Water, water everywhere—but is it essential to life?

April 13, 2012, University of Bristol

Proteins are large organic molecules that are vital to every living thing, allowing us to convert food into energy, supply oxygen to our blood and muscles, and drive our immune systems. Since proteins evolved in a water-rich environment, it is generally thought that they are dependent on water to survive and function.

Proteins consist of one or more polypeptides – chains of amino acids held together by peptide bonds. If a in water is heated to temperatures approaching the boiling point of water, these chains will lose their structure and the protein will denature (unfold).

A classic example of denaturing occurs when an egg is hard-boiled: the structures of the proteins in the egg unfold with temperature and stick together creating a solid. In the egg's case, this process cannot be reversed – however there are many examples where cooling the protein results in refolding of the structure.

Previously, it was thought that water was essential to the refolding process, however the Bristol findings suggest this isn't necessarily the case.

Using a spectroscopic technique called circular dichroism, Dr Adam Perriman of Bristol's School of Chemistry and colleagues have shown that the oxygen-carrying protein myoglobin can refold in an environment that is almost completely devoid of water molecules.

Dr Perriman said: "We achieved this by attaching polymer molecules to the surface of the protein and then removing the to give a viscous liquid which, when cooled from a temperature as high as 155°C, refolded back to its original structure.

"We then used the Circular Dichroism beamline (B23) at Diamond Light Source, the UK's national synchrotron science facility in Oxfordshire, to track the refolding of the myoglobin structure and were astounded when we became aware of the extremely high thermal resistance of the new material."

These findings could pave the way for the development of new industrial enzymes where hyper-thermal resistance would play a crucial role, in applications ranging from biosensor development to electrochemical reduction of CO2 to liquid fuels.

Explore further: Scientists make water-free liquid from blood protein

More information: 'Hyper-thermal stability and unprecedented re-folding of solvent-free liquid myoglobin' by Alex Brogan, Giuliano Siligardi, Rohanah Hussain, Adam Perriman and Stephen Mann in Chemical Science DOI: 10.1039/C2SC20143G

Related Stories

Scientists make water-free liquid from blood protein

June 7, 2010

(PhysOrg.com) -- Scientists at the University of Bristol have discovered a way to make a highly concentrated water-free liquid of a key blood protein, myoglobin, opening up the possibility of new types of biomedical materials.

Chemists make liquid protein

July 23, 2009

(PhysOrg.com) -- The first known example of a liquid protein has been made by chemists at the University of Bristol opening up the possibility of a number of medical and industrial applications including high-potency pharmaceuticals ...

A new tool to reveal structure of proteins

March 19, 2012

A new method to reveal the structure of proteins could help researchers understand biological molecules – both those involved in causing disease and those performing critical functions in healthy cells.

Engineers squeeze secrets from proteins

March 21, 2006

Proteins, one of the basic components of living things, are among the most studied molecules in biochemistry. Understanding how proteins form or "fold" from sequenced strings of amino acids has long been one of the grand ...

Shoe strings and egg openers

November 8, 2011

Photosynthesis is one of the most important biological processes. However, it is less efficient in plants than it could be. Red algae, in contrast, use a slightly different mechanism and are thus more productive. Scientists ...

Recommended for you

A protein that self-replicates

February 22, 2018

ETH scientists have been able to prove that a protein structure widespread in nature – the amyloid – is theoretically capable of multiplying itself. This makes it a potential predecessor to molecules that are regarded ...

Newly designed molecule binds nitrogen

February 22, 2018

Wheat, millet and maize all need nitrogen to grow. Fertilisers therefore contain large amounts of nitrogenous compounds, which are usually synthesised by converting nitrogen to ammonia in the industrial Haber-Bosch process, ...


Adjust slider to filter visible comments by rank

Display comments: newest first

5 / 5 (1) Apr 13, 2012
Water, water everywhere "& ndash" but is it essential to life?

You guys... really don't do even the most minor kind of checking, do you?
1 / 5 (4) Apr 14, 2012
Since proteins evolved in a water-rich environment,
I should point out that this is a nonsensical, pseudo science statement. The researcher or author of the article has zero supporting evidence that this was the case. Since proteins are essential for life they could not have "evolved". They had to be present already at the start of life. According to the evolutionary theory there can be no natural selection or mutations until life actually exists. Hence: this statement is just plain nonsense.
not rated yet Apr 14, 2012
Proteins are essential for life?

I think we should find some alternate life before we go deciding such things.

5 / 5 (3) Apr 14, 2012
The researcher or author of the article has zero supporting evidence that this was the case -KevinTard

What do you care about evidence? Your god delusion doesn't require it, so why are you asking for it?
not rated yet Apr 14, 2012
Water, water everywhere "& ndash" but is it essential to life?

You guys... really don't do even the most minor kind of checking, do you?

phys.org is probably just a bot that scrapes content from other sites
4 / 5 (1) Apr 14, 2012
I'm afraid I'll have to add a frown to those already expressed about this article.

The headline poses a question, but the article makes no attempt to answer it. The research cited does not answer it, either.

Nor could it. Looking at a specific group of proteins under specific conditions doesn't even scratch the surface of a question as big as "is water essential to life?"

This summary, bluntly, is guilty of hyperbole. I don't know if the paper cited is also guilty of it.
not rated yet Apr 14, 2012
Water may not be required, but chemical life will require a solvent and there are a limited number of those to be found in space, and they are limited to specific temperatures and pressures.

As a practical matter there is only one practical solvent. Water.

Liquid methane probably comes next, but given it's temperature, I don't expect to find enough thermal energy to produce life.

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.