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A novel octameric AMP‐forming acetyl‐CoA synthetase from the hyperthermophilic crenarchaeon Pyrobaculum aerophilum
Author(s) -
Bräsen Christopher,
Urbanke Claus,
Schönheit Peter
Publication year - 2005
Publication title -
febs letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.593
H-Index - 257
eISSN - 1873-3468
pISSN - 0014-5793
DOI - 10.1016/j.febslet.2004.12.016
Subject(s) - thermolabile , thermostability , hyperthermophile , biochemistry , recombinant dna , acetyl coa , enzyme , amino acid , biology , archaea , chemistry , gene
AMP‐forming acetyl‐CoA synthetases (ACSs) are ubiquitous in all three domains of life. Here, we report the first characterization of an ACS from a hyperthermophilic organism, from the archaeon Pyrobaculum aerophilum . The recombinant ACS, the gene product of ORF PAE2867, showed extremely high thermostability and thermoactivity at temperatures around 100 °C. In contrast to known monomeric or homodimeric mesophilic ACSs, the P. aerophilum ACS was a 610 kDa homooctameric protein, with a significant lower content of thermolabile (Cys, Asn, and Gln) and higher content of charged (Glu, Lys, and Arg) amino acids. Kinetic analyses revealed an unusual broad substrate spectrum for organic acids and an extremely high affinity for acetate ( K m 3 μM).