Phospholipase A2 (PLA2) from Streptomyces violaceoruber is a lipolytic enzyme used in a wide range of industrial applications including production of lysolecithins and enzymatic degumming of edible oils. We have therefore investigated expression and secretion of PLA2 in two workhorse microbes, Pichia pastoris and Escherichia coli. The PLA2 was produced to an activity of 0.517 ± 0.012 U/ml in the culture broth of the recombinant P. pastoris. On the other hand, recombinant E. coli BL21 star (DE3), overexpressing the authentic PLA2 (P-PLA2), showed activity of 17.0 ± 1.3 U/ml in the intracellular fraction and 21.7 ± 0.7 U/ml in the culture broth. The extracellular PLA2 activity obtained with the recombinant E. coli system was 3.2-fold higher than the corresponding value reached in a previous study, which employed recombinant E. coli BL21 (DE3) overexpressing codon-optimized PLA2. Finally, we observed that the extracellular PLA2 from the recombinant E. coli P-PLA2 culture was able to hydrolyze 31.1 g/l of crude soybean lecithin, an industrial substrate, to a conversion yield of approximately 95%. The newly developed E. coli-based PLA2 expression system led to extracellular production of PLA2 to a productivity of 678 U/l·h, corresponding to 157-fold higher than that obtained with the P. pastoris-based system.
Bibliographical noteFunding Information:
This research was financially supported by the National Research Foundation of Korea (NRF) Grant (2019R1C1C1003521) funded by the Korean Ministry of Science, ICT and Future Planning, and also by the Chung-Ang University Graduate Research Scholarship in 2019. Ara Cho, Yeji Hwang, and Jin-Byung Park were supported by the Marine Biomaterials Research Center grant from the Marine Biotechnology Program [No. D11013214H480000100] funded by the Ministry of Oceans and Fisheries, Korea.
© 2020 by The Korean Society for Microbiology and Biotechnology
- Escherichia coli
- Extracellular production
- Phospholipase A
- Pichia pastoris