Molecular Interactions between an Enzyme and Its Inhibitor for Selective Detection of Limonene

Area of Science:

• Biochemistry
• Chemical Sensing
• Molecular Interactions

Background:

• Enzyme inhibition is crucial for pharmaceuticals and pesticides.
• Applying enzyme inhibition to odorant sensing is limited due to unclear mechanisms.
• Acetylcholinesterase (AChE) is a key enzyme with known inhibitory interactions.

Purpose of the Study:

• To propose a new strategy for selective odorant detection using inhibitor-specific enzymes.
• To elucidate the interaction mechanism between AChE and limonene for odorant sensing.
• To develop a quantitative method for detecting limonene using enzyme inhibition.

Main Methods:

• Molecular dynamics simulations to analyze AChE-limonene interactions.
• Experimental validation using an ion-sensitive field-effect transistor (ISFET).
• Quantitative analysis of limonene concentration and specificity testing against other odorants.

Main Results:

• Limonene selectively binds to AChE, inhibiting its activity towards acetylcholine (ACh) hydrolysis.
• The degree of AChE inhibition correlates with limonene concentration.
• Quantitative detection of limonene achieved with a 5.7 μM detection limit.
• Successful differentiation of limonene from other odorants like pinene and perillic acid.

Conclusions:

• The proposed enzyme inhibition strategy enables highly selective odorant detection.
• This method provides a quantitative approach for sensing specific odorants.
• The findings support the development of miniaturized, rapid odorant-sensing systems.