An arginase isolated from a capsulated Bacillus anthracis strain was highly purified and crystallized. The chemical and immunological characteristics of this enzyme re described. Some very important properties differ from those of another bacterial arginase, i.e. Staphylococcus aureus arginase, described in a previous paper (Soru et al. (2)). The two arginases have different crystallization forms, different molecular weight, Km, thermostability, Arrhenius activation energy. They have another N-terminal group and are immunologically strictly specific. These differences point to distinct proteins. The fact that two arginases of different origin are structurally non-identical suggests that they may be involved in different metabolic processes. Staphylococcal arginase was shown to participate in a complete ureogenetic cycle, for it also possesses the other enzymes of the cycle (Soru et al. (2)). Except arginase, no other enzyme of this cycle was identified in the capsulated B. anthracis strain. Arginase may be involved in another metabolic pathway, one that is important for the strain, such as the synthesis of glutamic acid, since the capsular material of the strain is a polymer gamma-linked polyglutamic acid, mainly configuration D (Ivanovic and Bruckner (20)). The fact that the N-terminal residue of B. anthracis arginase is a tetramer containing glutamic acid together with proline (in addition to alanine and glycine) suggests that arginase may participate as a regulatory enzyme in the synthesis of glutamic acid from proline via ornithine and arginine, respectively. This pathway is found in many bacteria. The proline oxidase system, which is supposed to catalyse the conversion of proline to glutamic acid, is under study now in Bacillus anthracis strains.

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L-Asparaginase isolated from the BCG strain of Mycobacterium bovis has been purified approximately 100-fold by negative adsorption on Ca-phosphate gel, batchwise adsorption and column chromatography on DEAE-Sephadex, gel filtration through Bio Gel P-200, and crystallization.The final enzyme preparation appeared to be pure on the basis of cellulose acetate and polyacrylamide gel electrophoresis, immunodiffusion, and immunoelectrophoresis in agar gel.Inhibition by crystalline BCG L-asparaginase of blast cell transformation was demonstrated by means of thymidine-3H incorporation in phytohemagglutinin-stimulated rabbit spleen cell cultures. This effect was not observed with heat-inactivated enzyme.Antibody synthesis in spleen cell cultures which were secondarily stimulated in vitro with polio virus was also depressed.Intradermal inoculation of crystalline BCG L-asparaginase in BCG-sensitized guinea pigs gave no significant tuberculin type reaction.

A procedure for the purification of an ornithine carbamoylphosphate transferase isolated from a Staphylococcus aureus strain is reported. The procedure consists of the following steps: water extraction of the crude enzyme by autolysis under a toluene layer of the acetone dried bacteria cells, lyophilization of the crude extract, molecular sieving chromatography on a Bio Gel P‐150 column and as a final step the electrophoresis on Sephadex G‐200 plates. A 100‐fold purification with a 50% yield is realized. The purified preparation so obtained appeared to be pure on the basis of acrylamide gel electrophoresis, thin layer chromatography, immunodiffusion and immunoelectrophoresis. The apparent molecular weight of the enzyme as determined by molecular sieve chromatography is 200 000 ± 30 000. The Km value for l‐ornithine as substrate is 3 mM and for carbamoylphosphate 0.7 mM. Arrhenius activation energy is 13 775 cal/mol. NH2‐terminal amino acid is glycine: COOH‐terminal amino acid is glutamic acid. Two unmasked SH‐groups and two S‐S interchain bridges per molecule were found.

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