LEAFLET III 

 THE STUDY OF OBLIGATELY ANAEROBIC BACTERIA' 



It is impossible to list here all of the methods which have been 

 proposed for the study of anaerobic bacteria; an attempt is made, 

 however, to outline a number of technics which have been used 

 widely and which should ordinarily be suitable for routine studies 

 of anaerobic species. Those interested in other technics are advised 

 to consult Section B of the subject index bibliography relating to 

 the anaerobic bacteria (McCoy and McClung, 1939; McClung and 

 McCoy, 1941). The worker who has had no experience with anaero- 

 bic bacteria should study some of the articles which deal with prin- 

 ciples of anaerobic culture or which record the results of a study 

 of a considerable number of strains (Committee upon anaerobic 

 bacteria and infections, 1919; Fildes, 1931; Hall, 1922, 1928, 1929; 

 Heller, 1921; Knorr, 1923, 1924; McCoy, et al, 1926, 1930; Mcintosh, 

 1917; Meyer, 1928; Reed and Orr, 1941; Robertson and O'Brien, 

 1929; Soule, 1932; Spray, 1936; Zeissler, 1930; Zeissler and Rassfeld, 

 1928). These are suggested rather than the monographs (Hibler, 

 1908; Weinberg et Seguin, 1918; Weinberg et Ginsbourg, 1927; 

 Weinberg, Nativelle, et Prevot, 1937) which are not distributed 

 widely. 



The organisms which we call obligate anaerobes, are those that 

 require strict exclusion of atmospheric oxygen from the immediate 

 environment in which they are to grow. It is not easy to answer 

 the question of the best method of determining whether or not a 

 given organism is an obligate anaerobe. The catalase reaction, 

 when applied to pure culture, gives presumptive evidence, for obligate 

 anaerobes usually are catalase-negative. For this reaction a plate 

 culture of the organism in question is flooded with a 10% solution 

 of H2O2. The evolution of gas bubbles from the colonies denotes 

 the presence of catalase. 



If the proper material for the catalase reaction is not available. 



'The methods and technics suggested herein are those recommended for use with 

 the more common spore-forming anaerobic species. Many of these methods are suit- 

 able, also, for the study of the non-spore-forming types, and for the present no attempt 

 will be made in this Leaflet to outline particular methods of study for these. If the 

 technics herein outlined do not prove satisfactory, the worker interested in the patho- 

 genic non-spore-formers should consult the re%'iew of Dack (1940) and the publications 

 of Prevot (1924, 1925, 1938, 1940a, 1940b). Non-pathogenic types exist, as for 

 example, the methane organisms discussed by Barker (1936). For the complete 

 literature on all types refer to Section Id (non-spore-formers) in the bibliography of 

 McCoy and McClung (1939) and McClung and McCoy (1941). 



III. ,-3 



