Production of acidic xylooligosaccharides from methylglucuronoarabinoxylans by Bacillus subtilis strain MR44

摘要

BACKGROUNDBacillus subtilis 168 secretes endoxylanases Xyn11A and Xyn30C and arabinofuranohydrolase Axh43 that process xylans in hemicellulose fractions. Engineered strain MR44 with a deletion in the xynA gene encoding Xyn11A, converts hardwood methylglucuronoxylans (MeGX(n)) of dicots to defined acidic xylooligosaccharides (U-XOS) with a single methylglucuronate linked to xylooligosaccharides with an average ratio of one methylglucuronate to 6-7 xyloses as value-added products. The MR44 strain also secretes Axh43 that catalyses release of arabinose from methylglucuronoarabinoxylans (MeGAX(n)) of monocots.