Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Scientists sequence genome of the N2-fixing, soil-living bacterium Azotobacter vinelandii

22.06.2009
A collaboration of researchers, which includes scientists at the Virginia Bioinformatics Institute (VBI) and Virginia Tech, have completed the genome sequence of Azotobacter vinelandii, uncovering important genetic information that will contribute to a more complete understanding of the biology of this versatile, soil-living bacterium.

The work will help advance research on A. vinelandii's role as a model study organism for investigation of nitrogen fixation and other biochemical processes. It will also pave the way for new applications in biotechnology, including the possible use of A. vinelandii as a "factory" for the production of other proteins, in particular those that may be damaged by the presence of oxygen.

A. vinelandii lives in soil and has the ability to convert nitrogen from the atmosphere into ammonia via bacterial enzymes called nitrogenases. Nitrogen fixation is essential for life since different nitrogen-containing molecules are used to produce DNA and the amino acids that are the building blocks of proteins. For most bacteria, the nitrogenase enzymes involved in nitrogen fixation are very susceptible to destruction by oxygen. A. vinelandii is one of the few bacteria that can fix nitrogen in the presence of oxygen, using three distinct nitrogenase systems.

The work of the Azotobacter vinelandii genome project team, which will be featured on the cover of the second July 2009 issue (14) of the Journal of Bacteriology*, identifies unique features of the A. vinelandii genome that explain how the bacteria is involved in oxygen-sensitive reactions such as nitrogen fixation, while maintaining strictly aerobic metabolism.

A. vinelandii has one of the highest respiratory rates of any known bacterium and has the capacity to maintain low levels of cytoplasmic oxygen through a process called respiratory protection. The sequence of the bacteria's genome allowed the team of researchers to identify the genes involved in respiration, including those responsible for respiratory protection. Genome analysis helped pinpoint the chromosomal location of the three known oxygen-sensitive nitrogenases, as well as the genes that code for other oxygen-sensitive enzymes such as carbon-monoxide dehydrogenase and a formate dehydrogenase. The sequence also provided important information on the genes that code for alginate, a polymer that further protects the organism from excess oxygen by forming a physical barrier around the bacterium.

"A. vinelandii is an attractive model organism for biochemical studies because of its ability to produce high yields of quality enzymes," said João Setubal, associate professor at VBI and the Department of Computer Science at Virginia Tech. "The findings in this study provide new prospects for the wider application of this bacterium as a factory for the production and characterization of oxygen-sensitive proteins through the use of genetic approaches to achieve high-level protein expression."

According to Ray Dixon, project lead in Molecular Biology at the John Innes Centre in the United Kingdom, "The international collaboration created by the Azotobacter genome project was an integral part of the discovery of these unexpected anaerobic processes in A. vinelandii, which confirmed the importance of this organism as a host for the expression and purification of oxygen-sensitive enzymes."

The work will also provide more information about the unique biosynthetic pathways involved in the bacteria's ability to adapt its metabolism to diverse sources of nutrients. For example, if no carbon source is present, A. vinelandii will undergo a differentiation process, forming cysts that are resistant to desiccation and other chemical and physical challenges.

A. vinelandii belongs to the Pseudomonadaceae family. The completion of the A. vinelandii genome will serve as an essential phylogenetic anchor point for comparative genomics work with other systems. This research has also helped the Azotobacter vinelandii genome project expand its existing undergraduate training platform in genomics technology. Undergraduate researchers from around the world worked on many aspects of the project, including the finishing, annotation, bioinformatics, and analytical phases. This work provided critical training for these new scientists in the fields of genomics and bioinformatics.

"The key to the success of this project was an extremely effective multinational collaboration between Azotobacter biologists and our core genomics team," explained Derek Wood, associate professor in Seattle Pacific University's Department of Biology and the University of Washington's Department of Microbiology. "Numerous undergraduate researchers both in the classroom and in the laboratory worked closely with the team on annotation and analyses. This multilevel interdisciplinary collaboration led to an excellent annotation and informed analysis of this model bacterial system and provided an excellent training platform for our undergraduate partners."

According to Dennis Dean, biochemistry professor in Virginia Tech's College of Agriculture and Life Sciences and director of the Fralin Life Science Institute, "Given the long history of Virginia Tech's research involving nitrogen fixation studies, including work from J.S. Chen, Bill Newton, and others, it is particularly satisfying that the university has contributed to this important endeavor."

The A. vinelandii genome sequence involved work from researchers from VBI, Virginia Tech, Wake Forest University, Monsanto, the Norwegian University of Science and Technology, Universidad Nacional Autónoma de México, Centro de Biotecnologia y Genomica de Plantas (Spain), Universidade Federal do Mato Grosso do Sul (Brazil), Hiram College, Centro de Estudios de Biodiversidad y Biotecnologia (Argentina), Midwestern University, Seattle Pacific University, University of Arizona, Macquarie University (Australia), the University of Wisconsin-Madison, the Sainsbury Laboratory (United Kingdom), the John Innes Centre (United Kingdom), and the University of Washington.

* João C. Setubal, Patricia dos Santos, Barry S. Goldman, Helga Ertesvåg, Guadelupe Espin, Luis M. Rubio, Svein Valla, Nalvo F. Almeida, Divya Balasubramanian, Lindsey Cromes, Leonardo Curatti, Zijin Du, Eric Godsy, Brad Goodner, Kaitlyn Hellner-Burris, José A. Hernandez, Katherine Houmiel, Juan Imperial, Christina Kennedy, Timothy J. Larson, Phil Latreille, Lauren S. Ligon, Jing Lu, Mali Mærk, Nancy M. Miller, Stacie Norton, Ina P. O'Carroll1, Ian Paulsen, Estella C. Raulfs, Rebecca Roemer, James Rosser, Daniel Segura, Steve Slater, Shawn L. Stricklin, David J. Studholme, Jian Sun, Carlos J. Viana, Erik Wallin, Baomin Wang, Cathy Wheeler, Huijun Zhu, Dennis R. Dean, Ray Dixon, and Derek Wood (2009) The genome sequence of Azotobacter vinelandii, an obligate aerobe specialized to support diverse anaerobic metabolic processes. Journal of Bacteriology, May 8, 2009, Epub ahead of print, oi:10.1128/JB.00504-09 (http://jb.asm.org/cgi/content/short/JB.00504-09v1).

About the Azotobacter vinelandii genome project

The Azotobacter vinelandii genome project brought together extensive expertise from five independent groups with significant experience in Azotobacter biology, genomics, bioinformatics, and undergraduate education with the goal of producing a finished, well-annotated genome sequence of Azotobacter vinelandii strain DJ and expanding existing undergraduate training platform in genomics technology at both participating and off-site institutions. The work was supported by a National Science Foundation (NSF) grant (#0523357) and M.J. Murdock Charitable Trust Life Sciences Program grants (2004262:JVZ and 2006245:JVZ).

About the Virginia Bioinformatics Institute

The Virginia Bioinformatics Institute (VBI) at Virginia Tech has a research platform centered on understanding the "disease triangle" of host-pathogen-environment interactions in plants, humans and other animals. By successfully channeling innovation into transdisciplinary approaches that combine information technology and biology, researchers at VBI are addressing some of today's key challenges in the biomedical, environmental and plant sciences.

Susan Bland | EurekAlert!
Further information:
http://www.vbi.vt.edu/

More articles from Life Sciences:

nachricht Cancer diagnosis: no more needles?
25.05.2018 | Christian-Albrechts-Universität zu Kiel

nachricht Less is more? Gene switch for healthy aging found
25.05.2018 | Leibniz-Institut für Alternsforschung - Fritz-Lipmann-Institut e.V. (FLI)

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Powerful IT security for the car of the future – research alliance develops new approaches

The more electronics steer, accelerate and brake cars, the more important it is to protect them against cyber-attacks. That is why 15 partners from industry and academia will work together over the next three years on new approaches to IT security in self-driving cars. The joint project goes by the name Security For Connected, Autonomous Cars (SecForCARs) and has funding of €7.2 million from the German Federal Ministry of Education and Research. Infineon is leading the project.

Vehicles already offer diverse communication interfaces and more and more automated functions, such as distance and lane-keeping assist systems. At the same...

Im Focus: Molecular switch will facilitate the development of pioneering electro-optical devices

A research team led by physicists at the Technical University of Munich (TUM) has developed molecular nanoswitches that can be toggled between two structurally different states using an applied voltage. They can serve as the basis for a pioneering class of devices that could replace silicon-based components with organic molecules.

The development of new electronic technologies drives the incessant reduction of functional component sizes. In the context of an international collaborative...

Im Focus: LZH showcases laser material processing of tomorrow at the LASYS 2018

At the LASYS 2018, from June 5th to 7th, the Laser Zentrum Hannover e.V. (LZH) will be showcasing processes for the laser material processing of tomorrow in hall 4 at stand 4E75. With blown bomb shells the LZH will present first results of a research project on civil security.

At this year's LASYS, the LZH will exhibit light-based processes such as cutting, welding, ablation and structuring as well as additive manufacturing for...

Im Focus: Self-illuminating pixels for a new display generation

There are videos on the internet that can make one marvel at technology. For example, a smartphone is casually bent around the arm or a thin-film display is rolled in all directions and with almost every diameter. From the user's point of view, this looks fantastic. From a professional point of view, however, the question arises: Is that already possible?

At Display Week 2018, scientists from the Fraunhofer Institute for Applied Polymer Research IAP will be demonstrating today’s technological possibilities and...

Im Focus: Explanation for puzzling quantum oscillations has been found

So-called quantum many-body scars allow quantum systems to stay out of equilibrium much longer, explaining experiment | Study published in Nature Physics

Recently, researchers from Harvard and MIT succeeded in trapping a record 53 atoms and individually controlling their quantum state, realizing what is called a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

In focus: Climate adapted plants

25.05.2018 | Event News

Save the date: Forum European Neuroscience – 07-11 July 2018 in Berlin, Germany

02.05.2018 | Event News

Invitation to the upcoming "Current Topics in Bioinformatics: Big Data in Genomics and Medicine"

13.04.2018 | Event News

 
Latest News

In focus: Climate adapted plants

25.05.2018 | Event News

Flow probes from the 3D printer

25.05.2018 | Machine Engineering

Less is more? Gene switch for healthy aging found

25.05.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>