the Bifunctional Corn Hageman Factor Inhibitor: X-ray Crystal Structure at 1.95 Å Resolution,

Structural Determinants of the Bifunctional Corn Hageman Factor Inhibitor: X-ray Crystal Structure at 1.95 Å Resolution,

Dual surface modification with PEG and corn trypsin inhibitor: Effect of PEG:CTI ratio on protein resistance and anticoagulant properties

The Corn Inhibitor of Activated Hageman Factor: Purification and Properties of Two Recombinant Forms of the Protein

Contact Info

Product

Resources

About

Structural Determinants of the Bifunctional Corn Hageman Factor Inhibitor: X-ray Crystal Structure at 1.95 Å Resolution^,

Structural Determinants of the Bifunctional Corn Hageman Factor Inhibitor: X-ray Crystal Structure at 1.95 Å Resolution^,