A new strictly anaerobic bacterium (strain BAL-1T) has been isolated from a reed bed at Ballarat Goldfields in Australia. The organism grew by reducing arsenate [As(V)] to arsenite [As(III)], using acetate as electron donor and carbon source; acetate alone did not support growth. When BAL-1T was grown with arsenate as the terminal electron acceptor, acetate could be replaced by pyruvate, l- and d-lactate, succinate, malate, and fumarate but not by H2, formate, citrate, glutamate, other amino acids, sugars, or benzoate. With acetate was the electron donor, arsenate could be replaced by nitrate or nitrite but not by sulfate, thiosulfate, or iron oxide. Nitrate was reduced to ammonia via nitrite. The doubling time for growth on acetate (5 mM) plus arsenate (5 mM) or nitrate (5 mM) was 4 h. The G+C content of the DNA is 49 mol%. The 16S rRNA sequence data for the organism support the hypothesis that this organism is phylogenetically unique and at present is the first representative of a new deeply branching lineage of the Bacteria. This organism is described as Chrysiogenes arsenatis gen. nov., sp. nov.
DowdleP. R., LavermanA. M., OremlandR. S.1996; Bacterial dissimilatory reduction of arsenic(V) to arsenic(III) in anoxic sediments. Appl. Environ. Microbiol 62:1664–1669
FialaG., WoeseC. R., LangworthyT. A., StetterK. O.1990; Flexistipes sinusarabici, a novel genus and species of eubacteria occurring in the Atlantis II Deep brines of the Red Sea. Arch. Microbiol 154:120–126
GlaubigR. A., GoldbergS.1988; Determination of inorganic arsenic (III) and arsenic (III plus V) using automated hydride-generation atomicabsorption spectrometry. Soil Sci. Soc. Am. J 52:536–537
LavermanA. M., BlumJ. S., SchaeferJ. K., PhillipsE. J. P., LovleyD. R., OremlandR. S.1995; Growth of strain SES-3 with arsenate and other diverse electron acceptors. Appl. Environ. Microbiol 61:3556–3561
LovleyD. R., PhillipsE. J. P.1988; Novel mode of microbial energy metabolism: organic carbon oxidation coupled to dissimilatory reduction of iron or manganese. Appl. Environ. Microbiol 54:1472–1480
MacyJ. M., LawsonS., DeMoll-DeckerH.1993; Bioremediation of selenium oxyanions in San Joaquin drainage water using Thauera selenatis in a biological reactor system. Appl. Microbiol. Biotechnol 40:588–594
MacyJ. M., MichelT. A., KirschD. G.1989; Selenate reduction by a Pseudomonas species: a new mode of anaerobic respiration. FEMS Microbiol. Lett 61:195–198
NelsonD. C., WaterburyJ. B., JannaschH. W.1984; DNA base composition and genome size of the prokaryotic symbiont in Riftia pachyptila(Pogonophora). FEMS Microbiol. Lett 24:267–271
RaineyF. A., DorschM., MorganH. W., StackebrandtE.1992; 16s rDNA analysis of Spirochaeta thermophila: its phylogenetic position and implications for the systematics of the order Spirochaetales. Syst. Appl. Microbiol 15:197–202
RechS. A., MacyJ. M.1992; The terminal reductases for selenate and nitrate respiration in Thauera selenatis are two distinct enzymes. J. Bacteriol 174:7316–7320
RossiniF. D., WagmanD. D., EvansW. H., LevineS., JaffeI.1952Selected values of chemical thermodynamic properties U.S. Department of Commerce; Washington, D.C:
WoeseC. R.1992 Prokaryote systematics: the evolution of a science. 2–18BalowsA., TriiperH. G., DworkinM., HarderW., SchleiferK.-H.edThe prokaryotes1 Springer-Verlag; New York: