skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Evolutionary selection of enzymatically synthesized semiconductors from biomimetic mineralization vesicles

Abstract

The way nature evolves and sculpts materials using proteins inspires new approaches to materials engineering but is still not completely understood. Here, we present a cell-free synthetic biological platform to advance studies of biologically synthesized solid-state materials. This platform is capable of simultaneously exerting many of the hierarchical levels of control found in natural biomineralization, including genetic, chemical, spatial, structural, and morphological control, while supporting the evolutionary selection of new mineralizing proteins and the corresponding genetically encoded materials that they produce. DNA-directed protein expression and enzymatic mineralization occur on polystyrene microbeads in water-in-oil emulsions, yielding synthetic surrogates of biomineralizing cells that are then screened by flow sorting, with light-scattering signals used to sort the resulting mineralized composites differentially. We demonstrate the utility of this platform by evolutionarily selecting newly identified silicateins, biomineralizing enzymes previously identified from the silica skeleton of a marine sponge, for enzyme variants capable of synthesizing silicon dioxide (silica) or titanium dioxide (titania) composites. Mineral composites of intermediate strength are preferentially selected to remain intact for identification during cell sorting, and then to collapse postsorting to expose the encoding genes for enzymatic DNA amplification. Some of the newly selected silicatein variants catalyze the formation of crystalline silicates,more » whereas the parent silicateins lack this ability. The demonstrated bioengineered route to previously undescribed materials introduces in vitro enzyme selection as a viable strategy for mimicking genetic evolution of materials as it occurs in nature.« less

Authors:
; ; ; ; ;  [1]
  1. (UCSB)
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States). Advanced Photon Source (APS)
Sponsoring Org.:
NSFUNIVERSITYDOE - BASIC ENERGY SCIENCES
OSTI Identifier:
1048951
Resource Type:
Journal Article
Journal Name:
Proc. Natl. Acad. Sci. USA
Additional Journal Information:
Journal Volume: 109; Journal Issue: (26) ; 06, 2012; Journal ID: ISSN 0027-8424
Country of Publication:
United States
Language:
ENGLISH
Subject:
59 BASIC BIOLOGICAL SCIENCES; 60 APPLIED LIFE SCIENCES; AMPLIFICATION; DNA; ENZYMES; GENES; GENETICS; IN VITRO; LIGHT SCATTERING; MINERALIZATION; OXIDES; POLYSTYRENE; PROTEINS; SILICA; SILICATES; SILICON; SKELETON; SORTING; TITANIUM

Citation Formats

Bawazer, Lukmaan A., Izumi, Michi, Kolodin, Dmitriy, Neilson, James R., Schwenzer, Birgit, and Morse, Daniel E. Evolutionary selection of enzymatically synthesized semiconductors from biomimetic mineralization vesicles. United States: N. p., 2012. Web. doi:10.1073/pnas.1116958109.
Bawazer, Lukmaan A., Izumi, Michi, Kolodin, Dmitriy, Neilson, James R., Schwenzer, Birgit, & Morse, Daniel E. Evolutionary selection of enzymatically synthesized semiconductors from biomimetic mineralization vesicles. United States. doi:10.1073/pnas.1116958109.
Bawazer, Lukmaan A., Izumi, Michi, Kolodin, Dmitriy, Neilson, James R., Schwenzer, Birgit, and Morse, Daniel E. Mon . "Evolutionary selection of enzymatically synthesized semiconductors from biomimetic mineralization vesicles". United States. doi:10.1073/pnas.1116958109.
@article{osti_1048951,
title = {Evolutionary selection of enzymatically synthesized semiconductors from biomimetic mineralization vesicles},
author = {Bawazer, Lukmaan A. and Izumi, Michi and Kolodin, Dmitriy and Neilson, James R. and Schwenzer, Birgit and Morse, Daniel E.},
abstractNote = {The way nature evolves and sculpts materials using proteins inspires new approaches to materials engineering but is still not completely understood. Here, we present a cell-free synthetic biological platform to advance studies of biologically synthesized solid-state materials. This platform is capable of simultaneously exerting many of the hierarchical levels of control found in natural biomineralization, including genetic, chemical, spatial, structural, and morphological control, while supporting the evolutionary selection of new mineralizing proteins and the corresponding genetically encoded materials that they produce. DNA-directed protein expression and enzymatic mineralization occur on polystyrene microbeads in water-in-oil emulsions, yielding synthetic surrogates of biomineralizing cells that are then screened by flow sorting, with light-scattering signals used to sort the resulting mineralized composites differentially. We demonstrate the utility of this platform by evolutionarily selecting newly identified silicateins, biomineralizing enzymes previously identified from the silica skeleton of a marine sponge, for enzyme variants capable of synthesizing silicon dioxide (silica) or titanium dioxide (titania) composites. Mineral composites of intermediate strength are preferentially selected to remain intact for identification during cell sorting, and then to collapse postsorting to expose the encoding genes for enzymatic DNA amplification. Some of the newly selected silicatein variants catalyze the formation of crystalline silicates, whereas the parent silicateins lack this ability. The demonstrated bioengineered route to previously undescribed materials introduces in vitro enzyme selection as a viable strategy for mimicking genetic evolution of materials as it occurs in nature.},
doi = {10.1073/pnas.1116958109},
journal = {Proc. Natl. Acad. Sci. USA},
issn = {0027-8424},
number = (26) ; 06, 2012,
volume = 109,
place = {United States},
year = {2012},
month = {10}
}