Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Researchers Discover New DNA Binding Activity of E. coli Protein

01.08.2008
Northeastern University scientists have discovered a new and unique DNA binding property of a protein in E. coli. Penny J. Beuning, Assistant Professor in the Department of Chemistry and Chemical Biology, spent the last two years researching double and single-stranded DNA binding of E. coli DNA polymerase III alpha protein and notes that her findings have potential for developing a new antibacterial target.

Beuning's results have recently been published in ACS Chemical Biology in an article titled "Distinct Double- and Single-Stranded DNA Binding of E. coli Replicative DNA Polymerase III Alpha Subunit".

This work represents the collaborative effort of the Northeastern laboratories of Beuning and Mark C. Williams, Associate Professor of Physics, and involved researchers Micah J. McCauley, Leila Shokri, and Jana Sefcikova from both laboratories. Additionally, Èeslovas Venclovas, of the Institute of Biotechnology in Lithuania, provided computational modeling expertise to the project.

The project took advantage of the single-molecule expertise in the Williams laboratory and used a series of optical tweezers experiments to find that the DNA polymerase subunit of the 10-subunit bacterial replicative DNA enzyme has affinity for both double and single-stranded DNA in distinct subdomains of the protein.

... more about:
»Beuning »Coli »DNA »single-stranded

DNA polymerase III is responsible for copying the entire genome of E. coli every time a cell divides. The alpha subunit is the enzyme that actually copies the DNA, and that activity is well-known. However, there are additional parts of the protein that were not characterized and that the researches suspected had DNA binding activity. The researchers first confirmed that the protein binds both double- and single-stranded DNA. Using protein engineering methods to isolate protein domains, they were able to localize the two different DNA binding activities to two different domains of the protein.

"The single-stranded DNA binding component appears to be passive, because the protein does not assist in melting but instead binds to single-stranded regions which are already separated by force," said Beuning. "Detecting this kind of binding would be difficult or impossible using traditional methods of assaying DNA binding activity."

The researchers' results demonstrated that single-stranded DNA binding is localized to an OB-fold domain while a tandem, helix-hairpin-helix motif contributes significantly to double-stranded DNA binding. Single-stranded DNA binding by the subunit occurs only after single-stranded DNA has been fully melted by force. This unusual behavior, noted Beuning, may be functionally important as single-stranded DNA binding will likely occur only after other replication processes create single-stranded DNA.

“It is crucial to understand how these kinds of massive biological machines function in the cellular environment in order to fully exploit their potential as drug targets,” added Beuning.

About Northeastern

Founded in 1898, Northeastern University is a private research university located in the heart of Boston. Northeastern is a leader in interdisciplinary research, urban engagement, and the integration of classroom learning with real-world experience. The university's distinctive cooperative education program, where students alternate semesters of full-time study with semesters of paid work in fields relevant to their professional interests and major, is one of the largest and most innovative in the world. The University offers a comprehensive range of undergraduate and graduate programs leading to degrees through the doctorate in six undergraduate colleges, eight graduate schools, and two part-time divisions.

Samantha Fodrowski | Newswise Science News
Further information:
http://www.northeastern.edu

Further reports about: Beuning Coli DNA single-stranded

More articles from Life Sciences:

nachricht Cnidarians remotely control bacteria
21.09.2017 | Christian-Albrechts-Universität zu Kiel

nachricht Immune cells may heal bleeding brain after strokes
21.09.2017 | NIH/National Institute of Neurological Disorders and Stroke

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Highly precise wiring in the Cerebral Cortex

Our brains house extremely complex neuronal circuits, whose detailed structures are still largely unknown. This is especially true for the so-called cerebral cortex of mammals, where among other things vision, thoughts or spatial orientation are being computed. Here the rules by which nerve cells are connected to each other are only partly understood. A team of scientists around Moritz Helmstaedter at the Frankfiurt Max Planck Institute for Brain Research and Helene Schmidt (Humboldt University in Berlin) have now discovered a surprisingly precise nerve cell connectivity pattern in the part of the cerebral cortex that is responsible for orienting the individual animal or human in space.

The researchers report online in Nature (Schmidt et al., 2017. Axonal synapse sorting in medial entorhinal cortex, DOI: 10.1038/nature24005) that synapses in...

Im Focus: Tiny lasers from a gallery of whispers

New technique promises tunable laser devices

Whispering gallery mode (WGM) resonators are used to make tiny micro-lasers, sensors, switches, routers and other devices. These tiny structures rely on a...

Im Focus: Ultrafast snapshots of relaxing electrons in solids

Using ultrafast flashes of laser and x-ray radiation, scientists at the Max Planck Institute of Quantum Optics (Garching, Germany) took snapshots of the briefest electron motion inside a solid material to date. The electron motion lasted only 750 billionths of the billionth of a second before it fainted, setting a new record of human capability to capture ultrafast processes inside solids!

When x-rays shine onto solid materials or large molecules, an electron is pushed away from its original place near the nucleus of the atom, leaving a hole...

Im Focus: Quantum Sensors Decipher Magnetic Ordering in a New Semiconducting Material

For the first time, physicists have successfully imaged spiral magnetic ordering in a multiferroic material. These materials are considered highly promising candidates for future data storage media. The researchers were able to prove their findings using unique quantum sensors that were developed at Basel University and that can analyze electromagnetic fields on the nanometer scale. The results – obtained by scientists from the University of Basel’s Department of Physics, the Swiss Nanoscience Institute, the University of Montpellier and several laboratories from University Paris-Saclay – were recently published in the journal Nature.

Multiferroics are materials that simultaneously react to electric and magnetic fields. These two properties are rarely found together, and their combined...

Im Focus: Fast, convenient & standardized: New lab innovation for automated tissue engineering & drug

MBM ScienceBridge GmbH successfully negotiated a license agreement between University Medical Center Göttingen (UMG) and the biotech company Tissue Systems Holding GmbH about commercial use of a multi-well tissue plate for automated and reliable tissue engineering & drug testing.

MBM ScienceBridge GmbH successfully negotiated a license agreement between University Medical Center Göttingen (UMG) and the biotech company Tissue Systems...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

“Lasers in Composites Symposium” in Aachen – from Science to Application

19.09.2017 | Event News

I-ESA 2018 – Call for Papers

12.09.2017 | Event News

EMBO at Basel Life, a new conference on current and emerging life science research

06.09.2017 | Event News

 
Latest News

Comet or asteroid? Hubble discovers that a unique object is a binary

21.09.2017 | Physics and Astronomy

Cnidarians remotely control bacteria

21.09.2017 | Life Sciences

Monitoring the heart's mitochondria to predict cardiac arrest?

21.09.2017 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>