Slashdot Mirror

← Back to Stories (view on slashdot.org)

New Amino Acid Discovered

Posted by timothy on from the lookie-here-fellas-it's-another-one dept.

EricMargel writes: "As published in Science, researchers at the Ohio State University claim to have discovered the 22nd known amino acid, pyrrolysine, the first discovered since 1986." I hope rice and beans are still sufficient to get all the needed amino acids.

6 of 142 comments (clear)

  1. And plenty of code space for more. by Rhinobird · · Score: 3, Interesting

    If I remember my high school biology correctly, there are 4 nucleotides, and it take 3 of them to encode an amino acid, basic math...4*4*4=64. We earthlings aren't even using half the code space provided by our current DNA system. Just 1 more and we're there at half.

    --
    If Mr. Edison had thought smarter he wouldn't sweat as much. --Nikola Tesla
  2. Re:These scientists need to work on... by BadDoggie · · Score: 4, Interesting
    Umm.. hello?

    Beano is the magic pill. Alpha-galactose. True, it's an enzyme, not a protein, but a protein isn't going to stop farts, which are mainly caused by sugars we can't digest but which the bugs in our intestines can.

    woof.

  3. Importance of this discovery? by donnacha · · Score: 5, Interesting


    The very fact that this amino acid was overlooked for so long suggests that it's direct importance to our lives is negligible; it's relevance is more about filling the final gaps in an overall picture.

    In the article, Krzycki suggests that it also alters the way we should approach genetics:

    "This shows us that the genetic code, and therefore, evolution is much more plastic than people might have thought."

    "I think this work will cause researchers to start looking at genetic sequences that they might have thought at first were simply aberrations," he said. "Instead, they might signal discoveries like ours."

    1. Re:Importance of this discovery? by rgmoore · · Score: 3, Interesting
      "This shows us that the genetic code, and therefore, evolution is much more plastic than people might have thought."

      "I think this work will cause researchers to start looking at genetic sequences that they might have thought at first were simply aberrations," he said. "Instead, they might signal discoveries like ours."

      Or maybe people already know that. It's already well established that different organisms use different translation tables when synthesizing proteins. The NCBI lists 17 such tables in their section on gene transltation. Heck, the human nucleus and mitochondria use different translatation tables! Is it really such a surprise that those differences might occasionally include an additional amino acid?

      --

      There's no point in questioning authority if you aren't going to listen to the answers.

  4. genetic code non-universal by BlueboyX · · Score: 4, Interesting

    Oddities in the genetic codes of different species have been observed before. While all known life froms have very similar genetic codes (this codon yields that amino acid) there have been some life forms that are exceptions. Several kinds of bacteria express a different amino acid for a specific codon than, say, a human cell would.

    So finding a bacteria like what this artical describes is only a mild suprise.

    Great detective work though. Alot of people would have decided it was alot easier to call this an abberation than to spend ~2 years finding out what was really going on.

    --
    "Never, never suspect the dreams within the dreams of dreaming children." ~The Amazon Quartet
  5. This suggests another regulatory pathway as well. by Gumber · · Score: 3, Interesting

    This "new amino acid" is coded for by a triplet that formerly was only observed to be a stop codon. That is, when the translation machinery came upon the base sequence on the RNA it was reading to build the peptide chain, it ended the chain.

    Now consider this. What if the cell produced the matching tRNA and associated "new amino acid" only intermittantly. When it was available, this stop-codon wouldn't be a stop codon at all and translation would continue, but when it was missing, translation would stop.

    This raises another interesting question (that may already be answered). Some organisms can not synthesize all the amino acids and must obtain some of them from dietary sources. These amino acids are referred to as the essential amino acids for that organism. If their diet is deficient in these essential amino acids, they can't make all the proteins they need, and bad things generally happen.

    So, the question is, what happens at a translational level in this situation? Does translation just stop, leaving shorter peptide chains? Are their situations where the products of partial translation have biological activity?