Boolean Logic Gates Realized with Enzyme‐catalyzed Reactions – Unusual Look at Usual Chemical Reactions

Abstract

Research in the area of molecular computing systems, in the general framework of unconventional computing, has received high attention and resulted in rapid progress in formulating signal‐controlled switchable molecules capable to perform Boolean logic operations and basic arithmetic functions. Extension of this research to biomolecular systems allowed sophisticated computational functions much easier than using synthetic molecular and supramolecular species. The advantage of biomolecular systems comparing with synthetic molecular systems is in their complementarity and compatibility allowing easy assembling multi‐component systems from various biomolecules, thus increasing their functional complexity. While DNA‐based computing systems are promising faster computing than Si‐based electronics, at least for solving some combinatorial problems, due to massive parallel operation, enzyme‐based logic systems are less promising for computational applications in their narrow definition. However, they offer novel biosensing and bioactuation features operating in binary Yes/No format. The present review article overviews different kinds of enzyme logic gates exemplified with specific enzymatic reactions/cascades. Motivation for this research and its possible applications are discussed. The review will be helpful to researchers working in this specific area to see the comprehensive collection of logic operations performed by the enzyme reactions. The newcomers to the reviewed area will benefit from the example systems representing various logic functions systematically.

Challenges and Opportunities of Carbon Nanomaterials for Biofuel Cells and Supercapacitors: Personalized Energy for Futuristic Self-Sustainable Devices

“…Outstandingly, compared with the noble-metal catalysts used in conventional fuel cells, the biocatalysts used in the BFCs are efficient and highly selective toward specific fuels. Moreover, advantages of these devices include viability in numerous potential applications, ranging from self-powered biosensors [48,49] to logic devices [50], as well as implantable modular power supplies [51]. The self-powered biosensing applications, based on the utilization of carbon-based BFCs, will be further discussed in Section 4.…”

Boolean Logic Networks Mimicked with Chimeric Enzymes Activated/Inhibited by Several Input Signals

“…Enzymes activated with substrates and co‐substrates, considered as input signals, have been used to mimic various Boolean logic gates . The number of input signals controls the complexity of the Boolean logic operations.…”

“…[17] Enzymes activated with substrates and co-substrates, considered as input signals, have been used to mimic various Boolean logic gates. [18] The number of input signals controls the complexity of the Boolean logic operations. When an enzyme consumes only one input signal (e. g., esterase hydrolyzing an ester) the system can only operate as a single-input logic gate, such as Identity (YES) gate or Inverted Identity (NOT) gate.…”

“…Enzymes consuming two input chemicals (e. g., glucose dehydrogenase reacting with glucose and NAD + ) can mimic many different two-input logic gates (AND, OR, NAND, NOR, XOR, NXOR, etc.). [18] In order to mimic multi-input logic networks [19,20] or reversible logic gates (e. g., Feynman gate, Toffoli gate, Peres gate, etc. ), [21] a few enzymes operating cooperatively are needed.…”

Implication and Inhibition Boolean Logic Gates Mimicked with Enzyme Reactions

“…The negative IMPLY logic operation (Not-IMPLY) corresponds to the Inhibited (INHIB) logic gate, which was already realized in various enzyme-based systems. [11,53,54] The INHIB gate produces the output signal 1 only when the inhibiting signal A appears at its logic value 0 and the value signal B appears at its logic value 1. Otherwise, the gate returns output 0, as shown in the truth table, Figure 2A.…”