Burger Jessica L, Jeerage Kavita M, Bruno Thomas J
Applied Chemicals and Materials Division, National Institute of Standards and Technology, Boulder, CO, 80305, USA.
Applied Chemicals and Materials Division, National Institute of Standards and Technology, Boulder, CO, 80305, USA.
Anal Biochem. 2016 Jun 1;502:64-72. doi: 10.1016/j.ab.2016.03.006. Epub 2016 Mar 24.
Mammals are able to perceive and differentiate a great number of structurally diverse odorants through the odorant's interaction with odorant receptors (ORs), proteins found within the cell membrane of olfactory sensory neurons. The natural gas industry has used human olfactory sensitivity to sulfur compounds (thiols, sulfides, etc.) to increase the safety of fuel gas transport, storage, and use through the odorization of this product. In the United States, mixtures of sulfur compounds are used, but the major constituent of odorant packages is 2-methylpropane-2-thiol, also known as tert-butyl mercaptan. It has been fundamentally challenging to understand olfaction and odorization due to the low affinity of odorous ligands to the ORs and the difficulty in expressing a sufficient number of OR proteins. Here, we directly observed the binding of tert-butyl mercaptan and another odiferous compound, cis-cyclooctene, to mouse OR MOR244-3 on living cells by saturation transfer difference (STD) nuclear magnetic resonance (NMR) spectroscopy. This effort lays the groundwork for resolving molecular mechanisms responsible for ligand binding and resulting signaling, which in turn will lead to a clearer understanding of odorant recognition and competition.
哺乳动物能够通过气味剂与气味受体（ORs）的相互作用来感知和区分大量结构多样的气味剂，气味受体是嗅觉感觉神经元细胞膜内发现的蛋白质。天然气行业利用人类对硫化合物（硫醇、硫化物等）的嗅觉敏感性，通过对该产品进行加臭处理来提高燃气运输、储存和使用的安全性。在美国，使用的是硫化合物混合物，但加臭剂包的主要成分是2-甲基丙烷-2-硫醇，也称为叔丁基硫醇。由于气味配体与气味受体的亲和力较低，且难以表达足够数量的气味受体蛋白，因此理解嗅觉和加臭一直具有根本性的挑战性。在这里，我们通过饱和转移差分（STD）核磁共振（NMR）光谱直接观察了叔丁基硫醇和另一种有气味的化合物顺式环辛烯在活细胞上与小鼠气味受体MOR244-3的结合。这项工作为解析负责配体结合和产生信号的分子机制奠定了基础，这反过来将有助于更清楚地理解气味剂识别和竞争。
