ULTIMATE COMPUTING - Quantum Consciousness Studies

134 Protein Conformational Dynamics
and hydrogen bonding. Appropriate stimuli including neurotransmitters, voltage
alterations, hormones, ions like calcium, and enzyme substrates can induce
conformational changes within specific proteins. Conformational transduction is
the sensitive link in the mechanism of anesthetic gas molecules (Chapter 7) and
indicates that cognitive functions relating to consciousness depend in some way
on protein conformational regulation. In many cases, proteins “integrate” a
number of factors to result in a new conformation (Figure 6.3). Portions of
proteins may be dynamically active with functional importance. For example,
electron transfer processes such as that which occur in the mitochondrial
production of ATP may rely on vibrational coupling and fluctuations which alter
the distances between electron donors and acceptors. Relative motions of distinct
structural domains within proteins are important in their activities related to
muscle contraction, enzyme activities, antibody functions, and assembly and
activities of supra-molecular structures such as viruses and cytoskeletal proteins.
Dynamic conformational changes of proteins are the dynamics of living
organisms.
Figure 6.3: Protein switching between two different conformational states induced
by binding of ligand, calcium ion, or voltage change. One mechanism proposed
by Fröhlich is that dipole oscillations (e) within hydrophobic regions of proteins
may be a trigger, or switch for the entire protein.
6.3 Proteins and Energy
All movements within cells depend on forces generated by proteins. A typical
allosteric protein can adopt two alternative conformations-a low energy form and
a high energy form that differ by about the energy available from forming a few
hydrogen bonds on a protein surface. The low energy conformation will be
favored by about 1,000 to 1, and the protein will tend to be in this “inactive”
conformation unless influenced by other factors. It can be “pulled” into the active
high energy conformation by binding to a ligand which binds only to the high
energy state. Also, an input of chemical energy can be used to “push” the protein
into the high energy conformation. A common mechanism involves the transfer
and covalent linkage of a phosphate group from biochemical energy sources like
ATP or GTP to one of several amino acid side chains (serine, threonine or
tyrosine) in the protein. This “phosphorylation” can create a distribution of
charged amino acid side chains which are more favorable to one conformation
than another, leaving the nonphosphorylated conformation unavailable. Ten