The Effect of Magnesium Concentration on Chlorophyll and Catalase Development in Chlorella

Abstract

Syntheses of the metalloporphyrins chlorophyll and catalase in Chlorella vulgaris were correlated with growth effects in the algal cells, which were cultured in nutrient solns. containing glucose and differing in Mg concn. Mg deficiency, which appeared in the 2.8 ppm. Mg and lower Mg cultures, arrested chlorophyll synthesis and had differing effects on catalase activity depending on the concentration of Mg. A transient large rise in catalase activity following the appearance of Mg deficiency symptoms is interpreted to indicate that catalase (or porphyrin) may be synthesized at a concn. of Mg insufficient to maintain chlorophyll synthesis, and that the biosyntheses of these porphyrin compounds are closely related.