S

Substrate

E + S ⇌ ES → E + P; Km = ([E][S])/[ES]
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Quick Reference
Formula / NotationE + S ⇌ ES → E + P; Km = ([E][S])/[ES]
Also Known AsEnzyme substrate, reactant (biochemical), ligand (enzyme context)

What is Substrate?

The molecule upon which an enzyme acts in a biochemical reaction. The substrate binds to the enzyme's active site, forming an enzyme-substrate complex. The enzyme catalyzes conversion of the substrate to product. Substrate concentration affects enzyme reaction rate (Michaelis-Menten kinetics).

Formula & Notation

E + S ⇌ ES → E + P; Km = ([E][S])/[ES]

Other Names / Synonyms: Enzyme substrate, reactant (biochemical), ligand (enzyme context)

Properties & Characteristics

A substrate is the molecule upon which an enzyme acts, binding to the enzyme's active site to undergo a chemical transformation. The enzyme-substrate complex forms transiently before products are released. Substrate specificity is determined by the complementary shapes and interactions of the active site and substrate (lock-and-key or induced fit models). Substrate concentration affects reaction rate as described by Michaelis-Menten kinetics.

Uses & Applications

Understanding substrate-enzyme interactions guides the design of enzyme inhibitors used as drugs. Substrate specificity is exploited in biosensors and diagnostic assays. Industrial biocatalysis uses enzymes with specific substrates to produce chemicals and pharmaceuticals.

Safety Information

Some substrates of industrial enzymes are toxic or mutagenic compounds. Handling enzyme substrates in research requires awareness of their specific hazards.

Always consult the SDS/MSDS before handling any chemical. This information is for educational purposes only.

Key Facts

Term Substrate
Formula E + S ⇌ ES → E + P; Km = ([E][S])/[ES]
Synonyms Enzyme substrate, reactant (biochemical), ligand (enzyme context)

Frequently Asked Questions

The molecule upon which an enzyme acts in a biochemical reaction. The substrate binds to the enzyme's active site, forming an enzyme-substrate complex. The enzyme catalyzes conversion of the substrate to product. Substrate concentration affects enzyme reaction rate (Michaelis-Menten kinetics).

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Editorial standards: Chemical data is sourced from peer-reviewed literature, CAS Registry, NIST WebBook, and PubChem. Safety information reflects guidance from OSHA, ECHA, and IAEA. For educational purposes only — always consult official SDS documentation and qualified professionals before handling chemicals.