Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Biochemists Identify Protease Substrates Important to Bacterial Growth

28.06.2013
Reporting this month in Molecular Microbiology, Peter Chien and colleagues at the University of Massachusetts Amherst describe using a combination of biochemistry and mass spectrometry to “trap” scores of new candidate substrates of the protease ClpXP to reveal how protein degradation is critical to cell cycle progression and bacterial development. The new understanding could lead to identifying new antibiotic targets.

As Chien (pronounced Chen) explains, to carry out fundamental life processes such as growing and dividing, cells must orchestrate, in time and location, the production and degradation of hundreds of protein substrates. Even in simple bacteria, protein degradation is critical for making sure these organisms can grow and respond to their environment properly.


Peter Chien

Caulobacter crescentus (above) generates radically different cell types upon division. The ClpXP protease (illustrated below) recognizes and destroys many protein substrates that allow Caulobacter to differentiate into these different cell types. New work identifying scores of new candidate substrates of ClpXP to reveal how protein degradation is critical to cell cycle progression and bacterial development could lead to new antibiotic targets.

Scientists have known that a group of protein machines called energy-dependent proteases are responsible for the majority of this degradation, but what targets these machines recognize and how they do it has been unknown in many cases.

With the new series of experiments in the model bacteria Caulobacter crescentus in the Chien biochemistry and molecular biology laboratory, much more is now understood, he says. “We first generated a protease mutant that could recognize but not destroy its targets, acting as a ‘trap’ for protease substrates. After purifying this trap from living cells, we used mass spectrometry to identify proteins that were caught, finding over a hundred new candidate substrates. These targets covered all aspects of bacterial growth, including DNA replication, transcription and cytoskeletal changes.”

Next, they focused on one of these new targets in detail, a protein called TacA. Caulobacter grow by making two different cell types every time they divide. TacA is responsible for making sure that one of these cell types forms properly.

“We used biochemistry and highly purified proteins to identify what parts of TacA were important for degradation by the ClpXP protease,” Chien says. “We then made mutants of TacA that could not be degraded and found that when we expressed them in bacteria, these cells failed to properly develop into the correct cell types. Because developmental changes are essential for pathogenic bacteria to invade their host, these insights could potentially identify new antibiotic targets.”

The work was funded by a grant from the National Institute of General Medical Sciences at the National Institutes of Health and by UMass Amherst.

Peter Chien | Newswise
Further information:
http://www.umass.edu

More articles from Life Sciences:

nachricht Plant escape from waterlogging
17.10.2017 | Christian-Albrechts-Universität zu Kiel

nachricht Study suggests oysters offer hot spot for reducing nutrient pollution
17.10.2017 | Virginia Institute of Marine Science

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Breaking: the first light from two neutron stars merging

Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.

Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....

Im Focus: Smart sensors for efficient processes

Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).

When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...

Im Focus: Cold molecules on collision course

Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.

How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...

Im Focus: Shrinking the proton again!

Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.

It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...

Im Focus: New nanomaterial can extract hydrogen fuel from seawater

Hybrid material converts more sunlight and can weather seawater's harsh conditions

It's possible to produce hydrogen to power fuel cells by extracting the gas from seawater, but the electricity required to do it makes the process costly. UCF...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ASEAN Member States discuss the future role of renewable energy

17.10.2017 | Event News

World Health Summit 2017: International experts set the course for the future of Global Health

10.10.2017 | Event News

Climate Engineering Conference 2017 Opens in Berlin

10.10.2017 | Event News

 
Latest News

Study suggests oysters offer hot spot for reducing nutrient pollution

17.10.2017 | Life Sciences

Breaking: the first light from two neutron stars merging

17.10.2017 | Physics and Astronomy

World first for reading digitally encoded synthetic molecules

17.10.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>