4AFQ

Human Chymase - Fynomer Complex

Summary for 4AFQ

• Entry DOI: 10.2210/pdb4afq/pdb
• Related: 1A0N 1AOT 1AOU 1AVZ 1AZG 1EFN 1FYN 1G83 1KLT 1M27 1NN6 1NYF 1NYG 1PJP 1SHF 1T31 1ZBJ 2DQ7 4AFS 4AFU 4AFZ
• Descriptor: CHYMASE, FYNOMER, CITRATE ANION, ... (5 entities in total)
• Functional Keywords: hydrolase-de novo protein complex, inhibitor, serine protease, hydrolase/de novo protein
• Biological source: HOMO SAPIENS; More
• Cellular location: Secreted: P23946
• Total number of polymer chains: 4
• Total formula weight: 70407.22

Authors

Schlatter, D.,Brack, S.,Banner, D.W.,Batey, S.,Benz, J.,Bertschinger, J.,Huber, W.,Joseph, C.,Rufer, A.,Van Der Kloosters, A.,Weber, M.,Grabulovski, D.,Hennig, M. (deposition date: 2012-01-23, release date: 2012-07-11, Last modification date: 2024-05-01)

Primary citation

Schlatter, D.,Brack, S.,Banner, D.W.,Batey, S.,Benz, J.,Bertschinger, J.,Huber, W.,Joseph, C.,Rufer, A.,Van Der Klooster, A.,Weber, M.,Grabulovski, D.,Hennig, M.
Generation, Characterization and Structural Data of Chymase Binding Proteins Based on the Human Fyn Kinase SH3 Domain.
Mabs, 4:497-, 2012

PubMed Abstract: The serine protease chymase (EC = 3.4.21.39) is expressed in the secretory granules of mast cells, which are important in allergic reactions. Fynomers, which are binding proteins derived from the Fyn SH3 domain, were generated against human chymase to produce binding partners to facilitate crystallization, structure determination and structure-based drug discovery, and to provide inhibitors of chymase for therapeutic applications. The best Fynomer was found to bind chymase with a KD of 0.9 nM and koff of 6.6x10 (-4) s (-1) , and to selectively inhibit chymase activity with an IC 50 value of 2 nM. Three different Fynomers were co-crystallized with chymase in 6 different crystal forms overall, with diffraction quality in the range of 2.25 to 1.4 Å resolution, which is suitable for drug design efforts. The X-ray structures show that all Fynomers bind to the active site of chymase. The conserved residues Arg15-Trp16-Thr17 in the RT-loop of the chymase binding Fynomers provide a tight interaction, with Trp16 pointing deep into the S1 pocket of chymase. These results confirm the suitability of Fynomers as research tools to facilitate protein crystallization, as well as for the development of assays to investigate the biological mechanism of targets. Finally, their highly specific inhibitory activity and favorable molecular properties support the use of Fynomers as potential therapeutic agents.

PubMed: 22653218
DOI: 10.4161/MABS.20452

Experimental method

X-RAY DIFFRACTION (1.51 Å)