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Streptomyces sp. B-PNG23 was selected as a promising cellulolytic strain and tested for its ability to produce cellulases from agroindustrial residues. A pH value of 7 and temperature of 28°C were found to be optimal for maximum enzyme production. The highest endoglucanase activity was obtained in a medium comprised of wheat bran (2 g/l), yeast extract (2 g/l), NaCl (2 g/l), NH4Cl (2.5 g/l), and (0.4 g/l) of MgSO4. The enzyme was active at a broad range of pH (5-8) and temperatures (40-70°C). The optimum pH and temperature were 6 and 50°C, respectively. In the presence of metal ions Mn2+, Cu2+ and NH4 + the activity of the enzyme increased significantly. The enzyme retained 50% of its activity after heating at 50°C for 6 h. This enzyme could be considered as a thermotolerant biocatalyst that could be utilized in biotechnological applications

Jonesia denitrificans BN-13 produces six xylanases: Xyl1, Xyl2, Xyl3, Xyl4, Xyl5, and Xyl6; the Xyl4 was purified and characterized after two consecutive purification steps using ultrafiltration and anion exchange chromatography. The xylanase-specific activity was found to be 77 unit (U)/mg. The molecular weight of the Xyl4 estimated using sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) revealed a monomeric isoenzyme of about 42 kDa. It showed an optimum pH value of 7.0 and a temperature of 50 °C. It was stable at 50 °C for 9.34 h. The enzyme showed to be activated by Mn(+2), β-mercaptoethanol, and dithiothreitol (DTT) with a high affinity towards birchwood xylan (with a K(m) of 1 mg ml(-1)) and hydrolysis of oat-spelt xylan with a K(m) of 1.85 mg ml(-1). The ability of binding to cellulose and/or xylan was also investigated.

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Streptomyces sp. strain BPNG23 produces five endoglucanases: endo1, endo 2, endo 3, endo 4 and endo 5.The endo2 has been purified and characterized by two subsequent purification steps with ultrafiltration and anion exchange chromatography. The specific activity of the endoglucanase has been found to be 380.65 U/mg. The molecular weight to the endoglucanase 2 has been estimated with sodium dodecyl sulfate-polyacrylamide gel electrophoresis, revealing that this isoenzyme is a 66 KDa monomeric enzyme. It showed an optimum temperature and pH values respectively of 6.0 and 50 °C. It was thermostable, it exhibited a half-life time 6 h with a temperature of  50 °C, the enzyme was activated by several metal ions Mn+2, NH4+, Zn2+, Ca2+, Fe2+, Ni2+ and  Co2+. It presents a higher affinity towards carboxymethyl cellulose (CMC) with a Km of 6.37 mg/mL and Vmax of 0.056 μmol/mn. This the first of a study of purification and characterization of an endoglucanase produced by a newly isolated actinobacteria strain in Kabylia region (Algeria).

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