| IED ID | IndEnz0004000167 |
| Enzyme Type ID | xylanase000167 |
| Protein Name |
Endo-1,4-beta-xylanase B Xylanase B EC 3.2.1.8 1,4-beta-D-xylan xylanohydrolase B |
| Gene Name | xynB |
| Organism | Paenibacillus barcinonensis |
| Taxonomic Lineage | cellular organisms Bacteria Terrabacteria group Firmicutes Bacilli Bacillales Paenibacillaceae Paenibacillus Paenibacillus barcinonensis |
| Enzyme Sequence | MSTEIPSLSASYANSFKIGAAVHTRMLQTEGEFIAKHYNSVTAENQMKFEEVHPREHEYTFEAADEIVDFAVARGIGVRGHTLVWHNQTPAWMFEDASGGTASREMMLSRLKQHIDTVVGRYKDQIYAWDVVNEAIEDKTDLIMRDTKWLRLLGEDYLVQAFNMAHEADPNALLFYNDYNETDPVKREKIYNLVRSLLDQGAPVHGIGMQGHWNIHGPSMDEIRQAIERYASLDVQLHVTELDLSVFRHEDQRTDLTEPTAEMAELQQKRYEDIFGLFREYRSNITSVTFWGVADNYTWLDNFPVRGRKNWPFVFDTELQPKDSFWRIIGQD |
| Enzyme Length | 332 |
| Uniprot Accession Number | O69231 |
| Absorption | |
| Active Site | ACT_SITE 134; /note=Proton donor; /evidence=ECO:0000250; ACT_SITE 241; /note=Nucleophile; /evidence=ECO:0000250 |
| Activity Regulation | ACTIVITY REGULATION: Completely inhibited by Ag(2+), Cu(2+), Hg(2+), Mn(2+), Pb(2+) and Sn(2+). Strongly inhibited by Fe(2+) and Zn(2+). Co(2+) and Ni(2+) cause little inhibition while Ca(2+) and Mg(2+) do not affect enzyme activity, and Ba(2+) produces a small stimulating effect. Irreversibly inactivated by SDS in vitro. {ECO:0000269|PubMed:8998999}. |
| Binding Site | |
| Calcium Binding | |
| catalytic Activity | CATALYTIC ACTIVITY: Reaction=Endohydrolysis of (1->4)-beta-D-xylosidic linkages in xylans.; EC=3.2.1.8; Evidence={ECO:0000269|PubMed:12698280, ECO:0000269|PubMed:8998999}; |
| DNA Binding | |
| EC Number | 3.2.1.8 |
| Enzyme Function | FUNCTION: Plays a role in plant xylan biodegradation, probably via the hydrolysis of short xylooligosaccharides resulting from extracellular xylan hydrolysis, once they have been transported inside cells. Shows similar activity on xylans of different rate of arabinose or methylglucuronic substitution. Also displays high activity on aryl-xylosides. Is active on xylotetraose and xylotriose, but does not hydrolyze xylobiose, indicating that XynB is a xylanase and not a beta-xylosidase. {ECO:0000269|PubMed:12698280, ECO:0000269|PubMed:8998999}. |
| Temperature Dependency | BIOPHYSICOCHEMICAL PROPERTIES: Temperature dependence: Optimum temperature is 50 degrees Celsius. Loses 100% activity after incubation for 15 minutes at 50 degrees Celsius. {ECO:0000269|PubMed:8998999}; |
| PH Dependency | BIOPHYSICOCHEMICAL PROPERTIES: pH dependence: Optimum pH is 5.5. Shows more than 75% of maximum activity from pH 5 to 10. Is still active at pH 12. {ECO:0000269|PubMed:8998999}; |
| Pathway | PATHWAY: Glycan degradation; xylan degradation. |
| nucleotide Binding | |
| Features | Active site (2); Beta strand (14); Chain (1); Domain (1); Helix (13); Initiator methionine (1); Turn (5) |
| Keywords | 3D-structure;Carbohydrate metabolism;Cytoplasm;Direct protein sequencing;Glycosidase;Hydrolase;Polysaccharide degradation;Xylan degradation |
| Interact With | |
| Induction | |
| Subcellular Location | SUBCELLULAR LOCATION: Cytoplasm {ECO:0000269|PubMed:12698280}. Note=Is not secreted to the medium but instead remains cell-associated, in the soluble fraction, even in late stationary-phase cultures. |
| Modified Residue | |
| Post Translational Modification | |
| Signal Peptide | |
| Structure 3D | X-ray crystallography (3) |
| Cross Reference PDB | 3EMC; 3EMQ; 3EMZ; |
| Mapped Pubmed ID | 19940147; |
| Motif | |
| Gene Encoded By | |
| Mass | 38,561 |
| Kinetics | |
| Metal Binding | |
| Rhea ID | |
| Cross Reference Brenda |