Tag Archives: Protein

Podcasts

Ann Gauger’s new peer-reviewed paper on Darwinian evolution

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Amazing new research paper by the Biologic Institute. The PDF of the paper, “Reductive Evolution Can Prevent Populations from Taking Simple Adaptive Paths to High Fitness,” is available here.

The MP3 file is here.

Participants

  • Jay Richards, Director of Research at the CRSC, (Discovery Institute)
  • Ann Gauger, senior research scientist at the Biologic Institute

About Ann:

Ann is a senior research scientist at Biologic Institute. Her work uses molecular genetics and genomic engineering to study the origin, organization and operation of metabolic pathways. She received a BS in biology from MIT, and a PhD in developmental biology from the University of Washington, where she studied cell adhesion molecules involved in Drosophila embryogenesis. As a post-doctoral fellow at Harvard she cloned and characterized the Drosophila kinesin light chain. Her research has been published in Nature, Development, and the Journal of Biological Chemistry.

Topics:

  • Co-authored with microbiologist Ralph Seelke at the University of Wisconsion
  • Purpose: study whether bacteria can evolve the ability to fix a broken protein (e.g. – enzyme)
  • Two areas are broken in the enzyme
  • If you fix the first one, it works a little but not fully (slight advantage)
  • If you fix the second one, it starts to work fully (huge advantage)
  • It’s a “two-step adaptive path” – a textbook case for evolution
  • should be able to hit both mutations and get back full functionality
  • At the start of the experiment, the cell is churning out broken protein
  • there is a cost to the cell for create the broken protein
  • the cell can either go through the adaptive path and repair the protein
  • OR, it can shut off production of the broken protein
  • EITHER PATH gives a selective advantage
  • So what happens? The cells NEVER followed the adaptive path
  • They almost ALWAYS turn off the production of the broken protein
  • It happens in 30-50 generations, in 14 different cultures
  • Each culture had a different way of turning off the production
  • They tested on 10^12 cells
  • Only one cell made the first repair, none made the second repair
  • It’s more advantageous to STOP PRODUCING the broken protein as soon as possible
  • The first cell that gets rid of the non-functional protein first overtakes the whole culture
  • so, even adaptive paths that provide a benefit with one mutation are unlikely to be followed
  • The point: even promising theoretical adaptive pathways MAY NOT WORK in experiments

I wrote about Doug Axe’s recent research paper here. He is the Director of the Biologic Institute.

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Podcasts

Doug Axe publishes a new peer-reviewed paper on protein folding

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A new podcast from ID the Future is worth listening to.

Participants

  • Jay Richards, Director of Research at the CRSC, (Discovery Institute)
  • Doug Axe, Director of the Biologic Institute

The MP3 file is here.

Topics

  • the new BIO-Complexity peer-reviewed journal
  • new peer-reviewed paper challenges Darwinian account of protein folding
  • proteins are found in every living system
  • a protein is a chain of parts called amino acids
  • there are 20 amino acids used in living systems
  • it’s like a 20-letter alphabet used to make sentences (proteins)
  • if the sequence is just right, it folds up and has a function
  • the information about the functional sequences is in the genome
  • the “protein fold” is the 3D shape that a functional protein takes on
  • the folding problem is good because you can TEST Darwinian mechanisms
  • the problem is simple enough to be tested rigorously in a lab
  • Question: how easy is it to create a sequence that folds?
  • English is a good analogy to the problem of protein folding
  • you have a long string of characters (e.g. – 200 letters)
  • each “letter” can be one of 20 amino acids
  • if you assign the letters randomly, you almost always get gibberish
  • there are tons of possible sequences of different letters
  • it’s like a 200 digit slot machine with each digit having 20 possibilities!
  • the number of sequences that would actually make sense is tiny
  • protein folding is the same
  • Doug’s paper assesses how many “tries” could have been attempted
  • Doug’s paper calculates the total number of possibilities
  • cells have arrived a large number of functional sequences
  • but only a small number of the total possibilities could have been tried
  • this is called the “sampling problem”
  • there isn’t enough time to test all of the possibilities (see previous paper below)
  • how did living systems arrive at the functional sequences so quickly?
  • there are some possible naturalistic scenarios for solving the problem
  • Doug’s new paper shows that none of the naturalistic explanations work
  • the only explanation left is that an intelligence sequenced the amino acids
  • it is identical to the way that I can sequence letters to make this post

A picture is worth a thousand words

Here’s a video clip from the DVD Darwin’s Dilemma showing the process:

If you would like to know more about Darwin’s Dilemma, you can read Brian Auten’s review of Darwin’s Dilemma.

Who are these guys?

I wrote a post before on Doug Axe’s previous publications in the Journal of Molecular Biology, where he researched how many of the possible sequences of amino acids have biological function. His PhD is from Caltech, and his post-doctoral research on proteins was conducted at Cambridge University.

Jay Richards is a Senior Fellow of the Discovery Institute and a Contributing Editor of The American at the American Enterprise Institute. In recent years he has been a Visiting Fellow at the Heritage Foundation, and a Research Fellow and Director of Acton Media at the Acton Institute. His PhD is from Princeton University.

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News

New study shows that human and chimpanzee DNA are very different

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And this new study is from Nature, the prestigious peer-reviewed journal. (H/T Evolution News via Neil Simpson’s latest round-up)

Excerpt:

A Nature paper from January, 2010 titled, “Chimpanzee and human Y chromosomes are remarkably divergent in structure and gene content,” found that Y chromosomes in humans and chimps “differ radically in sequence structure and gene content,” showing “extraordinary divergence” where “wholesale renovation is the paramount theme.” Of course, the paper attributes these dramatic genetic changes to “rapid evolution during the past 6 million years.”

One of the scientists behind the study was quoted in a Nature news article stating, “It looks like there’s been a dramatic renovation or reinvention of the Y chromosome in the chimpanzee and human lineages.” The news article states that “many of the stark changes between the chimp and human Y chromosomes are due to gene loss in the chimp and gene gain in the human” since “the chimp Y chromosome has only two-thirds as many distinct genes or gene families as the human Y chromosome and only 47% as many protein-coding elements as humans.” According to the news piece, “Even more striking than the gene loss is the rearrangement of large portions of the chromosome. More than 30% of the chimp Y chromosome lacks an alignable counterpart on the human Y chromosome, and vice versa, whereas this is true for less than 2% of the remainder of the genome.”

I’m sure this will make it into the public school textbooks and PBS/Discovery Channel documentaries right away. Right! Away!