3s2c

Publication Abstract from PubMed

alpha-L-arabinofuranosidases (EC 3.2.1.55) participate in the degradation of a variety of L-arabinose-containing polysaccharides and interact synergistically with other hemicellulases in the production of oligosaccharides and bioconversion of lignocellulosic biomass into biofuels. In this work, the structure of a novel thermostable family 51 (GH51) alpha-L-arabinofuranosidase from Thermotoga petrophila RKU-1 (TpAraF) was determined at 3.1 A resolution. The TpAraF tertiary structure consists of an (alpha/beta)-barrel catalytic core associated with a C-terminal beta-sandwich domain, which is stabilized by hydrophobic contacts. In contrast to other structurally characterized GH51 AraFs, the accessory domain of TpAraF is intimately linked to the active site by a long beta-hairpin motif, which modifies the catalytic cavity in shape and volume. Sequence and structural analyses indicate that this motif is unique to Thermotoga AraFs. Small angle X-ray scattering investigation showed that TpAraF assembles as a hexamer in solution and is preserved at the optimum catalytic temperature, 65 degrees C, suggesting functional significance. Crystal packing analysis shows that the biological hexamer encompasses a dimer of trimers and the multiple oligomeric interfaces are predominantly fashioned by polar and electrostatic contacts.

Structure of a novel thermostable GH51 alpha-L-arabinofuranosidase from Thermotoga petrophila RKU-1.,Souza TA, Santos CR, Souza AR, Oldiges DP, Ruller R, Prade RA, Squina FM, Murakami MT Protein Sci. 2011 Sep;20(9):1632-7. doi: 10.1002/pro.693. Epub 2011 Aug 3. PMID:21796714^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.