title: Tellurite-, tellurate-, and selenite-based anaerobic respiration by strain CM-3 isolated from gold mine tailings.
abstract: The newly discovered strain CM-3, a Gram-negative, rod-shaped bacterium from gold mine tailings of the Central Mine in Nopiming Provincial Park, Canada, is capable of dissimilatory anaerobic reduction of tellurite, tellurate, and selenite. CM-3 possesses very high level resistance to these oxides, both aerobically and anaerobically. During aerobic growth, tellurite and tellurate resistance was up to 1500 and 1000 µg/ml, respectively. In the presence of selenite, growth occurred at the highest concentration tested, 7000 µg/ml. Under anaerobic conditions, resistance was decreased to 800 µg/ml for the Te oxides; however, much like under aerobic conditions, growth with selenite still took place at 7000 µg/ml. In the absence of oxygen, CM-3 couples oxide reduction to an increase in biomass. Following an initial drop in viable cells, due to switching from aerobic to anaerobic conditions, there was an increase in CFU/ml greater than one order of magnitude in the presence of tellurite (6.6 × 10(3)-8.6 × 10(4) CFU/ml), tellurate (4.6 × 10(3)-1.4 × 10(5) CFU/ml), and selenite (2.7 × 10(5)-5.6 × 10(6) CFU/ml). A control culture without metalloid oxides showed a steady decrease in CFU/ml with no recovery. ATP production was also increased in the presence of each oxide, further indicating anaerobic respiration. Partial 16S rRNA gene sequencing revealed a 99.0 % similarity of CM-3 to Pseudomonas reactans.
authors.affiliation: Department of Microbiology, University of Manitoba, Winnipeg, MB, Canada.
authors.forename: Chris
authors.initials: C
authors.lastname: Maltman
authors.forename: Michele D
authors.initials: MD
authors.lastname: Piercey-Normore
authors.forename: Vladimir
authors.initials: V
authors.lastname: Yurkov
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism; D001421:Bacteria, Anaerobic / Q000145:classification / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism; D001483:Base Sequence; D019069:Cell Respiration; D019015:Geologic Sediments / Q000737:chemistry / Q000382:microbiology*; D006046:Gold / Q000032:analysis; D008906:Mining; D008969:Molecular Sequence Data; D010802:Phylogeny; D011549:Pseudomonas / Q000235:genetics; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D020887:Selenious Acid / Q000378:metabolism*; D013691:Tellurium / Q000378:metabolism*
chemical_list: D012336:RNA, Ribosomal, 16S; D006046:Gold; D000255:Adenosine Triphosphate; D020887:Selenious Acid; C026660:tellurous acid; D013691:Tellurium