title: Cell surface display of synthetic phytochelatins using ice nucleation protein for enhanced heavy metal bioaccumulation.
abstract: Synthetic phytochelatins (ECs) composed of (Glu-Cys)nGly are protein analogs of phytochelatin that exhibit improved metal-binding capacity over metallothioneins (MTs). Expression of EC20 on the surface of E. coli using the Lpp-OmpA anchor resulted in improved bioaccumulation of cadmium and mercury, providing a new method for treating heavy metal contamination. To further improve the whole-cell accumulation of heavy metals, EC20 was expressed on the surface of Moraxella sp., a bacterium known to survive in contaminated environments, using the truncated ice nucleation protein (INPNC) anchor. Production of EC20 was approximately three-fold higher in Moraxella sp. than E. coli. As a consequence, the mercury-binding capacity of the recombinant Moraxella sp. was increased by more than 10-fold. Owing to the very high level of surface expression, the use of Moraxella sp. and INPNC anchor may prove to be useful for the remediation of other environmental contaminants.
authors.affiliation: Department of Chemical and Environmental Engineering, University of California, Riverside, CA 92521, USA.
authors.forename: Weon
authors.initials: W
authors.lastname: Bae
authors.forename: Ashok
authors.initials: A
authors.lastname: Mulchandani
authors.forename: Wilfred
authors.initials: W
authors.lastname: Chen
mesh_terms: D001425:Bacterial Outer Membrane Proteins / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism*; D001483:Base Sequence; D015153:Blotting, Western; D002462:Cell Membrane / Q000378:metabolism; D017931:DNA Primers; D004926:Escherichia coli / Q000378:metabolism; D005978:Glutathione; D008667:Metalloproteins / Q000378:metabolism*; D019216:Metals, Heavy / Q000378:metabolism*; D008856:Microscopy, Fluorescence; D009016:Moraxella / Q000235:genetics; D054811:Phytochelatins; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism
chemical_list: D001425:Bacterial Outer Membrane Proteins; D017931:DNA Primers; D008667:Metalloproteins; D019216:Metals, Heavy; D011994:Recombinant Proteins; C063113:ice nucleation protein; D054811:Phytochelatins; D005978:Glutathione