L-Arabinose is an arabinose isomer widely found in nature, while D-arabinose is less common. L-Arabinose is a constituent of many biopolymers that make up plant cell walls.

This monosaccharide is often used in cell culture media, serving as a bacterial carbon source, and can be used to distinguish between bacteria based on their fermentation abilities.

L-Arabinose, in the absence of glucose, induces transcription of the ara operon in E. coli that encodes L-arabinose catabolizing enzymes. It does this by binding to the AraC protein and activating the P_BAD promoter. The P_BAD promoter is used in plasmid vectors as a switch for protein expression that can be turned on by L-arabinose or turned off by addition of glucose.

Product SpecificationsL-Arabinose;L-Ara;

MOLECULAR BIOLOGY GRADE

Formula: C₅H₁₀O₅

MW: 150.13 g/mol

Merck Index: 13,765

Storage/Handling: Store at room temperature.

PubChem Chemical ID: 854

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