Organizational characteristics and information content of an archaeal genome: 156 kb of sequence from Sulfolobus solfataricus P2.
We have initiated a project to sequence the 3 Mbp genome of the thermoacidophilic archaebacterium Sulfolobus solfataricus P2. Cosmids were selected from a provisional set of minimally overlapping clones, subcloned in pUC18, and sequenced using a hybrid (random plus directed) strategy to give two blocks of contiguous unique sequence, respectively, 100,389 and 56,105 bp. These two contigs contain a total of 163 open reading frames (ORFs) in 26-29 putative operons; 56 ORFs could be identified with reasonable certainty. Clusters of ORFs potentially encode proteins of glycogen biosynthesis, oxidative decarboxylation of pyruvate, ATP-dependent transport across membranes, isoprenoid biosynthesis, protein synthesis, and ribosomes. Putative promoters occur upstream of most ORFs. Thirty per cent of the predicted strong and medium-strength promoters can initiate transcription at the start codon or within 10 nucleotides upstream, indicating a process of initial mRNA-ribosome contact unlike that of most eubacterial genes. A novel termination motif is proposed to account for 15 additional terminations. The two contigs differ in densities of ORFs, insertion elements and repeated sequences; together they contain two copies of the previously reported insertion sequence ISC 1217, five additional IS elements representing four novel types, four classes of long non-IS repeated sequences, and numerous short, perfect repeats.
Sensen
C W
CW
Canadian Institute for Advanced Research, Program in Evolutionary Biology, National Research Council of Canada, Halifax, Nova Scotia, Canada.
Klenk
H P
HP
Singh
R K
RK
Allard
G
G
Chan
C C
CC
Liu
Q Y
QY
Penny
S L
SL
Young
F
F
Schenk
M E
ME
Gaasterland
T
T
Doolittle
W F
WF
Ragan
M A
MA
Charlebois
R L
RL
D002876:Chromosomes, Bacterial; D003001:Cloning, Molecular; D003360:Cosmids; D004251:DNA Transposable Elements; D004269:DNA, Bacterial / Q000235:genetics; D016680:Genome, Bacterial; D008969:Molecular Sequence Data; D016366:Open Reading Frames; D012329:RNA, Bacterial; D012045:Regulatory Sequences, Nucleic Acid; D012091:Repetitive Sequences, Nucleic Acid; D017422:Sequence Analysis, DNA; D017385:Sequence Homology; D016944:Sulfolobus / Q000235:genetics*; D014158:Transcription, Genetic
D004251:DNA Transposable Elements; D004269:DNA, Bacterial; D012329:RNA, Bacterial