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

FATTY ACIDS, PHOSPHOLIPIDS AND BIOMEMBRANES

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Fatty Acids and Phospholipids

Oxygen was needed to convert glucose into acetic acid, acetic acid was needed to be coupled together to produce long chains and hydrogen was needed to reduce oxygen atoms off the chains and yield a variety of long-chain fatty acids.58,59

Both hydrtogen-atom-saturate and unsaturated fatty acids combine with phosphate and amino-alcohols to produce phospholipids which exist in high and low energy forms.

Some fatty acids, like stearic, were totally saturated with a maximum number of hydrogens on the chains while others, like oleic, were unsaturated with two or more hydrogens missing and double bonds between the carbons. At the same time, molecules like isoprenol were produced from acetic acid and converted into an array of vitamin and cofactor molecules containing series of double bonds which could absorb wavelengths of light and quanta of energy.59

In alkaline media, fatty acids are surfactant soaps – they migrate spontaneously to the surface of water with their lipid tails toward the air and their anionic heads toward the water - hydrogen-bonding with water molecules at angles which do not permit linear element formation. By disrupting the surface-hydration order, surface tension is reduced, interfacial bonding is weakened and bubbles form. In contact with oils, fatty acids surround the oil molecules with their tails toward the oil and their heads toward water – oil molecules are emulsified as negatively-charged microdroplets.58

However, as enzymes formed which could attach glycerin, phosphate ions and amino alcohols (like the amino-alcohol choline) to the heads of the fatty acid molecules, an entirely new class of molecules was produced.59 Phospholipids (like lecithin) assembled on the surface of water in the same manner as fatty acids, but, instead of disrupting hydration linearization, their heads were “zwitterions” with positive and negative charges the same distances apart as the dielectric trimers in surface of water.60 Instead of disrupting linear order, their heads reinforced the formation of transient linear elements of hydration - they increased surface tension and formed planar double layer membranes with their dynamic tails directed toward each other in the center and their dipolar heads facing linearly-ordered water on the both sides.59, 60For the first time, these double layers could circle around and form spherical cells with components inside separated from those outside. For the first time, reproductive life no longer had to be carried out by virus-like particles but by cellular forms like bacteria: cellular forms with membranal walls which could encompass photosynthetic particles, ribosomal particles, ATP-producing particles and reproductive code-storing particles.62

Phospholipid Membranes

In fact, the most abundant molecular form of lecithin has one saturated chain, like steric acid, and one unsaturated, like oleic acid.59 As illustrated previously, the central cis double bond in the oleic acid molecule disrupts linear regularity in the chain and induces it to adopt multiple conformations – to form kinks and adopt dynamic rotary motion.60

Large head groups on the phospholipids permit them to exist in both alpha and beta forms in bilayer membranes and provide insertion of proteins of many shapes.

Large head groups on the phospholipids permitted hydrocarbon tails below them to absorb energy and be converted from straight beta states to dynamic alpha states.60 For a number of reasons, bilayers in multiple states exhibited extremely-important properties.

First: transitions from beta to alpha involved the absorption of significant quanta of energy in the lipid chains with an increase in surface area. By shifting from expanded alpha to contracted beta states, spaces could be opened in the surface to permit lipid molecules, like fats and polypeptide coils with lipid surfaces, to move spontaneously into membranes and be incorporated into functional complexes.

Second: as ATP molecules in membranal proteins hydrolyzed, for example during discharges of nerve cells, the released energy compressed lipids from alpha to beta states - lipid energy moved rapidly into surface water to decrease hydration order, decrease surface tension and open transport pores for the movement ions and molecules in and out. ATP hydrolysis in membranes permitted nerve and muscle cells to communicate, to feed, to breath, to live.21

Third: by increasing the degree of unsaturation in lipid chains, transition temperatures from beta to alpha could be decreased. For example, if the temperature around bacteria is lowered, they synthesize fatty acids with more double bonds to maintain mobility in their membranes. The same shift in fatty acid synthesis may occur in humans as external temperatures change.

Fourth: by altering the head groups on phospholipids, interactions with surface water, binding with surface molecules and temperature transitions from beta to alpha could be dramatically altered. In fact, phospholipids with large head-groups, like phosphoinositols, may provide surface storage sites for ions like sodium and calcium.

Last, but not least: by inserting proteins with conical shapes into membranes, cells could produce hormone and neurotransmitter storage bubbles, permit unions with other cells, produce cell divisions and, at times, produce protective sheath-layers around them.

For the first time, vital organelles, like ribosomes and replication systems for DNA could be protected from each other by their own, specialized phospholipid membranes. Ribosomes could bind directly to membranes and insert proteins for transport and energy production. A brand New World of Cellular Life was brought forth by the formation of phospholipids and biomembranes.61,62

What often is forgotten is that, when ATP molecules hydrolyze in the lipid zone, the quantized units of energy released produce waves of contraction from alpha to beta – sometimes to form bonds, sometimes to break bonds, sometimes to power transport – all in a coordinated fashion without connecting ATP molecules directly to the proteins or nucleic acids involved. Phospholipid membranes are amazing!

Phospholipid/Cholesterol Membrane

Although many types of membranes developed to perform numerous functions, they all appear to have assembled based on the same TLH-properties of surface hydration order/disorder which had directed the formation of proteins. In fact, it appears that the dynamic surface linearization of water not only selected functional molecules, it selected functional membranes as well. For example, if we look closely at the structure of plasma membranes which encompass many cells, we find that distances through the lipid zone correspond to hydrogen-bonded segments of nineteen water molecules: nine on each side, equal to the length of the dynamic alpha-lipid chains, and one in the middle for the intersection of the chains.

Phospholipids, cholesterol, protein coils and linear segments of covalently-bonded water molecules all define 40.5 Angstroms as the harmonic width for most cell membranes.

This “Fluid Mosaic Structure” for membrane was proposed by Singer and Nicolson back in 1972,60 the same year that Kirschner and Casper published the electron scattering (ES) and neutron scattering (NS) curves rabbit nerve cell membrane.63 ES peaks occur wherever charged groups are on both sides of the membrane; NS peaks occur wherever there is water. As expected, there is little or no water or ions in the center of the membrane and both curves peak where one would expect based on the TLH Model of membranal phospholipids in their alpha energy state. The helical, coiled protein shown was isolated from a red blood cell with the same type of phospholipid membrane. Note that the polar, charged oxygen and nitrogen atoms on the protein coil are where they would be expected and that most side chains on peptides in the center of the membrane are hydrophobic.

Since water had to pass through pores in membranes to integrate processes on both sides, it should not be surprising that the average length of the lipid zone corresponds to a specific number of linearly-oriented water molecules or that the fatty-acid segments of phospholipid molecules in these plasma membranes correspond to linear segments of nine water molecules. In fact, the molecule with four rings complexed with lecithin in the model above is cholesterol - again, with a length corresponding to a linear segment of nine water molecules. Although the illustration refers to the cholesterol/lecithin combination as a “complex,” they exist in equal proportions in membranes but both are in dynamic motion – moving in and out of hydrogen-bonding relationships on the surface with lipid chains in dynamic motion and the cholesterol molecule in rotary motion to maintain the alpha state. Insertion of proteins composed of multiple coils into membranes, restricts motion in lipid chains around them but provides the thermal energy they need to function efficiently and move from one conformational state to another.61

Of critical importance is the realization that the mean dimension of 40.5 angstroms between oxygen atoms on both sides of the membrane, not only corresponds to coupled lengths of phospholipid chains and 17 hydrogen-bonded water molecules across the lipid zone (17x4,5A) but to 27 peptides in a tight coils (27x1.5A) across the membrane. Thus, 40.5 angstroms is a “harmonic” distance permitting uniform integration of motions and functions between proteins, phospholipids and water - the same type of quantized length in transient linear elements of water which provide for smooth integration of motion between polar and ionic atoms – the same type of quantized lengths which regulate the spontaneous folding, assembly and cubic patterning of proteins and nucleic acids.

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