4jgg
From Proteopedia
Crystal Structure of TesA
Structural highlights
FunctionEST_PSEAE Esterase that exhibits the highest activity towards Tween detergents and p-nitrophenyl esters of short acyl chain length. Also displays a low thioesterase activity towards palmitoyl-coenzyme A, but is not active towards acetyl-coenzyme A. Publication Abstract from PubMedTesA from Pseudomonas aeruginosa belongs to the GDSL hydrolase family of serine esterases and lipases that possess a broad substrate- and regiospecificity. It shows high sequence homology to TAP, a multifunctional enzyme from Escherichia coli exhibiting thioesterase, lysophospholipase A, protease and arylesterase activities. Recently, we demonstrated high arylesterase activity for TesA, but only minor thioesterase and no protease activity. Here, we present a comparative analysis of TesA and TAP at the structural, biochemical and physiological levels. The crystal structure of TesA was determined at 1.9 A and structural differences were identified, providing a possible explanation for the differences in substrate specificities. The comparison of TesA with other GDSL-hydrolase structures revealed that the flexibility of active-site loops significantly affects their substrate specificity. This assumption was tested using a rational approach: we have engineered the putative coenzyme A thioester binding site of E. coli TAP into TesA of P. aeruginosa by introducing mutations D17S and L162R. This TesA variant showed increased thioesterase activity comparable to that of TAP. TesA is the first lysophospholipase A described for the opportunistic human pathogen P. aeruginosa. The enzyme is localized in the periplasm and may exert important functions in the homeostasis of phospholipids or detoxification of lysophospholipids. Structural and Functional Characterisation of TesA - A Novel Lysophospholipase A from Pseudomonas aeruginosa.,Kovacic F, Granzin J, Wilhelm S, Kojic-Prodic B, Batra-Safferling R, Jaeger KE PLoS One. 2013 Jul 18;8(7):e69125. doi: 10.1371/journal.pone.0069125. Print 2013. PMID:23874889[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
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