From the fungus Aspergillus niger, we identified a new gene encoding protein EstA, a member of the alpha/beta-hydrolase fold superfamily but of unknown substrate specificity. EstA was overexpressed and its crystal structure was solved by molecular replacement using a lipaseacetylcholinesterase chimera template. The 2.1 A resolution structure of EstA reveals a canonical Ser/Glu/ His catalytic triad located in a small pocket at the bottom of a large solvent-accessible, bowl-shaped cavity. Potential substrates selected by manual docking procedures were assayed for EstA activity. Consistent with the pocket geometry, preference for hydrolysis of short acyl/propyl chain substrates was found. Identification of close homologs from the genome of other fungi, of which some are broad host-range pathogens, defines EstA as the first member of a novel class of fungal esterases within the superfamily. Hence the structure of EstA constitutes a lead template in the design of new antifungal agents directed toward its pathogenic homologs.
- transcriptional activator xlnr
- 3-dimensional structure
- acetylxylan esterase
- antifungal agents
- vinyl esters
Bourne, Y., Hasper, A. A., Chahinian, H., Juin, M., & de Graaff, L. H. (2004). Aspergillus niger protein estA defines a new class of fungal esterases within the alfa/beta hydrolase fold superfamily of proteins. Structure, 12(8), 677-687. https://doi.org/10.1016/j.str.2004.03.005