An insertion element of the extremely thermophilic archaeon Sulfolobus solfataricus transposes into the endogenous beta-galactosidase gene.
Three phenotypically stable mutants of the extremely thermophilic archaeon Sulfolobus solfataricus have been isolated by screening for beta-galactosidase negative colonies on plates with X-Gal (5-bromo-4-chloro-3-indolyl-beta-D- galactopyranoside). From one of these mutants an insertion element, designated ISC1217, was isolated and characterized. Sequence analysis of ISC1217 and of the regions adjacent to the insertion site in the beta-galactosidase gene revealed features typical of a transposable element: ISC1217 contained terminal inverted repeats and was flanked by a direct repeat of 6 bp. The 1147 bp sequence contained an open reading frame encoding a putative protein of 354 amino acid residues and, overlapping this, two smaller open reading frames on the opposite strand. There were approximately 8 copies of the insertion element in the S. solfataricus genome. ISC1217 did not cross-hybridize with DNA of other Sulfolobus species. All three independently isolated beta-galactosidase mutants of S. solfataricus arose by transposition of ISC1217 or a related element.
Schleper
C
C
Max-Planck-Institut für Biochemie, Martinsried, Germany.
Röder
R
R
Singer
T
T
Zillig
W
W
D000595:Amino Acid Sequence; D001483:Base Sequence; D015139:Blotting, Southern; D004251:DNA Transposable Elements; D004269:DNA, Bacterial; D008969:Molecular Sequence Data; D016296:Mutagenesis; D016366:Open Reading Frames; D010641:Phenotype; D012091:Repetitive Sequences, Nucleic Acid; D016944:Sulfolobus / Q000201:enzymology / Q000235:genetics*; D001616:beta-Galactosidase / Q000235:genetics*
D004251:DNA Transposable Elements; D004269:DNA, Bacterial; D001616:beta-Galactosidase