1. Tianjin Key Laboratory for Modern Drug Delivery & High-Efficiency Collaborative Innovation Center of Chemical Science and Engineering School of Pharmaceutical Science and Technology Tianjin University Tianjin 300072 P. R. China
2. Frontiers Science Center for Synthetic Biology (Ministry of Education) Tianjin University Tianjin 300072 P. R. China
3. Singapore Institute of Food and Biotechnology Innovation Agency for Science, Technology and Research (A*STAR) 31 Biopolis Way Nanos #01-01, Singapore 138669 Singapore
4. Department of Chemical and Biomolecular Engineering University of Illinois at Urbana-Champaign 600 South Mathews Avenue Urbana, Illinois 61801 USA