“…Laboratory studies have been conducted to elucidate the interactions of gold with microorganisms using gold(III) chloride- (Beveridge and Murray, 1976;Darnall et al, 1986;Greene et al, 1986;Watkins et al, 1987;Gee and Dudeney, 1988;Karamushka et al, 1990a, b;Dyer et al, 1994;Beveridge, 1994, 1996;Canizal et al, 2001;Kashefi et al, 2001;Karthikeyan and Beveridge, 2002;Nair and Pradeep, 2002;Ahmad et al, 2003;Nakajima, 2003;Tsuruta, 2004;Keim and Farina, 2005;Lengke et al, 2006aLengke et al, , b, c, 2007, gold(I) thiosulphate- (Lengke and Southam, 2005, 2006, 2007Lengke et al, 2006a), gold L-asparagine- (Southam et al, 2000), aurothiomalate-complexes (Higham et al, 1986) and colloidal gold-containing solutions (Karamushka et al, 1987b(Karamushka et al, , 1990bUlberg et al, 1992). In study with 30 different microorganisms (eight bacteria, nine actinomycetes, eight fungi and five yeasts, Nakajima (2003) found that the bacteria were more efficient in removing gold(I/III) complexes from solution than other groups of microorganisms.…”