Crystallization and structure elucidation of GDSL esterase of Photobacterium sp. J15

• Main Authors: Syed Mazlan, Sharifah Nur Hidayah, Mohamad Ali, Mohd Shukuri, Raja Abdul Rahman, Raja Noor Zaliha, Sabri, Suriana, Jonet, Mohd Anuar, Leow, Adam Thean Chor
• Format: Article
• Language: English
• Published: Elsevier 2018
• Online Access: http://psasir.upm.edu.my/id/eprint/72151/1/Crystallization%20and%20structure%20elucidation%20of%20GDSL%20esterase%20of%20Photobacterium%20sp.%20J15.pdf; http://psasir.upm.edu.my/id/eprint/72151/; https://www.sciencedirect.com/science/article/pii/S014181301832840X

GDSL esterase J15 (EstJ15) is a member of Family II of lipolytic enzyme. The enzyme was further classified in subgroup SGNH hydrolase due to the presence of highly conserve motif, Ser-Gly-Asn-His in four conserved blocks I, II, III, and V, respectively. X-ray quality crystal of EstJ15 was obtained from optimized formulation containing 0.10 M ammonium sulphate, 0.15 M sodium cacodylate trihydrate pH 6.5, and 20% PEG 8000. The crystal structure of EstJ15 was solved at 1.38 Å with one molecule per asymmetric unit. The structure exhibits α/β hydrolase fold and shared low amino acid sequence identity of 23% with the passenger domain of the autotransporter EstA of Pseudomonas aeruginosa. The active site is located at the centre of the structure, formed a narrow tunnel that hinder long substrates to be catalysed which was proven by the protein-ligand docking analysis. This study facilitates the understanding of high substrate specificity of EstJ15 and provide insights on its catalytic mechanism.