A novel phospholipase A2/esterase from hyperthermophilic archaeon Aeropyrum pernix K1
Protein Expression and PuriWcation 35(2004)199-205，-0001，（）：
An open reading frame of the hyperthermophilic archaeon Aeropyrum pernix K1 APE2325, which composed of 474 bases, was cloned and expressed in Escherichia coli BL21 (DE3) Codon Plus-RIL. The recombinant protein was puriWed by Ni-chelation aYnity chromatography. It showed a single band with a molecular mass of 18kDa in SDS–PAGE. The puriWed enzyme exhibited both phospholipase A2 and esterase activities with the optimal catalytic temperature at 90℃. The enzyme activity was Ca2+-independent. Kinetic analysis revealed its Km, kcat, and Vm for the p-nitrophenyl propionate substrate were 103μM, 39s-1, and 249μmol/min/mg, respectively. The recombinant protein was thermostable and its half-life at 100℃ was about 1h.