PTCL1-EstA from Paenarthrobacter aurescens TC1, a Candidate for Industrial Application Belonging to the VIII Esterase Family

The esterase PTCL1-EstA from Paenarthrobacter aurescens TC1 was expressed in Escherichia coli and characterized. An 1152 bp open reading frame encoding a 383 amino acid polypeptide successfully expressed, the C-terminally His6-tagged enzyme purified, predicted molecular mass of purified 40.6 kDa. EstA family serine hydrolase belongs to VIII, contains esterase-labeled S-C-S-K sequences, homologous class C beta-lactamase sequences. favored p-nitrophenyl esters with C2-C6 chain lengths, but it also able hydrolyze long-chain esters. Homology modelling substrate docking that Ser59 an active site residue PTCL1-EstA, as well Tyr148, Ala325, Asp323, which are critical catalyzing enzymatic reaction reached highest specific activity against butyrate (C4) at pH 7.0 45 °C revealed better thermal stability 40 maintained high relative 5.0–9.0. Fermentation medium optimization for increased 510.76 U/mL, tapping potential industrial production.