Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Genetic engineering: Speeding up evolution

Generating microbes with useful properties is quicker and easier if multiple genes are modified at the same time

Genetically engineered microorganisms with improved properties are of vital interest in the advancement of modern medicine, as well as the agriculture and food industry. Biotechnology enables modification of specific genes in an organism to produce desirable properties—for example, the ability to withstand extreme environmental conditions or to catalyze a chemical reaction—but modifying complex traits can be time-consuming and expensive due to the large number of genes involved.

Hua Zhao and co-workers at the A*STAR Institute of Chemical and Engineering Sciences1 have now developed a technique called error-prone whole genome amplification (WGA) that enables modification of numerous genes at the same time. To illustrate the potential of the new technique, the researchers applied it to create yeast cells capable of surviving high levels of ethanol.

Metabolism of ethanol in yeast is a complex trait that requires the action of 40 to 60 genes. The researchers isolated DNA from Saccharomyces cerevisiae—one of the most useful forms of yeast widely used in baking and brewing since ancient times—and copied it using the powerful polymerase chain reaction (PCR) technique that amplifies DNA sequences. The key to error-prone WGA is the introduction of random DNA copying errors through imperfect reaction conditions during PCR. The researchers established the mutagenic reaction conditions by adding gene-damaging manganese chloride to the reaction mixture in order to produce DNA with plenty of mutations.

Zhao and co-workers introduced copies of mutated DNA back into S. cerevisiae—a process known as transformation. Normal yeast cells are capable of surviving on a medium containing 7% ethanol. The transformed cells were grown on a medium initially comprising 8.5% ethanol.

The researchers harvested DNA from cells that survived on the high-ethanol medium, and then repeated the error-prone PCR and transformation cycle twice. By the third cycle, cells that were able to survive on a medium containing 9% ethanol had been isolated. The method is an example of directed evolution, which uses the power of natural selection to speed up the process of adapting to changes in environmental conditions in order to develop microorganisms with properties that are biotechnologically useful.

Error-prone WGA is unique in that its direct manipulation of DNA in vitro is slower and more complex than in vivo methods. “The new method enables rapid evolution of complex phenotypes of microorganisms”, says Zhao, whose team has already begun to characterize the proteins and genes in the ethanol-tolerant yeast cells using proteomic and whole genome studies. In future, error-prone WGA may also be extended to other microorganisms.

Luhe, A. L., Tan, L., Wu, J. & Zhao, H. Increase of ethanol tolerance of Saccharomyces cerevisiae by error-prone whole genome amplification. Biotechnology Letters 33, 1007–1011

Lee Swee Heng | Research asia research news
Further information:

More articles from Life Sciences:

nachricht Strong, steady forces at work during cell division
20.10.2016 | University of Massachusetts at Amherst

nachricht Disturbance wanted
20.10.2016 | Max Delbrück Center for Molecular Medicine in the Helmholtz Association

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

Im Focus: Diamonds aren't forever: Sandia, Harvard team create first quantum computer bridge

By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.

"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...

Im Focus: New Products - Highlights of COMPAMED 2016

COMPAMED has become the leading international marketplace for suppliers of medical manufacturing. The trade fair, which takes place every November and is co-located to MEDICA in Dusseldorf, has been steadily growing over the past years and shows that medical technology remains a rapidly growing market.

In 2016, the joint pavilion by the IVAM Microtechnology Network, the Product Market “High-tech for Medical Devices”, will be located in Hall 8a again and will...

Im Focus: Ultra-thin ferroelectric material for next-generation electronics

'Ferroelectric' materials can switch between different states of electrical polarization in response to an external electric field. This flexibility means they show promise for many applications, for example in electronic devices and computer memory. Current ferroelectric materials are highly valued for their thermal and chemical stability and rapid electro-mechanical responses, but creating a material that is scalable down to the tiny sizes needed for technologies like silicon-based semiconductors (Si-based CMOS) has proven challenging.

Now, Hiroshi Funakubo and co-workers at the Tokyo Institute of Technology, in collaboration with researchers across Japan, have conducted experiments to...

All Focus news of the innovation-report >>>



Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

Innovative technique for shaping light could solve bandwidth crunch

20.10.2016 | Physics and Astronomy

Finding the lightest superdeformed triaxial atomic nucleus

20.10.2016 | Physics and Astronomy

NASA's MAVEN mission observes ups and downs of water escape from Mars

20.10.2016 | Physics and Astronomy

More VideoLinks >>>