Genomic and metabolic analysis of Komagataeibacter xylinus DSM 2325 producing bacterial cellulose nanofiber

Abstract: Bacterial cellulose nanofiber (CNF) is a polymer with a wide range of potential industrial applications, thanks to its excellent physical properties. Several Komagataeibacter species produce CNF with Komagataeibacter xylinus being a model organism for the CNF production. However, industrial application of CNF has suffered from the low bacterial production capacity. To this end, we present complete genome sequence and a genome-scale metabolic model (GEM) of K. xylinus DSM 2325 in order to facilitate engineering of this bacterium for the enhanced CNF production. Genome analysis of this bacterium revealed that they possessed a set of genes associated with CNF biosynthesis and regulation, which were also conserved among other six Komagataeibacter species having complete genome information. To better understand this bacterium’s metabolic behavior, we also reconstructed a GEM named as kxyGEM using the established protocol and the experimental growth data generated in this study. The complete kxyGEM was used to predict the effects of overexpressing target genes in K. xylinus DSM 2325. This prediction was experimentally validated by introducing the heterologous pgi or gnd gene in K. xylinus DSM 2325, which resulted in a greater CNF titer. Genome sequence data and kxyGEM generated in this study should be useful resources for systems metabolic engineering of K. xylinus DSM 2325 and other relevant strains for the optimal CNF production.