Experimental evidence of a xylose--catabolic pathway on the pAO1 megaplasmid of Arthrobacter nicotinovorans

Besides the well-characterized pathway for nicotine degradation (Brandsch, 2006), pAO1 carries a gene cluster of a hypothetical pathway for carbohydrate utilization (figure 1). This cluster consists of ORFs of a transcriptional regulator, of a sugar ABCtransporter and of several putative dehydrogenases and oxidoreductases. Previously, we established that the pAO1 orf39 gene encodes an aldehyde-dehydrogenase (Mihasan et al., 2008) and orf40 encodes an sugar dehydrogenase. The current work is focused on experimental identification of the catabolic pathway substrate of this latter pathway.