Xylose Metabolism and Transport in Bacillus subtilis and Its Application to D-Ribose Production.

Abstract

Xylose is a five-carbon sugar and the second abundant mono-saccharide in lignocellulosic biomass. Xylose is not only a sugar substitute by itself, but also a good carbon source for the microbial and enzymatic synthesis of various valuable biomaterials. Most microorganisms are able to uptake and consume xylose as a sole carbon source because they possess specific transport systems and metabolic enzymes. Bacillus subtilis is a representative Gram-positive bacterium commercially used for enzyme and food production. Even though B. subtilis is popular in genetic and protein engineering, its application for metabolic engineering has been limited. Meanwhile, D-ribose is a five-carbon sugar and essential component in nucleotides, ATP, NAD, coenzyme A and so on. It boosts healthy effects on the human body such as enhancement of muscle performance and tolerance to myocardial ischemia. To produce D-ribose from xylose in B. subtilis, a comprehensive review on xylose metabolic regulation, xylose transport, and D-ribose biosynthetic engineering and fermentation process was provided. It would be useful for production of other valuable metabolites from xylose in B. subtilis.