TY - JOUR
AU - Schmidt, C.
AB - The crenarchaeon Pyrobaculum aerophilum is with an optimalgrowth temperature of 100 °C one of the most thermophilic organisms knownto possess an aerobic respiratory chain. The analysis of DNA sequences fromthe Pyrobaculum genome project lead to the identification of an openreading frame potentially coding for a Rieske iron-sulfur protein. Thecomplete gene (named parR) was cloned and sequenced. The deducedamino acid sequence displays unusual amino acid exchanges and a so farunknown sequence insertion. The N-terminus shows similarities to bacterialsignal sequences. Several forms of the gene were expressed in E.coli in order to verify the classification as a Rieske protein and tofacilitate biophysical studies. Soluble, thermo-stable proteins withcorrectly inserted iron-sulfur clusters were expressed from two versions ofthe gene. The Δ1–23 truncated holo-protein is redox active. Itdisplays the typical spectroscopic properties of a Rieske protein. The redoxpotential was determined to be +215 mV at pH 6.5 and is pH dependentabove pH 7.5 revealing the influence of two protonation equilibria with pKavalues of 8.1 and 9.8. Phylogenetic analysis demonstrates that the parRprotein clusters together with the two other available archaeal Rieskesequences from Sulfolobus on a separate branch of the phylogenetictree apart from the proteins from thermophilic bacteria like Aquifexand Thermus.
TI - A Novel Rieske Iron-Sulfur Protein from the Hyperthermophilic Crenarchaeon Pyrobaculum aerophilum: Sequencing of the Gene, Expression in E. coli and Characterization of the Protein
JF - Journal of Bioenergetics and Biomembranes
DO - 10.1023/A:1005447710894
DA - 2004-09-29
UR - https://www.deepdyve.com/lp/springer-journals/a-novel-rieske-iron-sulfur-protein-from-the-hyperthermophilic-DJXgzS8pQg
SP - 119
EP - 128
VL - 31
IS - 2
DP - DeepDyve
ER -