Effect of differential expression of pro-region on the transglutaminase productivity in pichia pastoris

Transglutaminase (TG) induces protein cross-linking by catalyzing the reaction of acyl transfer. Mature sequence of TG is inactive when express without its pro-region. Since pro-region is critical for inhibiting the TG's action and for correctly folding it extracellularly, the production is either poor or forming inclusion bodies without its pro-region. One of the fundamental steps for higher yield to date is to increase the transcriptional level of the recombinant gene by generating multicopies that could only be accomplished by cloning the concatemers. Here, co-expressing strain was successfully generated by incorporating pro-region into ribosomal DNA (rDNA) sites to achieve different copies. The maximum enzyme activity was up to 3.9u/ml compared to the wild type that was only 2.1u/ml in shake flasks being inducted for 96hrs.This research work provides an important strategy for its pro-region to take advantage of the degree of transglutaminase folding.