Structure Report for: 6AVX

Burger et al. show that Acyl-protein thioesterase structures present a long tunnel for accommodation of long-chain fatty acids and release the product by use of a flexible loop tunnel lid. Homologous deacetylases use a hydrophobic residue to fix the lid and another residue to close the tunnel entrance. This causes loop rigidity changing the catalytic preference to deacetylation. SOBER1 is a protein deacetylase and not an acylprotein thioesterase

Title: A hydrophobic anchor mechanism defines a deacetylase family that suppresses host response against YopJ effectors
Burger M, Willige BC, Chory J
Ref: Nat Commun, 8:2201, 2017 : PubMed
Abstract


ESTHER: Burger_2017_Nat.Commun_8_2201
PubMedSearch: Burger 2017 Nat.Commun 8 2201
PubMedID: 29259199
Gene_locus related to this paper: maize-b6t1C9, arath-SOBR1, arath-SOBRL, arath-AT5G20060

Abstract

Several Pseudomonas and Xanthomonas species are plant pathogens that infect the model organism Arabidopsis thaliana and important crops such as Brassica. Resistant plants contain the infection by rapid cell death of the infected area through the hypersensitive response (HR). A family of highly related alpha/beta hydrolases is involved in diverse processes in all domains of life. Functional details of their catalytic machinery, however, remained unclear. We report the crystal structures of alpha/beta hydrolases representing two different clades of the family, including the protein SOBER1, which suppresses AvrBsT-incited HR in Arabidopsis. Our results reveal a unique hydrophobic anchor mechanism that defines a previously unknown family of protein deacetylases. Furthermore, this study identifies a lid-loop as general feature for substrate turnover in acyl-protein thioesterases and the described family of deacetylases. Furthermore, we found that SOBER1's biological function is not restricted to Arabidopsis thaliana and not limited to suppress HR induced by AvrBsT.