Aquificae

Microbe Profile: Aquifex aeolicus: an extreme heat-loving bacterium that feeds on gases and inorganic chemicals

“…Most of the genes seem to be organized within operons, but with an unexpected composition, and numerous genes overlap. Many of the genes that encode pathway constituents (or even subunits of the same complex or enzyme) are scattered around the genome and are thus encoded separately rather than being co-transcribed [2, 3].…”

“…‘ A. aeolicus ’ is a Knallgas bacterium, a microaerophilic respiratory microorganism obtaining its energy from hydrogen, but it can also oxidize reduced inorganic sulphur compounds (elemental sulphur and thiosulphate) [2–4]. In serum bottles, a maximum biomass of 0.9 OD 620 units is reached after 10 h of growth (on H 2 /O 2 ).…”

“…aeolicus ’ have led to the discovery or characterization of new metabolic pathways and proteins. Examples of this include the prediction that carbon assimilation is done via a hybrid pathway (see graphical abstract and below [7]), the discovery of an unknown RNase P enzyme involved in tRNA maturation [3], and the characterization of Soe, a new type of membrane-bound sulphite dehydrogenase [8]. Thermal adaptation and molecular stability are achieved by a combination of factors, including the synthesis of ionic-compatible solutes which protect proteins from heat denaturation, a higher degree of protein oligomerization, and the presence of disulphide bonds.…”