It appears that arsenate reduction by the Desulfovibrio strain Ben-RA is catalyzed by an arsenate reductase that is encoded by a chromosomally-borne gene shown to be homologous to the arsC gene of the Escherichia coli plasmid, R773 ars system.
arsenate |
Chemist Steven A. Benner has expressed doubts that arsenate has replaced phosphate in the DNA of this organism.