Researchers devise biomaterial that could be used in the detection of toxins and pollutants

Jul 01, 2011
TCD researchers devise biomaterial that could be used in the detection of toxins and pollutants

(PhysOrg.com) -- In research recently published in the leading international journal PNAS, Trinity researchers exploit the potential of a biomaterial to reveal the activity of important fat metabolising enzymes. The findings show that the biomaterial could possibly be used in the future detection of toxins, explosives, pollutants, and medicines.

Detection devices have superior sensitivity when the sensor itself can be packaged at high density.  Certain proteins that are found in the membranes of cells can act as sensors.  However, the density with which cellular membranes can be packed in a sensor of a defined volume can limit the application.  In this study, use was made of a particular form of matter, referred to as a liquid crystal or mesophase, that behaved as a densely packed mimic for cellular membranes.

Certain naturally occurring lipids or fats, when combined with water spontaneously form liquid crystals.  One of these lipids called monoolein is a product of fat digestion.  The liquid crystalline cubic phase that monoolein forms, when wet, has the lipid arranged as a bilayer just two molecules thick that is bathed on either side by water.  This hydrated bilayer resembles the membrane that surrounds the cells in living organisms. The cubic phase is particularly notable as a liquid crystal in the extraordinary density with which it packages the membrane and the enormous surface area that it has. Thus, for example, a mere thimbleful of the cubic phase has enough surface area to cover a football field.

The research conducted by Trinity’s Professor of Membrane Structural and Functional Biology, Martin Caffrey and Research Associate Dr  Dianfan Li in the School of Medicine and School of Biochemistry & Immunology used the cubic phase; but the cubic phase made from hydrated fat alone was useless.  It needed to have a membrane protein sensor incorporated into it and the protein needed to be active.  The test sensor used in the research was a membrane protein, referred to as DgkA.  DgkA is an enzyme that interconverts the fatty components of natural cellular membranes.  The enzyme was produced in E. coli bacteria, using recombinant DNA technology, as an inactive or dead ‘scrambled egg’ type of insoluble aggregate.   ‘Life’ was breathed back into the enzyme by dissolving the aggregated protein in a soapy solution and inserting it into the membrane of the cubic phase.  In this new and quite artificial environment the researchers showed that the protein had regained its original native activity and that it could behave as a model sensor.

The research sets the stage for the exploitation of this most extraordinary of biomaterials.  These include its use in high density, high sensitivity biosensors for the detection of biological molecules such as hormones, proteins, carbohydrates, and lipids, as well as toxins, explosives, pollutants, and drugs. 

Explore further: Laser optical tweezers reveal how malaria parasites infect red blood cells (w/ Video)

Related Stories

Scientists discover how dengue virus infects cells

Oct 12, 2010

(PhysOrg.com) -- National Institutes of Health researchers have discovered a key step in how the dengue virus infects a cell. The discovery one day may lead to new drugs to prevent or treat the infection.

Enzyme enhances, erases long-term memories in rats

Mar 04, 2011

 (PhysOrg.com) -- Even long after it is formed, a memory in rats can be enhanced or erased by increasing or decreasing the activity of a brain enzyme, say researchers supported, in part, by the National ...

FDA announces new limits on high-dose simvastatin (Zocor)

Jun 09, 2011

The United States Food and Drug Administration (FDA) today announced new limitations to the use of high-dose simvastatin, due to the increased risk of muscle pain and weakness (myopathy) and in rare cases, kidney damage and ...

New imaging technology predicts fracture risk

Oct 27, 2010

(PhysOrg.com) -- A new method for identifying which bones have a high risk of fracture, and for monitoring the effectiveness of new bone-strengthening drugs and techniques, has been developed by scientists ...

Recommended for you

Treating pain by blocking the 'chili-pepper receptor'

1 hour ago

Biting into a chili pepper causes a burning spiciness that is irresistible to some, but intolerable to others. Scientists exploring the chili pepper's effect are using their findings to develop a new drug ...

Moving single cells around—accurately and cheaply

21 hours ago

Scientists at the Houston Methodist Research Institute have figured out how to pick up and transfer single cells using a pipette—a common laboratory tool that's been tweaked slightly. They describe this ...

The difficult question of Clostridium difficile

Aug 19, 2014

The bacterium Clostridium difficile causes antibiotic-related diarrhoea and is a growing problem in the hospital environment and elsewhere in the community. Understanding how the microbe colonises the hu ...

User comments : 0