title: Sequence and transcriptional analysis of groES and groEL genes from the thermophilic bacterium Clostridium thermocellum.
abstract: The groESL operon from Clostridium thermocellum (Ct) has been isolated and sequenced, revealing two ORFs of 285 and 1626 nt, separated by 48 nt. The first ORF encoded a 94-aa 10.6-kDa GroES homologue; the second encoded a 541-aa polypeptide of 57.6 kDa, that exhibited 61% and 77% sequence identity with GroEL from Escherichia coli (Ec) and Clostridium acetobutylicum (Ca), respectively. A putative tsp, preceded by -10 and -35 consensus promoters, was identified upstream of groES. This was followed by an inverted repeat observed previously in bacterial heat shock genes. A 15-nt palindrome characteristic of a Rho-independent transcription terminator, was located downstream of groEL. The first nt of the groES translational start codon was preceded (7 nt) by a putative RBS (AGGAGG); a second RBS sequence was located 8 nt upstream of the groEL start. Production of GroE homologues by Ct was constitutive, but was enhanced significantly during a temperature upshift from 60 degrees C to 70 degrees C. The Ct GroEL, expressed in Ec as a fusion protein with GST, was purified, free of contaminating Ec GroEL.
authors.affiliation: Department of Cellular Physiology, The Babraham Institute, Cambridge, UK.
authors.forename: A
authors.initials: A
authors.lastname: Ciruela
authors.forename: S
authors.initials: S
authors.lastname: Cross
authors.forename: R B
authors.initials: RB
authors.lastname: Freedman
authors.forename: G P
authors.initials: GP
authors.lastname: Hazlewood
mesh_terms: D015152:Blotting, Northern; D018835:Chaperonin 10 / Q000096:biosynthesis / Q000235:genetics*; D018834:Chaperonin 60 / Q000096:biosynthesis / Q000235:genetics*; D003001:Cloning, Molecular; D003013:Clostridium / Q000235:genetics*; D004926:Escherichia coli / Q000235:genetics; D015964:Gene Expression Regulation, Bacterial; D005798:Genes, Bacterial; D008969:Molecular Sequence Data; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis / Q000235:genetics; D017422:Sequence Analysis, DNA; D012689:Sequence Homology, Nucleic Acid; D014158:Transcription, Genetic
chemical_list: D018835:Chaperonin 10; D018834:Chaperonin 60; D011993:Recombinant Fusion Proteins