Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: EC:2.7.7.49 (
reverse transcriptase
)
31,746
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Lippia javanica and Hoslundia opposita are aromatic herbs that occur all over Mozambique and are well known for their medicinal properties. A Phytochemical investigation of L. javanica led to the isolation of eight compounds, 4-ethyl-nonacosane (1), (E)-2(3)-tagetenone epoxide (2), myrcenone (3), piperitenone (4), apigenin (5), cirsimaritin (6), 6-methoxyluteolin 4'-methyl ether (7), 6-methoxyluteolin and 3',4',7-trimethyl ether (8). Three known compounds, 5,7-dimethoxy-6-methylflavone (9), hoslunddiol (10) and euscaphic acid (11) were isolated from H. opposita. This is the first report of compounds 1, 2, 5-8 from L. javanica and of compound (9) from H. opposita. The compounds were tested against
Mycobacterium
tuberculosis and HIV-1
reverse transcriptase
for bioactivity. It was found that compounds 2, 4 and 9 inhibited the HIV-1
reverse transcriptase
enzyme by 91, 53 and 52%, respectively, at 100 microg mL(-1). Of all the compounds tested against a drug-sensitive strain of M. tuberculosis, euscaphic acid (11) was found to exhibit a minimum inhibitory concentration of 50 microg mL(-1) against this strain.
...
PMID:Bioactive compounds from Lippia javanica and Hoslundia opposita. 1878 Feb 45
Mycobacterium
sp strain CH-2 was isolated from a manufactured gas plant contaminated with polycyclic aromatic hydrocarbons (PAHs) and was identified by analysis of 16S rDNA sequences. Strain CH-2 was capable of mineralizing 3- and 4- ring PAHs, including phenanthrene, pyrene, and fluoranthene. In addition, strain CH-2 could utilize phenanthrene, pyrene and a wide range of alkanes as a sole carbon and energy source. Primers based upon the sequences of the polycyclic aromatic hydrocarbon (PAH) dioxygenases nidAB (from
Mycobacterium
vanbaalenii strain PYR-1) and pdoA2B2 (from
Mycobacterium
sp. Strain 6PY1) were used as molecular probes to amplify the dioxygenases. Degenerate primers were used to amplify a portion of an alkane monooxygenase gene. Mineralization assays and
reverse transcriptase
-polymerase chain reaction (RT-PCR) analysis indicated that the alkane monooxygenase was constitutively expressed, while nidAB and pdoA2B2 were expressed only in the presence of PAHs. A genomic library of strain CH-2 was created and then screened for the presence of biodegradative operons using the amplified PAH dioxygenases. The pdolocus included a partial pdoF, as well as pdoA2, pdoB2, orf 72, and putative genes for a ferredoxin, an araC-type regulator, and a reductase. The nid locus included a partial nidC, as well as nidB, nidA, and a putative promoter. Primer extension analysis of the nidlocus located the transcriptional start site 68bp upstream of the nidB start codon. The putatively identified promoter region and a promoter fragment lacking the -10 region were amplified, and the products were cloned into pRW50. This plasmid carries the lac operon without a promoter. The plasmid containing the full length promoter expressed the lacZ reporter gene, while expression by the promoter fragment was equivalent to the expression of cells carrying pRW50.
...
PMID:Characterization of a pyrene-degrading Mycobacterium sp. strain CH-2. 1894 94
SigH regulates a transcriptional network that responds to heat and oxidative stress in mycobacteria. Seven sigH paralogs are reported to exist in the
Mycobacterium
smegmatis genome. A comprehensive real-time
reverse transcriptase
PCR analysis during different stages of growth and upon exposure to various stress conditions and antimycobacterial compounds showed differential expression of sigH paralogs during stationary phase and severalfold increases in the levels of transcription of sigH1, sigH4, sigH5, sigH6, and sigH7 under specific stress conditions.
...
PMID:Differential expression of sigH paralogs during growth and under different stress conditions in Mycobacterium smegmatis. 1921 86
Heat shock promoters of mycobacteria are strong promoters that become rapidly upregulated during macrophage infection and thus serve as valuable candidates for expressing foreign antigens in recombinant BCG vaccine. In the present study, a new heat shock promoter controlling the expression of the groESL1 operon was identified and characterized.
Mycobacterium
tuberculosis groESL1 operon codes for the immunodominant 10 kDa (Rv3418c, GroES/Cpn10/Hsp10) and 60 kDa (Rv3417c, GroEL1/Cpn60.1/Hsp60) heat shock proteins. The basal promoter region was 115 bp, while enhanced activity was seen only with a 277-bp fragment. No promoter element was seen in the groES-groEL1 intergenic region. This operon codes for a bicistronic mRNA transcript as determined by
reverse transcriptase
-PCR and Northern blot analysis. Primer extension analysis identified two transcriptional start sites (TSSs) TSS1 (-236) and TSS2 (-171), out of which one (TSS2) was heat inducible. The groE promoter was more active than the groEL2 promoter in
Mycobacterium
smegmatis. Further, it was found to be differentially regulated under stress conditions, while the groEL2 promoter was constitutive.
...
PMID:Mycobacterium tuberculosis groE promoter controls the expression of the bicistronic groESL1 operon and shows differential regulation under stress conditions. 1922 81
A simple, membrane-strip-based lateral-flow (LF) biosensor assay and a high-throughput microtiter plate assay have been combined with a
reverse transcriptase
polymerase chain reaction (RT-PCR) for the detection of a small number (ten) of viable
Mycobacterium
(M.) avium subsp. paratuberculosis (MAP) cells in fecal samples. The assays are based on the identification of the RNA of the IS900 element of MAP. For the assay, RNA was extracted from fecal samples spiked with a known quantity of (10(1) to 10(6)) MAP cells and amplified using RT-PCR and identified by the LF biosensor and the microtiter plate assay. While the LF biosensor assay requires only 30 min of assay time, the overall process took 10 h for the detection of 10 viable cells. The assays are based on an oligonucleotide sandwich hybridization assay format and use either a membrane flow through system with an immobilized DNA probe that hybridizes with the target sequence or a microtiter plate well. Signal amplification is provided when the target sequence hybridizes to a second DNA probe that has been coupled to liposomes encapsulating the dye, sulforhodamine B. The dye in the liposomes provides a signal that can be read visually, quantified with a hand-held reflectometer, or with a fluorescence reader. Specificity analysis of the assays revealed no cross reactivity with other mycobacteria, such as M. avium complex, M. ulcerans, M. marium, M. kansasii, M. abscessus, M. asiaticum, M. phlei, M. fortutitum, M. scrofalaceum, M. intracellular, M. smegmatis, and M. bovis. The overall assay for the detection of live MAP organisms is comparatively less expensive and quick, especially in comparison to standard MAP detection using a culture method requiring 6-8 weeks of incubation time, and is significantly less expensive than real-time PCR.
...
PMID:A biosensor assay for the detection of Mycobacterium avium subsp. paratuberculosis in fecal samples. 1925 22
Mycobacterium
leprae, the etiological agent of leprosy, is noncultivable on axenic media. Therefore, the viability of M. leprae for clinical or experimental applications is often unknown. To provide new tools for M. leprae viability determination, two quantitative
reverse transcriptase
PCR (RT-PCR) assays were developed and characterized. M. leprae sodA mRNA and 16S rRNA were used as RNA targets, and M. leprae repetitive element (RLEP) DNA was used to determine relative bacterial numbers in the same purified bacterial preparations or from crude biological specimens. Results demonstrated that both assays were good predictors of M. leprae viability during short-term experiments (48 h) involving rifampin (rifampicin) treatment in axenic medium, within rifampin-treated murine macrophages (MPhi), or within immune-activated MPhi. Moreover, these results strongly correlated those of other M. leprae viability assays, including radiorespirometry-based and Live/Dead BacLight viability assays. The 16S rRNA/RLEP assay consistently identified the presence of M. leprae in eight multibacillary leprosy patient biopsy specimens prior to multidrug therapy (MDT) and demonstrated a decline in viability during the course of MDT. In contrast, the sodA/RLEP assay was able to detect the presence of M. leprae in only 25% of pretreatment biopsy specimens. In conclusion, new tools for M. leprae viability determination were developed. The 16S rRNA/RLEP RT-PCR M. leprae viability assay should be useful both for short-term experimental purposes and for predicting M. leprae viability in biopsy specimens to monitor treatment efficacy, whereas the sodA/RLEP RT-PCR M. leprae viability assay should be limited to short-term experimental research purposes.
...
PMID:Molecular determination of Mycobacterium leprae viability by use of real-time PCR. 1943 37
We have previously reported that some pseudogenes are expressed in
Mycobacterium
leprae (M. leprae), the causative agent of leprosy, and that their expression levels alter upon infection of macrophages. We attempted to further examine the expression of pseudogene and non-coding genomic region in M. leprae, in this study. 19 Pseudogenes, 17 non-coding genomic regions, and 21 coding genes expression in M. leprae maintained in the footpads of the hypertensive nude rat (SHR/NCrj-rnu) were examined by
reverse transcriptase
polymerase chain reaction (RT-PCR). The expression of some of these pseudogenes, non-coding genomic regions and coding genes were also examined in M. leprae from skin smear specimens obtained from patients with lepromatous leprosy by RT-PCR. Transcripts from pseudogenes, non-coding genomic regions and coding genes examined in this study were clearly observed in M. leprae. The expression patterns of some of these transcripts vary greatly among different leprosy patients. These results indicate that some of pseudogenes and non-coding genomic regions are transcribed in M. leprae and analysis of RNA expression patterns including pseudogene and non-coding genomic region in M. leprae may be useful in understanding the pathological states of infected patients.
...
PMID:Detection of RNA expression from pseudogenes and non-coding genomic regions of Mycobacterium leprae. 1955 54
Ribulose 1,5-bisphosphate carboxylase/oxygenase (RubisCO) is the key enzyme of the Calvin reductive pentose phosphate cycle. Two sets of structural genes (cbbLS-1 and -2) for form I RubisCO have been previously identified in the
Mycobacterium
sp. strain JC1, which is able to grow on carbon monoxide (CO) or methanol as sole sources of carbon and energy. Northern blot and
reverse transcriptase
PCR showed that the cbbLS-1 and -2 genes are expressed in cells grown on either carbon monoxide (CO) or methanol, but not in cells grown in nutrient broth. A promoter assay revealed that the cbbLS-2 promoter has a higher activity than the cbbLS-1 promoter in both CO- and methanol-grown cells, and that the activities of both promoters were higher in CO-grown cells than in methanol-grown cells. A gel mobility shift assay and footprinting assays showed that CbbR expressed in Escherichia coli from a cbbR gene, which is located downstream of cbbLS-1 and transcribed in the same orientation as that of the cbbLS genes, specifically bound to the promoter regions of the cbbLS-1 and -2 genes containing inverted repeat sequence. A DNase I footprinting assay revealed that CbbR protected positions -59 to -3 and -119 to -78 of the cbbLS-1 and -2 promoters, respectively. Overexpression of CbbR induced the transcription of RubisCO genes in
Mycobacterium
sp. strain JC1 grown in nutrient broth. Our results suggest that the CbbR product from a single cbbR gene may positively regulate two cbbLS operons in the
Mycobacterium
sp. strain JC1 as is the case for Rhodobacter sphaeroides and Cupriavidus necator.
...
PMID:Expression and regulation of ribulose 1,5-bisphosphate carboxylase/oxygenase genes in Mycobacterium sp. strain JC1 DSM 3803. 1955 47
The degradation of fuel oxygenates [methyl tert-butyl ether (MTBE), ethyl tert-butyl ether (ETBE) and tert-amyl methyl ether (TAME)] by Rhodococcus ruber IFP 2001, Rhodococcus zopfii IFP 2005 and Gordonia sp. IFP 2009 (formerly
Mycobacterium
sp.) isolated from different environments was compared. Strains IFP 2001, IFP 2005 and IFP 2009 grew on ETBE due in part to the activity of a cytochrome P450, CYP249. All of these strains were able to degrade ETBE to tert-butyl alcohol and are harboring the CYP249 cytochrome P450. They were also able to degrade MTBE and TAME, but ETBE was degraded in all cases most efficiently, with degradation rates measured after growth on ETBE of 2.1, 3.5 and 1.6 mmol ETBE g(-1) dry weight h(-1) for strains IFP 2001, IFP 2005 and IFP 2009, respectively. The phylogenetic relationships between the different ethR (encoding the regulator) and ethB (encoding the cytochrome P450) genes were determined and showed high identity between different ethB genes (>99%). Only ETBE was able to induce the expression of ethB in strains IFP 2001 and IFP 2005 as measured by
reverse transcriptase
quantitative PCR. Our results are a first indication of the possible role played by the ethB gene in the ecology of ETBE degradation.
...
PMID:Cytochromes P450-mediated degradation of fuel oxygenates by environmental isolates. 2033 4
Johne's disease (JD) is a
mycobacterial infection
of the gut affecting ruminants and other species caused by
Mycobacterium
avium subspecies paratuberculosis (MAP). The role of toll-like receptors (TLR) in the pathogenesis of JD has been previously identified at the level of gene expression. Gene expression studies using
reverse transcriptase
(RT)-PCR are widely used and powerful, but the results obtained from such studies are dependent on the specificity of the assay. Here we describe an assay designed to detect ovine TLR6 in blood and tissues from sheep. Discrimination between TLR1 and TLR6 at the level of gene expression was challenging due to extensive tracts of homology and identity within the two sequences. Both TLR1 and 6 can form heterodimers with TLR2 in order to bind the ligands of microbial pathogens. The expression of TLR6 was increased in the ileum and jejunum of sheep infected with MAP, with a trend towards TLR6 upregulation in peripheral blood cells in response to exposure to MAP. A likely role for TLR6/TLR2 heterodimers in the pathogenesis of JD was identified. TLR6 may be a potential marker of exposure and could aid in the development of a gene signature for sheep resistant to MAP infection.
...
PMID:Toll-like receptor (TLR)6 and TLR1 differentiation in gene expression studies of Johne's disease. 2043 22
<< Previous
1
2
3
4
5
6
7
8
9
10
Next >>