Research Interests
Metabolic Engineering, Synthetic biology, Microbial Co-culture Engineering, Biosensing
Applied Microbiology, Natural Product Biosynthesis

Research Overview
     Our research aims at developing robust biological systems for high-efficiency biosynthesis of various value-added compounds, including commodity chemicals, specialty chemicals, nutraceuticals, cosmetics, and pharmaceuticals.

Bioproduction of commodity chemicals

     Our group is dedicated to creating novel engineering tools and methods for construction of robust microbial strains which are able to efficiently produce molecules with high industrial values. To this end, we engineer microorganism's genetic and metabolic setup in order to create desired microbial factories to generate the target products. In particular, our study focuses on converting renewable feed stocks, such as sugars and glycerol, to make the desired products. Metabolic engineering and process engineering approaches are employed to establish and optimize the production process to achieve high titers, productivities and yields.

Biosynthesis of complex compounds

     The emerging technologies and approaches in bioengineering offer unprecedented opportunities to modify and engineer microbes in order to suit the needs of biosynthesis of complex molecules with various biological values and applications. Our research utilizes current advancement in bioengineering and biotechnology to explore the potential of engineered microbial biosynthesis system. In  particular, we are interested in building novel biosynthesis pathways leading to formation of new nutraceutical and pharmaceutical molecules or optimizing the identified pathways for improving the biosynthesis performance. In addition, the microbial co-culture engineering strategies (see below) are utilized for construction of platform biocatalytic systems that consolidate the biosynthetic power of different microbial strains for the purpose of making compounds hard to biosynthesize by traditional methods. Our approach provides a new perspective to pursue discovery of novel pharmaceutical molecules, such as antibiotics, and re-programming of the existing biosynthetic routes that suffer from sub-optimal bioproduction performance.

Microbial co-culture engineering

     In addition to making specific products, we are also interesed in developing novel methodologies and platform technqiues that are generally applicable for biosynthesis of a wide range of bioproducts. Specifically, we study how to use a consortium of separate microbial cells (co-culture), rather than one sinlge cell (monoculture) to accommodate complicated biosynthetic pathways. Such a modularization of biosynthetic task between multiple strains offers several important advantages, such as metabolic burden reduction, increased cellular enviroment diversity for enzyme activity optimization, minimization of undesired cross-talk between different pathway modules, flexible balancing between upstream and downstream biosynthetic strength. Metabolic engineering and process engineering approaches are utilized to ensure the stability of robustness of the engineered co-culture systems. We have developed the microbial co-cultures that signficantly improved the bioproduction performance for a variety of biochemicals with varying chemical structures and properties. Efforts are being made towards applying the microbial co-culture engineering  strategies for efficient biosynthesis of highly complex and yet highly valuable compounds such as nutraceuticals and pharmaceuticals.      


     Metabolite biosensors are functional proteins, RNA or other biomolecules that can recognize specific metabolites and accordingly regulate metabolic activities such as gene expression. We study how to design and construct biosensor-based metabolic regulation systems in selected microbes. Such systems are able to self-tune key genes' expression according to target biomolecules' concentration change. As a result of the dynamic sensing and regulation, the metabolic resources can be rationally allocated to satisfy the need of both central metabolism and the biosynthetic pathway of target products. Subsequetnly, we can achieve the balance between cell growth and product formation for biosynthesis optimization. To this end, we explore innovative engineering strategies to maximize the biosensing and regulation capbilities in the selected micorbial hosts to serve the need of microbial bioproduction.

 Copyright 2021 the Zhang Lab
Chemical and Biochemical Engineering DepartmentSchool of EngineeringRutgers University