Featured Research

from universities, journals, and other organizations

Scientists synthesize first genetically evolved semiconductor material

Date:
June 13, 2012
Source:
University of California - Santa Barbara
Summary:
In the not-too-distant future, scientists may be able to use DNA to grow their own specialized materials, thanks to the concept of directed evolution. Scientists have, for the first time, used genetic engineering and molecular evolution to develop the enzymatic synthesis of a semiconductor.

This image shows the process of synthesizing silica through directed evolution of silicatein proteins.
Credit: Published with permission from PNAS Plus - Biological Sciences - Biochemistry: Lukmaan A. Bawazer, Michi Izumi, Dmitriy Kolodin, James R. Neilson, Birgit Schwenzer, and Daniel E. Morse PNAS Plus: Evolutionary selection of enzymatically synthesized semiconductors from biomimetic mineralization vesicles PNAS 2012 ; published ahead of print June 7, 2012, doi:10.1073/pnas.1116958109

In the not-too-distant future, scientists may be able to use DNA to grow their own specialized materials, thanks to the concept of directed evolution. UC Santa Barbara scientists have, for the first time, used genetic engineering and molecular evolution to develop the enzymatic synthesis of a semiconductor.

Related Articles


"In the realm of human technologies it would be a new method, but it's an ancient approach in nature," said Lukmaan Bawazer, first author of the paper, "Evolutionary selection of enzymatically synthesized semiconductors from biomimetic mineralization vesicles," published in the Proceedings of the National Academy of Sciences. Bawazer, who was a Ph.D. student at the time, wrote the paper with co-authors at UCSB's Interdepartmental Graduate Program in Biomolecular Science and Engineering; Institute for Collaborative Biotechnologies; California NanoSystems Institute and Materials Research Laboratory; and Department of Molecular, Cellular and Developmental Biology. Daniel Morse, UCSB professor emeritus of biochemistry of molecular genetics, directed the research.

Using silicateins, proteins responsible for the formation of silica skeletons in marine sponges, the researchers were able to generate new mineral architectures by directing the evolution of these enzymes. Silicateins, which are genetically encoded, serve as templates for the silica skeletons and control their mineralization, thus participating in similar types of processes by which animal and human bones are formed. Silica, also known as silicon, is the primary material in most commercially manufactured semiconductors.

In this study, polystyrene microbeads coated with specific silicateins were put through a mineralization reaction by incubating the beads in a water-in-oil emulsion that contained chemical precursors for mineralization: metals of either silicon or titanium dissolved in the oil or water phase of the emulsion. As the silicateins reacted with the dissolved metals, they precipitated them, integrating the metals into the resulting structure and forming nanoparticles of silicon dioxide or titanium dioxide.

With the creation of a silicatein gene pool, through what Bawazer only somewhat euphemistically calls "molecular sex" -- the combination and recombination of various silicatein genetic materials -- the scientists were able to create a multitude of silicateins, and then select for the ones with desired properties.

"This genetic population was exposed to two environmental pressures that shaped the selected minerals: The silicateins needed to make (that is, mineralize) materials directly on the surface of the beads, and then the mineral structures needed to be amenable to physical disruption to expose the encoding genes," said Bawazer. The beads that exhibited mineralization were sorted from the ones that didn't, and then fractured to release the genetic information they contained, which could either be studied, or evolved further.

The process yielded forms of silicatein not available in nature, that behaved differently in the formation of mineral structures. For example, some silicateins self-assembled into sheets and made dispersed mineral nanoparticles, as opposed to more typical agglomerated particles formed by natural silicateins. In some cases, crystalline materials were also formed, demonstrating a crystal-forming ability that was acquired through directed evolution, said Bawazer.

Because silicateins are enzymes, said Bawazer, with relatively long amino acid chains that can fold into precise shapes, there is the potential for more functionality than would be possible using shorter biopolymers or more traditional synthetic approaches. In addition, the process could potentially work with a variety of metals, to evolve different types of materials. By changing the laboratory-controlled environments in which directed evolution occurs, it will be possible to evolve materials with specific capacities, like high performance in an evolved solar cell, for example.

"Here we've demonstrated the evolution of material structure; I'd like to take it a step further and evolve material performance in a functional device," said Bawazer.

Research for this paper was supported by the U.S. Department of Energy.


Story Source:

The above story is based on materials provided by University of California - Santa Barbara. Note: Materials may be edited for content and length.


Journal Reference:

  1. L. A. Bawazer, M. Izumi, D. Kolodin, J. R. Neilson, B. Schwenzer, D. E. Morse. PNAS Plus: Evolutionary selection of enzymatically synthesized semiconductors from biomimetic mineralization vesicles. Proceedings of the National Academy of Sciences, 2012; DOI: 10.1073/pnas.1116958109

Cite This Page:

University of California - Santa Barbara. "Scientists synthesize first genetically evolved semiconductor material." ScienceDaily. ScienceDaily, 13 June 2012. <www.sciencedaily.com/releases/2012/06/120613133341.htm>.
University of California - Santa Barbara. (2012, June 13). Scientists synthesize first genetically evolved semiconductor material. ScienceDaily. Retrieved April 19, 2015 from www.sciencedaily.com/releases/2012/06/120613133341.htm
University of California - Santa Barbara. "Scientists synthesize first genetically evolved semiconductor material." ScienceDaily. www.sciencedaily.com/releases/2012/06/120613133341.htm (accessed April 19, 2015).

Share This


More From ScienceDaily



More Plants & Animals News

Sunday, April 19, 2015

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Un-Bee-Lievable: Bees on the Loose After Washington Truck Crash

Un-Bee-Lievable: Bees on the Loose After Washington Truck Crash

Reuters - US Online Video (Apr. 17, 2015) A truck carrying honey bees overturns near Lynnwood, Washington, spreading boxes of live bees across the highway. Rough Cut (no reporter narration). Video provided by Reuters
Powered by NewsLook.com
Our Love Of Puppy Dog Eyes Explained By Science

Our Love Of Puppy Dog Eyes Explained By Science

Newsy (Apr. 17, 2015) Researchers found a spike in oxytocin occurs in both humans and dogs when they gaze into each other&apos;s eyes. Video provided by Newsy
Powered by NewsLook.com
Dog Flu Spreading in Midwestern States

Dog Flu Spreading in Midwestern States

AP (Apr. 17, 2015) Dog flu is spreading in several Midwestern states. Dog daycare centers and veterinary offices are taking precautions. (April 17) Video provided by AP
Powered by NewsLook.com
Raw: Rare Whale Spotted in Gulf of Mexico

Raw: Rare Whale Spotted in Gulf of Mexico

AP (Apr. 17, 2015) Researchers from the E/V Nautilus had quite a surprise Tuesday, when a curious sperm whale swam around their remotely operated vehicle in the Gulf of Mexico. Cameras captured the encounter. (April 17) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Plants & Animals

Earth & Climate

Fossils & Ruins

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins