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SUMMARY
Animals and plants "communicate" with each other, and with their environments, via common ion, free radical, and
molecular messengers which function by electrochemical energy-transduction mechanisms. Such mechanisms depend upon
the reversible sulflwdryl-disulfide redox couple in receptor and energy-transducer proteins to convert quantitatively messeaget-based
energy states from the environment into altered membrane potentials and/or second messengers which may serve
as signals in the elicited cell, and between it and other cells in an organism. Receptor and energy-transducer proteins are
associated with the plasma membrane which surrounds each living cell. Within biological constraints, the conversion of a
molar-messenger energy state into a redox-based energy state in the sulfhydryl-disulfide receptor and energy-transducing
protein in the plasma membrane is linear (i.e., quantal). This means that messenger-borne energy from the environment is
converted to informational energy (i.e., units) by the perceiving cell.
Many entomologists and chemical ecologists have used the electroantennogram (i.e., EAG) to detect compounds
from the environment which alter the behavior of insects. In using this classical technique, the experimentalist is measuring
change in the energy (e.g., dendritic-membrane potential) state in the primary peripheral chemosensory neurons which are
specially "housed and exposed to the external environment" within the antenna of the insect. The experimental use of the
EAG and the correct prediction, thereby, of the resultant behavioral change elicited in the whole, live insect constitutes
scientific proof that the information necessary for alteration of the behavior of the whole insect can be encoded in the primary
peripheral chemosensitive neuron. This encoding of energy into information is dependent upon the element 'sulfur', and
especially its readily reversible sulfhydryl (i.e., thiol, -SH) / disulfide (i.e., -S-S-) redox couple. This encodement of chemical-messenger
energy into biologically useful information is blocked (or otherwise altered) in the intact cell or whole
organism by the application of biological concentrations of reagents which react specifically with sulfhydryls and/or disulfides
in proteins in plasma inembrane. Recent research has proven that this transduction of environmental energy into
biologically useful inflmnation also occurs in plant cells. Thus, the sulfhydryl / disulfide-dependent Environmental Energy
Exchange Code is supported by extensive scientific findings from both animal and plant reahns.
The unique atomic attributes of the element 'sulfur' for fulfilling this vital role in the conversion of environmental
energy into biologically useful infornaation figrall cells were clearly described by Wald (1969). It is fortunate that scientists
can now readily test the role of sulfur, and especially the sulthydryl / disulfide redox couple, in the exchange of environmentally
based energy into information in any living cell. Chemical ecologists seem especially fortunate in this regard through
their frequent familiarity with the EAG and other electrophysiological techniques for experimentation. We have also shown
the usefulness of classical electrochemical (e.g., dropping-mercury-electrode polarography) techniques for asking questions
about the roles of sultur and its derivatives in the proposed Environmental Energy Exchange Code. Further experiments on
this exciting energy-exchange interface between living cells, organisms, and their vital environments should yield data which
significantly improve our abilities to quantify environmental influences on the expressions of phenotypes by genomes, and on
the functionalities and longevities of such phenotypes.
ACKNOWLEDGEMENTS
Research reported here from the author's laboratories was supported partially by the College of Agricultural and Life
Sciences, University of Wisconsin, Madison, Wisconsin, USA; in part by numerous research grants from the U.S. National
Science Foundation and the U.S. National Institutes of Health; and in part by U.S. Hatch Projects 3040 and 3419, McIntire-
Stennis Project 3127, and USDA Competitive Grants 84-CRCR-1-1501 and 88-37153-4043.
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