Differential stability of TATA box binding proteins from archaea with different optimal growth temperatures.
The TATA box binding protein (TBP) is involved in promoter recognition, the first step of transcription initiation. TBP is universally conserved and essential in archaea and eukaryotes. In archaea, TBPs have to be stable and to function in species that cover an extremely wide range of optimal growth temperatures (OGTs), from below 0 degrees C to more than 100 degrees C. Thus, the archaeal TBP family is ideally suited to study the evolutionary adaptation of proteins to an extremely wide range of temperatures. We characterized the thermostability of one mesophilic and one thermophilic TBP by infrared spectroscopy. Transition temperatures (T(m)s) of thermal unfolding have been determined using TBPs from Methanosarcina mazei (OGT 37 degrees C) and from Methanothermobacter thermautotrophicus (OGT 65 degrees C). Furthermore, the influence of protein and salt concentration on thermostability has been characterized. Together with previous studies, our results reveal that the T(m)s of archaeal TBPs are closely correlated with the OGTs of the respective species. Noteworthy, this is also true for the TBP from M. mazei representing the first characterized TBP from a mesophilic archaeon. In contrast, the only characterized eukaryotic TBP of the mesophilic plant Arabidopsis thaliana has a T(m) more than 40 degrees C above the OGT.
Institut für Biophysik, Johann Wolfgang Goethe-Universität Frankfurt, Max-von-Laue-Str. 1, 60438 Frankfurt am Main, Germany.
Annette
A
Kopitz
Jörg
J
Soppa
Carsten
C
Krejtschi
Karin
K
Hauser
D000064:Acclimatization; D017360:Arabidopsis / Q000737:chemistry / Q000254:growth & development / Q000502:physiology; D019843:Archaeal Proteins / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification; D003001:Cloning, Molecular; D004926:Escherichia coli / Q000235:genetics; D017013:Methanobacteriaceae / Q000737:chemistry / Q000254:growth & development / Q000502:physiology*; D017020:Methanosarcina / Q000737:chemistry / Q000254:growth & development / Q000502:physiology*; D008958:Models, Molecular; D010940:Plant Proteins / Q000737:chemistry; D011189:Potassium Chloride / Q000737:chemistry; D017510:Protein Folding; D055550:Protein Stability; D013055:Spectrophotometry, Infrared; D035181:TATA-Box Binding Protein / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification; D013696:Temperature; D044366:Transition Temperature
D019843:Archaeal Proteins; D010940:Plant Proteins; D035181:TATA-Box Binding Protein; D011189:Potassium Chloride