We purified from crude extracts of the hyperthermophilic crenarchaeon Sulfolobus solfataricus a protease that is able to hydrolyse proteins with a pH optimum of 7.5 and a temperature optimum of 70 degrees C. Assays in the presence of classical protease inhibitors showed that the hydrolytic activity is sensitive to thiol-blocking reagents. Fluorescence assays using synthetic peptides demonstrate...

Sulfolobus solfataricus secretes an acid-resistant alpha-amylase (amyA) during growth on starch as the sole carbon and energy source. Synthesis of this activity is subject to catabolite repression. To better understand alpha-amylase function and regulation, the structural gene was identified and disrupted and the resulting mutant was characterized. Internal alpha-amylase peptide sequences obtai...

The core structure of membrane lipids of archaea have some unique properties that permit archaea to be distinguished from the others, i.e. bacteria and eukaryotes. (S)-2,3-Di-O-geranylgeranylglyceryl phosphate synthase, which catalyzes the transfer of a geranylgeranyl group from geranylgeranyl diphosphate to (S)-3-O-geranylgeranylglyceryl phosphate, is involved in the biosynthesis of archaeal m...

Mercuric ion, Hg(II), inactivates generalized transcription in the crenarchaeote Sulfolobus solfataricus. Metal challenge simultaneously derepresses transcription of mercuric reductase (merA) by interacting with the archaeal transcription factor aMerR. Northern blot and primer extension analyses identified two additional Hg(II)-inducible S. solfataricus genes, merH and merI (SSO2690), located o...