Why the Origin of Life Suggests Design Walter L. Bradley, Ph.D., P.E. Distinguished Professor of Engineering Baylor University.
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Why the Origin of Life Suggests Design
Walter L. Bradley, Ph.D., P.E.
Distinguished Professor of Engineering
Baylor University
Context for this talk
• Origin of universe
• Origin of life
• Origin of great diversity of life
• Origin of homo sapiens (humans)
• Origin of human consciousness
Famous Atheist Now Believes in God, Associated Press, 12/9/2004
• A British philosophy professor who has been a leading champion of atheism for more than a half-century has changed his mind. He now believes in God, more or less based on scientific evidence. Anthony Flew says that biologists’ investigation of DNA “has shown by the almost unbelievable complexity of the arrangements which are needed to produce life that intelligence must have been involved.
What distinguishes living from non-living systems?
All living systems……………….
Process energy
Store information
Replicate
What do these molecular “machines”, or bio-polymers look like?
• Mer = molecule (like links in a chain)• Poly = many (like a chain)• Polymer = many molecules joined in a chain
like arrangement• “Chain links” may be
– All links the same as in garden variety plastics (e.g., polyethylene or PVC)
– Many different links in bio-polymers (e.g., proteins 20 different links called amino acids)
What bio-polymers are necessary for life functions?
• Molecular machinery in form of polymer chains– DNA: stores information and replicates– RNA: transforms DNA information in protein– Protein: provides structures – Protein/enzymes: provides chemical control
through catalytic activity
• These are primary polymers of life.
The characters in our story:
The characters in our story:
Francis Crick James Watson
Lysine
Threonine
Tryptophan
Valine
Serine
Phenylalanine
Tyrosine
Isoleucine
“Now what I find profoundlydisturbing is that I cannot conceiveof any structure (for either nucleicacid) acting as a direct templatefor amino acids, or at least as aspecific template....I don’t thinkanybody looking at DNA or RNAwould think of them as templatesfor amino acids.”
Crick (1955) grasps the difficulty:Crick (1955) grasps the difficulty:
Crick then triangulates to what must be the case from biological necessity:
Crick then triangulates to what must be the case from biological necessity:
“DNA carries information,but is chemically non-specific.”
“Yet amino acids havespecific geometries.”
“Therefore, mediating (‘adaptor’) molecules must exist, toenable specifying information to pass from DNA to amino acids.”
Lysine
Threonine
Tryptophan
Valine
Serine
Phenylalanine
Tyrosine
Isoleucine
“adaptor”
bind tonucleic acid
bind to a specificamino acid
working with aspecial dedicatedenzyme (protein)
And, by the way – we need20 of these molecules, with 20specially dedicated adaptors, or tRNAs: one for each amino acid.
transfer RNAtransfer RNA
Watson (2002, 139) explains why he doubted the adaptor hypothesis:
Watson (2002, 139) explains why he doubted the adaptor hypothesis:
“I did not like the idea at all....More to the point, the adaptor
mechanism seemed to metoo complicated to have everevolved at the origin of life.”
Watson’s biological intuition was constrainedby his materialistic worldview.
Watson’s biological intuition was constrainedby his materialistic worldview.
The functions of a cell are all interrelated:The functions of a cell are all interrelated:
cell division(reproduction)cell division(reproduction)
transporttransport
metabolismmetabolism
informationreplicationinformationreplication
cell wall ormembranecell wall ormembrane
energyconversionenergyconversion
informationstorage andtransfer
informationstorage andtransfer
Top Down Approaches
• Simple bacteria (e.g., E-coli) have DNA with 4,000,000 units of information which is equivalent to a 1000 page book.
• Recent studies of simple organisms suggests the minimum number of proteins required is 250-380.
• The building blocks for 1 protein (cytochrome C) can be arranged 1074 ways that don’t work and only 1 way that does.
Bottom Up Approaches
• How easy is it to make DNA, tRNA, and protein under pre-biotic conditions?
• How can these be assembled into a primitive first cell?
Simple mechanism I picture in my mind
I create it using solid modeling software, storing information in file
I transfer it to 3-D printer using data storage “stick”
3-D printer that uses inkjet technology but with a molten plastic rather than ink.
Prints one 0.3 mm thick layer at a time, making a 3-D solid part or system of parts.
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Who made the computer and 3-D Printer? Who encoded information in computer?
?
The Enigma of the Origin of Life
“The largest stumbling block in bridging the gap between nonliving and living still remains. All living cells are controlled by information stored in DNA, which is transcribed in RNA and them made into protein. This is a very complicated system, and each of these three molecules requires the other two--either to put it together or to help it work. DNA, for example, carries information but cannot put that information to use, or even copy itself without the help of RNA and protein.”
Kenneth R. Miller and Joseph Levine, Biology: The Living Science (Upper Saddle River, New Jersey: Prentice Hall), 1998, p.406-407.
What other say about the origin of life?
“ A profound difficulty exists, however, with the idea of RNA, or any other replicator, at the start of life. Existing replicators can serve as templates for the synthesis of additional copies of themselves, but this device cannot be used for the preparation of the very first such molecule, which must arise spontaneously from an unorganized mixture. The formation of an information-bearing homopolymer through undirected chemical synthesis appears very improbable.”
Robert Shapiro, Prof. Of Biochemistry NYU
What others say about the origin of life?
• “The chemistry of the first life is a nightmare to explain. No one has yet developed a plausible explanation to show how the earliest chemicals of life—thought to be RNA—might have constructed themselves from the inorganic chemicals likely to have been around on early earth. The spontaneous assembly of a small RNA molecule on the primitive earth ‘would have been a near miracle’ two experts in the subject (Joyce and Orgel) helpfully declared last year.” Nicholas Wade
New York Times
Critique of Comments
• They appropriately emphasize incredible difficulty in making RNA under pre-biotic conditions.
• This is very small part of a much larger problems of designing a very sophisticated system that is fully compatible.
Summary
• Life requires processing energy, storing information, and replicating.
• Each function requires molecular machinery—DNA, RNA, protein.
• Various machines must be compatibility.
• Machinery also needs to be programmed with information (DNA).
• This is a beautifully designed system.
• How is this possible?
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