title: Inhibition of acetate and propionate formation upon aeration of resting cells of the anaerobic Propionibacterium shermanii: evidence of the Pasteur reaction.
abstract: When resting cell suspensions of the anaerobic P. shermanii were brought to an oxygen concentration of 0.64 mumoles/ml, acid formation was completely inhibited. The cells started to respire on the propionic acid previously accumulated furing anaerobiosis. Glucose consumption was concomitantly decreased to about 60 percent of the rate during anaerobiosis. As the viability of the cells was not affected by the transition to aerobic conditions, the changes observed upon aeration were ascribed to the regulatory properties of the Pasteur reaction. Damage inflicted by oxygen was encountered in the rapid inactivation of propionate respiration. This damage outlived the time of oxygenation, and was manifested during the subsequent anaerobiosis in the decreased activity to form propionate. This indicates that oxygen may inactivate one (or more) enzyme(s) involved in the metabolism of propionate. The viability of cells in buffer, and glucose-containing buffer, was found to be only insignificantly decreased by oxygen in the range from 0 to 500 mumoles of oxygen per g of wet cells.
mesh_terms: D000085:Acetates / Q000378:metabolism*; D000693:Anaerobiosis; D005947:Glucose / Q000378:metabolism; D005958:Glucosephosphates / Q000378:metabolism; D008293:Malates / Q000378:metabolism; D010100:Oxygen; D011422:Propionates / Q000378:metabolism*; D011424:Propionibacterium / Q000378:metabolism*; D011773:Pyruvates / Q000378:metabolism
chemical_list: D000085:Acetates; D005958:Glucosephosphates; D008293:Malates; D011422:Propionates; D011773:Pyruvates; D005947:Glucose; D010100:Oxygen