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A fourto sixfold increase in specific activity of dihydrodipicolinic acid synthase was observed during sporulation of Bacillus cereus. The enzyme from cells harvested before and after the increase in specific activity appeared to be very similar as judged by pH optima, heat denaturation kinetics, apparent Michaelis constants, chromatography on diethylaminoethyl-cellulose and Sephadex G-200, and polyacrylamide gel electrophoresis. Studies with various combinations of amino acids and one of the enzyme substrates, pyruvate, failed to give evidence for control of the enzyme by activation, inhibition, repression, induction, or stabilization. Omission of calcium from the sporulation medium had no significant effect on the specific activity pattern of the enzyme as a function of age of culture. Dipicolinic acid and diaminopimelic acid are two substances that apparently play key roles in the bacterial sporulation process. Both compounds are formed as a result of the functioning of the lysine biosynthetic pathway. Forman and Aronson (8) have shown that, in Bacillus cereus, aspartokinase (EC 2.7.24), aspartic ,-semialdehyde dehydrogenase (EC 1.2.1.10), dihydrodipicolinic acid (DHDPA) synthase (pyruvate aspartic semialdehyde-condensing en

Dextran-methylprednisolone conjugate can effectively deliver the corticosteroid to its site of action for immunosuppression, resulting in more intense and sustained effects when compared with the free drug administration.