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BMC Microbiology Feb 2022Mycobacterium tuberculosis population in Russia is dominated by the notorious Beijing genotype whose major variants are characterized by contrasting resistance and...
BACKGROUND
Mycobacterium tuberculosis population in Russia is dominated by the notorious Beijing genotype whose major variants are characterized by contrasting resistance and virulence properties. Here we studied how these strain features could impact the progression of pulmonary tuberculosis (TB) concerning clinical manifestation and lethal outcome.
RESULTS
The study sample included 548 M. tuberculosis isolates from 548 patients with newly diagnosed pulmonary TB in Omsk, West Siberia, Russia. Strains were subjected to drug susceptibility testing and genotyping to detect lineages, sublineages, and subtypes (within Beijing genotype). The Beijing genotype was detected in 370 (67.5%) of the studied strains. The strongest association with multidrug resistance (MDR) was found for epidemic cluster Beijing B0/W148 (modern sublineage) and two recently discovered MDR clusters 1071-32 and 14717-15 of the ancient Beijing sublineage. The group of patients infected with hypervirulent and highly lethal (in a mouse model) Beijing 14717-15 showed the highest rate of lethal outcome (58.3%) compared to Beijing B0/W148 (31.4%; P = 0.06), Beijing Central Asian/Russian (29.7%, P = 0.037), and non-Beijing (15.2%, P = 0.001). The 14717-15 cluster mostly included isolates from patients with infiltrative but not with fibrous-cavernous and disseminated TB. In contrast, a group infected with low virulent 1071-32-cluster had the highest rate of fibrous-cavernous TB, possibly reflecting the capacity of these strains for prolonged survival and chronicity of the TB process.
CONCLUSIONS
The group of patients infected with hypervirulent and highly lethal in murine model 14717-15 cluster had the highest proportion of the lethal outcome (58.3%) compared to the groups infected with Beijing B0/W148 (31.4%) and non-Beijing (15.2%) isolates. This study carried out in the TB high-burden area highlights that not only drug resistance but also strain virulence should be considered in the implementation of personalized TB treatment.
Topics: Adolescent; Adult; Antitubercular Agents; DNA, Bacterial; Drug Resistance, Multiple, Bacterial; Female; Genetic Variation; Genotype; Humans; Male; Middle Aged; Mycobacterium tuberculosis; Russia; Tuberculosis, Multidrug-Resistant; Tuberculosis, Pulmonary; Virulence; Young Adult
PubMed: 35135478
DOI: 10.1186/s12866-022-02461-w -
Emerging Microbes & Infections Dec 2021strains of the early ancient sublineage of the Beijing genotype are mostly drug susceptible and mainly circulate in East Asia. We have recently discovered two clusters...
strains of the early ancient sublineage of the Beijing genotype are mostly drug susceptible and mainly circulate in East Asia. We have recently discovered two clusters of this sublineage emerging in the Asian part of Russia (VNTR-defined 1071-32 and 14717-15 types) and, to our surprise, both were strongly MDR/XDR-associated. Here, we evaluated their pathogenic features. The clinical isolates and reference laboratory strain H37Rv were investigated in the C57BL/6 mouse model to assess their virulence and lethality properties. The BACTEC MGIT 960 system was used to study the in vitro growth characteristics. In the murine model, strains 396 (14717-15-cluster, from Buryatia, Far East) and 6691 (1071-32-cluster, from Omsk, Siberia) demonstrated contrasting properties. The 396-infected group had significantly higher mortality, more weight loss, higher bacterial burden, and more severe lung pathology. Furthermore, compared to the previously published data on other Russian epidemic Beijing strains (B0/W148, CAO, Central Asian Russian), strain 396 demonstrated the highest mortality. Under the in vitro growth experiment, cluster 14717-15 isolates had significantly shorter lag-phase. To conclude, low-virulent MDR strain 6691 belongs to the Beijing 1071-32-cluster widespread across FSU countries but at low prevalence. This corresponds to common expectation that multiple drug resistance mutations reduce fitness and virulence. In contrast, highly lethal and hypervirulent MDR strain 396 represents an intriguing Beijing 14717-15 cluster predominant only in Buryatia, Far East (16%), sporadically found beyond it, but not forming clusters of transmission. Further in-depth study of this most virulent Russian Beijing cluster is warranted.
Topics: Animals; Antitubercular Agents; Beijing; DNA, Bacterial; Disease Models, Animal; Drug Resistance, Multiple, Bacterial; Epidemics; Genotype; Male; Mice; Mice, Inbred C57BL; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Russia; Tuberculosis, Multidrug-Resistant; Virulence
PubMed: 34380361
DOI: 10.1080/22221751.2021.1967704 -
Annals of Clinical Microbiology and... May 2024Pretomanid is a key component of new regimens for the treatment of drug-resistant tuberculosis (TB) which are being rolled out globally. However, there is limited...
BACKGROUND
Pretomanid is a key component of new regimens for the treatment of drug-resistant tuberculosis (TB) which are being rolled out globally. However, there is limited information on the prevalence of pre-existing resistance to the drug.
METHODS
To investigate pretomanid resistance rates in China and its underlying genetic basis, as well as to generate additional minimum inhibitory concentration (MIC) data for epidemiological cutoff (ECOFF)/breakpoint setting, we performed MIC determinations in the Mycobacterial Growth Indicator Tube™ (MGIT) system, followed by WGS analysis, on 475 Mycobacterium tuberculosis (MTB) isolated from Chinese TB patients between 2013 and 2020.
RESULTS
We observed a pretomanid MIC distribution with a 99% ECOFF equal to 0.5 mg/L. Of the 15 isolates with MIC values > 0.5 mg/L, one (MIC = 1 mg/L) was identified as MTB lineage 1 (L1), a genotype previously reported to be intrinsically less susceptible to pretomanid, two were borderline resistant (MIC = 2-4 mg/L) and the remaining 12 isolates were highly resistant (MIC ≥ 16 mg/L) to the drug. Five resistant isolates did not harbor mutations in the known pretomanid resistant genes.
CONCLUSIONS
Our results further support a breakpoint of 0.5 mg/L for a non-L1 MTB population, which is characteristic of China. Further, our data point to an unexpected high (14/475, 3%) pre-existing pretomanid resistance rate in the country, as well as to the existence of yet-to-be-discovered pretomanid resistance genes.
Topics: Mycobacterium tuberculosis; China; Humans; Microbial Sensitivity Tests; Antitubercular Agents; Tuberculosis, Multidrug-Resistant; Prevalence; Nitroimidazoles; Genotype; Mutation; Whole Genome Sequencing
PubMed: 38702782
DOI: 10.1186/s12941-024-00697-0 -
Science Advances Dec 2023Iron-sulfur (Fe-S) biogenesis requires multiprotein assembly systems, SUF and ISC, in most prokaryotes. () encodes a complete SUF system, the depletion of which was...
Iron-sulfur (Fe-S) biogenesis requires multiprotein assembly systems, SUF and ISC, in most prokaryotes. () encodes a complete SUF system, the depletion of which was bactericidal. The ISC operon is truncated to a single gene (cysteine desulfurase), whose function remains uncertain. Here, we show that Δ is bioenergetically deficient and hypersensitive to oxidative stress, antibiotics, and hypoxia. Δ resisted killing by nitric oxide (NO). RNA sequencing indicates that IscS is important for expressing regulons of DosR and Fe-S-containing transcription factors, WhiB3 and SufR. Unlike wild-type , Δ could not enter a stable persistent state, continued replicating in mice, and showed hypervirulence. The operon was overexpressed in Δ during infection in a NO-dependent manner. Suppressing expression in Δ either by CRISPR interference or upon infection in inducible NO-deficient mice arrests hypervirulence. Together, redesigned the ISC system to "fine-tune" the expression of SUF machinery for establishing persistence without causing detrimental disease in the host.
Topics: Animals; Mice; Energy Metabolism; Escherichia coli; Mycobacterium tuberculosis; Virulence
PubMed: 38091389
DOI: 10.1126/sciadv.adh2858 -
Tuberculosis (Edinburgh, Scotland) Jan 2021Although treatable with antibiotics, tuberculosis is a leading cause of death. Mycobacterium tuberculosis antibiotic resistance is becoming increasingly common and...
Although treatable with antibiotics, tuberculosis is a leading cause of death. Mycobacterium tuberculosis antibiotic resistance is becoming increasingly common and disease control is challenging. Conventional drug susceptibility testing takes weeks to produce results, and treatment is often initiated empirically. Therefore, new methods to determine drug susceptibility profiles are urgent. Here, we used mass-spectrometry-based metabolomics to characterize the metabolic landscape of drug-susceptible (DS), multidrug-resistant (MDR) and extensively drug-resistant (XDR) M. tuberculosis. Direct infusion mass spectrometry data showed that DS, MDR, and XDR strains have distinct metabolic profiles, which can be used to predict drug susceptibility and resistance. This was later confirmed by Ultra-High-Performance Liquid Chromatography and High-Resolution Mass Spectrometry, where we found that levels of ions presumptively identified as isoleucine, proline, hercynine, betaine, and pantothenic acid varied significantly between strains with different drug susceptibility profiles. We then confirmed the identification of proline and isoleucine and determined their absolute concentrations in bacterial extracts, and found significantly higher levels of these amino acids in DS strains, as compared to drug-resistant strains (combined MDR and XDR strains). Our results advance the current understanding of the effect of drug resistance on bacterial metabolism and open avenues for the detection of drug resistance biomarkers.
Topics: Antitubercular Agents; Extensively Drug-Resistant Tuberculosis; Humans; Metabolome; Metabolomics; Microbial Sensitivity Tests; Mycobacterium tuberculosis
PubMed: 33370646
DOI: 10.1016/j.tube.2020.102043 -
PloS One 2020Cigarette smoking and tuberculosis are a significant cause of death worldwide. Several epidemiological studies have demonstrated cigarette smoking is a risk factor for...
Cigarette smoking and tuberculosis are a significant cause of death worldwide. Several epidemiological studies have demonstrated cigarette smoking is a risk factor for tuberculosis. Electronic cigarettes have recently appeared as a healthier alternative to conventional smoking, although their impact in tuberculosis is not well understood. The aim of this study was to explore the effect of electronic cigarettes in phagocytosis of Mycobacterium tuberculosis and cytokines production. In vitro infection was carried out by exposing THP-1 macrophages to four electronic vapor extracts and the intracellular burden of M. tuberculosis was determined. The percentage of infection was evaluated by confocal microscopy and the cytokine production by Luminex. A reduction of intracellular M. tuberculosis burden in THP-1 macrophages was found after its exposure to electronic vapor extract; the same trend was observed by confocal microscopy when Mycobacterium bovis BCG-GFP strain was used. Electronic cigarettes stimulate a pro-inflammatory cytokine response. We conclude that electronic cigarettes impair the phagocytic function and the cytokine response to M. tuberculosis.
Topics: Cell Survival; Cytokines; Electronic Nicotine Delivery Systems; Humans; Immunity, Innate; Inflammation Mediators; Macrophages; Mycobacterium tuberculosis; Phagocytosis; Smoke; Smoking; THP-1 Cells
PubMed: 32040536
DOI: 10.1371/journal.pone.0228919 -
PLoS Neglected Tropical Diseases May 2020Mycobacterium tuberculosis complex (MTBC), the causative agent of tuberculosis (TB), is composed of eight subspecies. TB in West Africa, in contrast to other... (Comparative Study)
Comparative Study
BACKGROUND
Mycobacterium tuberculosis complex (MTBC), the causative agent of tuberculosis (TB), is composed of eight subspecies. TB in West Africa, in contrast to other geographical regions, is caused by Mycobacterium africanum (MAF) in addition to M. tuberculosis (MTB), with both infections presenting similar symptoms. Nevertheless, MAF is considered to be hypovirulent in comparison with MTB and less likely to progress to active disease. In this study, we asked whether MAF and MTB infected patients possess distinct intestinal microbiomes and characterized how these microbiota communities are affected by anti-tuberculosis therapy (ATT). Additionally, we assessed if the changes in microbiota composition following infection correlate with pathogen induced alterations in host blood-gene expression.
METHODS
A longitudinal, clinical study of MAF infected, MTB infected patients assessed at diagnosis and two months after start of ATT, and healthy, endemic controls was conducted to compare compositions of the fecal microbiome as determined by 16S rRNA sequencing. A blood transcriptome analysis was also performed on a subset of subjects in each group by microarray and the results cross-compared with the same individual's microbiota composition.
FINDINGS
MAF participants have distinct microbiomes compared with MTB patients, displaying decreased diversity and increases in Enterobacteriaceae with respect to healthy participants not observed in the latter patient group. Interestingly, this observed elevation in Enterobacteriaceae positively correlated with enhanced inflammatory gene expression in peripheral blood and was reversed after initiation of ATT.
INTERPRETATION
Our findings indicate that MAF and MTB have distinct associations with the gut microbiome that may be reflective of the differential susceptibility of West Africans to these two co-endemic infections either as biomarkers or as a contributing determinant.
Topics: Adult; Aged; Bacteria; Cohort Studies; Feces; Female; Gastrointestinal Microbiome; Humans; Longitudinal Studies; Male; Middle Aged; Mycobacterium; Mycobacterium tuberculosis; Tuberculosis; Young Adult
PubMed: 32401750
DOI: 10.1371/journal.pntd.0008230 -
International Journal of Biological... Dec 2023Feast/famine regulatory proteins (FFRPs) are multifunctional regulators. We show that Mtb Rv2324 is important for growth, survival, and countering DNA damage in...
Feast/famine regulatory proteins (FFRPs) are multifunctional regulators. We show that Mtb Rv2324 is important for growth, survival, and countering DNA damage in Mycobacterium tuberculosis (Mtb). DNA-relaxation activity against linear and supercoiled substrates suggest its involvement in transcription activation, while its high affinity for recombination, replication and repair substrates suggest a role there too. Small-Angle-X-ray scattering supports the adoption of an 'open' quaternary association in response to amino-acid binding. Size-exclusion-chromatography and glutaraldehyde cross-linking identify the adoption of diverse oligomers modulated by amino-acid binding, and DNA interactions. We tested G52A, G101T and D104A mutants which correspond to highly conserved residues, distal to the DNA-binding site, and are important for amino acids binding. G101T exhibits increased DNA affinity, while G52A and D104A exhibit weak DNA-binding thereby suggesting that they mediate effector-binding, and DNA binding activities. Gain and loss-of-function studies show that Rv2324 overexpression promotes growth-rate, while its knock-down leads to retarded growth. Rv2324 down-regulation lowers Mtb survival inside resting and IFN-ϒ-activated macrophages. Rv2324 protects the pathogen from DNA damage, as evidenced by the reduction in the knockdown strain's survival following treatment with H2O2 and UV light. Overall, we show that Rv2324 plays a crucial role in regulating survival and growth of Mtb.
Topics: Mycobacterium tuberculosis; Hydrogen Peroxide; Transcription Factors; DNA; DNA Replication; Bacterial Proteins
PubMed: 37634786
DOI: 10.1016/j.ijbiomac.2023.126459 -
Infectious Disease Clinics of North... Dec 2020Multidrug-resistant Mycobacterium tuberculosis remains a major public health threat; its management poses a significant economic burden. Treatment requires a... (Review)
Review
Multidrug-resistant Mycobacterium tuberculosis remains a major public health threat; its management poses a significant economic burden. Treatment requires a programmatic approach with access to laboratory services, second-line medications, and adequate clinical resources. In recent years, we have seen rapid developments in diagnostic techniques with whole genome sequencing-based drug susceptibility prediction now in reach, an array of new drugs that transform treatment regimens to purely oral formulations, and a steady stream of multinational trials that inform us about most efficient combinations. Our hope is that the current momentum keeps the ambitious goal to end tuberculosis in 2030 in reach.
Topics: Anti-Bacterial Agents; Antitubercular Agents; Early Diagnosis; Genome, Bacterial; Humans; Microbial Sensitivity Tests; Mutation; Mycobacterium tuberculosis; Tuberculosis, Multidrug-Resistant; Whole Genome Sequencing
PubMed: 33011048
DOI: 10.1016/j.idc.2020.06.001 -
Frontiers in Immunology 2020Autophagy, an intracellular catabolic pathway featuring lysosomal degradation, is a central component of the host immune defense against various infections including... (Review)
Review
Autophagy, an intracellular catabolic pathway featuring lysosomal degradation, is a central component of the host immune defense against various infections including (Mtb), the pathogen that causes tuberculosis. Mtb can evade the autophagic defense and drive immunometabolic remodeling of host phagocytes. Co-regulation of the autophagic and metabolic pathways may play a pivotal role in shaping the innate immune defense and inflammation during Mtb infection. Two principal metabolic sensors, AMP-activated protein kinase (AMPK) and mammalian target of rapamycin (mTOR) kinase, function together to control the autophagy and immunometabolism that coordinate the anti-mycobacterial immune defense. Here, we discuss our current understanding of the interplay between autophagy and immunometabolism in terms of combating intracellular Mtb, and how AMPK-mTOR signaling regulates antibacterial autophagy in terms of Mtb infection. We describe several autophagy-targeting agents that promote host antimicrobial defenses by regulating the AMPK-mTOR axis. A better understanding of the crosstalk between immunometabolism and autophagy, both of which are involved in host defense, is crucial for the development of innovative targeted therapies for tuberculosis.
Topics: AMP-Activated Protein Kinases; Animals; Autophagy; Host-Pathogen Interactions; Humans; Immunity, Innate; Mycobacterium tuberculosis; Signal Transduction; TOR Serine-Threonine Kinases; Tuberculosis
PubMed: 33262773
DOI: 10.3389/fimmu.2020.603951