An abnormally acidic TATA-binding protein from a hyperthermophilic archaeon.
The gene encoding the TATA-binding protein (PkTBP) from a hyperthermophilic archaeon, Pyrococcus sp. KOD1 (Pk), was cloned and sequenced. An open reading frame with homology to the conserved C-terminal core region of eukaryotic TBP was expressed in Escherichia coli. Specific DNA-binding activity of the recombinant PkTBP (190 amino acids, 21.36 kDa) was also demonstrated. Although it was composed of a structurally direct repeat sequence which is similar to eukaryotic TBP, the total net charge of archaeal TBP was amazingly negative (calculated isoelectric point (pI) was 4.66 and experimentally estimated pI was 4.8). A series of five Glu residues was found at the C terminus of archaeal TBP. These data strongly suggest that a positively charged protein is also involved in the transcription initiation event which might stabilize the structure of the genomic DNA under high-growth-temperature conditions.
Department of Biotechnology, Faculty of Engineering, Osaka University, Japan.
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N
Rashid
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M
Morikawa
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Imanaka
D000595:Amino Acid Sequence; D001105:Archaea / Q000235:genetics*; D001483:Base Sequence; D003001:Cloning, Molecular; D004269:DNA, Bacterial / Q000235:genetics / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D005798:Genes, Bacterial; D007526:Isoelectric Point; D008969:Molecular Sequence Data; D012091:Repetitive Sequences, Nucleic Acid; D017386:Sequence Homology, Amino Acid; D016385:TATA Box; D035181:TATA-Box Binding Protein; D014157:Transcription Factors / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism
D004269:DNA, Bacterial; D004268:DNA-Binding Proteins; D035181:TATA-Box Binding Protein; D014157:Transcription Factors