02436naa a2200349 a 450000100080000000500110000800800410001902400560006010000190011624501790013526000090031430000080032349000080033152013790033965000210171865000170173965000120175665000110176865000080177965300240178770000200181170000170183170000200184870000190186870000150188770000190190270000160192170000190193770000170195670000180197377300950199121263342020-11-06       2020    bl uuuu     u00u1 u    #d7 ahttps://doi.org/10.1016/j.ijbiomac.2020.09.2362DOI1 aLIMA, R. A. T.  aFunctional and structural characterization of a novel GH3 Beta-glucosidase from the gut metagenome of the Brazilian Cerrado termite Syntermes wheeleri.h[electronic resource]  c2020  a165  v165  aIn this study, a GH3 family Beta-glucosidase (Bgl7226) from metagenomic sequences of the Syntermes wheeleri gut, a Brazilian Cerrado termite, was expressed, purified and characterized. The enzyme showed two optimum pHs (pH 7 and pH 10), and a maximum optimum temperature of about 40 °C using 4-Nitrophenyl ?-D-glucopyranoside (pNPG) as substrate. Bgl7226 showed higher enzymatic activity at basic pH, but higher affinity (Km) at neutral pH. However, at neutral pH the Bgl7226 enzyme showed higher catalytic efficiency (kcat/Km) for pNPG substrate. Predictive analysis about the enzyme structure-function relationship by sequence alignment suggested the presence of multi-domains and conserved catalytic sites. Circular dichroism results showed that the secondary structure composition of the enzyme is pH-dependent. Small conformational changes occurred close to the optimum temperature of 40 o C, and seem important for the highest activity of Bgl7226 observed at pH 7 and 10. In addition, the small transition in the unfolding curves close to 40 o C is typical of intermediates associated with proteins structured in several domains. Bgl7226 has significant Beta-glucosidase activity which could be attractive for biotechnological applications, such as plant roots detoxification; specifically, our group is interested in cassava roots (Manihot esculenta) detoxification.  aBeta-glucosidase  aMetagenomics  aCerrado  aEnzima  aRNA  aGenômica ambiental1 aOLIVEIRA, G. d.1 aSOUZA, A. A.1 aLOPES, F. A. C.1 aSANTANA, R. H.1 aISTVAN, P.1 aQUIRINO, B. F.1 aBARBOSA, J.1 aFREITAS, S. d.1 aGARAY, A. V.1 aKRUGER, R. H.  tInternational Journal of Biological Macromoleculesgv. 165, Part A, p. 822-834, Dec. 2020.