Wilfred Chen
Professor,
Chemical and Environmental Engineering
Environmental Engineering
Professor Wilfred Chen received his B.S. Degree in Chemical Engineering from the University of California, Los Angeles in 1988, and his Ph.D. degree in Chemical Engineering from The California Institute of Technology in 1993. He also spent one year as a postdoctoral research associate at the Institute of Biotechnology, Swiss Federal Institute of Technology, Zurich, Switzerland.
RESEARCH TOPICS
Over the past three decades breakthroughs in molecular genetics have revolutionized our ability to analyze and manipulate the structures and properties of nucleic acids and proteins. The combination of chemical engineering principles and molecular biology will be the foundation of an increasing number of problems, ranging from environmental monitoring and cleanup to the production of high value products. My current research efforts are focused on the development of novel biocatalysts and biological materials that can be used to enhance or manipulate microbial metabolism for the degradation of toxic pollutants or for environmentally-friendly chemical synthesis. Another area of interest is the application of these novel biocatalysts or biomaterials for biosensor development.
Environmental Biotechnology
One area of interest is the detoxification of organophosphate nerve agents. Organophosphorus hydrolase (OPH), an enzyme that hydrolyzes organophos-phates efficiently, was used to develop several microbial- and enzyme-based detoxification strategies. These strategies are suitable for development of low cost detoxification processes for the degradation of stored or spilled organophosphate wastes.
The second area of interest is the remediation of heavy metal contamination. Both microbial- and biopolymer-based technologies were developed. Synthetic phytochelatins (Glu-Cys)nGly (ECs) are cysteine-rich peptides that bind metal ions and sequester them in biological inactive forms. We demonstrated that E. coli with ECs anchored on the cell surface accumulated up to 30 fold more cadmium than wild-type cells. In parallel, tunable biopolymers with metal-binding properties were generated for heavy metal removal. By tuning the process temperature, reversible network formation between the individual biopolymer enables the recovery of sequestered metals by precipitation.
Biosensor
Biosensors are analytical tools or systems consisting of an immobilized biological sensing material in close contact with a suitable transducer that converts the biochemical signal to a quantifiable electrical signal.
Presently on-going projects are: (1) development of enzyme and microbial biosensors for selective, rapid and direct monitoring of organophosphate pesticides and nerve agents; and (2) development of novel molecular beacon-based DNA-probes for monitoring pathogens and viruses in drinking water.
HONORS
Participant in the National Academy of Engineering’s Fourth Annual Symposium on Frontiers of Engineering
NASA Certificate of Recognition
NSF Career Award
LAB FACILITIES
Our laboratory is equipped with the following equipment for the storage, study and characterization of protein, DNA and cells: incubator-shakers, refrigerators, a -20°C freezer, incubators, digital balances, a 2.5 1 fermentor with pH, DO, temperature, agitation and gas feed controls, gel electrophoresis equipment, western blotting equipment, photodocumentation equipment, water baths, microcentrifuges, and a refrigerated water bath. Additional equipment such as scintillation counters and ultracentrifuges are available in nearby departments.
RECENT PUBLICATIONS
Bae, W., Chen, W., Mulchandani, A. and Mehra, R. 2000. “Enhanced Bioaccumulation of Heavy Metal by Bacteria Cells Displaying Synthetic Phytochelatins,” Biotechnol. Bioeng. 70: 518-524.
Richins, R.D., Mulchandani, A. and Chen, W. 2000. “Expression, Immobilization, and Enzymatic Characterization of Cellulose-Binding Domain-Organophosphorus Hydrolase Fusion Proteins,” Biotechnol. Bioeng. 69: 591-596.
Chen, W., Martinez, G. and Mulchandani, A. 2000. “Molecular Beacons: A Real-Time PCR Assay for Detecting Salmonella,” Anal. Biochem. 280: 166-172.
Mulchandani, A., Mulchandani, P., Chen, W., Wang, J. and Chen, L. 1999. “Amperometric Thick-film Strip Electrodes for Monitoring Organophosphate Nerve Agents Based on Immobilized Organophosphorus Hydrolase,” Anal. Chem. 71: 2246-2249.
Chen, W., Bruhlmann, F., Richins, R.D. and Mulchandani, A. 1999. “Engineering of Improved Enzymes and Microbes for Bioremediation,” Curr. Opin. Biotechnol. 10: 137-141.
Bruhlmann, F. and Chen, W. 1999. “Tuning Biphenyl Dioxygenase for Extended Substrate Specificity,” Biotechnol. Bioeng. 63: 544-551.
Richins, R., Kaneva, I., Mulchandani, A. and Chen, W. 1997. “Biodegradation of Organophosphorus Pesticides by Surface-expressed Organophosphorus Hydrolase,” Nat. Biotechnol. 15: 984-987.
WWW: Research
Email: wilfred@engr.ucr.edu
Extension: 2473
Professor,
Chemical and Environmental Engineering
Environmental Engineering
Professor Wilfred Chen received his B.S. Degree in Chemical Engineering from the University of California, Los Angeles in 1988, and his Ph.D. degree in Chemical Engineering from The California Institute of Technology in 1993. He also spent one year as a postdoctoral research associate at the Institute of Biotechnology, Swiss Federal Institute of Technology, Zurich, Switzerland.
RESEARCH TOPICS
Over the past three decades breakthroughs in molecular genetics have revolutionized our ability to analyze and manipulate the structures and properties of nucleic acids and proteins. The combination of chemical engineering principles and molecular biology will be the foundation of an increasing number of problems, ranging from environmental monitoring and cleanup to the production of high value products. My current research efforts are focused on the development of novel biocatalysts and biological materials that can be used to enhance or manipulate microbial metabolism for the degradation of toxic pollutants or for environmentally-friendly chemical synthesis. Another area of interest is the application of these novel biocatalysts or biomaterials for biosensor development.
Environmental Biotechnology
One area of interest is the detoxification of organophosphate nerve agents. Organophosphorus hydrolase (OPH), an enzyme that hydrolyzes organophos-phates efficiently, was used to develop several microbial- and enzyme-based detoxification strategies. These strategies are suitable for development of low cost detoxification processes for the degradation of stored or spilled organophosphate wastes.
The second area of interest is the remediation of heavy metal contamination. Both microbial- and biopolymer-based technologies were developed. Synthetic phytochelatins (Glu-Cys)nGly (ECs) are cysteine-rich peptides that bind metal ions and sequester them in biological inactive forms. We demonstrated that E. coli with ECs anchored on the cell surface accumulated up to 30 fold more cadmium than wild-type cells. In parallel, tunable biopolymers with metal-binding properties were generated for heavy metal removal. By tuning the process temperature, reversible network formation between the individual biopolymer enables the recovery of sequestered metals by precipitation.
Biosensor
Biosensors are analytical tools or systems consisting of an immobilized biological sensing material in close contact with a suitable transducer that converts the biochemical signal to a quantifiable electrical signal.
Presently on-going projects are: (1) development of enzyme and microbial biosensors for selective, rapid and direct monitoring of organophosphate pesticides and nerve agents; and (2) development of novel molecular beacon-based DNA-probes for monitoring pathogens and viruses in drinking water.
HONORS
Participant in the National Academy of Engineering’s Fourth Annual Symposium on Frontiers of Engineering
NASA Certificate of Recognition
NSF Career Award
LAB FACILITIES
Our laboratory is equipped with the following equipment for the storage, study and characterization of protein, DNA and cells: incubator-shakers, refrigerators, a -20°C freezer, incubators, digital balances, a 2.5 1 fermentor with pH, DO, temperature, agitation and gas feed controls, gel electrophoresis equipment, western blotting equipment, photodocumentation equipment, water baths, microcentrifuges, and a refrigerated water bath. Additional equipment such as scintillation counters and ultracentrifuges are available in nearby departments.
RECENT PUBLICATIONS
Bae, W., Chen, W., Mulchandani, A. and Mehra, R. 2000. “Enhanced Bioaccumulation of Heavy Metal by Bacteria Cells Displaying Synthetic Phytochelatins,” Biotechnol. Bioeng. 70: 518-524.
Richins, R.D., Mulchandani, A. and Chen, W. 2000. “Expression, Immobilization, and Enzymatic Characterization of Cellulose-Binding Domain-Organophosphorus Hydrolase Fusion Proteins,” Biotechnol. Bioeng. 69: 591-596.
Chen, W., Martinez, G. and Mulchandani, A. 2000. “Molecular Beacons: A Real-Time PCR Assay for Detecting Salmonella,” Anal. Biochem. 280: 166-172.
Mulchandani, A., Mulchandani, P., Chen, W., Wang, J. and Chen, L. 1999. “Amperometric Thick-film Strip Electrodes for Monitoring Organophosphate Nerve Agents Based on Immobilized Organophosphorus Hydrolase,” Anal. Chem. 71: 2246-2249.
Chen, W., Bruhlmann, F., Richins, R.D. and Mulchandani, A. 1999. “Engineering of Improved Enzymes and Microbes for Bioremediation,” Curr. Opin. Biotechnol. 10: 137-141.
Bruhlmann, F. and Chen, W. 1999. “Tuning Biphenyl Dioxygenase for Extended Substrate Specificity,” Biotechnol. Bioeng. 63: 544-551.
Richins, R., Kaneva, I., Mulchandani, A. and Chen, W. 1997. “Biodegradation of Organophosphorus Pesticides by Surface-expressed Organophosphorus Hydrolase,” Nat. Biotechnol. 15: 984-987.
WWW: Research
Email: wilfred@engr.ucr.edu
Extension: 2473