Molecular Creation (logo) A Story of Natural Molecular Evolution from Atoms and Water to the living Cell

BIOMOLECULAR EVOLUTION

SUGARS AND POLYSACCHARIDES

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Sugars

Although we have been speaking about pure water and pure saline water, primordial seas were far from “pure. If you can imagine turning all the plants and animals on earth into the small molecules from which they came and putting them in the sea - it would have been a soup of toxic chemicals interacting with each other in billions of different ways. Many of the chemicals which arrived from space and produced by solar-activation were relatively stable in water, but some were not. Formaldehyde, for example, once dissolved in water, becomes highly reactive. In the presence of calcium, hydroxide and cyanide ions, formaldehyde molecules (CH2O) couple together spontaneously to form a variety of sugars with the formula (CH2O)x.22

If formaldehyde molecules are dissolved in water in the presence of calcium, hydroxide and cyanide ions they spontaneously assemble to produce a variety of sugar molecules.

Glucose, Arabinose, Ribose and Fructose are only four of the many sugar molecules produced when formaldehyde molecules couple together - all of them in equilibrium - all of them converting back and forth between each other.23 However, as illustrated above, when the chains reach five to six units in length, they circle around and form rings. Sugars in this cyclic form are more stable and no longer react as readily with formaldehyde to yield longer chains. In fact, glucose, because of its spatial structure, was (and is) one of the most stable of all sugars in aqueous medium.23 Thus, glucose, which is the most abundant molecular form on earth today and the primary source of carbon and energy within living cells, might well have been the most abundant molecule in the early seas. It would have formed spontaneously in alkaline tidal pools containing formaldehyde, calcium and cyanide and might well have accumulated rapidly.

In fact, glucose, C6H1206, is the carbon and spatial analog of hexagonal water, H12O6, the same hexagonal unit which forms spontaneously on water-ordering hydrocarbon surfaces. In fact, glucose is synthesized today by the same reaction involving formaldehyde. In photosynthesis, carbon dioxide is reduced to formaldehyde which is then coupled together catalytically to produce glucose. However, formaldehyde is an extremely reactive chemical and, in the presence of ammonia and other chemicals from space, would have spontaneously produced an incredible variety of molecular forms.19 But, glucose would have been produced so readily, with only common ions as catalysts, that it merits special attention. In order to do that, the molecule must be viewed as ball and stick models which reduce the size of the atoms and omit the hydrogens.

In its solid crystalline form, glucose exists as the alpha-D form with the hydroxyl oxygen on carbon 1 perpendicular to the ring but, when dissolved in water, it flips into the plane.

In its solid crystalline form, glucose exists as the alpha-D form with the hydroxyl oxygen on carbon 1 perpendicular to the ring but, when dissolved in water, that oxygen flips back and forth to the beta position in the plane of the ring. As will be seen shortly, the alpha form might have played an important role in the early development of natural molecules.

However, there is another form of glucose which would have been produced from formaldehyde in solution in equal amounts to D-glucose - it is L-glucose. At first glance, this beta-L form looks like alpha-D but, in fact, it is the mirror image of beta-D - like your right and left hand. For some unknown reason, nature produces only the D, right-hand form of glucose and only one form of most other natural molecules. All sorts of explanations have been advanced to explain how this could have happened but none are really satisfactory. Of course, for creationists, only one form of glucose would have been produced but, for the evolutionist, it is a dilemma. One possibility, which appears not to have been advanced, is that a polymer of glucose may have been involved in this next step of spontaneous production.

Starch

If an aqueous solution containing glucose is evaporated to dryness and heated, the molecules dehydrate and spontaneously chemically bond together by alpha-type linkages to produce a variety of polysaccharide polymers. If dissolved again in water, heated, dried and heated multiple times, polymers with uniform, internally hydrogen-bonded structures would have accumulated at the expense of the others. Those that did not form stable structures in water would have broken down and hydrolyzed back to glucose. It turns out that one of the most stable polysaccharide polymers is the one shown below - today it is produced enzymatically in plants and animals - it is starch.36

When glucose is heated, it combines by alpha-linkages to form starch coils with hydrogen-bonding oxygen atoms on the outside and an anhydrous core.

If, by chance, eight D-glucose molecules bonded together with alpha linkages before L molecules, they would have coiled around and formed an internally hydrogen-bonded D helical unit. On repeated drying, heating, dissolving and heating, this first short D helical segment would have selectively bound more D-glucose molecules to form an extended D coil. If the coil then broke into shorter units, each one would have served as a seed to produce more D-starch. Although it may have taken many years for the first coordinated D-coil to form, once it formed, the process might well have proceeded rapidly to yield huge gelatinous masses of straight and branched D-starch molecules, as well as a number of other D-polysaccharides that were stable to hydrolysis. Today, D-starch is produced by enzymes and is the most abundant polysaccharide on earth – it stores glucose molecules in both plants and animals.

Cellulose

D-Cellulose, which is produced from D-glucose with a beta rather than alpha linkage, most likely was not present in the early world because enzymes are required for its synthesis.37  As you can see, it forms flat linear blades, broad sheets and filaments which serve as the structural components of leaves and wood.

Cellulose is composed entirely of beta-linkages between the glucose units to form flat blades and sheets with relatively hydrocarbon surfaces.

Surface Hydration Order and Disorder

Now, if we view the surface hydration of beta-D-glucose with respect to the concept ofTransient Linear Hydration as presented above, it is a flat planar molecule with two of its six oxygen atoms in perfect positions to hydrogen-bond with transient linear elements of water above the molecule and two below the plane of the ring.

Although the glucose molecule does not form stable hydrogen bonds with surface water, by hydrogen-bonding with linearly-ordered water molecules, it has surfactant properties.

However, water molecules in the plane of the glucose molecule are held in positions by hydrogen-bonding that do not support linear hydration order, they disorder adjacent water and provide for freedom of the molecule to move rapidly in that plane. Thus, even though glucose molecules do not bind with adjacent water molecules to form stable hydrates,38 by inducing the formation of transient linear elements of hydration above and below the molecule, they would be expected to exhibit surfactant properties - to spontaneously move to water-ordering regions on the outer surfaces of membranes where they can displace trimers of water in membranal proteins and be transported into cells. Based on the TLH hypothesis, it is the unique structure of the glucose molecule and the way its alcoholic groups bind to water on its surfaces and to polar atoms within proteins which guide it spontaneously into transport and functional sites.

If, now, we look at starch molecules, either in their tubular or filamentous forms, the central cores are relatively hydrophobic - water molecules do not bind inside. On the other hand, alcohols on the outer surfaces of the coils are not in orderly arrangements - they disorder water permitting the tubules and filaments to be extremely flexible and highly hydrated with water molecules in dynamic random-motion around them. In contrast, cellulose blades and sheets are flat with water ordering on both sides. They are relatively ridged and spontaneously assemble side by side to release ordered water and form flat structural units with the strength to produce the long fibrous structural elements. Most cellulose fibers are covered with lignin molecules which coat them with polar groups to increase disorder and solubility.

Thus, by mimicking the spatial properties of hexagonal water, D-glucose most likely directs its own motion adjacent to surfaces and produces two polymers with entirely-different water-bonding and structural properties. As we shall see, based on the TLH hypothesis, all natural molecules within living cells perform their vital functions by regulating the orientation and order/disorder properties of surface water.8, 29

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