Studies on the Origin of Life
Thermodynamics and the Origin of Life
Walter L. Bradley Texas A&M University College Station TX 77843
From Perspectives on Science and Christian Faith 40 (June 1988): 72-83.
The significance of thermodynamics to the origin of life has been widely debated for the past twenty-five years. In this paper, the thermodynamic significance of the origin of life are evaluated and the potential for such work to be accomplished with the available energy sources is determined. Relevant experimental work is interpreted in light of the thermodynamic analysis. Illustrations are included to assist persons not familiar with thermodynamics with its concepts.
Some creationists have claimed that the Second Law of Thermodynamics precludes a naturalistic origin of life Evolutionists retort that because the earth is an open system, there is no thermodynamic problem with the origin of a living system from simple compounds assumed to have been abundant in the early earth`s atmosphere The purpose of this paper is to evaluate the validity of these conflicting claims,
and to determine what one may say thermodynamically about the current origin-of-life scenario.
The minimum requirements for a simple living system must include the capacity to: 1) process energy (to make use of energy from the surroundings), 2) store information, and 3) replicate The simplest organic system proposed to date that is capable of these functions is the hypercycle of Eigen.l This system. consisting of a deoxyribonucleic acid molecule (DNA) and a minimum of forty proteins, is much simpler than the simplest known living systems; namely, the bacteria. Cairns-Smith has proposed an even simpler first living system based on silicates.2 However, his model is too general to allow a thermodynamic analysis at this time.
Furthermore, there has been essentially no experimental work to verify the basic hypothesis of Cairn-Smith's inorganic model Therefore, we will limit our analysis in this paper to the organic models of early life, in particular those requiring protein and/or DNA or RNA (ribonucleic acid).
Plants function like metabolic motors, capable of converting solar energy into chemical energy in the form of energy-rich compounds. These compounds are then utilized to supply the energy for the various processes required by the plant. Animals in turn eat the plants and utilize their energy - rich compounds to meet the animal's energy requirements Thus, living systems may be thought of as functioning energetically in a manner similar to that of an automobile. The automobile converts the chemical energy in gasoline into mechanical torque on the wheels. The engine and drive train make that conversion possible Within living systems, DNA, RNA and protein molecules, the components of chemical (metabolic) motors, are analogous to the pistons, valves, spark plugs. transmission, etc in an automobile.
As with an automobile energy flow through living systems can be easily understood and found to be quite compatible with the First and Second Laws of Thermodynamics. However. the origin of living systems presents a much more challenging problem. The British mathematician and philosopher Michael Polanyi has succinctly described the problem in the following way.3 He notes that the laws of chemistry and physics can be described using differential equations. However, it is in the prescription of the boundary conditions that specific form and function are obtained. To put it another way, there is nothing about automobile that defies the laws of chemistry and physics. Rather, each component can be shown to function in a way that is completely in harmony with the laws of chemistry and physics. yet you would never expect to have an automobile come into existence spontaneously Someone had to prescribe (through design and manufacturing) the conditions under which the chemistry and physics occur to achieve the purposeful end result of the conversion of chemical energy in gasoline into transportation. In a similar fashion, the mains problem to be resolved in our current origin-of-life scenario is how a most unlikely arrangement of complex organic molecules capable of processing energy. storing information, and replicating came into being.
The Second Law of Thermodynamics states that processes occurring in nature give a net increase in the total entropy in the universe tie, the total entropy in the universe is always increasing) Entropy is a statistical concept that measures the number of ways a system can be arranged Entropy is also related to information A system requires a large number of bytes of specific information would he one with a very low entropy Thus, the very complex and specific arrangement of molecules associated with even a simple living system constitutes a very low entropy arrangement of the system if normal processer in nature increase the entropy (decrease the information) in the universe, how then does one rationalize the origin of life. which requires a local decrease in entropy (or increase in information)?
The two most common answers given to this question are equally incorrect, in my opinion Some creationists say that the Second Law of Thermodynamics renders impossible the chemical origin of life because of the infusion of information (decrease in entropy) required.4 Some evolutionists respond that the required decrease in entropy is precluded by the Second Law of Thermodynamics only in a closed system They would argue that energy flow from the run mates the earth an open system, and that this energy flow is somehow capable of producing the required decrease in entropy (increase in information).5
Strictly speaking, the earth is an open system, and thus the Second Law of Thermodynamics cannot be used to preclude a naturalistic origin of life. However, energy flow through the system has only been shown to produce negative thermal entropy (affecting the distribution of energy in the system), whereas the origin of life requires a significant decrease in the configurational entropy (affecting the distribution of mass in the system). 6 G. Nicolis and Nobel laureate I. Prigogine have alluded to this problem:
Needless to say, these simple remarks cannot suffice to solve the problem of biological order. One would like not only to establish that the Second Law (dS1 > 0) is compatible with a decrease in overall (system) entropy (dS <c 0), but also to indicate the mechanism responsible for the emergcnce and maintenance of coherent states.6
If one wishes to restore a messy room to its original neat (low-entropy) condition, one must do work on the system Although throwing a stick of dynamite into the room will provide a significant flow of energy through the system. it is doubtful that the configurational entropy of the room will be lowered or that the room will be restored to its original low-entropy state The energy flow through the room needs to be directed if the configurational entropy of the room is to be reduced: i.e, someone needs to do very specific kinds of work to restore it to a neat rendition. For precisely the same reason, it is insufficient simply to assume that solar energy is capable of generating the necessary information (or configurational entropy) to account fur the first living organism.
In this paper I will quantify the various kinds of work required to produce a protein molecule, and then evaluate what. if any, kinds of available energy might be capable of accomplishing these various components of work The results of prebiotic simulation experiments will be reviewed in light of these calculations. It should he emphasized that the production of a simple protein is a relatively small step in the formation of a simple living system. Yet even this small step has proven to be very difficult to explain theoretically or demonstrate in the laboratory under prebiotic conditions.
Synthesizing a Protein from Biomonomers
Protein molecules consist of long molecular chains of smaller building blocks. To construct a functional protein from these simpler building blocks, one must assemble the building blocks in a very particular way. First, work must be done to get the amino acids to loin together to form a polymer chain. Second, one must include only lefthanded amino acids in the chain, even though a "prphiotic sonp" would be expected to have equal concentrations of L and D amino acids. Third, one must also connect all of the amino acids with so - called peptide bonds. Fourth, the sequence of the various types of amino acids is important since it determines the three - dimensional topography which in turn determines function, as shown. Finally. it is crucial that only amino acids be incorporated in the polymer chain, even though many other organic molecules capable of reacting with amino acids would be present in any "prebiotic soup." Let us examine the amount of work required to meet these rather stringent requirements to form a functional protein.
The work required to create a protein, or functional polypeptide. from the twenty different amino acids found in biological proteins can he described using the change in Gibbs Free Energy ( deltaG)
deltaG = deltaH - TdeltaS = deltaE + PdeltaV - TdeltaS (1)
where deltaH is the change in heal energy or enthalpy, deltaE is the change in bonding energy, PdeltaV is the pressure times the change in volume (this term is negligibly small), and TdeltaS is the temperature in degrees absolute times the change in entropy. The change in Gibbs Free Energy during a chemical reaction, also called the chemical affinity, is a measure of the energy that would be liberated or absorbed during a reversible chemical reaction A positive value for deltaG indicates movement away from chemical equilibrium. which would require work to be done on the system. A negative value for deltaG implies a movement toward equilibrium, which should occur spontaneously (unless some activation barrier must be overcome).
The change in entropy can he divided into the change in thermal entropy and the change in configurational entropy; terms having to do with the distribution of energy and matter in the system respectively:
deltaS = deltaSth + deltaSconfig (2)
Finally, the configurational entropy can be further subdivided into four components having to do with the above-mentioned specific arrangements of the amino acids into polypeptidcs to obtain biological function:
deltaSconfig = delta S1c + delta S2c + deltaS3c + deltaS4c (3)
The configurational entropy work associated with obtaining only L-amino acids in the polymer chain will be called - TdeltaS1c. The configurational entropy work to obtain only peptide bonds will be called - TdeltaS2c, The - TdeltaS3c, term refers to the additional configurational entropy work to get the proper sequencing of the twenty amino acids in the polymer chain. Finally. - TdeltaS4c, refers to the sorting and selecting configurational entropy work, or the work to select only the required set of amino acids to be included in the polymer chain from a "prebiotic soup" which contains many different organic molecules. Since each of these terms requires an ordering (or infusion of information) in the system, the respective entropy changes, deltaSic, are all negative Noting in Equation 1 that the entropy term is -TdeltaS, we can see that a decrease in entropy (deltaS < 0) results in a positive contribution to deltaG. Increases in deltaG represent work to be done on the system, either by available energy within the system (e.g., deltaH < 0 could compensate for - TdeltaS > O) or by external work done on the system.
Using the statistical definition of entropy:
S = k lnphi (4)
where k is Boltzmann's constant and R is the number of ways the system can be arranged, one may calculate the value of the various components of the configurational entropy work. We shall assume the formation of a polypeptide of 101 amino acids in a "prebiotic soup" will normally contain 50%L- and 50% D- amino acids, with 50% peptide bonds, and an essentially random sequence of amino acids.7 Biological function will be assumed to require all L-amino acids. all peptide bonds, and only specified amino acids at each of the 101 positions Biological function might he possible with a somewhat less stringent assembly requirement than I have assumed. For example, the type of amino acid at the 101 positions in the amino acid chain may critical at only 40 - 50% of the positions. Thus, we will overestimate somewhat the work requirements for configurational entropy term deltaS3c. However. requirement for deltaS4c, would prohably he much greater than all three of the other terms combined, but cannot be calculated without a detailed knowledge of composition of the "prebiotic soop" The magnitude of the three configurational entropy terms that can calculated with the stated assumptions should exceed the actual configurational entropy for all four terms.
The configurational entropy work at T equals 300K to obtain only L-amino acids is given by:
-TdeltaSic = - Tk(ln l - ln2101) = 4.2
cal/gm (5)
where k is Boltzmann's constant and has a value of 1.38 x 10-23 J/K-atom). The molar weight of a polypeptid of 101 amino acids has been assumed to be 10,000 grns, since the molar weight of amino acids on average would be about 100 gms. The configurational entropy work to obtain all peptide bands in a system where typically only 50% peptide bonds are obtained (in prebiotic simulation experiments') is calculated as follows:
TdeltaS2c = - Tk(ln l - ln 2101) = 4.2 cal/gm (6)
The configerational entropy work required to give sequencing that results in catalytic activity may be calculated as follows:
-TdeltaS3c = - Tk(ln l - ln 2101) = 18.2 cal/gm (7)
As has been noted, the sorting and selecting configurational entropy wort, or work required to select the right set of amino acids from a much larger set of organic chemicals one would expect to find in a "pre biotic soup" cannot be calculated since we do not have a detailed knowledge of the chemical composition of the "prebiotic soup."' The change in the deltaE + PdeltaV - TdeltaS term (see Equation 1) may be estimated from the widely quoted work of Borsook and Huffman that polymerization of two amino acids into a dipeptide increases the Gibbs Free Energy (not counting the configurational entropy work) by 3000 cal/moles For a polypeptide of 101 amino acids (100 peptide bonds), the increase in energy (or the required work) is 300,000 cal/mole, or 30 cal/gm, assuming a polypeptide molecular weight of approximately 10,000 gm/mole, as previously noted.
The total work required to form a polypeptide from amino acids can now be calculated to be:
deltaG = deltaE + PdeltaV - TdeltaSth -
TdeltaS1c - TdeltaS2c - TdeltaS3c - TdeltaS4c
= 30.0 + 4.4 + 4.2 + 18.2 + ?
= 56.6 + ? cal/gr (8)
Again, let me reiterate that the complex arrangement of molecules necessary to give a functional protein represents a decrease in entropy (deltaS < O) Thus, the various entropy terms in Equation 8 (-TdeltaS) all contribute to the work required to make a functional protein, as described by the magnitude of deltaG
To illustrate the importance to biological function of getting all the configurational entropy work done proerly, consider the problem of trying to write the sentence "HOW DID LIFE BEGIN? First we illustrate the problem of having a mixture of L- and D- amino acids rather than all L-amino acids Our original statement becomes harder to understand: the function of communicating information is partially lost
H OM DID FL EE RE CI ~ i FIX!!!!!!!!!!!!!!!!!!
The problem that occurs when nonpeptide bonds are found in our polymer is illustrated by using oar original statement but joining the letters together in unconventional ways to represent nonpeptide bonds Again a loss of function is evident; the original message is obscured.
HO~ CIIO -II~w maolze FIX!!!!!!!!!!!!!!!!!!!!!
Finally, the problem of improper sequence is illustrated by taking our original statement and rearranging some of the letters, totally obscuring the original message
DIF HEG INBW ODIEL?
If all three of these problemr were superimposed, the original message would be impossible to decipher. illustrating total ins of function. The same degradation of biological function results when the polymer does not have all L- amino acids, all peptide bonds, or proper sequencing of amino acids.
The greatest problem, however, is how to draw from an "alphahet soup of many English letters (reinterpreting amino acids) and Chinese, Creek, and Hebrew symbols (representing other organic moleculer) only the following set of letters: one each of H, O, W, L, F. B, G, N: two Ds and Es; and three Is The crucial question is whether energy flow through the system is capable of doing the various components of work indicated in Equation 8 We will address that question in the next section. relying heavily on experimental results from the literature.
Can Energy Flow Do the Required Work?
Experimental work to date has utilized mainly two approaches: 1) a two-step approach of first making amino acids from gaseous constituents, and then polymerizing them into polypeptides: and 2) a single-step approach of going directly from gases to polypeptides The first approach war developed by Fox9; the second was pioneered by Matthews.10
Both approaches are able to successfully do the deltaE + PdeltaV - TdeltaSth work, or chemical energy and thermal entropy work. Matthews' approach is successful in doing these components of work because he begins with energy rich compounds such as cyanide The polymers he forms have a larger bonding energy (more stable chemical bonds) than the gaseous precusors from which they form, so his chemical reaction goes "downhill" energetically. In Fox's approach, one begins with energy-rich gases such as ammonia, methane, and hydrogen and reacts them to form amino acids and other organic compounds. That reaction is also energetically "downhill." However, the chemist then separates the small percentage of amino acids from the many organic compounds formed from the gaseous reactions and polymerizes them, this step being energetically "uphill." For accomplishes this step by thermal polymerization, heating his amino acid mixtures at a temperature that drives off the water formed as a byproduct of the condensation reaction.
Removal of the water effectively prevents reversal of the reaction. Unfortunately, energy flow through the system has been found to be quite ineffective in doing the configuational entropy work .&&&&&&& Doer either For's or Matthews~ approach produce all L amino acids? The answer w no, unless the chemist in For's approach selects out of the initial potpourri of
V
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organic chemicals only L-aminu acids fur use in second step In that case, one might ray that theeh doer the T~S,, configurational entropy s Equation 8) Does either approach prodllcr ail p bonds? The answer is again no Tcmuni et al found, using nuclear magnetic resonance IUMR). Fori thernlal "proleinoids~` have only 50~ poi bonds' The situation with Matthcws' pl,lymrrs is worse bpca~lu his reaction pn,ducl dl,c* 001 1 solely of amino acids, mlrch less of all pr…ptirlp between the amino aciiB That ii not surprising; thews' approach does not allow the lururv of havii chemist remove only the anrinu acilli C,r use in second step of the erperiment 70 pill ii anotherl For's approach ilas the chemist also dllinR the -1 wurL: Matihews` approach leaves it to chance, chance is not very ef fective in doing this sort of ul
For such an incredibly improba eoent as the current scenario of t origin of life, chance is not an adequate cause.
Does either approaclr prodla:t: an amino sequence that gives significant catalytic ar:tivity) and Fur have reported a;LI% increase in a che reaction catalyzed by their protcinoidr. compare the same reaction wllell tile rate is nlmsur~d in absence of pruteinoids' Calulvies in iivillg systems a 10' increase in tire reaction rate While one erpect primitive proteins to be ir.ss efficient modern ones. Dose and For'r protcinoirls give cat activity ill orders of magnitude i,,, than that foun biological eorympr (proteins) today. anci much ton to overcome the "thcrmai noire" level in an) rp tie, the degenerative furt…rr resulting frnni agitation)
as :e Thus, energy flow tllrough a model Lirehinlic ii lal has been shown to he capable of doing the hE i ta TL\S,h components of rerluirr~l worli for pollm a tion of protein, but not tire conligllrational components of worlt Forlhrrmorc, there is no cal basis for postulating that energy flow ti iof system is capable of supplying tht rerlllirr:d eonfigr ow tional entropy work. or information The worl ec Prigogine has indicated that a highly conitrainedl oer tem can produce an order analogolrs to that foua L- crystals, hul that is a far cry fnirn the informal tin intentive macromolecules cllaractcristic of living iuf tcms6 Furthermore, the order produced in Prixoe
lahe
PERSPECTIYES ON SCIENCE ~ND CHRISTIIII
THERMODYNAMICS ANT:
systems is of the same magnitude as the information implicit in the boundary constraints
Our answer to the question "Can the various work terms summari~ed in Equation 8 be accomplished by energy flow through the system?`~ is clearly "NO.~' based on experimental work to date. To be more specific. energy flow through the system is capable of doing the bonding energy and thermal entropy compo nents of the total wort term, but thus far has been completely inept at doing the configurational entropy (information) work required Although the magnitudes of these two types of wort are similar (see Equation Ii), the coupling of the energy flow to the required configurational entropy (or information wort) is extremely difficult, if not impossible. Apart from such coupling, the formation of biologically functional macromulecules is not possible
One final area of misunderstanding needs to be addressed with regard to thermodynamic problems and possibilities associated with the origin of life The freering of water is often used to argue that ordering may occur both easily and spontaneously" To evaluate this contention, one may writs an equation similar to Equation 8 for freeling water with appropriate energy terms, as follows, at one atmosphere of pressure:
ac-aH-T(~Sa+~S~) oc- -8ncal/gm 1` ( 293 [cal/gm]/K) (9)
Water freezes spontaneonsly when ~G is less than ~ero From Equation Y, freeling can be seen to occur when the temperature T is less than 2731(. Thus, the freezing of water requires only that the thermal agitation be reduced sufficiently to allow bonding forces to draw the water molecules into a crystalstructure A comparison of Equation 9 to Equation II indicates a fundamental difference between the freezing of water and condenrationpolymerilation chemical reactions: namely, the change in bonding energy is negative in one case and positive in the other. One cannot make the change in Gibbs Free Energy (L\G) in Equation 8 negative, and thus make the reaction spontaneour, by adjusting the temperature
An analogy may be useful to illustrate the lignificance of this sign difference if you have a pool table with a recessed area in the center of the table, you would not be surprised to find all of the pool balls in this recessed area rather than randomly arranged around the table, unless you agitated the table quite strongly (analogous to heating ice above 273K) On the other hand, if the center of the pool table had a large hump with a small dip in the center of the hump (analogous to
THE ORIGIN OF LIFE
pnlymerizing amino acids), you would find it quite difficult with any degree of agitation to accumulate all of the pool balls an top of the hump in the small dip It would require strong agitation to get the balls up the hump and such strong agitation would simultaneously jar free from the small dip whatever balls you might already have accumulated there. Thus, while the freer ing of water is seen to be quite easy to accomplish by simply adjusting the temperature, no such possibility erirts for the cundpnsation-polymeri~ation reactions needed to make DNA and protein. Thus, freering of water and other phase transformations are seen to be irrelevant to the type of ordering and information production required for the origin of life
Is Chance a Reasonable AlternativeT
It has previously been noted that there does not seem to be an obvious way that the available energy flow in the "prebiotic soup~~ can be harnessed to do the required configuration entropy (or information) work to make even a rimple protein, much less a collection of ruch macromolecules to provide minimal life fllnctions
If the information in a living system is illustrated by a book, the accidental formation of a new protein is equivalent to incrementing the letters on one page and producing an alternative but meaningful paragraph.
There is a tendency on the part of some scientists, when confronted rith~this dilemma, to respond: "it still could have happened by chance" For erample. one might argue that the magnitude of the work required to rednce the volume occupied by one mole of an ideal gas by 50%, if done isathermally and in a reversible manner usmg a piston, can be calculated as follows:
T~S - Tk Lln IN - In 2"] - TtN ln2 - RT ln2 - 416 cal/mole 110)
where N is Avoeadro's number and T is assumed to be 3WK. This much work will place all of the molecules into a volume only half the original volume without any reliance an chance On the other hand, it is conceivable
WALTER L. B
that all of the molecules could accidentally find themselves in half of the original volume, apart from any ,ort being done onthe syrtenl However, the prohability of soch a chance occurrence ir only L1/2]eru~ or LO'"" Thus, while one coold argue that the volnme of gas could be reduced50% by chance, it iS "Ot very likely Horevcr, it becomes very believable that a~ch ,, event could occur if the prescribed amount of work is performed on the system using a piston.
Chance is not a very likely substitute fo' Some mechanism to p2'f"m the required work to mate a functional enzyme (prot"in), (or the reason lust stated For example, thep,,b,bility of obtaining all L-amino acids, all peptide bonds, anderactly the right seqaencr of 100 amino acids would be given by:
,_I1/21'"x [1/21'"x Il/zol'm-3 x 10181
If one took all of the orp~anle matter in the universe and used it to make amlno acids which were then allowed to it would still be continuously react for five billion years, ~~~ such incredibly unlikelythat one would malre even protein Yet one simple protein is hardly a prototype for ....rly living syrtem…
It is appropriate to note that snch appeals to chance rhould not be confuredwith a scientific explanation A scientific elpla""tion would postulate a model which, given the age of the.nivsrse and the amount of organic ,,,, in the universe, would predict with reasonable probability a rucccsdul tormation.b only of a solitary protein b~lt a family of sach macromoleculrr Whirh could provide the minimal functions of an early living system For such an incredibly improbable event as the c,rrent scenario of the origin of life, chance is not an adequate cause Rather it is the "God of the gapr of the atheirt ~mtil a morereasonable (believable) naturalistic first cansecan he found
Doolittle" and Thwaites 12 have attached great rigni( icance to the "accidental~` formation of a new functional protein alleged to have occurred in the pOADZ plasmid of Flavohocterium Sp. K17213 in my opinion they greatly ovprertimate the significance of SLl"h a finding, if indeed it is true if the information in " illustrated by .boot, the accidental ~j~t:~~ed;al%BW protem is equivalent tO incrrment-
ing the letters on one page ~,d producing an alternative but meaningful pa'aR'hph… It is hardly equivalent to the formation of the boot itself with the letters all properly arranged on the page (all L-amino acids with peptide bonds) Even F~,.t al. have minimized the role of chance as anadequate explanation to' the origin of biological information sufficient to produce the necessary minimal life functions mentioned al the beginning of thispaper Fox et al. ray:
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BRADLEY
The parfiEular cnnjuncli.ln of rt.,ml that are nrcelsrry fur life urms in Lr oxrrrdingly imnmhable. rimiirr in tile ch~nrr that a monliey al a lyDrrrilcr rill pnlduca TLIF OHIGIN OF SPECIFS "
in summariung this section, it is clear that appeals to chance are no nBititotP for a hona fide scientific
enplanation
Review of Relevant information from ISSOL's 8th International Meeting Several papers at the 19R6 RerLeley, California meeting addressed issues related to those presented in this paper First, the geuchpmis$ and artrophysicisb seem to have come to a clear consensus that the earth'l early atmosphere never contained any significant ammonia or hydrogen and, at best. only very small
The impression provided by the debate was clearly that at present we simply do not know how Iz~fe originated, Each side clearly showed the inadeyuacies of the other's model and neither side made any signz~fican attempt to defend their own model,
amounts of methane Since all of the prebiotic sl of biomonomers tie., simple molecular huilding such as amino acids, bases, etc) in Miller/Urel-t: experiments have used genermll concentrations ammonia, hydrogen, and/or rnethane, such results of questionable significance The biochemists ar@ that they must hare an apprcciahlr amolmt of at I one of these energy-rich gases. and the astrophyr insisted that such was not present in the early ei atmosphere if one begins with energy-rich gases as ammonia, hydrogen, or methane, the formatil amino acids and other hiomonomen is energetil downhill On the other hand, if one begins with atmosphere now thought to erisl on the early e jnamely, carbon dioride, nitrogen, and water), formation of amino acids is energetically uphill. I energy or electrical discharge has proven to he eff in facilitating the chemical kinetics to move an tically favorable reaction (one that goes dor forward, hut such energy sources have not proven very helpful in driving an energetically unfave reaction uphill it should he noted that the of such building blocks has been assllmed in
THERMODYNAMICS A
F(gul
~Vh~h~ad~l~fie attention given to tire proper assembly of
In recent years. some scientists have postulated that maybe the first living system was based on RNA Certainly RNA is a much ht~tter candidate for such a role than protein However, a presentation by Robert Shapiro entitled "Prebiotic Ribose Synthesis: A Critical Analyris," demonrtrated convincingly that we have no basis for believing in a prebiotic origin for RNA He concluded his presentation with the following summa 'y "Our present understanding of prebiotic rihose synthesis offers no support fur the prrsumption that significant amounts of oligonucleotider, or even nucleu'ids. were present on the early earth... l,here warp no technical challenges to his presentation, only a couple of complaints about his being so pessimistic
An interesting debate was held between the proponents of original life based on RNA and the advocates of original life based on protein Slrpporters of the proteinbased theory argued convincingly that RNA was much too complicatrd to have arisen prebiorically. much as Shapiro had argued in his paper earlier in the conference. Proponents of a RNA-based origin of life argued in an equally convincing fashion that protein by itself was too i"ept to provide the necessary biological functions foreven a simple living system The impres sion provided by the debate was clearly that at precent we simply do not Lnow how life originated ~ach side clearly showed the inadequacies of the other.s model. positions Biological function might he possible somewhat less stringent assembly rpqllircment have assumed. For example. the type of amino aeil the 101 positions in the arnino acid chain may critical at only 4050% of the positions Thus. we overestimate somewhat the work requirements for configurational entropy term ~S, However. requirement for eF,, would prohahly he much gr than all three of the other terms combined, hut ea be calculated without a detailed knowledge of composition of the "prehintic joop" The magnitud~ the tllree configurational entropy terms that can calculated with the stated a~unrplions should exceed the actual configurational entropy for all terms
The configurational entropy work at T equals to obtain only Lamino acids is given by:
-T~S,, - Tk(Lnl ln210') 300 k x 10X x 10" I/g-atom x (O 291/atom x 6 x IO"atom/mole x .24 calj~ x 10,WO moler/gm - 4.2 cal/gm (5)
Note k in the above equation is Roltlmanni e~ and has a value of 158 rl02ll/(atomK) The weight of a polypeptids of 101 amino acids has br assumed to be 10,000 grns. since the molar reip~ht
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WALTE:R L. BI
F(gure :
postulate" At present. Cairn-Smith.s model suffers from lack of any elperimental support or any theoretical model that can erplain the fundamental problem :~~i~ B naturalistic origin of life; namely,
A sRond possibility is that new physical laws might be discovered which couldaccount for the information production necessaryin generating the first simple living system. While possible. such a hypothesis at present is little more than a metaphysical statement of faith that all effects must be found to have natural
causes.
Third, Hoyle and Wicltramacinghe and Sir Francir CricL have suggested life came here from another pB~~a." The interesting suggestion, justifiably based
O" Senous misgivings about current scenarios of a naturalistic origin of life on earth, actually does no more than transfer the problem of information to some remote location in the universe, as these authors note in their respective books
A fourth alternative is to posit an intelligent creator as the source of the information intensive first living organisms. When one compares the rock formations in Zion National Monument in Utah to those on Mt Rushmore in South Datota (see Figures 6 and 7), the indication of intelligent activity by a sculptor as contrasted to random forces in nature is clearly illustrated.
ii
~. BRAI)I.FY
ure7
In a similar fashion, the incredible complerity ciated with even the simplest living systems c suggests an intelligent creator. An unbiased r could hardly deny the rearonablenerj of such ence from the scientific evidence
Some will react to the suggestion of an intelll creator by suggesting it is a traditional "Gal of gaps" argument. However. I would strongly argue such a reaction misses what has been the main p this paper A "Gal of the gaps" argument posits cc erplain something not yet erplainable by physical chemical processes, apart from any evidence forsu hypolheris. In this paper, I have tried to argue that is posited not because of what we do not under~ but because of what we do understand. The m piece to the origin of life puzde is a dramatic function) increase in information. Human erpel consistently indicates such increases in informati always the result of intelligent activity, by man case of machiner, presumably by God in the case first living systems
I recognile that God could have created through miracle, entirely through process, or some combination of the two I believe that scientific understanding clearly suggests God I. comb~nation of miracle plus process to create the living system. Such a hypothesis is consistent wit~ Genesis I account of origins
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THERMOD~AMICS ANI
REFERENCES
1M. Eigen, Self Organization of MatterOrylumllon of Mnnc. sad rh. Ilolunm of BWIOJIE…I M…EmmolTulrs.……WPNolU'YW Vol 58(1811), P "65 'he ClirnrSmith CmPlu Taicoulr and ih~ Mirrnl h…p~n of Llfr iNnr lo~; ClmbrMg~ Oniu.nity P...., IBBZ) hi p,lnn~i. ..LiipTiul~andm$Ch.mu~r) IndPhyaio.'~Chsm EngrN~ur, hu$urt 11, 1961, P 51 'H ~or"r, INn(~fir D~t(onUm (Ssn Dirgo, C*; CLP puMuh.n. 1DiP 1H I Mnm*it., Ensrgy Fior In P~logy (N.- lort: *EldrmiE prar, 18~81. …c ~P~~3~nd, p~,,pr, SrilOrgaiunM1 (n Nnrin~iitblum SYrlSM iN.r nodi; lohn Wih… Isll). ~ ~ 'P~ rrmuul, L Ps~lillo, L Imrs, L B~nde~li, snd S *ndmi,'~Struen~usl Ch.rsetniuti.nof~rm…iPrrbmtiE ~aiypplld"..l Mdm.lnr Erd, Vol 7 (LB16), P LM 1H Baruoli md HM Hd(rmn. ChPmUlry of dm(nu *ndr and ~mL(n, ni CL~SEhmdliSprindi.ld, M~: Chsri.. C Thom…ICal.l8141.P *eZ SW Fnlsndli Dox.Mdauh. EuolulYn and chr Ongin of L~ir LNrr 10CN MltLh.x~r …d R L Morr, ….prEblOloyESI Piol.in Sl"thsu,'~ Pm Nnt *rnd Sn oS.vol sa(le66), P leai
The mantle of Christ be p To shade theefrom thy n The mantle of the Cod of ii) To be thy champion an
From Nw Moan of thr E~uona; Pmyln from Ihr ~ghlnnd. and I~ 1881
ii
UD THE ORIGIN OF LIFE
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"II ~II~. prram6on lit Eonia,cn,,,"Th.Ym re *thrilm." Ddlu Tcru, 1885 1W M Th-nlln, …'bn hth.illl Y1Lx oi ih. Ongin oi LIV' prrxn.tion …I eonfuane~an"~Mrmrr *thnrm,~' Dsilsr, Tlulr. 1~85 YS Ohno. "8lrth of … un~u..nvun. trom …n Ilt.mnlirr ruding fr…mrai ib prr.lltEd. intnnsill rrput…tion. oding r~qutn~,~' Pnr Noll *rod 5*( VS,Vai 81(188I). p12rlP1-2(15 "MW Ho, P S…undm …nd 5 Fo…. "* NLI P1Tsd~ll IOI EVOIYllOn……~ NPUI SeMI(Y(, 21 P~ 1885. pll 'Iw Ponoraon, "Thrrmodpn…mm nnd EJiution,~' Th.*mrrVon dlMa( lurr. Lggllp 39-W irramtd imm S~cuca Cnnfrat Crulllan(rlr. ad LIvnaII CdfrO (Nrx~ Yori: WW Nonan, IBW) I* Crsm.r. ~…6mml Evoluuan nnd the S~md Lnx~ of Th.rmodynsmia.~~ Ongma ond ChnneP, d DL Willu (Elgin. IL: hmarrnn LirnBiir *ffiii.lion, Ima) 9r h~ncL Hqlr Thr Int~gwr Un~mrr (N.r lori Hell. Rinchsn.nd
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