Glycoside hydrolase inventory drives plant polysaccharide deconstruction by the extremely thermophilic bacterium XXXX .

@entity6122 @entity57678 @entity2247 @entity26979 @entity1735 @entity46088 @entity5070 @entity413 @entity13254
The genome of @entity46088 encodes a range of glycoside hydrolases (GHs) that mediate plant biomass deconstruction by this bacterium. Two GH-based genomic loci that appear to be central to the hydrolysis of hemicellulosic and cellulosic substrates were examined. XynB-XynF (Csac_2404-Csac_2411) encodes intracellular and extracellular GHs that are active towards xylan and xylan side-chains, as well as @entity5070 cellulose (CMC). XynD (Csac_2409) and XynE (Csac_2410) were produced recombinantly and confirmed to be xylanases. XynF (Csac_2411) was produced in two separate polypeptides, each with one GH43 catalytic domain displaying a-L-arabinofuranosidase activity. CelA-ManB (Csac_1076-Csac_1080) encodes four multi-domain, extracellular GHs, including CelB (Csac_1078), a 118 kDa extracellular enzyme not present in the other genome-sequenced member of this genus, @entity57678 (formerly @entity57678 ). CelB contains both GH10 and GH5 domains, separated by a family 3 @entity1735 -binding module (CBM3). CelB encoded in Csac_1078 differed from the version originally reported (Saul et al., 1990, Appl Environ Microbiol 56:3117   3124) with respect to linker regions. CelB hydrolyzed xylan and CMC, as well as @entity2247 b-glucan, glucomannan, and @entity26979 . For all substrates tested, intact CelB was significantly more active than either the individual GH5 and GH10 domains or the two discrete domains together, indicating that the multi-domain architecture is essential for complex @entity1735 hydrolysis. Transcriptomes for @entity46088 grown at 70  C on @entity413 , @entity6122 , xyloglucan, @entity13254 , and poplar revealed that certain GHs were particularly responsive to growth on @entity13254 and poplar and that CelB was in the top decile of all transcripts during growth on the plant biomass.
