Expression pattern of recombinant organophosphorus hydrolase from Flavobacterium sp. ATCC 27551 in Escherichia coli

Concerned with the influence of tagging system on the expression of heterogeneous protein in Escherichia coli, we attempted to express the organophosphorus hydrolase (OPH) of Flavobacterium sp. ATCC 27551 in E. coli. Recombinant OPH was overproduced successfully in E. coli when modified without the use of a tobacco etch virus (TEV) protease cleavage sequence. In addition, though there has never been a report on the extracellular secretion of recombinant OPH harboring native Tat signal peptides in E. coli, the produced protein was observed to be secreted extracellularly. Through the use of reverse transcriptional quantitative real-time PCR and comparison of the predicted folding rate, it was determined that OPH expression may be affected by the existence of a TEV protease cleavage sequence at the C-terminus during the process of translated protein folding, leading to the suppressed OPH activity. With the potential compatibility between native Tat signal peptides of OPH and E. coli Tat pathway secretion system, we report a successful expression of recombinant OPH harboring native Tat signal peptides in E. coli, for the first time.