An Extracellular Tetrathionate Hydrolase from the Thermoacidophilic Archaeon Acidianus Ambivalens with an Activity Optimum at pH 1.

ABSTRACT:

Background

The thermoacidophilic and chemolithotrophic archaeon Acidianus ambivalens is routinely grown with sulfur and CO(2)-enriched air. We had described a membrane-bound, tetrathionate (TT) forming thiosulfate:quinone oxidoreductase. Here we describe the first TT hydrolase (TTH) from Archaea.

Results

A. ambivalens cells grown aerobically with TT as sole sulfur source showed doubling times of 9 h and final cell densities of up to 8 × 10(8)/ml. TTH activity (≈0.28 U/mg protein) was found in cell-free extracts of TT-grown but not of sulfur-grown cells. Differential fractionation of freshly harvested cells involving a pH shock showed that about 92% of the TTH activity was located in the pseudo-periplasmic fraction associated with the surface layer, while 7.3% and 0.3% were p

SUBMITTER: Protze J 

PROVIDER: S-EPMC3128947 | biostudies-literature | 2011

REPOSITORIES: biostudies-literature