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Posts tagged with "Life As We (Don’t) Know It"

  • Biological News

    Artificial Base Pairs in Living Cells

    Synthetic biology seems to have taken another big step. Many labs over the years have tried out expanding the genetic code in various ways, but all these run in various in vitro systems. Now the first organism has been engineered with a working unnatural base pair, according to this paper in Nature from the Romesburg… Read More
  • Chemical News

    Thermodynamics of Life

    Origin-of-life studies have been a feature of chemistry for a long time, and over the years some key questions have become clear. It’s clear from astronomical and planetary science data that the common molecules of organic chemistry are more or less soaking the universe. Amino acids and simple carbohydrates are apparently part of the cloud… Read More
  • Life As We (Don't) Know It

    Hybrid Biomolecules, Edible And Not

    While writing up that eight-toxic-foods rebuttal the other day, I started reading up on Olestra, the “fake fat” that made the list. While it has to be considered a failure for its developers, I found the chemistry behind it interesting, and it got me to thinking. First off, for those outside the chemical/biochemical field, a… Read More
  • Biological News

    How Many Binding Pockets Are There?

    Just how many different small-molecule binding sites are there? That’s the subject of this new paper in PNAS, from Jeffrey Skolnick and Mu Gao at Georgia Tech, which several people have sent along to me in the last couple of days. This question has a lot of bearing on questions of protein evolution. The paper’s… Read More
  • Chemical News

    The Galaxy Is Full of Gunk

    We’ll start off with a little extraterrestrial chemistry. As many will have heard, there are all sorts of hints being dropped that the sample analyzing equipment on the Mars Curiosity rover has detected something very interesting. We’ll have to wait until the first week of December to find out what it is, but my money… Read More
  • Life As We (Don't) Know It

    Arsenic Life No More

    The “arsenic life” bacterium has taken a number of blows in the scientific literature, and now it’s taken another. A close look at its phosphate uptake system shows that these proteins in the GFAJ-1 bacteria not selective for arsenate (or at least tolerant of it, compared to normal lines). They are, in fact, extremely selective… Read More
  • Life As We (Don't) Know It

    The Redfield Paper Is Out (And So Are Arsenic Bacteria, It Seems)

    Via Curious Wavefunction comes the news that Rosie Redfield and her lab have their paper coming out in Science refuting the “arsenic bacteria” results. It should be out on the journal’s web site shortly, but is available at Arxiv beforehand. I’ve been following Redfield’s blogged results over the last few months, on an… Read More
  • Life As We (Don't) Know It

    Arsenic Bacteria Ride Again. (Or Don’t).

    You may not have heard much about the arsenic-bacteria controversy recently, but you’re about to hear quite a bit more. Rosie Redfield of UBC, one of the fastest and most vocal critics of the original paper, has been trying to reproduce it in her own group. There’s a manuscript in preparation, but since she’s been… Read More
  • Biological News

    A First Step Toward A New Form of Life

    There’s been a real advance in the field of engineered “unnatural life”, but it hasn’t produced one-hundredth the headlines that the arsenic bacteria story did. This work is a lot more solid, although it’s hard to summarize in a snappy way. Everyone knows about the four bases of DNA (A, T, C, G). What this… Read More
  • Life As We (Don't) Know It

    Arsenic in DNA: The Kinetic Argument.

    Here’s the first response in the chemical literature to the arsenic-in-DNA controversy, from three authors in ACS Chemical Biology. They detail the argument, familiar to readers of the comment section here, that arsenate esters just would not be expected to have the hydrolytic stability needed for arseno-DNA to function usefully. How far off… Read More