Immobilization of free ionic gold and L-asparagine complexed ionic gold by Sporosarcina ureae: The importance of organo-gold complexes in gold mobility

摘要: Sporosarcina ureae was able to grow in the presence of up 10-ppm L-asparagine complexed gold. However, 10 ppm Au found be highly toxic ureae, killing 109 bacteria/mL within a few seconds. To compare effects these responses on gold mobility, an vitro bacterial biofilm model developed examine interaction between and ionic or complexes gravity-fed columns. The immobilization 80% 90% over period one week. But, as available cellular reactive sites became saturated, decreased 14% two weeks. In L-asparagine-gold system, cytoplasm occurred at high rate (80% 90%) throughout experiment, with limited toxicity towards ureae. detoxification L-asparagine-complexed associated low molecular weight, i.e, <5,000 dalton (atomic mass unit), intracellular protein fraction. This peptide-complexed would allow for continued biogeochemical cycling under ambient (<100°C) surface near-surface conditions.