Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Chlamydia trachomatis RNA polymerase alpha subunit: sequence and structural analysis.

ABSTRACT: We describe the cloning and sequence analysis of the region surrounding the gene for the alpha subunit of RNA polymerase from Chlamydia trachomatis. This region contains genes for proteins in the order SecY, S13, S11, alpha, and L17, which are equivalent to Escherichia coli and Bacillus subtilis r proteins. The incorporation of chlamydial alpha subunit protein into the E. coli RNA polymerase holoenzyme rather than its truncated variant lacking the amino terminus suggests the existence of structural conservation among alpha subunits from distantly related genera.

SUBMITTER: Gu L

PROVIDER: S-EPMC176926 | biostudies-other | 1995 May

REPOSITORIES: biostudies-other

ACCESS DATA

Json Xml

Publications

Chlamydia trachomatis RNA polymerase alpha subunit: sequence and structural analysis.

Gu L L Wenman W M WM Remacha M M Meuser R R Coffin J J Kaul R R

Journal of bacteriology 19950501 9

We describe the cloning and sequence analysis of the region surrounding the gene for the alpha subunit of RNA polymerase from Chlamydia trachomatis. This region contains genes for proteins in the order SecY, S13, S11, alpha, and L17, which are equivalent to Escherichia coli and Bacillus subtilis r proteins. The incorporation of chlamydial alpha subunit protein into the E. coli RNA polymerase holoenzyme rather than its truncated variant lacking the amino terminus suggests the existence of structu ...[more]

PMID: 7730299

Similar Datasets

Cloning and characterization of the RNA polymerase alpha-subunit operon of Chlamydia trachomatis.

Project description:We have cloned the chlamydial operon that encodes the initiation factor IF1, the ribosomal proteins L36, S13, and S11, and the alpha subunit of RNA polymerase. The genes for S11 and alpha are closely linked in Escherichia coli, Bacillus subtilis, and plant chloroplast genomes, and this arrangement is conserved in Chlamydia spp. The S11 ribosomal protein gene potentially encodes a protein of 125 amino acids with 41 to 42% identity over its entire length to its E. coli and B. subtilis homologs; the gene encoding the alpha subunit specifies a protein of 322 amino acids with 25 to 30% identity over its entire length to its E. coli and B. subtilis homologs. In a T7-based expression system in E. coli, the chlamydial alpha gene directed the synthesis of a 36-kDa protein. Mapping of the chlamydial mRNA transcript by RNase protection studies and by a combination of reverse transcription and the polymerase chain reaction demonstrates that IF1, L36, S13, S11, and alpha are transcribed as a polycistronic transcript.

| S-EPMC206856 | biostudies-other

Bacterial RNA polymerase subunit omega and eukaryotic RNA polymerase subunit RPB6 are sequence, structural, and functional homologs and promote RNA polymerase assembly.

Project description:Bacterial DNA-dependent RNA polymerase (RNAP) has subunit composition beta'betaalpha(I)alpha(II)omega. The role of omega has been unclear. We show that omega is homologous in sequence and structure to RPB6, an essential subunit shared in eukaryotic RNAP I, II, and III. In Escherichia coli, overproduction of omega suppresses the assembly defect caused by substitution of residue 1362 of the largest subunit of RNAP, beta'. In yeast, overproduction of RPB6 suppresses the assembly defect caused by the equivalent substitution in the largest subunit of RNAP II, RPB1. High-resolution structural analysis of the omega-beta' interface in bacterial RNAP, and comparison with the RPB6-RPB1 interface in yeast RNAP II, confirms the structural relationship and suggests a "latching" mechanism for the role of omega and RPB6 in promoting RNAP assembly.

| S-EPMC14680 | biostudies-literature

A regulator from Chlamydia trachomatis modulates the activity of RNA polymerase through direct interaction with the beta subunit and the primary sigma subunit.

Project description:The obligate intracellular human pathogen Chlamydia trachomatis undergoes a complex developmental program involving transition between two forms: the infectious elementary body (EB), and the rapidly dividing reticulate body (RB). However, the regulators controlling this development have not been identified. To uncover potential regulators of transcription in C. trachomatis, we screened a C. trachomatis genomic library for sequences encoding proteins that interact with RNA polymerase (RNAP). We report the identification of one such protein, CT663, which interacts with the beta and sigma subunits of RNAP. Specifically, we show that CT663 interacts with the flap domain of the beta subunit (beta-flap) and conserved region 4 of the primary sigma subunit (sigma(66) in C. trachomatis). We find that CT663 inhibits sigma(66)-dependent (but not sigma(28)-dependent) transcription in vitro, and we present evidence that CT663 exerts this effect as a component of the RNAP holoenzyme. The analysis of C. trachomatis-infected cells reveals that CT663 begins to accumulate at the commencement of the RB-to-EB transition. Our findings suggest that CT663 functions as a negative regulator of sigma(66)-dependent transcription, facilitating a global change in gene expression. The strategy used here is generally applicable in cases where genetic tools are unavailable.

| S-EPMC2720258 | biostudies-literature

Chlamydia trachomatis: genome sequence analysis of lymphogranuloma venereum isolates.

Project description:Chlamydia trachomatis is the most common cause of sexually transmitted infections in the UK, a statistic that is also reflected globally. There are three biovariants of C. trachomatis: trachoma (serotypes A-C) and two sexually transmitted pathovars; serotypes D-K and lymphogranuloma venereum (LGV). Trachoma isolates and the sexually transmitted serotypes D-K are noninvasive, whereas the LGV strains are invasive, causing a disseminating infection of the local draining lymph nodes. Genome sequences are available for single isolates from the trachoma (serotype A) and sexually transmitted (serotype D) biotypes. We sequenced two isolates from the remaining biotype, LGV, a long-term laboratory passaged strain and the recent "epidemic" LGV isolate-causing proctitis. Although the genome of the LGV strain shows no additional genes that could account for the differences in disease outcome, we found evidence of functional gene loss and identified regions of heightened sequence variation that have previously been shown to be important sites for interstrain recombination. We have used new sequencing technologies to show that the recent clinical LGV isolate causing proctitis is unlikely to be a newly emerged strain but is most probably an old strain with relatively new clinical manifestations.

| S-EPMC2134780 | biostudies-literature

High-resolution genotyping of Chlamydia trachomatis strains by multilocus sequence analysis.

Project description:Genotyping of Chlamydia trachomatis is limited by the low sequence variation in the genome, and no adequate method is available for analysis of the spread of chlamydial infections in the community. We have developed a multilocus sequence typing (MLST) system based on five target regions and compared it with analysis of ompA, the single gene most extensively used for genotyping. Sequence determination of 16 reference strains, comprising all major serotypes, serotypes A to L3, showed that the number of genetic variants in the five separate target regions ranged from 8 to 16. The genetic variation in 47 clinical C. trachomatis isolates of representative serotypes (14 serotype D, 12 serotype E, 11 serotype G, and 10 serotype K strains) was analyzed; and the MLST system detected 32 variants, whereas 12 variants were detected by using ompA analysis. Specimens of the predominant serotype, serotype E, were differentiated into seven genotypes by MLST but into only two by ompA analysis. The MLST system was applied to C. trachomatis specimens from a population of men who have sex with men and was able to differentiate 10 specimens of one predominant ompA genotype G variant into four distinct MLST variants. To conclude, our MLST system can be used to discriminate C. trachomatis strains and can be applied to high-resolution molecular epidemiology.

| S-EPMC1865860 | biostudies-literature

Global Multilocus Sequence Type Analysis of Chlamydia trachomatis Strains from 16 Countries.

Project description:The Uppsala University Chlamydia trachomatis multilocus sequence type (MLST) database (http://mlstdb.bmc.uu.se) is based on five target regions (non-housekeeping genes) and the ompA gene. Each target has various numbers of alleles-hctB, 89; CT058, 51; CT144, 30; CT172, 38; and pbpB, 35-derived from 13 studies. Our aims were to perform an overall analysis of all C. trachomatis MLST sequence types (STs) in the database, examine STs with global spread, and evaluate the phylogenetic capability by using the five targets. A total of 415 STs were recognized from 2,089 specimens. The addition of 49 ompA gene variants created 459 profiles. ST variation and their geographical distribution were characterized using eBURST and minimum spanning tree analyses. There were 609 samples from men having sex with men (MSM), with 4 predominating STs detected in this group, comprising 63% of MSM cases. Four other STs predominated among 1,383 heterosexual cases comprising, 31% of this group. The diversity index in ocular trachoma cases was significantly lower than in sexually transmitted chlamydia infections. Predominating STs were identified in 12 available C. trachomatis whole genomes which were compared to 22 C. trachomatis full genomes without predominating STs. No specific gene in the 12 genomes with predominating STs could be linked to successful spread of certain STs. Phylogenetic analysis showed that MLST targets provide a tree similar to trees based on whole-genome analysis. The presented MLST scheme identified C. trachomatis strains with global spread. It provides a tool for epidemiological investigations and is useful for phylogenetic analyses.

| S-EPMC4473235 | biostudies-literature

Sequence analysis of two temperature-sensitive mutations in the alpha subunit gene (rpoA) of Escherichia coli RNA polymerase.

Project description:The rpoA gene of Escherichia coli encodes the alpha subunit of the DNA-dependent RNA polymerase. Two mutant alleles, rpoA101 and rpoA112, both of which produce RNA polymerase with altered thermostability and reduced fidelity of transcription in vitro (Ishihama et al. (1980) J. Mol. Biol. 137, 137-150), have been analyzed in details. The mutations were found to be responsible for the temperature-sensitive growth by complementation test using a rpoA-expression plasmid. Each mutant allele was amplified from total cell DNA by PCR (polymerase chain reaction) and directly sequenced. Both the mutant rpoA genes were found to carry a single base transition which leads to a substitution of Cys for Arg at the position 191 (rpoA101) or 45 (rpoA112), respectively. Since the rpoA112 mutation causes the defect in RNA polymerase assembly (Kawakami & Ishihama (1980) Biochemistry 19, 3491-3495), the amino-terminal region of alpha including the position 45 was considered to play an important role in subunit assembly.

| S-EPMC332388 | biostudies-other

Molecular analysis of RNA polymerase alpha subunit gene from Streptomyces coelicolor A3(2).

Project description:The rpoA gene, encoding the alpha subunit of RNA polymerase, was cloned from Streptomyces coelicolor A3(2). It is preceded by rpsK and followed by rplQ, encoding ribosomal proteins S11 and L17, respectively, similar to the gene order in Bacillus subtilis. The rpoA gene specifies a protein of 339 amino acids with deduced molecular mass of 36,510 Da, exhibiting 64.3 and 70.7% similarity over its entire length to Escherichia coli and B. subtilis alpha subunits, respectively. Using T7 expression system, we overexpressed the S. coelicolor alpha protein in E. coli. A small fraction of this protein was found to be assembled into E. coli RNA polymerase. Antibody against S. coelicolor alpha protein crossreacted with that of B. subtilis more than with the E. coli alpha subunit. The ability of recombinant alpha protein to assemble beta and beta' subunits into core enzyme in vitro was examined by measuring the core enzyme activity. Maximal reconstitution was obtained at alpha2:beta+beta' ratio of 1:2.3, indicating that the recombinant alpha protein is fully functional for subunit assembly. Similar results were also obtained for natural alpha protein. Limited proteolysis with endoproteinase Glu-C revealed that S. coelicolor alpha contains a tightly folded N-terminal domain and the C-terminal region is more protease-sensitive than that of E. coli alpha.

| S-EPMC146286 | biostudies-other

Cloning and sequence analysis of the Chlamydia trachomatis spc ribosomal protein gene cluster.

Project description:We identified and sequenced a segment of Chlamydia trachomatis chromosomal DNA that shows homology to the Escherichia coli spc and distal region of the S10 ribosomal protein (r-protein) operons. Its sequence revealed a high degree of nucleotide and operon context conservation with the E. coli r-protein genes. The C. trachomatis spec operon contains the r-protein genes for L14, L24, L5, S8, L6, L18, S5, L15, and Sec Y along with the genes for r-proteins L16, L29, and S17 of the S10 operon. The two operons are separated by a 16-bp intragenic region which contains no transcription signals. However, a putative promoter for the transcription of the spc operon was found 162 nucleotides upstream of the CtrL14e start site; it revealed significant homology to the E. coli consensus promoter sequences. Interestingly, our results indicate the absence of any structure resembling an EcoS8 regulatory target site on C. trachomatis spc mRNA in spite of significant amino acid identity between E. coli and C. trachomatis r-proteins. Also, the intrinsic aminoglycoside resistance in C. trachomatis is unlikely to be mediated by CtrL6e since E. coli expressing CtrL6e remained susceptible to gentamicin (MIC less than 0.5 micrograms/ml).

| S-EPMC206413 | biostudies-other

Prophylactic Multi-Subunit Vaccine against Chlamydia trachomatis: In Vivo Evaluation in Mice.

Project description:Chlamydia trachomatis is the most frequent sexually-transmitted disease-causing bacterium. Urogenital serovars of this intracellular pathogen lead to urethritis and cervicitis. Ascending infections result in pelvic inflammatory disease, salpingitis, and oophoritis. One of 200 urogenital infections leads to tubal infertility. Serovars A-C cause trachoma with visual impairment. There is an urgent need for a vaccine. We characterized a new five-component subunit vaccine in a mouse vaccination-lung challenge infection model. Four recombinant Pmp family-members and Ctad1 from C. trachomatis serovar E, all of which participate in adhesion and binding of chlamydial elementary bodies to host cells, were combined with the mucosal adjuvant cyclic-di-adenosine monophosphate. Intranasal application led to a high degree of cross-serovar protection against urogenital and ocular strains of C. trachomatis, which lasted at least five months. Critical evaluated parameters were body weight, clinical score, chlamydial load, a granulocyte marker and the cytokines IFN-γ/TNF-α in lung homogenate. Vaccine antigen-specific antibodies and a mixed Th1/Th2/Th17 T cell response with multi-functional CD4+ and CD8+ T cells correlate with protection. However, serum-transfer did not protect the recipients suggesting that circulating antibodies play only a minor role. In the long run, our new vaccine might help to prevent the feared consequences of human C. trachomatis infections.

| S-EPMC8226540 | biostudies-literature

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data