THE FOLIC ACID COMPLEX 



increase in the activity of a concentrate of the fermentation L. casei 

 factor towards 5. faecalis R on incubation with vitamin Be conjugase. 



Vitamin Be conjugase is also produced, often in considerable 

 amounts, by many micro-organisms,® but it does not appear to be 

 present in moulds or yeasts and only in small amounts in potatoes.* 

 The enzyme was shown to be different from kidney nucleosidase, the 

 acid phosphatase of almond or potato, the alkaline phosphatase of the 

 small intestine and the j3-glucosidase of almond. 



The activity of the enzyme was inhibited by nucleic acid and 

 sulphydryl-combining reagents.® 



The purification of vitamin Be conjugase was described by Laskowski 

 et al.^^ The process involved treatment with calcium phosphate gel, 

 precipitation with alcohol and repeated concentration of the solution 

 and salting-out with sodium sulphate. A method of estimating the 

 enzyme in animal tissues was worked out, and this was used to ascer- 

 tain its distribution. The enzyme was found to be widely distributed 

 in the rat's body ; the pancreas, brain, intestinal mucosa and bone 

 showed much higher values than the liver. Chicken pancreas, intes- 

 tinal mucosa and liver were very good sources. A similar distribution 

 of the enzyme was observed by Bird et al.^^ They noted that the 

 optimal pH for activity was generally 4-5, but that enzyme prepara- 

 tions from chick and tiukey pancreas were most effective at pH. 7-0 to 

 7-5. Yeast extract contained a potent inhibitor of the enzyme. The 

 vitamin Be contents of several preparations of vitamin Be conjugate 

 were estimated microbiologically after digestion with vitamin Bo 

 conjugase. 



References to Section 6 



1. B. L. O'Dell and A. G. Hogan, /. Biol. Chem., 1943, 149, 323. 



2. E. P. Daniel and O. L. Kline, ibid., 1947, 170, 739. 



3. E. L. R. Stokstad, D. Fordham and A. de Grunigen, ibid., 1947, 



167, 877. 

 3a. O. H. Lowry, O. A. Bessey and E. J. Crawford, ibid., 1949, 180, 



389. 



4. O. D. Bird, S. B. Binkley, E. S. Bloom, A. D. Emmett and J. J. 



Pfiffner, ibid., 1945, 157, 413. 



5. V. Mims and M. Laskowski, ibid., 1945, 160, 493. 



6. P. R. Burkholder, I. McVeigh and K. Wilson, Arch. Biochem,, 



1945, 7, 287. 



7. L. J. Daniel, M. L. Scott, L. C. Norris and G. F. Heuser, /. Biol. 



Chem., 1945, 160, 265. 



8. P. L. Day, V. Mims and J. R. Totter, ibid., 1945, 161, 45. 



9. V. Mims, M. E. Swendseid and O. D. Bird, ibid., 1947, 170, 367. 

 ID. M. Laskowski, V. Mims and P. L. Day, ibid., 1945, 157, 731. 



II. O. D. Bird, M. Robbins, J. M. Vandenbelt and J. J. Pfiffner, ibid., 



1946, 163, 649. 



480 



