The fine structure of gamma phage of Bacillus anthracis was studied by electron microscopy with a negative-staining technique. The phage has a hexagonal head and a long tail without a sheath. By electrophoresis on polyacrylamide gels, the proteins of the phage particles are separate into 10 polypeptides with molecular weights ranging from 140 000 to 12 000.

In T lymphocytes stimulated by concanavalin A (Con A), interleukin 2 (IL-2) acts on the late G1 stage of the cell cycle. Ca2+ uptake by T cells was not enhanced with the stimulation of Con A (initiation) or IL-2 (late G1 stage), but Ca2+ requirement was observed at the two stages. These results indicate that the enhancement of Ca2+ uptake is not necessary, but intracellular Ca2+ may act as an important messenger in T cell mitogenesis.

Results of experiments have indicated that reduction in biological activities at high concentrations of Japanese encephalitis virus is caused by aggregates of the virus by concanavalin A. The possibility exists that the concanavalin A binding site is different from hemagglutination and antireceptor sites of Japanese encephalitis virus.

A purified toga-alphavirus, Getah (GE T), showed optimal hemolytic activity for one-day-old chick red blood cells when incubated at 37 C for 120 min at pH 6.2. Experimental data obtained from various angles, such as pH dependency, inhibition by virus-specific antiserum and by concanavalin A, indicated that the hemolysis was a property of the virus particle itself. Although the mechanism of hemolysis by togaviruses has not been known, our results indicated that viral lipids may participate in this activity since the hemolytic activity was impaired by delipidation procedures.

Cell wall preparations of Bacillus anthracis, strain Pasteur No. 2‐H, were treated with heat or with acetone and ether. Both of the treated cell walls preparations inactivated γ phage. The centrifuged supernatant of the heat‐treated cell walls was fractionated on Sephadex G‐200, and four fractions containing reducing sugars were obtained. The first fraction had the phage‐inactivating activity. On the other hand, the fourth fraction had no phage‐inactivating activity, but strongly inhibited phage adsorption to the cell walls. In the fourth fraction, glutamic acid, alanine, 2, 6‐diaminopimelic acid and glucosamine were detected by paper chromatography after acid hydrolysis. Authentic D,L‐2, 6‐diaminopimelic acid and D‐glucosamine markedly inhibited phage adsorption to the cell walls. D‐Galactosamine, D‐mannosamine and L‐lysine also showed similar activities. Results suggest the possibility that one or a combination of these substances defines the characteristics of phage adsorption to the cell walls of B. anthracis, strain Pasteur No. 2‐H.