INTRODUCTION 



excreted ^-aminobenzoic acid ; {d) one hour after ingestion of p-a.mmo- 

 benzoic acid and sulphathiazole, the blood was not bacteriostatic to 

 Pneumococcus, just as if _/)-aminobenzoic acid had been added in vitro ; 

 and {e) although effective in preventing bacteriostasis, ^-aminobenzoic 

 acid did not prevent sulphonamide fever and rash whether given 

 subsequently or simultaneously. 



Further support to the theory of Woods and Fildes was given by 

 S. D. Rubbo and J. M. Gillespie/^ who found that Clostridium aceto- 

 butylicum required ;^-aminobenzoic acid for growth, and that the 

 amount of sulphanilamide required to inhibit growth was dependent 

 on the amoimt of _/)-aminobenzoic acid present. One part by weight 

 of ^-aminobenzoic acid antagonised 26,000 parts of sulphanilamide. 



The discovery of the antagonistic effect of sulphanilamide and 

 ;/)-aminobenzoic acid led to the discovery of other pairs of chemically 

 related substances, one a growth stimulant and the other a growth 

 inhibitor. S. D. Rubbo and J. M. Gillespie,^ ^ for example, reported 

 that ^-aminophenylacetic acid was a growth factor for Clostridium 

 acetohutylicum and that ;/)-aminophenylmethane sulphonic acid acted 

 as a growth inhibitor for this organism. Other examples have already 

 been discussed (pages 126, 292, 345, 397). 



References to Section i 



1. F. Mietzsch and J. Klarer, D.R.P. 607537. 



2. G. Domagk, Deut. med. Woch., 1935, 61, 250, 928. 



3. J. Tr6fouel, Mme. J. Tr6fouel, F. Nitti and D. Bo vet, Compt. rend. 



Soc. Biol., 1935, 120, 756. 



4. P. Gelmo, /. prakt. Chem., 1906 (2), 77, 369. 



5. L. Colebrook, G. A. H. Buttle and R. A. Q. O'Meara, Lancet, 



1936, 2, 1323. 



6. A. T. Fuller, ibid., 1937, 1» i94- 



7. J. S. Lockwood, /. Immunology, 1938, 35, 155 ; J. S. Lockwood 



and H. M. Lynch, /. Amer. Med. Assoc, 1940, 114, 935. 



8. T. C. Stamp, Lancet, 1939, 2, 10. 



9. H. N. Green, Brit. J. Exp. Path., 1940, 21, 38. 



10. R. West and A. F. Coburn, /. Exp. Med., 1940, 72, 91. 



11. CM. MacLeod, ihid., 217. 



12. D. D. Woods, Brit. J. Exp. Path., 1940, 21, 74. 



13. F. R. Selbie, ihid., 90. 



14. P. Fildes, Lancet, 1940, 1, 956. 



15. S. D. Rubbo and J. M. Gillespie, Nature, 1940, 146, 838. 



16. E. Strauss, J. H. Dingle and M. Finland, Proc. Soc. Exp. Biol. 



Med., 1941, 46, 131, 133 ; W. W. Spink and J. Jermsta, ibid., 

 1941. 47, 395- 



17. E. Strauss, F. C. Lowell and M. Finland, /. Clin. Invest., 1941, 20, 



189. 



18. S. D. Rubbo and J. M. Gillespie, Lancet, 1942, 1, 36. 



547 



