L-Arabinose is the naturally occurring isomer and constituent of plant polysaccharides. Most bacteria contain an inducible arabinose operon which codes for a series of enzymes and transporters that allows L-arabinose to be used as the sole carbon source in microbial culture. L-Arabinose is the naturally occurring isomer and constituent of plant polysaccharides. Most bacteria contain an inducible arabinose operon which codes for a series of enzymes and transporters that allows L-arabinose to be used as the sole carbon source in microbial culture. A ubiquitous naturally occuring saccharide