THE PRODUCTION OF HYDROGEN SULPHIDE BY 



BACTERIA 



JOHN T. MYERS 



From the Department of Hygiene and Bacteriology , the University of Chicago 



Received for publication, December 11, 1919 



Hydrogen sulphide formation in sewage is supposed to be due to 

 two distinct processes, the splitting of protein by certain organ- 

 isms and the reduction of inorganic sulphates by others. Led- 

 erer (1913) concludes that more hydrogen sulphide is formed 

 under anaerobic than under aerobic conditions. He thinks 

 that the formation of hydrogen sulphide from protein is a selective 

 process and that it depends a great deal on the position of the 

 sulphur radical in the protein molecule. At any rate other fac- 

 tors than reduction are involved in hydrogen sulphide formation. 

 An organism may be a very strong nitrate reducer and at the 

 same time a weak hydrogen sulphide former, although both reac- 

 tions are reducing processes. Lederer is of the opinion that the 

 reduction of inorganic sulphates may however be an important 

 factor in hydrogen sulphide formation, and thinks it probable 

 that the action may be due to some unknown specific organism 

 similar to the Spirillum desulphuricans of Beijerinck (1895). 



Several workers have observed the formation of hydrogen sul- 

 phide in large quantities in the effluent of sewage disposal plants. 

 Barr and Buchanan (1912) report the isolation of a specific or- 

 ganism in one such instance. Clark (1913) and others have re- 

 ported the reduction of inorganic sulphates in sewages. 



Sulphur metabolism may also play a beneficial role in sewage 

 disposal in that certain species of bacteria may cause the oxida- 

 tion of sulphur and of hydrogen sulphide to sulphates thus reduc- 

 ing the amount of odor. This is a well known property of such 

 organisms as Beggiatoa and Thiothrix (Jordan, 1918). 



231 



