1t6e

Publication Abstract from PubMed

Plants developed a diverse battery of defense mechanisms in response to continual challenges by a broad spectrum of pathogenic microorganisms. Their defense arsenal includes inhibitors of cell wall-degrading enzymes, which hinder a possible invasion and colonization by antagonists. The structure of Triticum aestivum xylanase inhibitor-I (TAXI-I), a first member of potent TAXI-type inhibitors of fungal and bacterial family 11 xylanases, has been determined to 1.7-A resolution. Surprisingly, TAXI-I displays structural homology with the pepsin-like family of aspartic proteases but is proteolytically nonfunctional, because one or more residues of the essential catalytical triad are absent. The structure of the TAXI-I.Aspergillus niger xylanase I complex, at a resolution of 1.8 A, illustrates the ability of tight binding and inhibition with subnanomolar affinity and indicates the importance of the C-terminal end for the differences in xylanase specificity among different TAXI-type inhibitors.

Structural basis for inhibition of Aspergillus niger xylanase by triticum aestivum xylanase inhibitor-I.,Sansen S, De Ranter CJ, Gebruers K, Brijs K, Courtin CM, Delcour JA, Rabijns A J Biol Chem. 2004 Aug 20;279(34):36022-8. Epub 2004 May 27. PMID:15166216^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.