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Abstract : |
Some environmental factors affecting phosphatase activity of the cyanobacterium Lyngbya majuscula found on the coral reefs in the Red Sea were investigated. Phosphatase activity of L. majuscula was restricted only to phosphomonoesterase (PMEase) without any detectable level of phosphodiesterase (PDEase) during all experiments. The maximum enzyme activity was obtained at 35°C (69.1 pNP μmol mg-1 dry wt. h-1) and at pH 10 (89.1 mol pNP mg-1 dry wt. h-1). The activity was markedly inhibited by Fe, Zn, Na, K and P ions at high concentrations (1 and 10 mM), but lower concentrations (0.01 and 0.1 mM) enhanced this activity. The highest concentration of Ca and Mg ions (10 mM) inhibited the enzyme activity, while lower concentrations stimulated this activity. Salinity had a marked effect on the enzyme activity, with a maximum obtained at 5‰. , Some environmental factors affecting phosphatase activity of the cyanobacterium Lyngbya majuscula found on the coral reefs in the Red Sea were investigated. Phosphatase activity of L. majuscula was restricted only to phosphomonoesterase (PMEase) without any detectable level of phosphodiesterase (PDEase) during all experiments. The maximum enzyme activity was obtained at 35أƒâ€ڑأ‚آ°C (69.1 pNP أƒإ½أ‚آ¼mol mg-1 dry wt. h-1) and at pH 10 (89.1 mol pNP mg-1 dry wt. h-1). The activity was markedly inhibited by Fe, Zn, Na, K and P ions at high concentrations (1 and 10 mM), but lower concentrations (0.01 and 0.1 mM) enhanced this activity. The highest concentration of Ca and Mg ions (10 mM) inhibited the enzyme activity, while lower concentrations stimulated this activity. Salinity had a marked effect on the enzyme activity, with a maximum obtained at 5أƒآ¢أ‚€أ‚آ°., |
