1. A Toxic Metal
“Sponge”
A Novel Technology For Water Remediation…
California State University, Long Beach
Phuc Nguyen
Acey Lab
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2015 ACS Southern California Undergraduate Research conference, UC San Diego

2. OUTLINE
The Problem
Metallothionein Overview
Experiments:
•Purification
•Metal Binding Properties
•Metal Recovery technology
Conclusion
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3. THE PROBLEM
Wastewater Containing
Toxic Metals
Lead | Mercury | Arsenic
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4. THE ANSWER: METALLOTHIONEIN (MT)
• Low Molecular Weight.
• Cysteine rich.
• Selectively Binds Toxic/Precious Metals
 Hg, Pb, As, U
 Au, Ag, Pt, Pd
• High Affinity: 4 x 10-14 M-1 for Pb
• Active At Extreme Conditions
 Temperature - 100oC
 pH - 4 to 10
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5. EXPRESSION AND PURIFICATION OF
RECOMBINANT MT
MT Gene Cloned into pET 11a
Recombinant MT Expressed in BL-21
E.coli
Sonication
G-50 Sephadex Gel Filtration
Mono Q Anion Exchange
Superdex Gel Filtration
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6. SDS-PAGE ANALYSIS OF PURIFIED MT
MT
6.5 KDa
Standards
26.6 KDa
16.9 KDa
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7. METAL BINDING ACTIVITY
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Free-metal
MT-bound metal

8. METAL BINDING ACTIVITY
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9. METAL BINDING IN ACETONE
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10. TECHNOLOGY FOR METAL REMOVAL
US Patent Number 7,273,962.
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11. METAL RECOVERY FROM SEA WATER
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585 CPM 109Cd
4,612 CPM 109Cd

12. CONCLUSION
•Recombinant MT is Expressed and
Purified
•MT binds a Number of Toxic/ Precious
Metals
•Active in 30% Acetone
•Metal Binding Effective In High Salt
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13. 13
Dr. Roger Acey
Dr. Katherine Kantardjieff
Paul Madera
Brent Wilkinson
Aaron Ong
Hieu Nguyen
ACKNOWLEDGEMENT