Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

UK scientists crack lobster shell colour puzzle

29.07.2002


UK researchers announced a first this week when they reported their discovery of how lobsters change colour from the blue-purple of their ocean-floor camouflage to the distinctive orange-red when cooked.



Writing in the journal Proceedings of the National Academy of Science, scientists from Imperial College London, University of Manchester, Daresbury Laboratory and Royal Holloway, University of London describe how they have solved the structure of a key part of the lobster shell protein, Beta-Crustacyanin.

Visualising the key subunit of this large molecule allows them to show how structural changes within it can bend the shape of the colour molecule bound to it, Astaxanthin, to make different colours.


Astaxanthin, a carotenoid, has its light-absorption properties altered by the subunit as it undergoes the bathochromic shift. In its free, un-bound form it is orange, but when tightly held by Crustacyanins clamp-like protein subunits, it is flattened and becomes blue.

The effect of cooking lobster is to denature the Crustacyanin unit so much that it becomes permanently stuck in the free form, coloured orange.

Dr Naomi Chayen of Imperial College London said: “This could lead to an important new use of Astaxanthin as a drug-delivery mechanism for medicines that are insoluble in water, and give designers of new food colourants or dyestuffs an interesting new capability.

“It also concludes painstaking research begun by this UK team in 1995, and finally settles a question which has continued to intrigue biologists since Nobel Prize winner George Wald first drew attention to it in 1948.”

In order to gain insight into the mechanism of the molecules that drive the intriguing colour change, it is necessary to look at their 3 - dimensional structure, preferably by X-ray crystallography which requires crystals.

Initial separation and isolation work by Dr Peter Zagalsky of Royal Holloway, University of London, yielded a sample of highly pure Crustacyanin which was then handed to crystal grower Dr Naomi Chayen of Imperial College London.

Dr Chayen made use of the unique Microbatch method of growing crystals under oil (of which she is a co-developer), after the classic crystallization methods repeatedly failed.

She almost abandoned the experiments to grow the crystals after two months, but her persistence paid off as the solution she had carefully put to one side finally produced beautiful blue crystals after four months.

Team members at University of Manchester led by Professor John Helliwell used X-ray crystallographic techniques, including innovative use of softer X-rays on the Synchrotron Radiation Source at Daresbury Laboratory with Dr Pierre Rizkallah, to establish the B-Crustacyanin structure in detail. The Manchester Structural Chemistry Laboratory then harnessed the crystal structure models to account for the colour change.

The Leverhulme Trust funded the research.

Tony Stephenson | alfa

More articles from Life Sciences:

nachricht Water world
20.11.2017 | Washington University in St. Louis

nachricht Carefully crafted light pulses control neuron activity
20.11.2017 | University of Illinois at Urbana-Champaign

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: A “cosmic snake” reveals the structure of remote galaxies

The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.

Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...

Im Focus: Visual intelligence is not the same as IQ

Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.

That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...

Im Focus: Novel Nano-CT device creates high-resolution 3D-X-rays of tiny velvet worm legs

Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.

During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....

Im Focus: Researchers Develop Data Bus for Quantum Computer

The quantum world is fragile; error correction codes are needed to protect the information stored in a quantum object from the deteriorating effects of noise. Quantum physicists in Innsbruck have developed a protocol to pass quantum information between differently encoded building blocks of a future quantum computer, such as processors and memories. Scientists may use this protocol in the future to build a data bus for quantum computers. The researchers have published their work in the journal Nature Communications.

Future quantum computers will be able to solve problems where conventional computers fail today. We are still far away from any large-scale implementation,...

Im Focus: Wrinkles give heat a jolt in pillared graphene

Rice University researchers test 3-D carbon nanostructures' thermal transport abilities

Pillared graphene would transfer heat better if the theoretical material had a few asymmetric junctions that caused wrinkles, according to Rice University...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Ecology Across Borders: International conference brings together 1,500 ecologists

15.11.2017 | Event News

Road into laboratory: Users discuss biaxial fatigue-testing for car and truck wheel

15.11.2017 | Event News

#Berlin5GWeek: The right network for Industry 4.0

30.10.2017 | Event News

 
Latest News

Antarctic landscape insights keep ice loss forecasts on the radar

20.11.2017 | Earth Sciences

Filling the gap: High-latitude volcanic eruptions also have global impact

20.11.2017 | Earth Sciences

Water world

20.11.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>