MG53 is a double-edged sword for human diseases.

Mitsugumin 53 (MG53), also named Trim72, is a multi-functional TRIM-family protein, which is abundantly expressed in cardiac and skeletal muscle. It has been shown that MG53 not only plays important physiological roles but also acts as a crucial pathogenic factor of various diseases. First, MG53 preserves cardiac and skeletal muscle integrity via facilitating plasma membrane repair. Second, MG53 is essentially involved in cardiac ischemic preconditioning and postconditioning by activating PI3K-Akt-GSK3ß and ERK1/2 cell survival signaling pathways. Moreover, systemic delivery of recombinant MG53 is able to abolish mechanic or ischemia-reperfusion (I/R)-induced injury of multiple organs, including heart, skeletal muscle, lung, kidney and skin. Importantly, MG53 acts as an E3 ligase to mediate the degradation of insulin receptor and insulin receptor substrate-1, and subsequently induces insulin resistance and metabolic diseases such as type-2 diabetes and its cardiovascular complications. In addition, MG53 negatively regulates myogenesis. As a potential therapeutic target of human diseases, multiple facets of MG53 biological function and mechanisms of action should be taken into the consideration to maximize its beneficial effects and minimize potential side-effects. Here in this review, we intend to comprehensively summarize the current progresses on the biological functions of MG53, focusing on its clinical value as a therapeutic target.

Bioengineering of the Enterobacter aerogenes strain for biohydrogen production.

Enterobacter aerogenes is one of the most widely-studied model strains for fermentative hydrogen production. To improve the hydrogen yield of E. aerogenes, the bioengineering on a biomolecular level and metabolic network level is of importance. In this review, the fermentative technology of E. aerogenes for hydrogen production will be first briefly summarized. And then the bioengineering of E. aerogenes for the improvement of hydrogen yield will be thoroughly reviewed, including the anaerobic metabolic networks for hydrogen evolution in E. aerogenes, metabolic engineering for improving hydrogen production in E. aerogenes and mixed culture of E. aerogenes with other hydrogen-producing bacteria to enhance the overall yield in anaerobic cultivation. Finally, a perspective on E. aerogenes as a hydrogen producer including systems bioengineering approach for improving the hydrogen yield and application of the engineered E. aerogenes in mixed culture will be presented.