Naturalistic theories have many insurmountable problems, dilemmas, if not for their anti-theistic commitment, many brilliant, renowned persons would never bother to conceive such a stupid wishful thinking, because the odds for a mere protein to form itself without intelligent influence are astronomical, in fact, impossible! Read now some scientific facts against the homochirality to happen by chance.
An organism is composed of countless molecules, the “building blocks” of life. Nearly all biological polymers must be homochiral (all its component monomers having the same handedness. Another term used is optically pure or 100 % optically active) to function. All amino acids in proteins are ‘left-handed’, while all sugars in DNA and RNA, and in the metabolic pathways, are ‘right-handed’. Whether or not a molecule or crystal is chiral is determined by its symmetry. A molecule is achiral (non-chiral) if and only if it has an axis of improper rotation, that is, an n-fold rotation (rotation by 360°/n) followed by a reflection in the plane perpendicular to this axis maps the molecule on to itself. Thus a molecule is chiral if and only if it lacks such an axis.
A 50/50 mixture of left- and right-handed forms is called a racemate or racemic mixture. Racemic polypeptides could not form the specific shapes required for enzymes, because they would have the side chains sticking out randomly. Also, a wrong-handed amino acid disrupts the stabilizing α-helix in proteins. DNA could not be stabilised in a helix if even a single wrong-handed monomer were present, so it could not form long chains. This means it could not store much information, so it could not support life.
To begin with, it’s a well known FACT that homochiral molecules are never found outside a cell (except, of course, in labs, under the human, therefore intelligent, manipulation). Why? Laws of physics, dear!
consequence of the Laws of Thermodynamics. The left and right handed forms have identical free energy (G), so the free energy difference (ΔG) is zero. The equilibrium constant for any reaction (K) is the equilibrium ratio of the concentration of products to reactants. The relationship between these quantities at any Kelvin temperature (T) is given by the standard equation:
K = exp (–ΔG/RT)
where R is the universal gas constant (= Avogadro’s number x Boltzmann’s constant k) = 8.314 J/K.mol.
For the reaction of changing left-handed to right-handed amino acids (L → R), or the reverse (R → L), ΔG = 0, so K = 1. That is, the reaction reaches equilibrium when the concentrations of R and L are equal; that is, a racemate is produced. A famous textbook correctly stated:
‘Synthesis of chiral compounds from achiral reagents always yields the racemic modification.’ and ‘Optically inactive reagents yield optically inactive products.’ (Morrison, R.T. and Boyd, R.N., 1987. Organic Chemistry, 5th ed. Allyn & Bacon Inc. p.150)
It also states:
‘We eat optically active bread & meat, live in houses, wear clothes, and read books made of optically active cellulose. The proteins that make up our muscles, the glycogen in our liver and blood, the enzymes and hormones … are all optically active. Naturally occurring substances are optically active because the enzymes which bring about their formation … are optically active. As to the origin of the optically active enzymes, we can only speculate’
Nonetheless, they (the naturalists) are “sure” of the casual origin of everything… They just can’t explain HOW could it happen, nor can they show the farthest, slightest evidence of the nothingness creating things that violate its laws, such as homochirality! English biologist John Maddox called it “an intellectual thunderbolt that natural proteins should contain only the left-handed forms of the amino acids.”. But it was not for the lack of efforts and guesswork. The famous Oparin once went on to say:
“The probability of the formation of one antipode or the other is therefore the same. As the law of averages applies to chemical reactions the appearance of an excess of one antipode is very improbable, and, in fact, we never encounter it under the conditions of non-living nature and in laboratory syntheses . . . .
In living organisms, on the contrary, the amino acids of which naturally occurring proteins are made always have the left-handed configuration. . . . This ability of protoplasm selectively to synthesize and accumulate one antipode alone is called the asymmetry of living material. It is a characteristic feature of all organisms without exception but is absent from inanimate nature.
Pasteur pointed out this fact as follows: “This great character is, perhaps, the only sharp dividing line which we can draw at present between the chemistry of dead and living nature.”” (A. I. Oparin, Life, Its Nature, Origin and Development (New York: Academic Press, 1961), pp. 59, 60)
Ever since, many theories were proposed, in an effort to solve this unbelievable puzzle, but they have all failed, as we’re going to see some now.
How can we separate the left from the right?
It’s not that simple! First of all, you need of intelligence behind the process… To resolve a racemate, another homochiral substance must be introduced. The procedure is explained in any organic chemistry textbook. The idea is that right-handed and left-handed substances have identical properties, except when interacting with other chiral phenomena. The analogy is that our left and right hands grip an achiral (non-chiral) object like a baseball bat equally, but they fit differently into a chiral object like a left-handed glove. Thus to resolve a racemate, an organic chemist will usually use a ready-made homochiral substance from a living organism.
However, this does not solve the mystery of where the optical activity in living organisms came from in the first place. An world conference on ‘The Origin of Homochirality and Life’ made it clear that the origin of this handedness is a complete mystery to evolutionists (Cohen, J., 1995. Science, 267:1265–1266). The probability of forming one homochiral polymer of N monomers by chance = 2–N. For a small protein of 100 amino acids, this probability = 2–100 = 10–30. Note, this is the probability of any homochiral polypeptide. The probability of forming a functional homochiral polymer is much lower, since a precise amino acid sequence is required in many places.
A further problem is that homochiral biological substances racemize in time. This is the basis of the amino acid racemization dating method. Its main proponent is Jeffrey Bada of the Scripps Institution of Oceanography in La Jolla, California(Bada, J.L., Luyendyk, B.P. and Maynard, J.B., 1970. Science, 170:730–732). As a dating method, it is not very reliable, since the racemization rate is strongly dependent on temperature and pH, and depends on the particular amino acid (Gish, D.T., 1975. Impact series #23, ICR). Racemization is also a big problem during peptide synthesis and hydrolysis. It shows that the tendency of undirected chemistry is towards death, not life.
Beta decay and the weak force
β-decay is one form of radioactive decay, and it is governed by one of the four fundamental forces of nature, the weak force. This force has a slight handedness, called parity violation, so some theorists thought β-decay could account for the chirality in living organisms. However, the weak force is aptly named—the effect is minuscule—a long way from producing the required 100 % homochirality. One specialist in the chirality problem, organic chemist William Bonner, professor emeritus at Stanford University, said, ‘none of this work has yielded convincing conclusions’. Another researcher concluded:
‘the exceptional prebiotic conditions required do not favour asymmetric β-radiolysis as the selector of the exclusive signature of optical activity in living nature.’
Another aspect of parity violation is that the L-amino acids and D-sugars have a theoretically slightly lower energy than their enantiomers so are slightly more stable. But the energy difference is immeasurable—only about 10–17 kT, meaning that there would be only one excess L-enantiomer for every 6×1017 molecules of a racemic mixture of amino acids.
Some have proposed that a homochiral polymer arose by chance and acted as a template. However, this ran into severe problems. A template of 100 % right-handed poly-C (RNA containing only cytosine monomers) was made (by intelligent chemists!). This could direct the oligomerisation (formation of small chains) of (activated) G (guanine) nucleotides. Indeed, pure right-handed G was oligomerised much more efficiently than pure left-handed G. But racemic G did not oligomerise, because:
‘monomers of opposite handedness to the template are incorporated as chain terminators … This inhibition raises an important problem for many theories of the origin of life.’ (Joyce, G.F., Visser, G.M., van Boeckel, C.A.A., van Boom, J.H., Orgel, L.E. and van Westrenen, J., 1984. Nature, 310:602–4)
Do you like probabilities? Let’s see what Dr. Harold J. Morowitz of Yale University has found on his extensive research for discovering the theoretical limits for the simplest free-living thing which could duplicate itself.
“He took into consideration the minimum operating equipment needed and the space it would require. Also, attention was given to electrical properties and to the hazards of thermal motion. From these important studies, the conclusion is that the smallest such theoretical entity would require 239 or more individual protein molecules.
This is not very much simpler than the smallest actually known autonomous living organism, which is the minuscule, bacteria-like Mycoplasma hominis H39. It has around 600 different kinds of proteins. From present scientific knowledge, there is no reason to believe that anything smaller ever existed. We will, however, use the lesser total of 239 protein molecules from Morowitz’ theoretical minimal cell, which comprise 124 different kinds.
It was noted earlier that there obviously can be no natural selection if there is no way to duplicate all of the necessary parts. In order to account for the left-handed phenomenon, chance alone, unaided by natural selection, would have to arrange at least one complete set of 239 proteins with all-left-handed amino acids of the universal 20 kinds. There is reason to believe that all 20 of these were in use from the time of life’s origin.
Using figures that were furnished by Morowitz, it can be calculated that the average protein molecule in the theoretical minimal living thing would contain around 445 amino acid units of the usual 20 kinds. One of the 20 types of amino acids, glycine, cannot be left- or right-handed, because its “side chain” is not really a chain, but merely a hydrogen atom like the one opposite it. It can be presumed that this minimal theoretical cell would in many ways resemble bacteria in its make-up. In some bacteria, glycine accounts for just over 8 percent of the total amino acid molecules, so we will estimate that in the average protein of the minimal cell, there will be 35 glycine units in the chain. That will leave 410 of the total 445 which could be either left- or right-handed.
If amino acids had been formed naturally in the “primitive” atmosphere, they would have occurred in statistically equal amounts of the left- and right-handed isomers. This became clear from experiments described in the preceding chapter. That means, then, that if a protein chain is to form by random linkups, all 410 of the nonglycine sites could be occupied with equal ease by either L- or D-type amino acids.
The first one has a 1 out of 2 chance of being left-handed. The same is true for each of the other 409. Since we are now figuring this at equal probability for either hand, the probability at anyone site is not affected by the amino acid before that one in the chain.
To calculate the probability in such a case, the formula to use is the multiplication rule, the heart of probability theory. Mathematician Darrell Huff said it thus: “To find the probability of getting all of several different things, multiply together the chances of getting each one.”
To get the probability of all 410 of the isomeric or handed amino acids of just one protein chain, we must multiply the 1/2 probability which is the case for each position in the chain. It is like flipping a coin 410 times, hoping to get all heads. For each step, there is 1 chance in 2, so we must multiply the 2 by itself (2 x 2 x 2 x . . . x 2). using the figure 410 times. That is 1 chance in 2410. (The exponent means: Multiply together 410 two’s.)
It will be easier to work with this figure if we translate it
to powers of 10 instead of powers of 2. As you know, multiplying 10 by itself is just adding another zero. The equivalent of 2410 is roughly 10123.
The probability that an average-size protein molecule of the smallest theoretically possible living thing would happen to contain only left-handed amino acids is, therefore, 1 in 10123, on the average.
That is a rather discouraging chance. To get the feel of that number, let’s look at it with all the 123 zeros: There is, on the average, 1 chance in –
that all of the amino acids of a particular protein molecule would be left-handed!” (creationsafaris)
Well, it’s a bit annoying when atheists, materialistic people claim to live completely exempt of faith, after seeing these frightening numbers against them!
“Life on Earth is made of “left-handed amino acids (L-amino acids)”. The question of why organisms on Earth consist of L-amino acids instead of D-amino acids or consist of D-sugar instead of L-sugar is still an unresolved riddle. In other words, a major mystery of life on Earth is that organisms are exclusively made up of left-handed amino acids. Therefore, the effort to solve this problem is one of the biggest in research into the origins of life, a subject that remains enveloped in mystery. “ (PhysOrg)
God bless you all!