Tag Archives: Amino Acid

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Stephen C. Meyer lectures on intelligent design and the origin of life

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A MUST-SEE lecture based on Dr. Stephen C. Meyer’s book “Signature in the Cell“.

You can get an MP3 of the lecture here. (30 MB)

I highly recommend watching the lecture, and looking at the slides. The quality of the video and the content is first class. There is some Q&A (9 minutes) at the end of the lecture.

Topics:

  • intelligent design is concerned with measuring the information-creating capabilities of natural forces like mutation and selection
  • Darwinists think that random mutations and natural selection can explain the origin and diversification of living systems
  • Darwinian mechanisms are capable of explaining small-scale adaptive changes within types of organisms
  • but there is skepticism, even among naturalists, that Darwinian mechanisms can explain the origin of animal designs
  • even if you concede that Darwinism can account for all of the basic animal body plans, there is still the problem of life’s origin
  • can Darwinian mechanisms explain the origin of the first life? Is there a good naturalistic hypothesis to explain it?
  • there are at least two places in the history of life where new information is needed: origin of life, and Cambrian explosion
  • overview of the structure of DNA and protein synthesis (he has helpful pictures and he uses the snap lock blocks, too)
  • the DNA molecule is composed of a sequence of bases that code for proteins, and the sequence is carefully selected to have biological function
  • meaningful sequences of things like computer code, English sentences, etc. require an adequate cause
  • it is very hard to arrive at a meaningful sequence of a non-trivial length by randomly picking symbols/letters
  • although any random sequence of letters is improbable, the vast majority of sequences are gibberish/non-compiling code
  • similarly, most random sequences of amino acids are lab-proven (Doug Axe’s work) to be non-functional gibberish
  • the research showing this was conducted at Cambridge University and published in the Journal of Molecular Biology
  • so, random mutation cannot explain the origin of the first living cell
  • however, even natural selection coupled with random mutation cannot explain the first living cell
  • there must already be replication in order for mutation and selection to work, so they can’t explain the first replicator
  • but the origin of life is the origin of the first replicator – there is no replication prior to the first replicator
  • the information in the first replicator cannot be explained by law, such as by chemical bonding affinities
  • the amino acids are attached like magnetic letters on a refrigerator
  • the magnetic force sticks the letters ON the fridge, but they don’t determine the specific sequence of the letters
  • if laws did determine the sequence of letters, then the sequences would be repetitive
  • the three materialist explanations – chance alone, chance and law, law alone – are not adequate to explain the effect
  • the best explanation is that an intelligent cause is responsible for the biological explanation in the first replicator
  • we know that intelligent causes can produce functional sequences of information, e.g. – English, Java code
  • the structure and design of DNA matches up nicely with the design patterns used by software engineers (like WK!)

There are some very good tips in this lecture so that you will be able to explain intelligent design to others in simple ways, using everyday household items and children’s toys to symbolize the amino acids, proteins, sugar phosphate backbones, etc.

Proteins are constructed from a sequence of amino acids:

A sequence of amino acids forming a protein
A sequence of amino acids forming a protein

Proteins sticking onto the double helix structure of DNA:

Some proteins sticking onto the sugar phosphate backbone
Some proteins sticking onto the sugar phosphate backbone

I highly, highly recommend this lecture. You will be delighted and you will learn something.

Here is an article that gives a general overview of how intelligent design challenges. If you want to read something more detailed about the material that he is covering in the lecture above related to the origin of life, there is a pretty good article here.

There is a good breakdown of some of the slides with helpful flow charts here on Uncommon Descent.

Positive arguments for Christian theism

Polemics

New software calculates the probability of generating functional proteins by chance

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Apologetics and the progress of science
Apologetics and the progress of science

Here’s an article sent to me by JoeCoder about a new computer program written by Kirk Durston.

About Kirk:

Kirk Durston is a scientist, a philosopher, and a clergyman with a Ph.D. in Biophysics, an M.A. in Philosophy, a B.Sc. in Mechanical Engineering, and a B.Sc. in Physics. His work involves a significant amount of time thinking, writing and speaking about the interaction of science, theology and philosophy within the context of authentic Christianity. He has been married for 34 years to Patti and they have six children and three grandchildren. He enjoys landscape photography, antiques of various types, wilderness canoeing and camping, fly fishing, amateur astronomy, reading, music, playing the saxophone (alto), and enjoying family and friends.

Kirk grew up on a cattle and grain farm in central Manitoba, Canada, where he spent countless hours wandering around on his own in the forest as a young boy, fascinated with the plants and animals that are native to that region of the province. Throughout his teen years he spent six days a week in the summer working as a farm hand with cattle and grain. He left his father’s farm at the age of 19 to go to university.

Canada? Can anything good come out of Canada? Oh well, at least he’s not from Scotland. Anyway, on to the research, that’s what we care about. Code!

Summary of the article:

  • Biological life requires proteins
  • Proteins are sequences of amino acids, chained together
  • the order of amino acids determines whether the sequence has biological function
  • sequences that have biological function are rare, compared to the total number of possible sequences
  • Durston wrote a program to calculate the number of the probability of getting a functional sequence by random chance
  • The probability for getting a functional protein by chance is incredibly low

With that said, we can understand what he wrote:

This program can compute an upper limit for the probability of obtaining a protein family from a wealth of actual data contained in the Pfam database. The first step computes the lower limit for the functional complexity or functional information required to code for a particular protein family, using a method published by Durston et al. This value for I(Ex) can then be plugged into an equation published by Hazen et al. in order to solve the probability M(Ex)/N of ‘finding’ a functional sequence in a single trial.

I downloaded 3,751 aligned sequences for the Ribosomal S7 domain, part of a universal protein essential for all life. When the data was run through the program, it revealed that the lower limit for the amount of functional information required to code for this domain is 332 Fits (Functional Bits). The extreme upper limit for the number of sequences that might be functional for this domain is around 10^92. In a single trial, the probability of obtaining a sequence that would be functional for the Ribosomal S7 domain is 1 chance in 10^100 … and this is only for a 148 amino acid structural domain, much smaller than an average protein.

For another example, I downloaded 4,986 aligned sequences for the ABC-3 family of proteins and ran it through the program. The results indicate that the probability of obtaining, in a single trial, a functional ABC-3 sequence is around 1 chance in 10^128. This method ignores pairwise and higher order relationships within the sequence that would vastly limit the number of functional sequences by many orders of magnitude, reducing the probability even further by many orders of magnitude – so this gives us a best-case estimate.

There are only about 10^80 particles in the entire physical universe – 10^85 at the most. These are long odds. But maybe if we expand the probabilistic resources by buying more slot machines, and we pull the slot machine lever at much faster rate… can we win the jackpot then?

Nope:

What are the implications of these results, obtained from actual data, for the fundamental prediction of neo-Darwinian theory mentioned above? If we assume 10^30 life forms with a fast replication rate of 30 minutes and a huge genome with a very high mutation rate over a period of 10 billion years, an extreme upper limit for the total number of mutations for all of life’s history would be around 10^43. Unfortunately, a protein domain such as Ribosomal S7 would require a minimum average of 10^100 trials, about 10^57 trials more than the entire theoretical history of life could provide – and this is only for one domain. Forget about ‘finding’ an average sized protein, not to mention thousands.

So even if you have lots of probabilistic resources, and lots of time, you’re still not going to get your protein.

Compare these numbers with the 1 in 10^77 number that I posted about yesterday from Doug Axe. There is just no way to account for proteins if there is no intelligent agent to place the amino acids in sequence. When it comes to writing code, writing blog posts, writing music, or placing Scrabble letters, you need an intelligence. Sequencing amino acids into proteins? You need an intelligence.

Polemics

Was early Earth’s atmosphere suitable for creating the building blocks of life?

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Do the Miller-Urey experiments simulate the early Earth?
The Miller-Urey experiments

Biochemist Dr. Fazale Rana of Reasons to Believe offers some evidence.

Excerpt:

Today, the Miller-Urey experiment is considered to be irrelevant to the origin-of-life question. Current understanding of the composition of early Earth’s atmosphere differs significantly from the gas mix used by Miller. Most planetary scientists now think that the Earth’s primeval atmosphere consisted of carbon dioxide, nitrogen, and water vapor. Laboratory experiments indicate that this gas mixture is incapable of yielding organic materials in Miller-Urey-type experiments.

In May 2003 origin-of-life researchers Jeffrey Bada and Antonio Lazcano, long-time associates of Miller, wrote an essay for Science (May 2, 2003, pp. 745-746)commemorating the 50-year anniversary of the publication of Miller’s initial results.They pointed out that the Miller-Urey experiment has historical significance, but not scientific importance in contemporary origin-of-life thought. Bada and Lazcano wrote:

Is the “prebiotic soup” theory a reasonable explanation for the emergence of life? Contemporary geoscientists tend to doubt that the primitive atmosphere had the highly reducing composition used by Miller in 1953.

In his book Biogenesis, origin-of-life researcher Noam Lahav passes similar judgment:

The prebiotic conditions assumed by Miller and Urey were essentially those of a reducing atmosphere. Under slightly reducing conditions, the Miller-Urey reaction does not produce amino acids, nor does it produce the chemicals that may serve as the predecessors of other important biopolymer building blocks. Thus, by challenging the assumption of a reducing atmosphere, we challenge the very existence of the “prebiotic soup”, with its richness of biologically important organic compounds.

For many people, the generation of amino acids from simple chemical compounds thought to be present in early Earth’s atmosphere meant that life could originate all on its own without the need for a Creator. Work done on the early planetary conditions of Earth in the intervening decades between Miller’s famous experiment and his death, however, have invalidated this famous experiment and its support for an evolutionary explanation for life’s origin, in spite of what textbooks report.

The IDEA Center has a nice summary of origin-of-life research that explains why scientists no longer accept the idea that the building blocks of life can be formed by sparking the gasses that were present on the early Earth.

Miler and Urey used the wrong gasses:

Miller’s experiment requires a reducing methane and ammonia atmosphere, however geochemical evidence says the atmosphere was hydrogen, water, and carbon dioxide (non-reducing). The only amino acid produced in a such an atmosphere is glycine (and only when the hydrogen content is unreasonably high), and could not form the necessary building blocks of life.

Miller and Urey didn’t account for UV of molecular instability:

Not only would UV radiation destroy any molecules that were made, but their own short lifespans would also greatly limit their numbers. For example, at 100ºC (boiling point of water), the half lives of the nucleic acids Adenine and Guanine are 1 year, uracil is 12 years, and cytozine is 19 days (nucleic acids and other important proteins such as chlorophyll and hemoglobin have never been synthesized in origin-of-life type experiments).

Miller and Urey didn’t account for molecular oxygen:

We all have know ozone in the upper atmosphere protects life from harmful UV radiation. However, ozone is composed of oxygen which is the very gas that Stanley Miller-type experiments avoided, for it prevents the synthesis of organic molecules like the ones obtained from the experiments! Pre-biotic synthesis is in a “damned if you do, damned if you don’t” scenario. The chemistry does not work if there is oxygen because the atmosphere would be non-reducing, but if there is no UV-light-blocking oxygen (i.e. ozone – O3) in the atmosphere, the amino acids would be quickly destroyed by extremely high amounts of UV light (which would have been 100 times stronger than today on the early earth).This radiation could destroy methane within a few tens of years, and atmospheric ammonia within 30,000 years.

And there were three other problems too:

At best the processes would likely create a dilute “thin soup,” destroyed by meteorite impacts every 10 million years. This severely limits the time available to create pre-biotic chemicals and allow for the OOL.

Chemically speaking, life uses only “left-handed” (“L”) amino acids and “right-handed” (“R)” genetic molecules. This is called “chirality,” and any account of the origin of life must somehow explain the origin of chirality. Nearly all chemical reactions produce “racemic” mixtures–mixtures with products that are 50% L and 50% R.

Two more problems are not mentioned in the article. A non-peptide bond anywhere in the chain will ruin the chain. You need around 200 amino acids to make a protein. If any of the bonds is not a peptide bond, the chain will not work in a living system. Additionally, the article does not mention the need for the experimenter to intervene in order to prevent interfering cross-reactions that would prevent the amino acids from forming. That’s another problem with the origin of life – experiments show that getting the building blocks requires an intelligence to intervene.

Now keep in mind that even if you get the building blocks, you are left with the sequencing problem – but that’s another topic for another day.