Scientists Engineer E.Coli to Produce Key Precursor of Spandex

Scientists Engineer E.Coli to Produce Key Precursor of Spandex

The Future: Bacteria Produced Hot Pants?

Scientists from the company Genomica have genetically engineered E.Coli to produce 1,4-Butanediol (BDO), a key chemical in the production of Spandex, clothing of choice for superheroes, glam rockers and 80’s disco enthusiasts.

The work, published in the journal Nature Chemical Biology, has the potential to drastically change the way BDO is produced. Currently one million metric tons are produced per year and all of this is derived from oil and natural gas. Almost half of the BDO produced globally is dehydrated to produce Tetrahydrofuran. This can then be polymerised to polytetramethylene oxide, the primary use of which is in fibres such as spandex.

The researchers faced several challenges whilst trying to produce their engineered bacteria. The first of which being identifying a synthesis mechanism, as there is no known naturally occurring biological synthesis pathway for BDO. Instead they had to compute all potential pathways from the typical E. coli metabolites to BDO. The computer algorithm they used  identified over 10,000 four-six step pathways that could result in synthesis of BDO from common metabolites, including acetyl-CoA, succinyl-CoA and glutamate.

These methods were then narrowed down based on theoretical yield, pathway length and thermodynamic feasibility. After this they picked out the following pathway as the best way for E.Coli to produce BDO:

The BDO synthesis pathway. Each number indicates an enzyme: (1) 2-oxoglutarate decarboxylase; (2) succinyl-CoA synthetase; (3) CoA-dependent succinate semialdehyde dehydrogenase; (4) 4-hydroxybutyrate dehydrogenase; (5) 4-hydroxybutyryl-CoA transferase; (6) 4-hydroxybutyryl-CoA reductase; (7) alcohol dehydrogenase. Steps 2 and 7 occur naturally in E. coli, whereas the others are encoded by heterologous genes introduced in this work.

With an elucidated pathway, then came the challenge of how to get a bacterium to carry it out. Not all the enzymes required for the pathway are present in the wildtype E.Coli. As a result of this, the group identified several different mechanisms for generating the intermediate 4-Hydroxybulymate (4HB) settling on; the addition of three genes sucCD (E. coli), sucD and 4hbd (P. gingivalis).

The final stage in the process, 4HB to BDO, also required some manipulation. The change requires two reduction steps, catalyzed by dehydrogenases. This can occur by the addition of exogenous 4HB to wild-type Clostridium acetobutylicum. However, for efficient production they needed to have the process contained within E.Coli. So instead  they expressed the 4-hydroxybutyryl-CoA transferase (cat2) gene from P. gingivalis for the conversion of 4HB to 4HB-CoA. The final stages then involved the action of  4-hydroxybutyryl-CoA reductase and the native alcohol dehydrogenase, finally resulting in a viable BDO product.

Whilst this discovery does not directly result in the production of spandex or other useful fibres by bacteria. This could prove to be an efficient and environmentally friendly way to produce crime-fighting and disco outfits at some point in the future!

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And the Oscar goes to…Science!?

And the Oscar goes to…Science!?

"I'd just like to thank my project supervisor..."

Hollywood has never had a particularly good reputation for scientific accuracy. However, recently its science acumen has received a boost. It is currently the first time that the ‘reigning’ best actor and actress have been both been scientifically published.

Colin Firth, has taken time out from swimming in country lakes and stuttering to co-author a paper in Current Biology. The research looked into whether there are any structural differences in the brains of young adults with different political affiliations.

His co-Oscar winner Natalie Portman has been published twice. Credited as Natalie Hershlag, her family name, she published a paper on sugar chemistry whilst in high school and another entitled “Frontal Lobe Activation during Object Permanence: Data from Near-Infrared Spectroscopy” whilst completing her psychology degree at Harvard.

Figure 1. Individual Differences in Political Attitudes and Brain Structure

Both also seem to have made valuable contributions to scientific knowledge with their research. Firth’s paper showed that “Liberalism was associated with the gray matter volume of anterior cingulate cortex” and that “Conservatism was associated with increased right amygdala size” as can been seen in Figure 1.

The question of whether or not it is psychological or environmental factors that influence political stance has been debated for many years. The findings of the paper side with recent studies in twins which claims that “a substantial amount” of political opinion is influenced by genetics.

The neuroscience paper published by Natalie Portman looked into the progress of ‘object permanence’ in child development. Object permanence is the understanding that objects continue to exist even when they cannot be seen, heard, or touched. Her research used near-infrared spectroscopy to monitor the levels of oxy and deoxyhaemoglobin. The research revealed that the rise in object permanence occurs simultaneously to a rise in the levels of haemoglobin concentration in the frontal cortex.

Whilst, these two members of the Hollywood A-list have dabbled in a bit of science it seems that they aren’t going to give up on their day jobs. Portman most recently graced our screens in the decidedly unscientific Thor, whilst Colin Firth was most recently seen in the tense spy film “Tinker, Tailor, Soldier, Spy”.

Back to the Science Future

Back to the Science Future

Where is my jet pack? Why can’t I live forever yet? And where is my Technological apocalypse?

Friday saw the launch of the new issue of I’Science magazine. It has been entitled the “Great Expectations” issue. It looked at what science has promised us in the past and how close we are to full filling those predictions. You can check it out here.

 To celebrate the release of the issue I am going to share an art project which I happened across a few weeks ago.  It is a set of prophetic illustrations by the French artist Villemard. He produced them in 1910, intending to show what life would be like in the year 2000. Some of his predictions are remarkably accurate and others are just plain odd.

 

1)

Prediction: Appears to be a primitive version of video calling

Exists in the 21st Century: Yes, and has been around in various forms for decades.

2)

Prediction: Flying cars and flight suits

Exists in the 21st Century: No, although not from lack of trying 

3)

Prediction: Computer aided design

Exists in the 21st Century: Yes, and with the rise of the 3D printer only likely to become more prevalent and publicly available.

4)

Prediction: A Matrix-esque method of learning

Exists in the 21st Century: No, still only in science fiction. Although it could be argued that this is image is an allegory for Wikipedia.

5)

Prediction: A sort of boat, airship crossbreed

Exists in the 21st Century: No, I’m pretty sure these don’t exist! 

6)

Prediction: An automated hairdressers

Exists in the 21st Century: No, the closest we have come to this prediction is the electric razor.

7)

Prediction: Automatic Make-up

Exists in the 21st Century: No, although versions of this can be seen in the Fifth Element and The Simpsons.

8 )

Prediction: Electric roller skates

Exists in the 21st Century: These do exist

Reiki is practiced in an NHS breast cancer ward

Reiki is practiced in an NHS breast cancer ward

 

Reiki treatment involves no physical contact

In the foothills of Mount Kurama a man meditates. He has been there for 21 days. Suddenly, he has a revelation.

From this quiet beginning in 1922 the practice of reiki was born. Since then, it has evolved and found itself keeping company with treatments such as homeopathy and acupuncture in modern complementary medicine. The practice of reiki involves the practitioner transferring healing energy, or ‘ki’, to the subject through their palms. Those who support the treatments claim that this can help a wide range of conditions, including depression and anxiety as well as improving immunity. Contrary to these claims, reiki and other complementary medicines have been widely studied and the scientific consensus is that they have minimal, if any, clinical benefits. Despite this, reiki and its allied medicines are, shockingly, still afforded a place in the medical treatment establishment.

This acceptance of alternative medicine can be seen specifically at The Princess Alexandra Hospital NHS Trust, Essex, where they employ a “Reiki Therapist/Spiritual Healer”  in a breast cancer ward. The position is funded by an alternative medicine charity, but its location within an NHS hospital has drawn criticism. Professor Edzard Ernst, the world’s first, and only, professor of complementary medicine said, “We have published a systematic review of reiki…the evidence is simply not there. There are a number of studies, they are flimsy and the ones that are rigorous don’t generate a positive result. In my book the evidence is even negative,” he added.

The way in which this post has been advertised raises some serious questions about the medical validity of the job. The criteria state that the practitioner must “demonstrate the benefit and activity of the post”. Philippa Dooher, Lead Breast Care Specialist Nurse and supervisor of the position, outlined how this is judged: “Before and after treatment the practitioner engages in a core evaluation of how the patient is feeling. There is also the option for patient feedback.”   Considering the analysis of medical benefits of the treatment, she admitted that the success of the post is “not based on the effect on prognosis”. This stance is problematic according to Professor Ernst who described the attempts to justify the job as “ridiculously funny”.

Thankfully, it appears that this practice is not common in the NHS. Professor Ernst commented that the post seemed “exceptional”. But, he went on to add that outside of the National Health Service “…the use of alternative medicine in Britain is fairly widespread. About 20% of the general population use these treatments; with cancer patients the percentage is much higher.”   Dooher agreed with this, saying that the only alternative practitioners in the hospital were the reiki therapist, and a reflexologist on the same breast cancer ward.

The role in the hospital has been occupied for a year. The way through which patients are recruited to the scheme is another interesting addition to this tale. As well as being given forms to apply for treatment, the patients are approached in the waiting room and offered reiki by the practitioner themselves.

It seems highly illogical that an institution that should make decisions based on evidence and critical observation offers this therapy on an oncology ward. This is a view also expressed by Professor Ernst, who said that it is “Truly, truly embarrassing that an NHS trust should advertise for a reiki healer … [the position] discloses a total lack of critical regard to what they are doing, and I think it’s ridiculous, dangerous, and undermines everything that evidence based medicine and rationality stands for.”

Whilst the creation of reiki in the mountainous regions of Japan may be a nice story, it is disconcerting that almost one hundred years later “spiritual healing energy” can still be found within the NHS. 

Update

This article was inspired by a job advertisement posted by the PAH Trust, upon discussion it was revealed that the post had been filled for a year and since my conversation with the hospital the advertisement has been removed from their website.

ResearchBlogging.org

Lee MS, Pittler MH, & Ernst E (2008). Effects of reiki in clinical practice: a systematic review of randomised clinical trials. International journal of clinical practice, 62 (6), 947-54 PMID: 18410352

A new science writing adventure begins…

A new science writing adventure begins…

In a recent post I spoke about the new online collaborative science magasine, Guru. Well I’m happy to say that I am their new ‘Technology Guru’. You can check out the article about me joining the team here. I am currently working on my first article for them and whilst I will not reveal what it is about this photo from a fancy dress party a few years ago will give a little clue:

Also another bit of update info is that this site is currently undergoing a complete re-design and will soon emerge from its cocoon looking a lot prettier with more frequent posting

 

Viral Science: The “Most Beautiful” Science Experiment

Viral Science: The “Most Beautiful” Science Experiment

I often think that science doesn’t fully take advantage of what can be achieved with the viral video platform. However, this video by NatSciDemos has succeeded in going well and truly  viral and has achieved over 2.3 million views. Professor Richard Wiseman described it as one of “the most beautiful videos”. Check it out and prepare to be memorised:

What do you think, is there a more visually stunning experiment? If so drop me a comment below, would be cool to generate a bit of a list of beauty within science.

Check it out here

Scientists show the evolution of the Amphitheatre

Scientists show the evolution of the Amphitheatre

This post was chosen as an Editor's Selection for ResearchBlogging.org

Back before the internet, twitter and megaphones it was a great deal more difficult to get your voice heard. However, those clever Greeks and Romans had a way of using the science of acoustics to get their message out.

They constructed great amphitheatres which seated thousands. An example of which is the image below I took when exploring an ancient Roman site in rural Turkey.

Click for High Def version

Scientists have continued to do research the way the acoustics worked to propel the voice of those ‘on stage’. A study by K. Chourmouziadou & J. Kang, published in the Journal of Applied Acoustics showed that amphitheatres evolved and changes in materials as well as design resulted in acoustic improvements. They simulated 6 different theatre types: Minoan, Pre-Aeschylean, Early Classic, Classic, Hellenistic and Roman.  Each of these had different characteristics (figure 1)

Figure 1: A breakdown of the different theatre types

Figure 2: Over time the amount of reverberation in an occupied theatre is seen to increase

The researchers then used acoustic simulation software to examine the theaters. They monitored the absorption and scattering conditions in each incarnation of the theatre. Their results indicated that there was increased reverberation time as the theatres evolved (figure 2) and the speech transmission increased in occupied theatres. They concluded that overall the evolution of the theatres brought about an improved listening experience.

ResearchBlogging.org
CHOURMOUZIADOU, K., & KANG, J. (2008). Acoustic evolution of ancient Greek and Roman theatres Applied Acoustics, 69 (6), 514-529 DOI: 10.1016/j.apacoust.2006.12.009