| IED ID | IndEnz0008000166 |
| Enzyme Type ID | cellulase000166 |
| Protein Name |
Reducing-end xylose-releasing exo-oligoxylanase Rex8A Rex EC 3.2.1.156 |
| Gene Name | rex8A DFQ00_11062 |
| Organism | Paenibacillus barcinonensis |
| Taxonomic Lineage | cellular organisms Bacteria Terrabacteria group Firmicutes Bacilli Bacillales Paenibacillaceae Paenibacillus Paenibacillus barcinonensis |
| Enzyme Sequence | MNITGKGAYDTGTYANLFQRSGYREDEIKARLEQTWNDLFYGDEHTRIYYPVGDDKGYMLDTGNDDVRSEGMSYGMMMAVQMDKKHEFDRLWNYAYTYMQHTEGRYKDYFAWHCKPDGTRLSPGPAPDGEEFFAMALFFASNRWGDGPAPYDYQAQARKILHACLHQGEQGEGDPMWEPSNRLIKFIPELPFSDPSYHLPHFYELFAQYANEQDRTFWKEAAEASRAYLRTACHPVTGLSPEYANYDGTPAPVQLHGDFRHFYSDAYRVAANVALDWEWFRKDPWQVQQSNRIQAFFSDIDVSDYRRYTIEGEPFNEPALHPVGLLATNAMASLAADGPDADSFVKRFWNTPLRQGKRRYYDNCLYFFTMLALSGNYRVY |
| Enzyme Length | 380 |
| Uniprot Accession Number | A0A0S2UQQ5 |
| Absorption | |
| Active Site | ACT_SITE 70; /note=Proton donor; /evidence=ECO:0000305|PubMed:27316951; ACT_SITE 265; /note=Proton acceptor; /evidence=ECO:0000305|PubMed:27316951 |
| Activity Regulation | |
| Binding Site | |
| Calcium Binding | |
| catalytic Activity | CATALYTIC ACTIVITY: Reaction=Hydrolysis of (1->4)-beta-D-xylose residues from the reducing end of oligosaccharides.; EC=3.2.1.156; Evidence={ECO:0000269|PubMed:27316951}; |
| DNA Binding | |
| EC Number | 3.2.1.156 |
| Enzyme Function | FUNCTION: Involved in depolymerization of xylan, a major component of the lignocellulosic substrates. Acts as an exo-oligoxylanase that efficiently hydrolyzes xylooligosaccharides, releasing xylose from their reducing ends. Hydrolyzes xylooligomers of 3 to 6 xylose units to xylose and xylobiose. Besides linear xylooligosaccharides, also hydrolyzes branched xylooligomers, such as xylooligomers decorated with 4-O-methyl-D-glucuronic acid moieties. Its proposed role is the degradation of xylooligomers produced by the activity of extracellular xylanases once they have been transported inside cells. Shows minor activity on polymeric xylan (glucuronoxylan from beechwood). Is not active on cellooligosaccharides or cellulosic substrates, or on other polysaccharides such as pectin, polygalacturonic acid, laminarin, or lichenan. {ECO:0000269|PubMed:27316951}. |
| Temperature Dependency | BIOPHYSICOCHEMICAL PROPERTIES: Temperature dependence: Optimum temperature is 40 degrees Celsius for the hydrolysis of xylotriose. {ECO:0000269|PubMed:27316951}; |
| PH Dependency | BIOPHYSICOCHEMICAL PROPERTIES: pH dependence: Optimum pH is 7 for the hydrolysis of xylotriose. {ECO:0000269|PubMed:27316951}; |
| Pathway | PATHWAY: Glycan degradation; xylan degradation. {ECO:0000269|PubMed:27316951}. |
| nucleotide Binding | |
| Features | Active site (2); Beta strand (14); Chain (1); Helix (19); Mutagenesis (1); Turn (6) |
| Keywords | 3D-structure;Carbohydrate metabolism;Glycosidase;Hydrolase;Polysaccharide degradation;Xylan degradation |
| Interact With | |
| Induction | |
| Subcellular Location | |
| Modified Residue | |
| Post Translational Modification | |
| Signal Peptide | |
| Structure 3D | X-ray crystallography (7) |
| Cross Reference PDB | 6SHY; 6SRD; 6SUD; 6TO0; 6TOW; 6TPP; 6TRH; |
| Mapped Pubmed ID | 32352213; |
| Motif | |
| Gene Encoded By | |
| Mass | 44,217 |
| Kinetics | BIOPHYSICOCHEMICAL PROPERTIES: Kinetic parameters: KM=1.64 mM for xylotriose {ECO:0000269|PubMed:27316951}; Vmax=152.2 umol/min/mg enzyme for the hydrolysis of xylotriose {ECO:0000269|PubMed:27316951}; Note=kcat is 118.8 sec(-1) for the hydrolysis of xylotriose. {ECO:0000269|PubMed:27316951}; |
| Metal Binding | |
| Rhea ID | |
| Cross Reference Brenda | 3.2.1.156; |