A engenharia de um conduíte elétron sintético em células vivas

segunda-feira, outubro 25, 2010


Engineering of a synthetic electron conduit in living cells

Heather M. Jensen a,b, Aaron E. Albers c, Konstantin R. Malley c,1, Yuri Y. Londer d, Bruce E. Cohen c, Brett A. Helms c, Peter Weigele d, Jay T. Groves a,b,c,e, and Caroline M. Ajo-Franklin b,c,2

-Author Affiliations

aDepartments of Chemistry and
eHoward Hughes Medical Institute, University of California, Berkeley, CA 94720;
bPhysical Biosciences and
cMaterials Sciences Divisions, Lawrence Berkeley National Laboratory, University of California, Berkeley, CA 94720; and
dNew England Biolabs, Ipswich, MA 01938

↵1Present address: Saint Louis University School of Medicine, St. Louis, MO 63104.

Edited by Charles R. Cantor, Sequenom, Inc., San Diego, CA, and approved September 8, 2010 (received for review July 2, 2010)

Abstract

Engineering efficient, directional electronic communication between living and nonliving systems has the potential to combine the unique characteristics of both materials for advanced biotechnological applications. However, the cell membrane is designed by nature to be an insulator, restricting the flow of charged species; therefore, introducing a biocompatible pathway for transferring electrons across the membrane without disrupting the cell is a significant challenge. Here we describe a genetic strategy to move intracellular electrons to an inorganic extracellular acceptor along a molecularly defined route. To do so, we reconstitute a portion of the extracellular electron transfer chain of Shewanella oneidensis MR-1 into the model microbe Escherichia coli. This engineered E. colican reduce metal ions and solid metal oxides ∼8× and ∼4× faster than its parental strain. We also find that metal oxide reduction is more efficient when the extracellular electron acceptor has nanoscale dimensions. This work demonstrates that a genetic cassette can create a conduit for electronic communication from living cells to inorganic materials, and it highlights the importance of matching the size scale of the protein donors to inorganic acceptors.

cytochrome c, nanobioelectronics, synthetic biology, iron reduction, living-nonliving interfaces

Footnotes

2To whom correspondence should be addressed. E-mail: cajo-franklin@lbl.gov.

Author contributions: H.M.J., Y.Y.L., P.W., J.T.G., and C.M.A.-F. designed research; H.M.J. and K.R.M. performed research; A.E.A., B.E.C., and B.A.H. contributed new reagents/analytic tools; H.M.J., Y.Y.L., P.W., and C.M.A.-F. analyzed data; and H.M.J. and C.M.A.-F. wrote the paper.

The authors declare no conflict of interest.

This article is a PNAS Direct Submission.

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