Sugar Daddy: Not so boron after all

Posted on 09 Feb 2009 by Catherine Goodman

Posted on behalf of Sugar Daddy

With the changing of the guard in Washington, late-night night television hasn’t quite been the same. I guess the new guy in charge is a harder target for comics. Anyway, to a certain extent, the late-night hosts have been turning their attention elsewhere, and eventually chemistry was bound to make it. In this clip, Conan O’Brien draws attention to, among other things, the discovery of a fourth form of pure elemental boron.

The humor in the clip originates from a recent New York Times article that had mistakenly counted the number of pure forms of boron, and Conan was mocking them for not being able to correctly count to four. The surprise for me was that Conan whipped out a big poster board with crystal structures of the various forms of boron and then started to describe them in rather gory scientific detail. I don’t think this will help the public understand chemistry any better, but it’s better than nothing, I guess. Plus, he’s funny.

NChem Research Highlights: Catalysis, catenanes and qubits

Posted on 09 Feb 2009 by Neil Withers

Let’s dive straight in: Catalysts’ performances can be tuned by including other metals – for example, a CuPt alloy. You might expect that, for an effective catalyst, the surface would feature more of the reactive metal – in this case, Pt. But no! The less reactive Cu atoms migrate to the surface, where they create islands of Pt atoms to do the biz with the CO molecules.

Catenanes are molecules of interlocked rings and are normally made by interlocking rings containing either pi-donor or -acceptor groups. What Jeremy Sanders and colleagues have done is put pi-donors AND -acceptors into both rings. The building blocks link together with a donor-acceptor-donor-acceptor pi-section.

One day, we’ll all be using quantum computers. But to get to that exciting future, we need quantum binary digits – or qubits as they are handily abbreviated to – and to control their entanglement. Now, two Cr7Ni rings have been linked together through a Cu-containing ligand system. This provides three qubits, and their entanglement could be controlled by microwave pulses.

And finally…Gav caught physical chemistry textbook guru Peter Atkins on TV yesterday morning. You may be able to watch on the BBC’s iPlayer here. Not a vast amount of chemistry, admittedly, but most definitely a chemist!

Neil

Neil Withers (Associate Editor, Nature Chemistry)

Chemiotics: The further uses of redundancy

Posted on 09 Feb 2009 by Stuart Cantrill

Posted on behalf of Retread

Remember noncoding DNA? For protein that is. That’s 98% of our genome. It now appears that at least half of our genome is transcribed into RNA. Is this a case of transcription machinery gone wild? One type of RNA made from the 98% is called microRNA (after it is cut from a larger precursor). MicroRNAs are only 21-23 nucleotides long. They aren’t used to make proteins (which would be at most 7 amino acids long anyway). Instead they bind to complementary sequences in messenger RNA by classic Watson-Crick base pairing, and inhibit the translation of the mRNA into protein by the ribosome. So although microRNAs don’t code for proteins, they help determine how much of them are made.

Until recently, microRNA binding to mRNA was thought to occur at the tail end (which does not code for protein). Two recent papers show that microRNAs also bind to the amino acid coding sequences of some proteins [Nature vol. 455 pp. 1124-1128, 2008 and PNAS vol. 105 pp. 20297-20302, 2008]. Change one synonymous codon to another, and the microRNA no longer binds and the level of the protein changes. So this is the third code written into our DNA.

What’s so remarkable about that? Pop a DVD of a movie into a player. You are given choices of subtitles, language, etc… All these modalities are coded on separate tracks and blended together by the player after you choose. DNA is just one track and is coding for subtitles, sound and pictures by the same sequence of nucleotides. A given DNA sequence is capable of being read at least 3 ways — amino acid, exonic splicing enhancers and inhibitors, and microRNA — (and who’s to say that these are the only ways DNA can be read).

The examples in the Nature paper are far from trivial as they involve Nanog, Sox2 and Oct4. So what? These three genes are crucial for stem cell function, and with a fourth have been used to transform normal cells into ‘stemlike’ cells (induced pluripotent cells — iPSs). What could be sexier than that? MicroRNA-control of these proteins has to be important.

There has recently been a good deal of interest in diversity oriented synthesis of small molecules — see [Nature vol. 457 pp. 153-154, 2009] and the ‘In the Pipeline’ blog post of 20 Jan, along with the more than 40 comments it brought forth. The hope is to create a wider variety of small molecules which can interact with proteins than we’ve been used to — and which might be useful drugs.

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Reactions – Lynn Loo

Posted on 06 Feb 2009 by Neil Withers

1. What made you want to be a chemist?

I’m still a chemist wanna-be! I’m a chemical engineer by training and I work closely with several chemistry collaborators. The precision of chemistry amazes me. I am always in awe how my collaborators can derivatize and functionalize organic compounds as prescribed with such ease.

2. If you weren’t a chemist and could do any other job, what would it be – and why?

I would like to be a science show/documentary host with PBS or the equivalent. I was always told that I connect with my audience. I think I would really enjoy engaging the public with what we do.

3. How can chemists best contribute to the world at large?

Given the interdisciplinary nature of research today, I believe that we have to reach to work with scientists and engineers in other disciplines to really contribute to the world at large. Underlying the energy challenge today, for example, is the need for the development of new materials as renewable energy sources. Chemists are uniquely equipped to tackle this task. But to really contribute towards solving the world’s energy challenge, we will have to engage researchers in other disciplines, be it to scale up production, or to incorporate these new materials into functional devices.

4. Which historical figure would you most like to have dinner with – and why?

He’s by no means a historical figure but, if granted the opportunity, I would love to have dinner with Bill Nye, the science guy. His love and curiosity for science is infectious! And he inspired me as a child.

5. When was the last time you did an experiment in the lab – and what was it?

Yesterday! I was running some near-edge X-ray absorption fine structure spectroscopy experiments at a soft X-ray beamline at the National Synchrotron Light Source at Brookhaven National Labs. Long hours – but I really enjoy being involved in the experiments.

6. If exiled on a desert island, what one book and one CD would you take with you?

Book – Maria Shriver’s Ten Things I Wish I’d Known Before I Went into the Real World. This book grounds me and provides perspective whenever I am stressed out. I think I would be quite stressed out stranded on an island!

CD – Carla Bruni’s Quelqu’un m’a dit

Lynn Loo is in the Department of Chemical Engineering at Princeton University, and works on the development of plastic transistors and organic solar cells

NChem Research Highlights: Polymers, magnets and suprabowls

Posted on 03 Feb 2009 by Neil Withers

With most of the UK enduring or enjoying a couple of inches of snow, normal Research Highlight service is resumed.

As we’ve known since The Graduate, polymers are the future – especially ones that conduct. But the way that electrons (or excitons to be a bit more accurate) move along polymer chains has always been assumed to be by ‘hopping’ between excited areas. It turns out that they might move more smoothly [the Perspective even says ‘surfing’] and even retain some ‘coherence’.

Metals from the d- and f-blocks are generally pretty different: directional bonding vs diffuse, a range of oxidation states vs stick-in-the-mud 3+, and so on. Compounds that have a metal from both families, therefore, can be pretty interesting – especially magnetically. And that’s just the case for some copper-lanthanide complexes that are (sort of) a trimer of dimers.

Apparently, there was some sort of big sports game thing on Sunday, and it meant Steve could get away with using the word ‘suprabowl’ in his headline. Topical. Anyway, back to the science. The bowls in question are tris(spiroborate)s that form supramolecular polymers with iridium complexes – at room temperature.

And finally…two links that could help improve the way publishing works. One is hosted by the RSC on behalf of a UK funding body (JISC) to understand how you communicate and use information. The other one is to help categorize the comments on PLoS ONE papers. Do your bit for Science 2.0!