16s and 23s components in the ribosomal ribonucleic acid of Rhodopseudomonas spheroides.
Ontology highlight
ABSTRACT:
SUBMITTER: Szilagyi JF
PROVIDER: S-EPMC1186774 | biostudies-other | 1968 Sep
REPOSITORIES: biostudies-other
Similar Datasets
Project description:PurposeTo clarify the short-term effect of topical anesthetics on 16S ribosomal ribonucleic acid amplicon sequencing results in ocular surface microbiome research.MethodsBoth eyes of 24 eligible volunteers undergoing general anesthesia were sampled. Before sampling, a drop of artificial tears or a drop of topical anesthetic was applied in a randomized way. By using artificial tears as a control, we assured blinding of the executer and took a potential diluting effect into account. Bacterial DNA was extracted using the QIAGEN RNeasy PowerMicrobiome Kit with specific adaptations. Amplified DNA was sequenced with the Illumina MiSeq sequencing platform.ResultsFour sample pairs were excluded due to low yield of bacterial DNA. In the remaining 20 sample pairs, no differences were observed with topical anesthetics at the levels of amplicon sequence variants (ASVs), phylum, genera, or alpha and beta diversity. Weighted UniFrac distance confirmed that the intraindividual distance between the right and left eye was smaller than the effect of the topical anesthetic. Interestingly, however, we identified Cutibacterium as a potential discriminative biomarker for topical anesthetic use. Overall, a significantly higher number of observed reads were assigned to genera with Gram-positive characteristics.ConclusionsBased on our targeted, double-blinded, within-subject study, topical anesthetics do not affect the overall sequencing results but display a specific effect on Cutibacterium. When comparing research results, the impact of topical anesthetics on prevalence and abundance of Cutibacterium should be considered.Translational relevanceUnderstanding and standardization of sampling techniques are indispensable to properly execute clinical microbiome research.
| S-EPMC8899854 | biostudies-literature
Project description:Background and aimSupplementation of AKBISprob (developed in a previous study) in feed can improve production efficiency and poultry health, especially laying hens. In addition, it can also increase cellulolytic lactic acid bacteria (LAB) in chicken intestines, but these bacteria are still unknown; thus, they need to be identified. This study aimed to identify cellulolytic LAB in the intestines of laying hens administered AKBISprob based on 16S ribosomal ribonucleic acid (16S rRNA) gene analysis.Materials and methodsThe samples used in this study were 13 LAB isolates from the intestines of laying hens that were given AKBISprob 4%. Cellulolytic LAB DNA was isolated and 16S rRNA gene was amplified by polymerase chain reaction, followed by sequencing, bioinformatics analysis, and phylogenetic tree construction.ResultsFrom 10 cellulolytic LAB isolates with a clear zone of >6 mm, four were selected and their DNA was amplified with BaCF and UniB primers ~1500 bp DNA fragments. Of these, the P31H62 isolate was genetically close to Enterococcus hirae strain 1-1X-16 with 92.90% maximum identity, the P33S52 isolate had homology with Enterococcus mundtii strain ZU 26 with 96.76% maximum identity, and the P33S62 isolate was closely related to E. hirae strain SJ3 with 72.96% maximum identity. The phylogenetic tree revealed that the cellulolytic LAB isolates P31H62 and P33S52 were in one cluster closely related to the genus Enterococcus.ConclusionThis study suggests that the isolates P31H62, P33S62, and P33S52 from the intestines of laying hens administered 4% AKBISprob are cellulolytic LAB belonging to the genus Enterococcus.
| S-EPMC9394149 | biostudies-literature
Project description:ObjectiveWe aim to evaluate the accuracy of the 16S ribosomal ribonucleic acid (rRNA) gene polymerase chain reaction (PCR) test in the diagnosis of bloodstream infections through a systematic review and meta-analysis.MethodsA computerized literature search was conducted to identify studies that assessed the diagnostic value of 16S rRNA gene PCR test for bloodstream infections. Study quality was assessed using the revised Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool. We calculated the sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR) and their 95% confidence intervals (95% CI) for each study. Summary receiver operating characteristic (SROC) curve was used to summarize overall test performance. Statistical analysis was performed in Meta-DiSc 1.4 and Stata/SE 12.0 software.ResultsTwenty-eight studies were included in our meta-analysis. Using random-effect model analysis, the pooled sensitivity, specificity, PLR, NLR, and DOR were 0.87 (95% CI, 0.85-0.89), 0.94 (95% CI, 0.93-0.95), 12.65 (95% CI, 8.04-19.90), 0.14 (95% CI, 0.08-0.24), and 116.76 (95% CI, 52.02-262.05), respectively. The SROC curve indicated that the area under the curve (AUC) was 0.9690 and the maximum joint sensitivity and specificity (Q*) was 0.9183. In addition, heterogeneity was statistically significant but was not caused by the threshold effect.ConclusionExisting data suggest that 16S rRNA gene PCR test is a practical tool for the rapid screening of sepsis. Further prospective studies are needed to assess the diagnostic value of PCR amplification and DNA microarray hybridization of 16S rRNA gene in the future.
| S-EPMC4440735 | biostudies-literature
Project description:Extracts of Rhodopseudomonas spheroides contain two ferrochelatases: one is soluble and forms metalloporphyrins from deuteroporphyrin and haematoporphyrin; the other is particulate and forms metalloporphyrins from protoporphyrin, mesoporphyrin, deuteroporphyrin and haematoporphyrin. Neither enzyme incorporates Mg(2+) into porphyrins or Fe(2+) into porphyrin cytochrome c. By using the particulate enzyme, plots of 1/v versus 1/s when one substrate was varied and the other kept constant showed that neither substrate affected the K(m) of the other. The suggested sequential mechanism for the reaction is supported by derivative plots of slopes and intercepts. The K(m) for deuteroporphyrin was 21.3mum and that for Co(2+) was 6.13mum. The enzyme incorporated Co(2+), Fe(2+), Zn(2+), Ni(2+) and Mn(2+); Cd(2+) was not incorporated and was an inhibitor, competitive with respect to Co(2+), non-competitive with respect to deuteroporphyrin. The K(i) for Cd(2+) was 0.73mum. Ferrochelatase was inhibited by protohaem, non-competitively with respect to Co(2+) or with respect to deuteroporphyrin. Inhibition by magnesium protoporphyrin was non-competitive with respect to deuteroporphyrin, uncompetitive with respect to Co(2+). The inhibitory concentrations of the metalloporphyrins are lower than those required for the inhibition of delta-aminolaevulate synthetase by protohaem. Fe(2+) is not incorporated aerobically into porphyrins unless an electron donor, succinate or NADH, is supplied; the low aerobic rate of metalloporphyrin synthesis obtained is insensitive to rotenone and antimycin. The rate of Fe(3+) incorporation increases as anaerobic conditions are achieved.
| S-EPMC1179374 | biostudies-other
Project description:The RNA of the blue-green alga Anacystis nidulans contains three ribosomal RNA species with molecular weights of 0.56x10(6), 0.9x10(6), and 1.1x10(6) if the RNA is extracted in the absence of Mg(2+). The 0.9x10(6)mol.wt. rRNA is extremely slowly labelled in (32)P-incorporation experiments. This rRNA may be a cleavage product of the 1.1x10(6)mol.wt. rRNA from the ribosomes of cells in certain physiological states (e.g. light-deficiency during growth). The cleavage of the 1.1x10(6)mol.wt. rRNA during the extraction procedure can be prevented by the addition of 10mm-MgCl(2). (32)P-pulse-labelling studies demonstrate the rapid synthesis of two ribosomal precursor RNA species. One precursor RNA migrating slightly slower than the 1.1x10(6)mol.wt. rRNA appears much less stable than the other precursor RNA, which shows the electrophoretic behaviour of the 0.7x10(6)mol.wt. rRNA. Our observations support the close relationship between bacteria and blue-green algae also with respect to rRNA maturation. The conversion of the ribosomal precursor RNA species into 0.56x10(6)- and 1.1x10(6)-mol.wt. rRNA species requires Mg(2+) in the incubation medium.
| S-EPMC1174049 | biostudies-other
Project description:Differentiation between Mycobacterium tuberculosis and M. avium is helpful for the treatment of disseminated mycobacterial infection in AIDS patients. This can traditionally be done by time-consuming biochemical tests or with Accuprobe. Previously, PCR restriction enzyme analysis (PCR-REA) of the 16S-23S rRNA gene spacer was shown to be able to identify a limited number of strains of Mycobacterium. In this study the method was improved by using more specific primers and was tested with 50 clinical isolates of M. tuberculosis and 65 clinical isolates of M. avium complex. Probes specific to the spacers of M. tuberculosis and M. avium were also tested. Both M. tuberculosis and M. avium could be reliably identified either by PCR-REA or by PCR-hybridization, with the results completely agreeing with those obtained by biochemical tests and with the Accuprobe, respectively. The method may therefore be useful as an alternative in-house method for identification of the bacteria.
| S-EPMC105132 | biostudies-literature
Project description:The 16S-23S spacer regions of two ribosomal operons (rrnA and rrnE) have been sequenced in seven representatives of the Salmonella enterica subspecies. Isolated nucleotide substitutions were found at the same sites as in Escherichia coli but the number of polymorphic sites was much larger, as could be expected for a more heterogeneous species. Still, as in E. coli, most of the variation found was due to insertions and/or deletions affecting blocks of nucleotides generally located at equivalent regions of the putative secondary structure for both species. Isolated polymorphic sites generated phylogenetic trees generally consistent with the subspecies structure and the accepted relationships among the subspecies. However, the sequences of rrnE put subspecies I closer to E. coli K-12 than to the other S. enterica subspecies. The distribution of polymorphisms affecting blocks of nucleotides was much more random, and the presence of equivalent sequences in distantly related subspecies, and even in E. coli, could reflect relatively frequent horizontal transfer. The smallest 16S-23S spacers in other genera of the family Enterobacteriaceae were also sequenced. As expected, the level of variation was much larger. Still, the phylogenetic tree inferred is consistent with those of 16S rRNA or housekeeping genes.
| S-EPMC107142 | biostudies-literature
Project description:Cultured isolates of the marine cyanobacteria Prochlorococcus and Synechococcus vary widely in their pigment compositions and growth responses to light and nutrients, yet show greater than 96% identity in their 16S ribosomal DNA (rDNA) sequences. In order to better define the genetic variation that accompanies their physiological diversity, sequences for the 16S-23S rDNA internal transcribed spacer (ITS) region were determined in 32 Prochlorococcus isolates and 25 Synechococcus isolates from around the globe. Each strain examined yielded one ITS sequence that contained two tRNA genes. Dramatic variations in the length and G+C content of the spacer were observed among the strains, particularly among Prochlorococcus strains. Secondary-structure models of the ITS were predicted in order to facilitate alignment of the sequences for phylogenetic analyses. The previously observed division of Prochlorococcus into two ecotypes (called high and low-B/A after their differences in chlorophyll content) were supported, as was the subdivision of the high-B/A ecotype into four genetically distinct clades. ITS-based phylogenies partitioned marine cluster A Synechococcus into six clades, three of which can be associated with a particular phenotype (motility, chromatic adaptation, and lack of phycourobilin). The pattern of sequence divergence within and between clades is suggestive of a mode of evolution driven by adaptive sweeps and implies that each clade represents an ecologically distinct population. Furthermore, many of the clades consist of strains isolated from disparate regions of the world's oceans, implying that they are geographically widely distributed. These results provide further evidence that natural populations of Prochlorococcus and Synechococcus consist of multiple coexisting ecotypes, genetically closely related but physiologically distinct, which may vary in relative abundance with changing environmental conditions.
| S-EPMC123739 | biostudies-literature
Project description:The current genetic strategies used to identify Tropheryma whippelii, the putative agent of Whipple's disease, are based on PCR-mediated amplification of a part of its 16S rRNA gene (16S rDNA). Because there is very little intraspecies variation in these molecules, they are not suitable as targets for epidemiologic investigations. However, the intergenic spacer region between the 16S and 23S rDNAs is usually much more variable and has repeatedly been used for epidemiologic purposes. We have therefore amplified the spacer region of T. whippelii directly from clinical specimens from nine independent Swiss patients with Whipple's disease by PCR with primers complementary to the 3' and 5' ends of the 16S and 23S rDNAs, respectively. The amplicons were directly sequenced and the sequences were compared to the T. whippelii reference sequence in GenBank/EMBL (accession no. X99636). Complete sequence homogeneity was found between the samples from our nine patients; the spacer sequence was also identical to the reference sequence. However, the sequences corresponding to the 3' and 5' ends of the 16S and the 23S rDNAs of T. whippelii, respectively, differed from the respective sequences in GenBank/EMBL. The same sequence found in our patients was then found in a sample from the German patient from which the published sequence had been derived. We conclude that the 16S-23S rDNA spacer region seems to be very conserved in T. whippelii and that the respective reference entry in public databases should be revised.
| S-EPMC84193 | biostudies-literature
Project description:A novel strategy for identification of Carnobacterium food isolates based on restriction fragment length polymorphism (RFLP) of PCR-amplified 16S-23S ribosomal intergenic spacer regions (ISRs) was developed. PCR amplification from all Carnobacterium strains studied always yielded three ISR amplicons, which were designated the small ISR (S-ISR), the medium ISR (M-ISR), and the large ISR (L-ISR). The lengths of these ISRs varied from one species to another. Carnobacterium divergens NCDO 2763(T) and C. mobile DSM 4849(T) generated one major S-ISR band (ca. 400 bp) and minor M-ISR and L-ISR bands (ca. 500 and ca. 600 bp, respectively). The ISRs amplified from C. gallinarum NCFB 2766(T) and C. piscicola NCDO 2762(T) were larger (S-ISR, ca. 600 bp; M-ISR, ca. 700 bp; and L-ISR, ca. 800 bp). The L-ISR contained two tDNAs coding for tRNA(Ile) and tRNA(Ala) genes. The M-ISR included one tRNA(Ala) gene, and the S-ISR did not contain a tDNA gene. The RFLP scheme devised involves estimation of variable PCR product sizes together with HinfI, TaqI, and HindIII restriction analysis. Forty-two isolates yielded four unique band patterns that correctly resolved these isolates into four Carnobacterium species. This method is very suitable for rapid, low-cost identification of a wide variety of Carnobacterium species without sequencing.
| S-EPMC129878 | biostudies-literature