Ni2+, Fe2+ and Cu2+ were attractants and aspartate was an apparent repellent for Leptospirillum ferrooxidans, a behaviour opposite to that for Escherichia coli. Membranes from L. ferrooxidans contained proteins with a molecular mass in the range of 80 kDa which were methylated in vitro. Methylation was stimulated in the presence of a membrane-free extract from E. coli, showing the response patt...

The obligately autotrophic acidophile Thiobacillus ferrooxidans was grown on elemental sulfur in anaerobic batch cultures, using ferric iron as an electron acceptor. During anaerobic growth, ferric iron present in the growth media was quantitatively reduced to ferrous iron. The doubling time in anaerobic cultures was approximately 24 h. Anaerobic growth did not occur in the absence of elemental...

Cellular protein, pH, dissolved oxygen concentration, and static surface tension were measured during growth of Thiobacillus acidophilus on elemental sulfur in the absence and presence of up to 5,000 mg of Tween 80 per liter. The decrease in pH and the increase in sulfate production were observed to be less accurate measurements of growth when compared with the increase in cellular protein. The...

Biosorption of each of the heavy metals, Zn(II) and Cu(II), and of the binary mixture of these two metal ions by the indigenous Thiobacillus thiooxidans was investigated in this study. Equilibrium concentration (qm) and dissociation constant (Kd) were calculated by fitting the experimental data with the Langmuir isotherms. The effects of pH, pretreatment of biomass, and temperature on the amoun...

It is shown that there exists in the autotrophic bacterium Thiobacillus thiooxidans a measurable oxygen uptake in the absence of the specific nutrient (sulfur). This respiration is shown to be due to the utilization of organic materials which must have been previously synthesized by the chemosynthetic process, providing evidence that autotrophic bacteria contain a dissimilatory process which in...

The composition of bacterial populations in copper bioleaching systems was investigated by analysis of DNA obtained either directly from ores or leaching solutions or after laboratory cultures. This analysis consisted of the characterization of the spacer regions between the 16 and 23S genes in the bacterial rRNA genetic loci after PCR amplification. The sizes of the spacer regions, amplified f...

Background and Purpose: The Phytoremediation efficiency of heavy metals is one of the important points in environmental studies. This research was conducted to investigate the effect of cow manure, elemental sulfur, and EDTA on Cd uptake by Indian mustard in a Cd-polluted soil in the presence of Thiobacillus thiooxidans. Materials and Methods: Treatments consisted of applying cow manure (0, 5,...