Identification and characterization of an acetyl esterase from Paenibacillus sp. XW-6-66 and its novel function in 7-aminocephalosporanic acid deacetylation

ObjectivesTo obtain a new acetyl esterase from Paenibacillus sp. XW-6-66 and apply the enzyme to 7-aminocephalosporanic acid (7-ACA) deacetylation.ResultsThe acetyl esterase AesZY was identified from Paenibacillus sp. XW-6-66, and its enzymatic properties were investigated. With the putative catalytic triad Ser114-Asp203-His235, AesZY belongs to the Acetyl esterase (Aes) family which is included in the alpha/beta hydrolase superfamily and contains the consensus Gly-X-Ser-X-Gly motif. The maximum activity of AesZY was detected at pH 8.0 and 40 degrees C. AesZY was stable at different pH values ranging from 5.0 to 12.0, and was tolerant to several metal ions. Furthermore, the deacetylation activity of AesZY toward 7-ACA was approximately 7.5U/mg, and the K-cat/K-m value was 2.04s(-1)mM(-1).ConclusionsOur results demonstrate the characterization of a new acetyl esterase belonging to the Aes family with potential biotechnological applications.