Description
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 PBAD promoter. The PBAD 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 Specifications 
 L-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