2-Phenylethyl 1-Thio-beta-D-galactopyranoside TCI P2921

2-Phenylethyl 1-Thio-beta-D-galactopyranoside (TCI P2921), often abbreviated PETG, is a synthetic thiogalactoside. In this compound, a sulfur atom replaces the glycosidic oxygen atom, and the galactose sugar is linked to a 2-phenylethyl group. In biochemistry and glycoscience laboratories, PETG is best known as an inhibitor of the enzyme β-galactosidase. Researchers use it to study how this enzyme works, to control its activity during experiments, and to investigate proteins that recognize galactosides, including the lac operon system in bacteria.

PETG's value comes from its thioglycosidic bond. The C–S linkage is far more resistant to enzymatic hydrolysis than a conventional O-glycosidic bond. As a result, PETG can occupy the active site of β-galactosidase without being broken down, so it acts as a competitive inhibitor that stays stable for the length of an experiment. Its hydrophobic phenylethyl group also increases affinity for the enzyme's binding pocket. This combination of stability and affinity makes PETG a dependable tool for kinetic studies, protein structure work, and carbohydrate recognition research.

In Indonesia, PETG is useful to microbiology, molecular biology, and biochemistry laboratories at universities and research institutions. Researchers studying enzyme mechanisms, bacterial gene regulation, or carbohydrate–protein interactions can use it as a well-defined reference inhibitor in their experimental designs. Because it is supplied under the TCI brand with a clear catalog number and CAS identity, laboratories can document it properly in theses, publications, and internal research records, which supports reproducible results across projects and research groups.

• β-Galactosidase inhibition studies: PETG binds the enzyme's active site without being hydrolyzed, so it works well as a stable competitive inhibitor in activity and inhibition assays.
• Enzyme kinetics research: Because its thioglycosidic bond resists enzymatic cleavage, PETG stays intact during measurements, which makes it suitable for determining inhibition behavior and comparing kinetic parameters.
• Lac operon and bacterial gene regulation studies: As a galactoside analogue, PETG helps researchers investigate how bacterial proteins in the lac system recognize and respond to galactoside structures.
• Protein structure and binding studies: Its stability and the affinity contributed by the hydrophobic phenylethyl group make PETG a useful ligand for examining how galactoside-binding pockets interact with substrates.
• Carbohydrate recognition and glycoscience research: PETG is a defined thiogalactoside probe for studying carbohydrate–protein interactions, because the sulfur linkage resists degradation that would affect ordinary O-glycosides.

• Compound type: synthetic thiogalactoside (2-phenylethyl 1-thio-β-D-galactopyranoside, PETG)

Store PETG in its original, tightly sealed container, following the storage conditions on the TCI label and Safety Data Sheet. Keep the container in a clean, dry place away from moisture, heat, direct sunlight, and incompatible chemicals. Close it promptly after each use to protect the material from humidity and contamination. Handle the compound with standard laboratory personal protective equipment, including gloves, safety glasses, and a lab coat, and avoid creating dust or getting it on skin or in eyes. Weigh and prepare solutions in a clean, well-ventilated area using dedicated spatulas and glassware. Label any prepared solutions with the compound name, concentration, and preparation date. Dispose of waste in line with institutional chemical safety procedures and local regulations.

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