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W D Reiter

Publications and source records attributed to W D Reiter.

24 records · Page 2Linked to original sources
PubMed1988

Transcription termination in the archaebacterium Sulfolobus: signal structures and linkage to transcription initiation.

The precise map positions were determined for the 3'-termini of five transcripts of the Sulfolobus virus-like particle SSV1. In all cases analyzed, these 3'-termini mapped immediately downstream of a sequence TTTTTYT which was part of a pyrimidine-rich region of 16-19 nucleotides length. No correlation was evident between the position of the 3'-termini and possible secondary structures within the RNA. In two cases, the 3'-termini of SSV1 transcripts mapped in the immediate vicinity of transcriptional initiation sites suggesting that transcription termination can be linked to the re-initiation of RNA synthesis.

Archaea↗
PubMed1988

Analysis of transcription in the archaebacterium Sulfolobus indicates that archaebacterial promoters are homologous to eukaryotic pol II promoters.

The 5'-termini were precisely mapped for five constitutive and one UV-inducible transcript from the Sulfolobus virus-like particle SSV1. The comparison of the DNA sequences around these transcriptional initiation sites revealed the presence of two conserved sequence elements: a trinucleotide sequence close to the initiation site itself and an AT-rich hexanucleotide sequence centered about 26 nucleotides upstream of it. Similar DNA sequences were found upstream of the transcriptional start sites for the ribosomal RNA genes in Sulfolobus and upstream of transcriptional start sites in other archaebacteria, allowing the derivation of a general consensus sequence for archaebacterial promoters. This consensus sequence is unlike that found in eubacteria but it resembles promoters recognized by eukaryotic RNA polymerase II.

Archaea↗
PubMed1987

Putative promoter elements for the ribosomal RNA genes of the thermoacidophilic archaebacterium Sulfolobus sp. strain B12.

In Sulfolobus sp. strain B12, single-copy genes encode the three ribosomal RNAs. The genes for the 16S rRNA and for the 23S rRNA are closely linked but separated from the 5S rRNA gene. Transcription of the 16S/23S rRNA gene cluster starts 139 nucleotides upstream of the 5'-end of mature 16S rRNA. For the 5S rRNA gene the point of transcription initiation coincides with the 5'-end of mature 5S rRNA. The comparison of the upstream regions for these transcriptional start sites shows the presence of a completely conserved trinucleotide sequence around the point of transcription initiation and a completely conserved octanucleotide sequence about 22 nucleotides upstream of it. These sequences are only moderately homologous to putative promoter elements for stable RNA genes in the closely related archaebacterium Thermoproteus tenax (1), but they are very similar to corresponding sequences in the distantly related archaebacterium Methanococcus vannielii (2). The consensus sequence found for Sulfolobus and Methanococcus could therefore constitute the archetype of an archaebacterial promoter for stable RNA genes.

Archaea↗
PubMed1987

Gene expression in archaebacteria: physical mapping of constitutive and UV-inducible transcripts from the Sulfolobus virus-like particle SSV1.

The transcription of the genome of the UV-inducible Sulfolobus virus-like particle SSV1 was studied. Eight different transcripts could be distinguished by Northern analysis that were present in uninduced cells and the coordinately increased in amount after UV induction of SSV1. Using single-stranded DNA probes from different parts of the genome, the approximate map positions of these RNAs and the directions of transcription were determined. In two cases, terminator read-through resulted in the formation of more than one RNA species from a single 5' end and therefore the eight different RNAs corresponded to only five different transcriptional starts. Two RNAs sharing a common 5' end encode SSV1 structural proteins. The 5' end of these transcripts was determined by S1 nuclease analysis. About 20 nucleotides upstream of the transcriptional start of these RNAs, there is an AT-rich region resembling putative promoter sequences which have been found at a similar distance 5' to the genes encoding stable RNAs in Thermoproteus. In addition to the eight constitutive transcripts, a UV-inducible RNA of 0.3 kb was mapped on the SSV1 genome. In contrast to all other RNAs, it was not detectable in uninduced cells and it is expressed shortly before the amplification and packaging of the SSV1 genome commences.

Base Sequence↗
PubMed1984

SAV 1, a temperate u.v.-inducible DNA virus-like particle from the archaebacterium Sulfolobus acidocaldarius isolate B12.

Sulfolobus acidocaldarius, strain B12, which harbours a double-stranded DNA species both as a plasmid and in a linear form, which is integrated at a specific site of the chromosome, produces virus-like particles upon u.v. irradiation. These particles contain the same circular DNA and a number of coat proteins and are probably surrounded by a lipid membrane. They are lemon shaped, 100 x 60 nm in size and carry tail structures at one pole. The host cell recovers and remains lysogenic after virus production. Though a large fraction of liberated particles is found attached to structures derived from the cells, neither adsorption nor infection of a number of Sulfolobus isolates has so far been observed.

Journal Article↗