A geomicrobiological study of soils collected from auriferous areas of Argentina

Bacillus cereus, gold and associated elements in soil and other regolith samples from Tomakin Park Gold Mine in southeastern New South Wales, Australia

“…Several methods of matrix rotations, i.e., varimax, quartimax, equamax and promax, were tried, but varimax rotation with Kaiser normalization was found to be the most effective in separating the data, as also found by Melchior et al (1996). All calculations were made using SPSS version 11.0 (SPSS, 2001).…”

“…However, no geomicrobiological studies have been published on indicator organisms in Australia. The use of the soil bacterium Bacillus cereus as an indicator organism for Au and other metals has been explored in studies of different terrains in Belgium, China, Argentina and Mexico (Neybergh et al, 1991;Melchior et al, 1994Melchior et al, , 1996Wang et al, 1999). B. cereus is an aerobic sporeforming soil bacterium that displays a high metal and penicillin tolerance.…”

“…Its spores have been isolated from most soils and sediments in numbers of several hundred colony-forming units (CFUs) per gram dry weight of soil (Watterson, 1985). However, the spore counts in polymetallic soils, especially those with high Au concentrations, were up to several orders of magnitude higher, indicating an unambiguous association of bacterial population with polymetallic soils (Watterson, 1985;Neybergh et al, 1991;Melchior et al, 1994Melchior et al, , 1996Wang et al, 1999). Due to their high oxidation potentials, most Au(I) and Au(III) complexes can act as strong bactericides even at low concentrations (Karthikeyan and Beveridge, 2002).…”