AUTHOR=Sun Zhongke , Yue Zonghao , Yang Xingdong , Hao Xinqi , Song Maoping , Li Lili , Chen Can , Chu Cuiwei , Li Chengwei 

TITLE=Efficient Phytase Secretion and Phytate Degradation by Recombinant Bifidobacterium longum JCM 1217

JOURNAL=Frontiers in Microbiology

VOLUME=10

YEAR=2019

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2019.00796

DOI=10.3389/fmicb.2019.00796

ISSN=1664-302X

ABSTRACT=<p>Genetic engineering of probiotics, like bifidobacteria, may improve their microbial cell factory economy. This work designed a novel shuttle plasmid pBPES, which bears exogenous <italic>appA</italic> and is stable within <italic>Bifidobacterium longum</italic> JCM 1217. Cloning of three predicted promoters into pBPES proved that all of them drive appA expression in <italic>B. longum</italic> JCM 1217. Transformation of plasmids pBPES-tu and pBPES-groEL into <italic>B. longum</italic> JCM1217 resulted in much more phytase secretion suggests P<italic><sub>tu</sub></italic> and P<italic><sub>groEL</sub></italic> are strong promoters. Further <italic>in vitro</italic> and <italic>in vivo</italic> experiments suggested <italic>B. longum</italic> JCM 1217/pBPES-tu degrades phytate efficiently. In conclusion, the study screened two stronger promoters and constructed a recombinant live probiotic strain for effectively phytase secretion and phytate degradation in gut. The strategy used in the study provided a novel technique for improving the bioaccessibility of phytate and decreasing phosphorus excretion.</p>