It’s unlikely that you’ve heard of a German organic chemist named Emil Fischer. The 1902 winner of the Nobel Prize in Chemistry was the first to discover and synthesize purines, or chemical compounds commonly found in food and drinks. It is Fischer we have to thank for the discovery of the world’s most commonly used psychoactive drug, and member of the purine family, caffeine


But Fischer’s work was not limited to the discovery and synthesis of purines. He also studied the molecular structure of enzymes - or biological molecules (proteins) that initiate complex chemical reactions. All the way back in 1894, Fischer hypothesized that these chemical reactions begin when a substrate (the substance on which an enzyme acts) binds to the active site on an enzyme. 


Confused yet? Think of it this way. When a substrate and enzyme meet on the active site, it forms a substrate complex. Enzymes, it turns out, are picky. They won’t attach tidily to just any molecule. And without that fit, catalysis - or the process of making something new by breaking it down or combining it with another molecule - cannot occur. And this fit is important because enzymatic activity affects everything that happens in our bodies, like breathing, digestion, and muscle and nerve function. 


When an enzyme and the substrate fit together just right, it turns into what Fischer named the Lock and Key Theory, which goes like this: the lock is the enzyme, while the key is the substrate. Enzymatic activity can only occur when the correct key (substrate) fits properly into the keyhole (active site) of the lock (enzyme). Just like with our own doors, the wrong key won’t open it, no matter which direction we turn it or how gently or hard we jiggle it. 


The Lock and Key Theory plays an important role in the endocannabinoid system (ECS), a physiological complex charged with creating homeostasis - or a harmonious balance among bodily systems. It wasn’t until 1988 that researchers at the St. Louis University School of Medicine discovered that humans have receptor sites throughout the body, including the brain, immune cells, organs, and connective tissues that make up the ECS. 


The endocannabinoid system is so named because these receptors form a lock and key relationship with the compounds found in cannabis, like THC, which is well known for its euphoric effects. 


More than 100 cannabinoids have been identified within Cannabis plants, though thus far THC and CBD are the most researched. There are also as many as 12 different types of receptors within a human body that are currently being researched as part of the endocannabinoid system. The two that have been fully confirmed by the scientific community so far are called “CB1” and “CB2”. 


As the science and research of cannabinoids and the receptors progresses, we expect to find better matches between the keys and the locks. A future with all-natural keys to unlocking your wellness.