Odorivector profile

Most, perhaps all of the odor theories advanced so far made the assumption that the transcription of structureil information encoded in the stimulant molecule into an odor information pattern is an integral process One odorivector (AMOORE, 2) interacts with one receptor site and this interaction resvilts in transcription of all structural components simviltaneously into their corresponding informational modalities. However, observation tells us that olfactory information is inherently complex Ambergris for instance is described (OHLOFF, 3) by six distinctly different notes. This would imply that in an integral process of the periphersil molecular interaction one single neuron has to detect at least six different profiles with six different receptor sites and project the informational modalities intact to the higher centers. 

It furthermore follows that a profile may constitute only a significant part of the overall structure of the odorivector molecule either a shape - the Van der Waals molecular outline proposed by AMOORE - which can degenerate to a molecularly defined plane or it can be a functional group in the traditional sense... 

Odorivector molecviles can contain an almost unlimited number of profiles. Of these are only a few explicit, but with increasing conformational freedom a rapidly increasing number of implicit ones are potentially possible. This raises the question about the number of complementary receptor sites necessary to deal unambiguously and efficiently with the transcription of structural into informational modalities. The concept of multiple profile - multiple receptor sites provides no indication how the actual number of receptor site types covild be deduced. However the minimum number required to encode the total olfactory spectrum perceived by man can be estimated by means of basic principles of information theory. For that a few simple assmptions have to be made ... 

Therefore in any attempt of odor-structure correlation not the total (or overall) structure of the molecule should be considered but the individual contributions of the molecular profiles. Perhaps this could be done by a combination of computer assisted conformational analysis of the odorivectors which would provide information about the nature of the explicit and implicit profiles as well as the probability of the formation of the latter, with multidimensional scaling of the highly processed information the odorivectors deliver. 

Furthermore the odorivectors could be treated the same way, with the same methods, as drug molecules are in QSAR (Quantitative Structure Activity Correlation). A computerized approach to biochemical quantitative structure-activity-correlations was introduced by the HANSCH APPROACH (ll). Definition of all the essential profiles, those capable of being expressed in monoosmatic components, would afford the foundation on which an algorithm for the calculation of odor quality based on the chemical structure of the odorivector conceivably could be designed. 

U) These observed synergistic and antagonistic effects indicate that the regulatory activity has to be encoded in an odorivector present in the mixture, in all probability in the same way as the activators of the detector adei l cyclase - as an "Active Profile"... 

In all of these examples of regulation of transcription of profiles by allosteric regulation of receptor sites by active profiles THE DUAL NATURE OF ODORIVECTORS manifests itself. This is a new principle postulated to be pertinent in all mixtures of odorivectors. In its most extended scope this principle states that all odorivectors have two functions To display their own intrinsic odor and at the same time act as regulator in the odor perception of a copresent odorivector. The latter is achieved by allosteric regulation in a peripheral process. 

That this peripheral interaction of odorivectors is a reality and not Just a postulate resulting from lengthy speculations has been confirmed by statistically significant experimental proof obtained in malodor/"antlmalodor"-interaction studies (l ), and on a more general base, in odor/odor-interactions. These resiolts give implicit proof that specific receptor sites for moleciLLar and active profiles exist. 

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