Glucose-6-phosphate dehydrogenase from camel liver was purified to homogeneity by ammonium sulfate precipitation and a combination of DEAE-cellulose, Sephacryl S-300 gel filtration, and 2′, 5′ ADP Sepharose 4B affinity chromatography columns. The specific activity of camel liver G6PD is increased to 1.80438 units/mg proteins with 63-fold purification. It turned out to be homogenous on both native PAGE and 12% SDS PAGE, with a molecular weight of 64 kDa. The molecular weight of the native form of camel liver G6PD was determined to be 194 kDa by gel filtration indicating a trimeric protein. The K m value was found to be 0.081 mM of NADP+. Camel liver G6PD displayed its optimum activity at pH 7.8 with an isoelectric point (pI) of pH 6.6–6.8. The divalent cations MgCl2, MnCl2, and CoCl2 act as activators; on the other hand, CaCl2 and NiCl2 act as moderate inhibitors, while FeCl2, CuCl2, and ZnCl2 are potent inhibitors of camel liver G6PD activity. NADPH inhibited camel liver G6PD competitively with K i value of 0.035 mM. One binding site was deduced for NADPH on the enzyme molecule. This study presents a simple and reproducible purification procedure of G6PD from the camel liver.

Background Honey bee venom contains various enzymes with wide medical and pharmaceutical applications. Results The phospholipase A2 (PLA2) has been apparently purified from the venom of Egyptian honey bee (Apis mellifera lamarckii) 8.9-fold to a very high specific activity of 6033 U/mg protein using DEAE–cellulose and Sephacryl S-300 columns. The purified bee venom PLA2 is monomeric 16 kDa protein and has isoelectric point (pI) of 5.9. The optimal activity of bee venom PLA2 was attained at pH 8 and 45 °C. Cu2+, Ni2+, Fe2+, Ca2+, and Co2+ exhibited a complete activating effect on it, while Zn2+, Mn2+, NaN3, PMSF, N-Methylmaleimide, and EDTA have inhibitory effect. Conclusions The purified bee venom PLA2 exhibited anti-platelet aggregation and anti-coagulation activities which makes it promising agent for developing novel anti-clot formation drugs in future.

Glucose-6-phosphate dehydrogenase (G6PD) is a key regulatory enzyme involved in the pentose phosphate pathway. This works represents purification of two buffalo liver glucose-6-phosphate dehydrogenases (BLG6PD1 and BLG6PD2) using combination of ammonium sulfate precipitation and several chromatographic columns. Both enzymes (BLG6PD1 and BLG6PD2) were homogenous on both native PAGE as well as 12% SDS PAGE with molecular weights of 28 and 66 kDa. The molecular weight of BLG6PD1 and BLG6PD2 native forms were determined to be 28 and 66 kDa by gel filtration; indicating monomeric proteins. The K(m) values for BLG6PD1 and BLG6PD2 estimated to be 0.059 and 0.06 mM of β-nicotinamide adenine dinucleotide phosphate. The optimum activity of BLG6PD1 and BLG6PD2 were displayed at pH 8.0 and 8.2 with an isoelectric point (pI) of pH 7.7-7.9 and 5.7-5.9. The divalent cations MgCl2, and CoCl2 act as activators, on the other hand, FeCl2, CuCl2 and ZnCl2 are potent inhibitors of BLG6PD1 and BLG6PD2 activity. NADPH inhibited both isoenzymes competitively with Ki values of 0.012 and 0.030 mM. This study describes a reproducible purification scheme of G6PD from the liver of buffalo as a rich source.

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Background Superoxide dismutase is an important antioxidative stress enzyme which is found in honeybee venom and has a wide pharmaceutical and medical applications. Results We reported the purification and characterization of venom SOD from Egyptian honeybee Apis mellifera lamarckii and termed BVSOD. It was purified to homogeneity from the Egyptian honeybee venom. The purification procedures included crude extraction, DEAE-cellulose anion exchange column chromatography, and Sephacryl S-300 gel filtration column chromatography. The purified BVSOD is found to be homogeneous as investigated by native PAGE. It exhibited homodimeric structure with a molecular weight of native form of 32 kDa and subunits of 16.0 kDa. It displayed the maximum activity at pH 7.4. CuCl2, ZnCl2, and MgCl2 and elevated the activity of BVSOD, while CoCl2, FeCl2, and NiCl2 inhibited BVSOD activity. Potassium cyanide and hydrogen peroxide were most potent inhibitors for BVSOD activity suggesting that it is a Cu/Zn-SOD type. Conclusions The purified BVSOD is found to have antimicrobial and antitumor activities which can be used for various medical and clinical applications.