Xanthan is by far the commercially most important natural polysaccharide of microbial origin. The high industrial relevance of xanthan can be explained by its extraordinary qualities as rheological control agent in aqueous systems and by its stabilizing properties in suspensions and emulsions. The quantity of xanthan consumed per year was estimated 160,000 tons implemented in a wide range of industrial applications ranging from food, pharmaceutical, and oil drilling industry. The multifunctionality of xanthan gum leads to a predicted market value of USD 452.8 million by 2022.
It is produced by the Gram negative phytopathogen Xanthomonas campestris pv. campestris (Xcc). After the whole genome sequence of Xanthomonas campestris pv. campestris B100 could be revealed, post-genomics approaches were used to elucidate the xanthan biosynthesis.