Division of Neuroscience, Biomedical Sciences Research Centre "Alexander Fleming," Vari 16672, Greece.
Department of Chemical Sciences School of Chemical Engineering, National Technical University of Athens, Athens 15780, Greece.
eNeuro. 2017 Oct 31;4(5). doi: 10.1523/ENEURO.0049-17.2017. eCollection 2017 Sep-Oct.
A remarkable feature of olfaction, and perhaps the hardest one to explain by shape-based molecular recognition, is the ability to detect the presence of functional groups in odorants, irrespective of molecular context. We previously showed that trained to avoid deuterated odorants could respond to a molecule bearing a nitrile group, which shares the vibrational stretch frequency with the CD bond. Here, we reproduce and extend this finding by showing analogous olfactory responses of to the chemically vastly different functional groups, thiols and boranes, that nevertheless possess a common vibration at 2600 cm. Furthermore, we show that do not respond to a cyanohydrin structure that renders nitrile groups invisible to IR spectroscopy. We argue that the response of to these odorants which parallels their perception in humans, supports the hypothesis that odor character is encoded in odorant molecular vibrations, not in the specific shape-based activation pattern of receptors.
嗅觉的一个显著特征，也许是最难用基于形状的分子识别来解释的特征，是能够检测到气味剂中官能团的存在，而不管分子环境如何。我们之前表明，经过训练避免氘化气味剂的 可以对带有腈基的分子做出反应，腈基与 CD 键具有相同的振动拉伸频率。在这里，我们通过展示 对化学性质迥异的官能团（硫醇和硼烷）的类似嗅觉反应来再现和扩展这一发现，尽管它们具有相同的 2600cm 处的振动。此外，我们表明 不会对氰醇结构做出反应，氰醇结构使腈基在红外光谱中不可见。我们认为， 对这些气味剂的反应与人类对它们的感知相平行，支持了这样一种假设，即气味特征是由气味剂分子振动编码的，而不是由受体的特定基于形状的激活模式编码的。
