Bioleaching microbes

From BioMineWiki

The microbes that are found in bioleaching environments are of two types: those that produce leaching chemicals ("true" bioleaching microbes) and those that do not produce leaching chemicals but support "true" bioleaching microbes - bioleaching supporters. In a consortium, bioleaching supporters assist those microbes producing leaching reagents by for example feeding on, and thereby removing, organic waste products that otherwise would build up and be detrimental to said "true" bioleaching microbes.

Prokaryotes are common while eukaryotes are rare

Even though all (?) microbes used in commercial plants for bioleaching are prokaryotes (bacteria and archaea), bioleaching eukaryotes exist too. These organisms often excrete organic acids which may act as leaching agents. Research on metal leaching of electronic scrap by bioleaching fungi has been performed with a certain degree of success. {Brandl, 2001 #9}

Bioleaching lichens

Comparison between "true" bioleachers, supporters and humans

Reasons why "true" bioleachers may not thrive

Sub-optimal growth conditions are attributable to at least the following:

1. incorrect pH conditions;
2. a lack of critical macro- and micro-nutrients;
3. a high ionic strength or total salt content
4. the presence of dissolved or entrained organic compounds with inhibitory effects on microbial growth;
5. carbon- or oxygen-limiting conditions

Acid streamers in the Cae Coch pyrite mine in Wales. By courtesy of Barrie Johnson	Acid streamers in the Cae Coch pyrite mine in Wales. By courtesy of Barrie Johnson	Acid streamers in the Cae Coch pyrite mine in Wales. By courtesy of Barrie Johnson	Acid streamers in the Cae Coch pyrite mine in Wales. By courtesy of Barrie Johnson
Acidophilic flagellate PR1 by courtesy of Barrie Johnson ‎	Acidithiobacilus thiooxidans (a mesophlic S-oxidiser) by courtesy of Barrie Johnson	A strain of Sulfobacillus acidophilus (Fe- and S-oxidising moderate thermophile) by courtesy of Barrie Johnson	This is a novel Fe-oxidising moderate thermophile we are just describing - proposed name Ferrit. By courtesy of Barrie Johnson
An Acidocella sp. (heterotrophic mesophile)by courtesy of Barrie Johnson	An unclassified mesophilic iron-oxidiser (an actinobacterium, related to Ferrimicrobium)by courtesy of Barrie Johnson	Leptospirillum ferrooxidans, a mesophilic Fe-oxidiser by courtesy of Barrie Johnson	Bioleaching microbes in a Swedish news programme about Biomine