GROWTH OF STRAIN SES-3 WITH ARSENATE AND OTHER DIVERSE ELECTRON-ACCEPTORS

The selenate-respiring bacterial strain SES-3 was able to use a variet y of inorganic electron accepters to sustain growth. SES-3 grew with t he reduction of arsenate to arsenite, Fe(III) to Fe(II), or thiosulfat e to sulfide, It also grew in medium in which elemental sulfur, Mn(IV) , nitrite, trimethylamine N-oxide, or fumarate was provided as an elec tron acceptor. Growth on oxygen was microaerophilic. There was no grow th with arsenite or chromate, Washed suspensions of cells grown on sel enate or nitrate had a constitutive ability to reduce arsenate but wer e unable to reduce arsenite. These results suggest that strain SES-3 m ay occupy a niche as an environmental opportunist by being able to tak e advantage of a diversity of electron accepters.