Biosensors & Bioelectronics

Biomolecular Mimic Circuit for an Allosterically Regulated Enzyme of Pyrimidine Biosynthetic Pathway

Abstract

R.Vinoth and S. Balaji

A general type of molecular level metabolic control that is common to all living organisms is the feedback inhibition, wherein an increase in the product of a metabolic pathway regulates an enzyme upstream in the cascade by binding to it and decreasing enzyme activity. The de novo pyrimidine biosynthetic pathway provides a specific example for the feedback inhibition. Aspartate transcarbamoylase (ATCase) catalyzes the first step in the biosynthesis of pyrimidines and one of the best understood allosteric enzymes. The structure of ATCase is roughly triangular in shape, similar to the symbol of an op-amp IC. Since most of the enzymatic properties were analogous to the properties of IC, this inspired us to mimic the enzyme (EC 2.1.3.2) with an IC (PIN μ A741CN) in our circuit design. The Michaelis-Menten model, Lineweaver-Burk equation and the equation for the non-inverting amplifier were theoretically related and used for our model. As a result, an electronic feedback circuit was designed and tested. The biomolecular mimic circuit will develop a new level of understanding of the metabolic complexity in the cell.