Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Researchers Develop New Method for Facile Identification of Proteins in Bacterial Cells

04.05.2005


Researchers at the Johns Hopkins Bloomberg School of Public Health have developed a new method for identifying specific proteins in whole cell extracts of microorganisms using traditional peptide mass fingerprinting (PMF). The key to the new method, according to the researchers, is a “shortcut” for preparing samples that makes PMF faster and more economical. By reducing the cost of protein identification, they believe PMF can become an economical tool for monitoring and evaluating the effectiveness of microorganisms used in environmental cleanup. The researchers used a dioxin-eating organism to demonstrate the capabilities of their methodology, which they described in an article published in the May 2005 edition of Applied and Environmental Microbiology.



PMF typically involves elaborate sample preparation. A protein mixture is spread across a gel and separated into individual proteins, which are scooped out of the gel and cut with protein scissors into predictable, small pieces called peptides. The samples are then analyzed using matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS), which identifies protein fragments based on the time they need to travel a defined distance when being accelerated in a vacuum.

In their study, Rolf U. Halden, PhD, PE, assistant professor in the Department of Environmental Health Sciences Bloomberg School of Public Health and his colleagues demonstrate how PMF and mass spectrometry are used to identify a unique dioxin-degrading enzyme in a soup of hundreds of cell proteins. The technique avoids elaborate conventional sample preparation steps by coaxing the cells into mass production of the protein the researchers wish to analyze.


“Finding a specific target in a mixture of hundreds of proteins can be likened to finding the proverbial needle in the haystack; this task can be performed much faster and more economically if you have more needles—and that’s exactly what our method is based on,” explained Dr. Halden. “Instead of spending a lot of time and resources on eliminating the background noise to find the signal, our method increases the signal upfront so that it stands out above the background noise. By forcing an up-regulation of enzyme expression in the bacterium of interest, our target can be identified amidst all of the other cell components,” he said.

Halden and his colleagues tested their technique using Sphingomonas wittichii strain RW1, the only bacterium known to consume the backbone of toxic polychlorinated dibenzo-p-dioxins and dibenzofurans as a food source. The researchers already knew that feeding dioxins to RW1 would cause an increased enzyme level as the bacterium consumed the model pollutant. Their study shows that this increase can be easily identified by PMF using mass spectrometry.

“Our procedure simplifies the entire identification process,” said David Colquhoun, MS, a doctoral fellow with the Johns Hopkins Center for a Livable Future, “With the new tool, we can conveniently and rapidly identify both pollutant-degrading bacteria and their characteristic proteins that effect pollutant transformation.”

“This method represents a new investigative tool in bioremediation, which is the science of using biological organisms as a means of decontaminating polluted soils and water,” said Dr. Halden.

Johns Hopkins University is seeking partners who would like to license this patent-pending methodology. Inquiries may be directed to Deborah Alper at the Johns Hopkins Bloomberg School of Public Health at dalper@jhsph.edu or 443-287-0402.

“Identification and Phenotypic Characterization of Sphingomonas wittichii Strain RW1 by Peptide Mass Fingerprinting Using Matrix-Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry” was written by Rolf U. Halden, David R. Colquhoun and E.S. Wisniewski.

Funding was provided by grants from the Johns Hopkins Bloomberg School of Public Health Technology Transfer Committee, the National Institutes of Health Training Grant and the Johns Hopkins Center for a Livable Future.

Public Affairs media contacts for the Johns Hopkins Bloomberg School of Public Health: Tim Parsons or Kenna Lowe at 410-955-6878 or paffairs@jhsph.edu.

Tim Parsons | EurekAlert!
Further information:
http://www.jhsph.edu

More articles from Life Sciences:

nachricht Zebrafish's near 360 degree UV-vision knocks stripes off Google Street View
22.06.2018 | University of Sussex

nachricht New cellular pathway helps explain how inflammation leads to artery disease
22.06.2018 | Cedars-Sinai Medical Center

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Superconducting vortices quantize ordinary metal

Russian researchers together with their French colleagues discovered that a genuine feature of superconductors -- quantum Abrikosov vortices of supercurrent -- can also exist in an ordinary nonsuperconducting metal put into contact with a superconductor. The observation of these vortices provides direct evidence of induced quantum coherence. The pioneering experimental observation was supported by a first-ever numerical model that describes the induced vortices in finer detail.

These fundamental results, published in the journal Nature Communications, enable a better understanding and description of the processes occurring at the...

Im Focus: Temperature-controlled fiber-optic light source with liquid core

In a recent publication in the renowned journal Optica, scientists of Leibniz-Institute of Photonic Technology (Leibniz IPHT) in Jena showed that they can accurately control the optical properties of liquid-core fiber lasers and therefore their spectral band width by temperature and pressure tuning.

Already last year, the researchers provided experimental proof of a new dynamic of hybrid solitons– temporally and spectrally stationary light waves resulting...

Im Focus: Overdosing on Calcium

Nano crystals impact stem cell fate during bone formation

Scientists from the University of Freiburg and the University of Basel identified a master regulator for bone regeneration. Prasad Shastri, Professor of...

Im Focus: AchemAsia 2019 will take place in Shanghai

Moving into its fourth decade, AchemAsia is setting out for new horizons: The International Expo and Innovation Forum for Sustainable Chemical Production will take place from 21-23 May 2019 in Shanghai, China. With an updated event profile, the eleventh edition focusses on topics that are especially relevant for the Chinese process industry, putting a strong emphasis on sustainability and innovation.

Founded in 1989 as a spin-off of ACHEMA to cater to the needs of China’s then developing industry, AchemAsia has since grown into a platform where the latest...

Im Focus: First real-time test of Li-Fi utilization for the industrial Internet of Things

The BMBF-funded OWICELLS project was successfully completed with a final presentation at the BMW plant in Munich. The presentation demonstrated a Li-Fi communication with a mobile robot, while the robot carried out usual production processes (welding, moving and testing parts) in a 5x5m² production cell. The robust, optical wireless transmission is based on spatial diversity; in other words, data is sent and received simultaneously by several LEDs and several photodiodes. The system can transmit data at more than 100 Mbit/s and five milliseconds latency.

Modern production technologies in the automobile industry must become more flexible in order to fulfil individual customer requirements.

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Munich conference on asteroid detection, tracking and defense

13.06.2018 | Event News

2nd International Baltic Earth Conference in Denmark: “The Baltic Sea region in Transition”

08.06.2018 | Event News

ISEKI_Food 2018: Conference with Holistic View of Food Production

05.06.2018 | Event News

 
Latest News

Rapid water formation in diffuse interstellar clouds

25.06.2018 | Physics and Astronomy

Using tree-fall patterns to calculate tornado wind speed

25.06.2018 | Earth Sciences

'Stealth' material hides hot objects from infrared eyes

25.06.2018 | Power and Electrical Engineering

VideoLinks
Science & Research
Overview of more VideoLinks >>>