Influence on Bio-synthesis of Bovine Serum Gamma Globulin of the Antibody-Promoting Substance “Inosine” (Part 2)

In the previous report, it was made clear that inosine, the antibody-promoting factor, accelerated the biosynthesis of bovine serum gamma globulin (BSG) when applied to the quantitative precipitation test. In the present investigation, 13 substances were selected from among those related to inosine metabolic degradation, and examined in vitro to clarify the interrelations between their action and inosine in the biosynthesis of BSG. I. Of these substances tested, cysteine increased the formation of BSG, whereas its derivatives, such as thiazolidon-4-carboxylate, cysteine-s-sulfonate, and taurin, were ineffective or inhibitory. When cysteine was used together with adenosine, it displayed a potential effect on the biosynthesis of BSG. Moreover, it displayed an additional effect when used together with either inosine or ADP. 2. XMP, CMP, uracil and orotic acid did not act effectively upon the biosynthesis of BSG. 3. SH-inhibiting substances, such as thiourea, potassium iodate, atoxyl, p-aminobenzoic acid, p-chlorobenzoic acid, and cobaltous ion, had an ineffective or inhibitory action upon the biosynthesis of BSG. UMP alone displayed such an accelerating effect as that of cysteine. 4. Pyridoxal, biotin and pantothenic acid had hardly any effect upon the biosynthesis of BSG. 5. When used alone, adrenalin exerted an inhibitory action on the biosynthesis of BSG and a stimulating effect upon the adenosine action.