A Superb Biomining System for Heavy Metal Recovery
Abstract
Heavy metals are released to the environment from various industries, such as pharmaceuticals, pesticides, plastics, rubbers, tanneries, organic chemicals, wood products, and high technology industry, and from wars. They disrupt natural ecosystems and ultimately affect the health of humans and animals. Currently several strategies have been employed to remove heavy metal contaminants from polluted environments. The conventional methods, including precipitation, reverse osmosis, filtration, oxidation/reduction and membrane separation, are expensive and cannot remove heavy metals effectively. Moreover, the present recovery technology has strong environmental impacts and poor selectivity. To overcome these problems, a system of heavy metal binding proteins (e.g., metallothionein) will be constructed in a microbial host to recover cadmium (Cd), mercury (Hg) and other heavy metals from the contaminated sites. To develop a superb biomining complex, we will make use of the multiple-enzyme complex system known as ÒcellulosomeÓ from Clostridium thermocellum. A cellulosome consists of several subunits including a cell-surface anchor, scaffoldin proteins, and multiple enzymes. The high affinity cohesion-dockerin interaction of this cellulosome complex and its multiple binding domains will be the key factor for increasing the efficiency of the removal of heavy metals. The metal binding domains instead of enzymes will be fused with the dockerin domains via synthetic biology techniques and thus will interact with the cohesins of the scaffoldin protein (CipA). Then the entire complex will interact with the cohesins of an anchoring protein, which is anchored on the cell membrane of the host. By using this complex system 63 metal binding domains will be assembled in a cellulosome complex. It can be readily modified to recover rare metals from contaminating solids of mining sites or waste water of IC industry.documentation should be included by appendix to the proposal.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Feb 14, 2019
- Source ID
- W911NF1810188
Entities
People
- Wen-Hsiung Li
Organizations
- Academia Sinica
- Army Contracting Command
- United States Army