Cellulase enzyme was purified and characterized from termite soldiers (Ametermes eveuncifer) using 70% ammonium sulphate precipitation, ion exchange chromatography and affinity chromatography. The enzyme isolated had a specific activity of 5.04 U/mg with a percentage yield of 11.7%. The enzyme showed maximum activity at 50 0 C and pH 8. The enzyme was not inhibited by Ba 2+ at a concentration of 1mM and Pb 2+ at 10 mM concentration but was inhibited by other metal ions at 1 mM and 10 mM concentrations of their salts (NaCl, KCl, MnCl 2 , and NiCl 2 ) ,

This study was aimed at investigating the in vivo antimalarial activity (using some biochemical indices) of crude aqueous extracts of the fruiting bodies of Ganoderma lucidum, a mushroom with well-established medicinal properties. A rodent malaria parasite, Plasmodium berghei (1 × 107), was inoculated intraperitoneally into Swiss albino mice. The test groups were administered G. lucidum extract and chloroquine (CQ, as standard drug), while the control groups were administered the same amount of distilled water by an intragastric tube once daily. The antimalarial activity of the extract was investigated from the suppressive, curative, and prophylactic effects of the extract on parasite growth. Serum aminotransferases (AST and ALT), alkaline phosphatase (ALP), and gamma glutamine transpeptidase (γ-GT) levels monitored following the 4-day suppressive test were significantly reduced, with a corresponding significant increase in the livers of mice treated with the extract compared with infected untreated mice. The results obtained from this study provide scientific justification in an animal model of malaria that an ethanolic extract of G. lucidum possesses potent antimalarial activity and also could help ameliorate the attendant Plasmodium-induced liver damage due to malarial infection.

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The shikimate pathway, which produces aromatic amino acids and key intermediates, is critical to the viability of the tuberculosis-causing pathogen Mycobacterium tuberculosis. The enzyme 3-deoxy-D-arabino-heptulosonate 7-phosphate synthase (DAHPS) catalyzes the first committed step of this pathway and possesses regulatory functions. Its active site contains two cysteinyls: one (Cys 87 ) bound to a metal ion, while the other (Cys 440 ) is in proximity to the first but is located on a connecting loop. This arrangement seemingly appeared as a disulfide linkage. However, Cys 440 is not metal binding, and its positioning indicates that it could collapse the disulfide linkage. Hence, its potential role may be more than simply structural support of the active site fold. Using a multiscale computational approach, molecular dynamics (MD) simulations, and DFT-based calculations, the influence of Cys 440 on the active site properties has been investigated. MD simulations reveal an unusually long disulfide bond, more than 3.0 Å, whereas DFT calculations identified two stable active site conformers in the triplet and quintet spin states. Analysis of group spin density distribution identified antiferromagnetic coupling in each conformer, which suggests their relatively low potential energy and stable conformations. The conformer in the triplet spin state could favor enzyme reactivity due to its low HOMO−LUMO energy gap. In addition, reduction of the Cys 440 thiolate group results in collapse of the active site metal−ligand configuration with large exothermicity. Hence, Cys 440 could activate and inactivate the enzyme. For the first time, the study revealed the role of Cys 440 as being vital for the catalytic activity of the enzyme rather than solely for the structural stabilization of its active site. Thus, the findings may lead to a novel basis for antituberculosis drug design and development that would disrupt the contributions of the Cys 440 .

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