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Microorganisms Jun 2024The Esx-1 family proteins of the Type VII secretion systems of and have been assessed and are frequently used as candidates for tuberculosis (TB) diagnosis in both...
The Presence of and and Other Gene Orthologs of the RD 1 Region in Non-Tuberculous Mycobacteria, Mycolicibacteria, Mycobacteroides and Mycolicibacter as Possible Impediments for the Diagnosis of (Animal) Tuberculosis.
The Esx-1 family proteins of the Type VII secretion systems of and have been assessed and are frequently used as candidates for tuberculosis (TB) diagnosis in both humans and animals. The presence of ESAT-6 and CFP 10 proteins, which are the most immunogenic proteins of the Esx-1 system and have been widely investigated for the immunodiagnosis of tuberculosis, in some and in , poses limitations for their use in specific diagnoses of TB. As such, to improve the specificity of the ESAT-6/CFP 10-based cell-mediated immunity (CMI) assays, other proteins encoded by genes within and outside the RD 1 region of the esx-1 locus have been evaluated as candidate antigens for CMI, as well as to investigate humoral responses in combination with ESAT-6 and or CFP 10, with varying specificity and sensitivity results. Hence, in this study, we evaluated various non-tuberculous mycobacteria (NTM), , and species genomes available on the NCBI database for the presence and composition of the RD1 region of the esx-1 locus. In addition, we also assayed by polymerase chain reaction (PCR) and sequencing of available in our culture collection for the presence and sequence diversity of and genes encoding ESAT-6 and CFP 10, respectively. Whole genome sequence (WGS) data analysis revealed the presence of RD 1 gene orthologs in 70 of the over 100 published genomes of pathogenic and non- pathogenic other than tuberculosis. Among species evaluated from our culture collection, in addition to earlier reports of the presence of and in certain , , and sp. N845T were also found to harbour orthologs of both genes. Orthologs of only were detected in , and , whereas in , and , only orthologs were detected. A phylogenetic analysis based on and sequences separated slow-growing from rapidly growing bacteria. These findings strengthen previous suggestions that and may be encoded in the majority of . The role of the Esx-1 system in both pathogenic and non-pathogenic needs further investigation, as these species may pose limitations to immunological assays for TB.
PubMed: 38930534
DOI: 10.3390/microorganisms12061151 -
Biomolecules Jun 2024Incidences of drug-resistant tuberculosis have become common and are rising at an alarming rate. Aminoacyl t-RNA synthetase has been validated as a newer target against...
Incidences of drug-resistant tuberculosis have become common and are rising at an alarming rate. Aminoacyl t-RNA synthetase has been validated as a newer target against . Leucyl t-RNA synthetase (LeuRS) is ubiquitously found in all organisms and regulates transcription, protein synthesis, mitochondrial RNA cleavage, and proofreading of matured t-RNA. Leucyl t-RNA synthetase promotes growth and development and is the key enzyme needed for biofilm formation in Mycobacterium. Inhibition of this enzyme could restrict the growth and development of the mycobacterial population. A database consisting of 2734 drug-like molecules was screened against leucyl t-RNA synthetase enzymes through virtual screening. Based on the docking scores and MMGBSA energy values, the top three compounds were selected for molecular dynamics simulation. The druggable nature of the top three hits was confirmed by predicting their pharmacokinetic parameters. The top three hits-compounds (ZINC000001543916), (ZINC000001554197), and (ZINC000008214483)-were evaluated for their binding affinity toward leucyl t-RNA synthetase by an isothermal titration calorimetry study. The inhibitory activity of these compounds was tested against antimycobacterial activity, biofilm formation, and LeuRS gene expression potential. Compound (Macimorelin) was found to be the most potent molecule, with better antimycobacterial activity, enzyme binding affinity, and significant inhibition of biofilm formation, as well as inhibition of the LeuRS gene expression. Compound , the top hit compound, has the potential to be used as a lead to develop successful leucyl t-RNA synthetase inhibitors.
Topics: Mycobacterium tuberculosis; Ligands; Antitubercular Agents; Leucine-tRNA Ligase; Molecular Docking Simulation; Enzyme Inhibitors; Calorimetry; Molecular Dynamics Simulation; Tuberculosis; Computer Simulation; Protein Binding; Humans
PubMed: 38927114
DOI: 10.3390/biom14060711 -
Scientific Reports Jun 2024Dental calculus is a microbial biofilm that contains biomolecules from oral commensals and pathogens, including those potentially related to cause of death (CoD). To...
Dental calculus is a microbial biofilm that contains biomolecules from oral commensals and pathogens, including those potentially related to cause of death (CoD). To assess the utility of calculus as a diagnostically informative substrate, in conjunction with paleopathological analysis, calculus samples from 39 individuals in the Smithsonian Institution's Robert J. Terry Collection with CoDs of either syphilis or tuberculosis were assessed via shotgun metagenomic sequencing for the presence of Treponema pallidum subsp. pallidum and Mycobacterium tuberculosis complex (MTBC) DNA. Paleopathological analysis revealed that frequencies of skeletal lesions associated with these diseases were partially inconsistent with diagnostic criteria. Although recovery of T. p. pallidum DNA from individuals with a syphilis CoD was elusive, MTBC DNA was identified in at least one individual with a tuberculosis CoD. The authenticity of MTBC DNA was confirmed using targeted quantitative PCR assays, MTBC genome enrichment, and in silico bioinformatic analyses; however, the lineage of the MTBC strain present could not be determined. Overall, our study highlights the utility of dental calculus for molecular detection of tuberculosis in the archaeological record and underscores the effect of museum preparation techniques and extensive handling on pathogen DNA preservation in skeletal collections.
Topics: Dental Calculus; Humans; Metagenomics; Paleopathology; Tuberculosis; Mycobacterium tuberculosis; DNA, Bacterial; Male; Treponema pallidum; Syphilis; Female; Adult; Metagenome; Middle Aged
PubMed: 38926415
DOI: 10.1038/s41598-024-64818-7 -
Microbial Biotechnology Jun 2024Ethylene and ethylene oxide are widely used in the chemical industry, and ethylene is also important for its role in fruit ripening. Better sensing systems would assist...
Ethylene and ethylene oxide are widely used in the chemical industry, and ethylene is also important for its role in fruit ripening. Better sensing systems would assist risk management of these chemicals. Here, we characterise the ethylene regulatory system in Mycobacterium strain NBB4 and use these genetic parts to create a biosensor. The regulatory genes etnR1 and etnR2 and cognate promoter P were combined with a fluorescent reporter gene (fuGFP) in a Mycobacterium shuttle vector to create plasmid pUS301-EtnR12P. Cultures of M. smegmatis mc-155(pUS301-EtnR12P) gave a fluorescent signal in response to ethylene oxide with a detection limit of 0.2 μM (9 ppb). By combining the epoxide biosensor cells with another culture expressing the ethylene monooxygenase, the system was converted into an ethylene biosensor. The co-culture was capable of detecting ethylene emission from banana fruit. These are the first examples of whole-cell biosensors for epoxides or aliphatic alkenes. This work also resolves long-standing questions concerning the regulation of ethylene catabolism in bacteria.
Topics: Biosensing Techniques; Ethylenes; Ethylene Oxide; Mycobacterium; Musa; Genes, Reporter; Plasmids
PubMed: 38925606
DOI: 10.1111/1751-7915.14511 -
ELife Jun 2024During tuberculosis (TB), migration of dendritic cells (DCs) from the site of infection to the draining lymph nodes is known to be impaired, hindering the rapid...
During tuberculosis (TB), migration of dendritic cells (DCs) from the site of infection to the draining lymph nodes is known to be impaired, hindering the rapid development of protective T-cell-mediated immunity. However, the mechanisms involved in the delayed migration of DCs during TB are still poorly defined. Here, we found that infection of DCs with (Mtb) triggers HIF1A-mediated aerobic glycolysis in a TLR2-dependent manner, and that this metabolic profile is essential for DC migration. In particular, the lactate dehydrogenase inhibitor oxamate and the HIF1A inhibitor PX-478 abrogated Mtb-induced DC migration in vitro to the lymphoid tissue-specific chemokine CCL21, and in vivo to lymph nodes in mice. Strikingly, we found that although monocytes from TB patients are inherently biased toward glycolysis metabolism, they differentiate into poorly glycolytic and poorly migratory DCs compared with healthy subjects. Taken together, these data suggest that because of their preexisting glycolytic state, circulating monocytes from TB patients are refractory to differentiation into migratory DCs, which may explain the delayed migration of these cells during the disease and opens avenues for host-directed therapies for TB.
Topics: Dendritic Cells; Glycolysis; Monocytes; Humans; Hypoxia-Inducible Factor 1, alpha Subunit; Mycobacterium tuberculosis; Cell Movement; Animals; Tuberculosis; Mice; Toll-Like Receptor 2; Mice, Inbred C57BL; Female
PubMed: 38922679
DOI: 10.7554/eLife.89319 -
Marine Drugs Jun 2024A new dimeric C-glycoside polyketide chrysomycin F (), along with four new monomeric compounds, chrysomycins G (), H (), I (), J (), as well as three known analogues,...
A new dimeric C-glycoside polyketide chrysomycin F (), along with four new monomeric compounds, chrysomycins G (), H (), I (), J (), as well as three known analogues, chrysomycins A (), B (), and C (), were isolated and characterised from a strain of sp. obtained from a sediment sample collected from the South China Sea. Their structures were determined by detailed spectroscopic analysis. Chrysomycin F contains two diastereomers, whose structures were further elucidated by a biomimetic [2 + 2] photodimerisation of chrysomycin A. Chrysomycins B and C showed potent anti-tuberculosis activity against both wild-type and a number of clinically isolated MDR strains.
Topics: Streptomyces; Mycobacterium tuberculosis; Antitubercular Agents; Polyketides; Microbial Sensitivity Tests; Glycosides; China; Molecular Structure; Anthraquinones
PubMed: 38921570
DOI: 10.3390/md22060259 -
Marine Drugs May 2024Tuberculosis, a persistent illness caused by , remains a significant global public health challenge. The widespread use of anti-tuberculosis drugs has resulted in the...
Tuberculosis, a persistent illness caused by , remains a significant global public health challenge. The widespread use of anti-tuberculosis drugs has resulted in the emergence of drug-resistant strains, which complicates treatment efforts. Addressing this issue is crucial and hinges on the development of new drugs that can effectively target the disease. This involves identifying novel therapeutic targets that can disrupt the bacterium's survival mechanisms in various environments such as granulomas and lesions. Citrate lyase, essential for the survival of species at lesion sites and in granulomatous conditions, is a potential target for the treatment of tuberculosis. This manuscript aimed to construct an efficient enzyme inhibitor screening platform using ultra-high performance liquid chromatography-quadrupole-time-of-flight mass spectrometry (UHPLC-QTOF MS). This system can accurately identify compounds with enzyme inhibitory activity from a library of marine terpenoids and phenolic compounds. Utilizing the screened herbal enzyme inhibitors as a starting point, we analyzed their chemical structures and skillfully built a library of marine compounds based on these structures. The results showed that all of the tested compounds from the phenolics library inhibited citrate lyase by more than 50%, and a significant portion of terpenoids also demonstrated inhibition, with these active terpenoids comprising over half of the terpenoids tested. The study underscores the potential of marine-derived phenolic and terpenoid compounds as potent inhibitors of citrate lyase, indicating a promising direction for future investigations in treating tuberculosis and associated disorders.
Topics: Tandem Mass Spectrometry; Enzyme Inhibitors; Antitubercular Agents; Mycobacterium tuberculosis; Chromatography, High Pressure Liquid; ATP Citrate (pro-S)-Lyase; Aquatic Organisms; Terpenes; Humans; Phenols; Chromatography, Liquid
PubMed: 38921556
DOI: 10.3390/md22060245 -
Cells Jun 2024causes 6.4 million cases of tuberculosis and claims 1.6 million lives annually. Mycobacterial adhesion, invasion of host cells, and subsequent intracellular survival...
causes 6.4 million cases of tuberculosis and claims 1.6 million lives annually. Mycobacterial adhesion, invasion of host cells, and subsequent intracellular survival are crucial for the infection and dissemination process, yet the cellular mechanisms underlying these phenomena remain poorly understood. This study created a (BCG) transposon library using a MycomarT7 phage carrying a Himar1 Mariner transposon to identify genes related to mycobacteria adhesion and invasion. Using adhesion and invasion model screening, we found that the mutant strain B2909 lacked adhesion and invasion abilities because of an inactive gene, which encodes a fatty-acyl CoA ligase, although the specific function of this gene remains unclear. To investigate the role of FadD18, we constructed a complementary strain and observed that expression enhanced the colony size and promoted the formation of a stronger cord-like structure; FadD18 expression also inhibited BCG growth and reduced BCG intracellular survival in macrophages. Furthermore, FadD18 expression elevated levels of the proinflammatory cytokines IL-6, IL-1β, and TNF-α in infected macrophages by stimulating the NF-κB and MAPK signaling pathways. Overall, the FadD18 plays a key role in the adhesion and invasion abilities of mycobacteria while modulating the intracellular survival of BCG by influencing the production of proinflammatory cytokines.
Topics: Mycobacterium tuberculosis; Cytokines; Macrophages; Mycobacterium bovis; Mice; Bacterial Proteins; Animals; Humans; NF-kappa B; Microbial Viability; Bacterial Adhesion
PubMed: 38920649
DOI: 10.3390/cells13121019 -
BMC Infectious Diseases Jun 2024Proper diagnosis of tuberculosis (TB) lymphadenitis is critical for its treatment and prevention. Fine needle aspirate cytology (FNAC) is the mainstay method for the...
INTRODUCTION
Proper diagnosis of tuberculosis (TB) lymphadenitis is critical for its treatment and prevention. Fine needle aspirate cytology (FNAC) is the mainstay method for the diagnosis of TB lymphadenitis in Ethiopia; however, the performance of FNAC has not been evaluated in the Eastern Region of Ethiopia. This study aimed to evaluate the performance of FNAC and Ziehl-Neelsen (ZN) staining compared with that of GeneXpert for the diagnosis of TB lymphadenitis.
METHODS
Fine needle aspiration (FNA) specimens collected from 291 patients suspected of having TB lymphadenitis were examined using FNAC, ZN, and GeneXpert to diagnose TB lymphadenitis. Gene-Xpert was considered the reference standard method for comparison. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and kappa coefficient were determined using SPSS version 25.
RESULTS
The sensitivity, specificity, PPV, and NPV of ZN for diagnosing TB lymphadenitis were 73.2%, 97.4%, 96.2%, and 80.1% respectively. There was poor agreement between ZN and GeneXpert (Kappa=-0.253). The sensitivity, specificity, PPV, and NPV of FNAC were 83.3%, 94.8%, 93.5%, and 86.3% respectively. There was moderate agreement between the FNAC and GeneXpert (Kappa = 0.785).
CONCLUSION
The fine needle aspiration cytology (FNAC) is a more sensitive test for the diagnosis of TB lymphadenitis than ZN. The FNAC showed a moderate agreement with the GeneXpert assay. This study recommends the FNA GeneXpert MTB/RIF test in preference to FNAC for the diagnosis of TB lymphadenitis to avoid a missed diagnosis of smear-negative TB lymphadenitis.
Topics: Humans; Biopsy, Fine-Needle; Tuberculosis, Lymph Node; Female; Male; Adult; Sensitivity and Specificity; Young Adult; Middle Aged; Staining and Labeling; Adolescent; Ethiopia; Mycobacterium tuberculosis; Child; Aged; Cytology
PubMed: 38918686
DOI: 10.1186/s12879-024-09554-z -
Scientific Reports Jun 2024The emergence of drug-resistant Mycobacterium tuberculosis strains is a threat to global health necessitating the discovery of novel chemotherapeutic agents. Natural...
The emergence of drug-resistant Mycobacterium tuberculosis strains is a threat to global health necessitating the discovery of novel chemotherapeutic agents. Natural products drug discovery, which previously led to the discovery of rifamycins, is a valuable approach in this endeavor. Against this backdrop, we set out to investigate the in vitro antimycobacterial properties of medicinal plants from Ghana and South Africa, evaluating 36 extracts and their 252 corresponding solid phase extraction (SPE) generated fractions primarily against the non-pathogenic Mycobacterium smegmatis and Mycobacterium aurum species. The most potent fraction was further evaluated in vitro against infectious M. tuberculosis strain. Crinum asiaticum (bulb) (Amaryllidaceae) emerged as the most potent plant species with specific fractions showing exceptional, near equipotent activity against the non-pathogenic Mycobacterium species (0.39 µg/ml ≤ MIC ≤ 25 µg/ml) with one fraction being moderately active (MIC = 32.6 µg/ml) against M. tuberculosis. Metabolomic analysis led to the identification of eight compounds predicted to be active against M. smegmatis and M. aurum. In conclusion, from our comprehensive study, we generated data which provided an insight into the antimycobacterial properties of Ghanaian and South African plants. Future work will be focused on the isolation and evaluation of the compounds predicted to be active.
Topics: Plants, Medicinal; Microbial Sensitivity Tests; South Africa; Plant Extracts; Ghana; Mycobacterium tuberculosis; Antitubercular Agents; Mycobacterium; Mycobacterium smegmatis; Humans; Anti-Bacterial Agents
PubMed: 38918410
DOI: 10.1038/s41598-024-65369-7