Limits...
Life depends upon two kinds of water.

Wiggins P - PLoS ONE (2008)

Bottom Line: Energy transduction is neither possible and nor necessary.Bioactive enantiomorphs partition into low density water in which they polymerise spontaneously.The simplified model of water has great explanatory power.

View Article: PubMed Central - PubMed

Affiliation: Mairangi Bay, Auckland, New Zealand. p.wiggins@paradise.net.nz

ABSTRACT

Background: Many well-documented biochemical processes lack a molecular mechanism. Examples are: how ATP hydrolysis and an enzyme contrive to perform work, such as active transport; how peptides are formed from amino acids and DNA from nucleotides; how proteases cleave peptide bonds, how bone mineralses; how enzymes distinguish between sodium and potassium; how chirality of biopolymers was established prebiotically.

Methodology/principal findings: It is shown that involvement of water in all these processes is mandatory, but the water must be of the simplified configuration in which there are only two strengths of water-water hydrogen bonds, and in which these two types of water coexist as microdomains throughout the liquid temperature range. Since they have different strengths of hydrogen bonds, the microdomains differ in all their physical and chemical properties. Solutes partition asymmetrically, generating osmotic pressure gradients which must be compensated for or abolished. Displacement of the equilibrium between high and low density waters incurs a thermodynamic cost which limits solubility, depresses ionisation of water, drives protein folding and prevents high density water from boiling at its intrinsic boiling point which appears to be below 0 degrees C. Active processes in biochemistry take place in sequential partial reactions, most of which release small amounts of free energy as heat. This ensures that the system is never far from equilibrium so that efficiency is extremely high. Energy transduction is neither possible and nor necessary. Chirality was probably established in prebiotic clays which must have carried stable populations of high density and low density water domains. Bioactive enantiomorphs partition into low density water in which they polymerise spontaneously.

Conclusions/significance: The simplified model of water has great explanatory power.

Show MeSH

Related in: MedlinePlus

Elution of 20 mM of each of KD-glutamate and KL-glutamate on a Dowex cation exchange resin in its Na+ form.
© Copyright Policy
Related In: Results  -  Collection


getmorefigures.php?uid=PMC2170473&req=5

pone-0001406-g007: Elution of 20 mM of each of KD-glutamate and KL-glutamate on a Dowex cation exchange resin in its Na+ form.

Mentions: Columns of both anion and cation exchangers, separated enantiomers with and without supporting solutes. Figure 7 shows an example in which D- and L-Kglutamate were separated on a Dowex cation-exchange resin. Since the microenvironments surrounding charged groups stabilized both LDW and HDW, both enantiomers were, to some extent retained on the column. The pattern of elution changed drastically when the counter ion on the resin was changed.


Life depends upon two kinds of water.

Wiggins P - PLoS ONE (2008)

Elution of 20 mM of each of KD-glutamate and KL-glutamate on a Dowex cation exchange resin in its Na+ form.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC2170473&req=5

pone-0001406-g007: Elution of 20 mM of each of KD-glutamate and KL-glutamate on a Dowex cation exchange resin in its Na+ form.
Mentions: Columns of both anion and cation exchangers, separated enantiomers with and without supporting solutes. Figure 7 shows an example in which D- and L-Kglutamate were separated on a Dowex cation-exchange resin. Since the microenvironments surrounding charged groups stabilized both LDW and HDW, both enantiomers were, to some extent retained on the column. The pattern of elution changed drastically when the counter ion on the resin was changed.

Bottom Line: Energy transduction is neither possible and nor necessary.Bioactive enantiomorphs partition into low density water in which they polymerise spontaneously.The simplified model of water has great explanatory power.

View Article: PubMed Central - PubMed

Affiliation: Mairangi Bay, Auckland, New Zealand. p.wiggins@paradise.net.nz

ABSTRACT

Background: Many well-documented biochemical processes lack a molecular mechanism. Examples are: how ATP hydrolysis and an enzyme contrive to perform work, such as active transport; how peptides are formed from amino acids and DNA from nucleotides; how proteases cleave peptide bonds, how bone mineralses; how enzymes distinguish between sodium and potassium; how chirality of biopolymers was established prebiotically.

Methodology/principal findings: It is shown that involvement of water in all these processes is mandatory, but the water must be of the simplified configuration in which there are only two strengths of water-water hydrogen bonds, and in which these two types of water coexist as microdomains throughout the liquid temperature range. Since they have different strengths of hydrogen bonds, the microdomains differ in all their physical and chemical properties. Solutes partition asymmetrically, generating osmotic pressure gradients which must be compensated for or abolished. Displacement of the equilibrium between high and low density waters incurs a thermodynamic cost which limits solubility, depresses ionisation of water, drives protein folding and prevents high density water from boiling at its intrinsic boiling point which appears to be below 0 degrees C. Active processes in biochemistry take place in sequential partial reactions, most of which release small amounts of free energy as heat. This ensures that the system is never far from equilibrium so that efficiency is extremely high. Energy transduction is neither possible and nor necessary. Chirality was probably established in prebiotic clays which must have carried stable populations of high density and low density water domains. Bioactive enantiomorphs partition into low density water in which they polymerise spontaneously.

Conclusions/significance: The simplified model of water has great explanatory power.

Show MeSH
Related in: MedlinePlus