Arabinogalactan is a biopolymer consisting of arabinose and galactose monosaccharides. AraC acts as an activator in the presence of arabinose. It can be formed by the reduction of either arabinose or lyxose. The conformation is purely determined by the binding of allosteric inducer arabinose. Both the arabinose and galactose exist solely in the furanose configuration. An arabinosyltransferase is a transferase enzyme acting upon arabinose. A classic method for the organic synthesis of arabinose from glucose is the Wohl degradation. Recently, engineered yeasts have been described efficiently fermenting xylose, and arabinose, and even both together. Cytosine arabinoside combines a cytosine base with an arabinose sugar. As explained above, P is regulated by the addition and absence of arabinose. It is usually distinguished from "B. pseudomallei" by its ability to assimilate arabinose. Foods that contain arabinose are usually designed for prediabetic and diabetic patients. "B. breve" strains can ferment mannitol and sorbitol, but not arabinose or xylose. When arabinose is absent, cells do not need the "ara" products for breaking down arabinose. They can both oxidise arabinose, but only "S. liquefaciens" can ferment arabinose in peptone water.