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arXiv · 1303.6993

The coupling of thermodynamics with the organizational water-protein intra-dynamics driven by the H-bonds dissipative potential of cluster water

Alfred Bennun
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Abstract

The Red cell-Hb-CSF functions as a sensor adapting response to Hb heterotropic equilibriums. At the lungs O2 and Mg2+, each one increasing affinity for the other stabilize the relax (R) form [(O2)4Hb(Mg)2].(H2O)R. At tissue level, the inclusion of H+ and 2,3-DPG excludes O2 and Mg2+ to stabilize the tense (T) form 2,3-DPG-deoxyHb-(H2O)T. Both senses are integrated into a cycle T into R and R into T, without involving a direct reversal. The dissipative potential of water cluster (H2O)n interacts with the hydrophilic asymmetries of Hb, to restrict randomness of the kinetic sense implicated in a single peak for activation energy (Ea). The hydration shells could sequence an enhanced Ea into several peaks, to sequentially activate transitions states. Hence, changes in dipole state, sliding, pKa, n-H-bonds, etc., could became concatenated for vectoriality. (H2O)n by the loss of H-bonds couple with to the hydration turnover of proteins and ions to result in incomplete water cluster (H2O)n*, with a lower-n. (H2O)n* became a carrier of heat/entropy into the cerebrospinal fluid (CSF) which has to be replaced 3.7 times per day. OxyHb formation involves sliding-down of alpha vs beta chains, to shift alpha1 and alpha2 Pro 44 into allowing the entrance of a fully hydrated [Mg.(H2O)6](H2O)12-14(2+) (or Zn2+) into the hydrophilic beta2-alpha1 and beta1-alpha2 interfaces. OxyHb pKa of 6.4 leads to H+-dissociation increasing negative charge of R-groups. This at beta2-alpha1 sequence two tetradentate chelates, first an Mg2+, bonding with beta2 His 92 and a second Mg2+ with alpha1 His 87, to cooperatively release hindrance. The interconversion of oxy-to-deoxyHb, pKa=8, leads to the amphoteric imidazole to became positively charged and proximal histidines return into hindrance position, releasing the incomplete hydrated Mg.(H2O)inc(2+) and O2 into CSF.

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Alfred Bennun. 2013-03-27. The coupling of thermodynamics with the organizational water-protein intra-dynamics driven by the H-bonds dissipative potential of cluster water. https://arxiv.org/abs/1303.6993

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