(Press-News.org) Enzymes are proteins that speed up chemical reactions, such as laundry detergent digesting protein stains, which are otherwise very difficult to remove. A research team led by Professor Kam-bo Wong of the Centre for Protein Science and Crystallography, School of Life Sciences at The Chinese University of Hong Kong demonstrated a fundamental principle in changing the activity of enzymes by means of protein engineering. The findings provide potential insights into the future design of biotechnologically important enzymes, and will be published in next week's issue of the online, open access journal PLoS Biology.
Proteins from thermophiles, organisms that live in high temperatures, are more resistant to heat denaturation than those from mesophiles, organisms that live in moderate temperatures. In nature, enzymes from microbes that thrive in extremely hot habitats like hydrothermal vents can remain stable even at 100 C. These thermophilic enzymes are useful for the biotech industry because of their superior stability.
One intriguing problem is that thermophilic enzymes are less active than their mesophilic homologs despite having similar structures. "It is like two cars having similar engines but one runs 10 times faster than the other. If thermophilic enzymes can be made more active without compromising their stability, it will be of great commercial value to the biotech industry," explained Professor Wong.
Wong's research team used protein engineering methods to investigate why thermophilic enzymes are less active. They discovered that the thermophilic enzyme acylphosphatase has a unique property in that its active site is rigidified by a salt-bridge. Thermophilic enzymes tend to have more stabilizing interactions like salt-bridges. By removing this salt-bridge, his team converted thermophilic properties of acylphosphatase to mesophilic-like properties. Likewise, a mesophilic acylphosphatase from human was engineered to become thermophilic-like by introducing the salt-bridge. Professor Wong's team concluded that the rigidifying salt-bridge increases the activity of enzymes at high temperatures, but at the same time reduces the activity at low temperatures. The principles learned from Professor Wong's study will hopefully guide the improvement of enzymes in the biotech industry.
INFORMATION:
Funding: This work was supported by grants from Research Grants Council, Hong Kong (Project no.: 495005, 476307), UGC Special Equipment Grants, Hong
Kong (Project no.: SEG/CUHK08), and a strategic investment grant from the Chinese University of Hong Kong. The funders had no role in study design, data
collection and analysis, decision to publish, or preparation of the manuscript.
Competing interests statement: The authors declare that no competing interests exist.
Citation: Lam SY, Yeung RCY, Yu T-H, Sze K-H, Wong K-B (2011) A Rigidifying Salt-Bridge Favors the Activity of Thermophilic Enzyme at High Temperatures at the
Expense of Low-Temperature Activity. PLoS Biol 9(3): e1001027. doi:10.1371/journal.pbio.1001027
PLEASE ADD THE LINK TO THE PUBLISHED ARTICLE IN ONLINE VERSIONS OF YOUR REPORT: http://biology.plosjournals.org/perlserv/?request=get-document&doi=10.1371/journal.pbio.1001027
CONTACT:
Chan Tsz-ling (Ms)
Senior Communications and Public Relations Manager
Communications and Public Relations Office
The Chinese University of Hong Kong
Tel : 2609 8896
Fax: 2603 5828
Email: tlamychan@cuhk.edu.hk
END
The wispy arms of the Tarantula Nebula were originally thought to resemble spindly spider legs, giving the nebula its unusual name. The part of the nebula visible in this image from Hubble's Advanced Camera for Surveys is criss-crossed with tendrils of dust and gas churned up by recent supernovae. These supernova remnants include NGC 2060, visible above and to the left of the centre of this image, which contains the brightest known pulsar.
The tarantula's bite goes beyond NGC 2060. Near the edge of the nebula, outside the frame, below and to the right, lie the remains ...
It is important for you to know the possible risks associated with breast augmentation before undergoing the procedure. With the placement of a foreign object into your body, breast augmentation carries an additional set of possible complications not found in other surgical procedures.
Surgical Risks
Just like any other surgical procedure, breast augmentation carries risk factors that pose an unlikely but serious threat to your health. Some serious surgical complications include:
- Allergic reaction to anesthesia - general anesthesia carries rare but potentially ...
Wealthy, well educated people who choose to drink bottled water rather than water from public supplies may be no less exposed to potentially cancer-causing water contaminants, according to new research published in BioMed Central's open access journal Environmental Health.
As part of the EPICURO national bladder cancer study, researchers from all over Spain quizzed 1,270 individuals about their water use and consumption in an effort to discover whether social class has any bearing on exposure to common water disinfection byproducts. High levels of trihalomethanes (THM), ...
Cell phone use is on the rise. The incidence of driving and talking or texting is too. Distracted driving and youthful drivers are two factors that have always impacted accident statistics. The combination of these two factors with the advent of the cell phone has added to an increasingly dangerous trend. Many states have already enacted legislation that place additional restrictions on youthful drivers and cell phone use. There are no such laws in the state of Georgia so even with the number of teen drivers in the greater Atlanta area no restrictions exist.
The statistics ...
Selective serotonin reuptake inhibitors (SSRI) such as Prozac are regularly used to treat severe anxiety and depression. They work by immediately increasing the amount of serotonin in the brain and by causing long term changes in brain function. However it can take weeks of treatment before a patient feels any effect and both beneficial effects and side effects can persist after treatment is stopped. New research published by BioMed Central's open access journal Molecular Brain investigates physiological changes within the brain that may be caused by SSRI treatment.
The ...
A new laser device created at the University of Central Florida could make high-speed computing faster and more reliable, opening the door to a new age of the Internet.
Professor Dennis Deppe's miniature laser diode emits more intense light than those currently used. The light emits at a single wavelength, making it ideal for use in compact disc players, laser pointers and optical mice for computers, in addition to high-speed data transmission.
Until now, the biggest challenge has been the failure rate of these tiny devices. They don't work very well when they face ...
U.S. Department of Transportation has issued a new rule aimed at preventing occupant ejections in passenger vehicles.
The rule, issued by the National Highway Traffic Safety Administration (NHTSA), is designed to help reduce the number of people partially or completely ejected through side windows during rollover crashes, and will be phased in from 2013 to 2018.
New side curtain airbags will be used to contain passengers inside the vehicle, though the standards require the airbag to prevent ejection even if the widow is open.
The agency has also upgraded the roof ...
A new theory suggests an equation for identifying the cause and level of our responses to any humorous stimuli: h = m x s
The theory argues that human beings are more reliant for their behavioural instruction on culturally inherited information than any other species, and that the accuracy of that information is therefore of unparalleled importance. Yet the individual is exposed to the continual threats of error and deception, which can seriously affect their chances of survival and success.
To compensate, humour rewards us for seeing through misinformation that has ...
Research from Karolinska Institutet in Sweden shows, that a specific inflammatory factor may be important in the development of the heart valve disease aortic stenosis. The results suggest that anti-inflammatory medication could be a possible new treatment.
Aortic stenosis is the most common heart valve disease, which is caused by calcium deposits and a narrowing of the aortic valve. This is typically seen in the elderly, but can also be caused by a congenital defect. Aortic stenosis is currently treated by surgical replacement of the diseased valve, but research is on-going ...
The Philadelphia law firm of Silvers, Langsam & Weitzman, P.C., known throughout the area as MyPhillyLawyer, is launching a brand new informational birth injury website. The website, www.birthinjuryinfo.org, will be a resource for families and parents of babies and children who suffered a birth injury as a result of negligent care during pregnancy or childbirth.
The birth injury lawyers at MyPhillyLawyer are committed to providing relevant and up-to-date information about birth injuries, such as Erb's Palsy, Cerebral Palsy, brain injuries and other serious and life-threatening ...
