Mycobacteria

No abstract text is available yet for this article.

PII proteins are signal transduction proteins that belong to a widely distributed family of proteins involved in the modulation of different metabolisms in bacteria. These proteins are homotrimers carrying a flexible loop, named T-loop, which changes its conformation due to the recognition of diverse key metabolites, ADP, ATP, and 2-oxoglutarate. PII proteins interact with different partners to primarily regulate a set of nitrogen pathways. In some organisms, PII proteins can also control carbon metabolism by interacting with the biotin carboxyl carrier protein (BCCP), a key component of the acetyl-CoA carboxylase (ACC) enzyme complex, inhibiting its activity with the consequent reduction of fatty acid biosynthesis...

No abstract text is available yet for this article.

RATIONALE: Despite the global increase in nontuberculous mycobacterial pulmonary disease (NTM-PD), there are geographical variations in clinical characteristics. We investigated the clinical characteristics of patients with NTM-PD in South Korea. METHODS: We systematically reviewed articles about patients with NTM-PD in South Korea until February 2022. Individual participant data, regardless of treatment, were collected using a standard case report form. RESULTS: The data of 6,489 patients from 11 hospitals between 2002 and 2019 were analyzed...

People who have structural or developmental lung disease are more likely to develop non-tuberculous mycobacterial infections. We present the case of a young man in his 30s who had unilateral pulmonary artery agenesis on the right side and presented with a 6-month history of productive cough and fever. His CT scan showed nodular and cavitating lesions on the right side, and sputum analysis confirmed infection with Mycobacterium chimaera He had to undergo modifications in his treatment, including a change from rifampicin to rifabutin due to drug interactions and his amikacin had to be stopped due to signs of vestibular toxicity...

Tuberculosis (TB), mainly caused by Mycobacterium tuberculosis, remains the leading cause of death from a bacterium in the world. The global prevalence of clinically relevant infections with opportunistically pathogenic non-tuberculous mycobacteria (NTM) have also been on the rise. Pharmacological treatment of both TB and NTM infections usually requires prolonged regimens of drug combinations, and is often challenging because of developed or inherent resistance to common antibiotic drugs. Medicinal chemistry efforts are thus needed to improve treatment options and therapeutic outcomes...

Microbiology and synthetic biology depend on reverse genetic approaches to manipulate bacterial genomes; however, existing methods require molecular biology to generate genomic homology, suffer from low efficiency, and are not easily scaled to high throughput. To overcome these limitations, we developed a system for creating kilobase-scale genomic modifications that uses DNA oligonucleotides to direct the integration of a non-replicating plasmid. This method, Oligonucleotide Recombineering followed by Bxb-1 Integrase Targeting (ORBIT) was pioneered in Mycobacteria, and here we adapt and expand it for Escherichia coli...

BACKGROUND: This study analyzed the laboratory diagnosis results and drug resistance of patients infected with non-tuberculous mycobacterium (NTM). METHODS: We collected information on patients with positive indicators of NTM infection at the Henan Provincial Chest Hospital from 2020 to 2022. Acid-fast smear, mycobacterium culture, QB-SPOT assay, GeneXpert MTB/RIF assay, immunoglobulin E test, tuberculosis antibody test, and microplate method for drug sensitivity test were analyzed using strain identification as the gold standard...

OBJECTIVE: This study aims to investigate the prevalence of NTM in household water in China and assess its potential role as a source of infection for NTM pulmonary disease, a crucial step for understanding and controlling the spread of this increasingly prevalent disease. METHODS: To examine the prevalence of mycobacteria in household water, 500 mL water samples and swabs were collected from all taps of 19 patients' homes. The amplification of mycobacterial 16SrRNA with bacteriological identification was as a protocol to discriminate mycobacterial isolations from non- mycobacterial isolations...

Mycobacterium abscessus is an emerging pathogen that causes chronic pulmonary infection. Treatment is challenging owing in part to our incomplete understanding of M. abscessus virulence mechanisms that enable pathogen persistence, such as the differing pathogenicity of M. abscessus smooth (S) and rough (R) colony morphotype. While R M. abscessus is associated with chronic infection and worse patient outcomes, it is unknown how immune responses to S and R M. abscessus differ in an acute pulmonary infection setting...

BACKGROUND: Distinguishing between non-tuberculous mycobacterial (NTM) lung infections and pulmonary tuberculosis becomes challenging due to their similar clinical manifestations and radiological images. Consequently, instances of delayed diagnosis or misdiagnosis are highly frequent. A feasible and reliable indicator of the existence of NTM in the early stages of the disease would help to solve this dilemma. METHODS: In this study, we evaluated the potential of smear-positive and Xpert assay (Cepheid, USA) negative outcomes as an early indicator of possible NTM infection in a high TB burden setting retrospectively and prospectively...

BACKGROUND: Culture-free real-time sequencing of clinical metagenomic samples promises both rapid pathogen detection and antimicrobial resistance profiling. However, this approach introduces the risk of patient DNA leakage. To mitigate this risk, we need near-comprehensive removal of human DNA sequences at the point of sequencing, typically involving the use of resource-constrained devices. Existing benchmarks have largely focused on the use of standardized databases and largely ignored the computational requirements of depletion pipelines as well as the impact of human genome diversity...

Diagnosing extrapulmonary tuberculosis (EPTB) is challenging. Immunohistochemistry or immunocytochemistry has been used to diagnose tuberculosis (TB) by detection of MPT64 antigen from various extrapulmonary specimens and has shown good diagnostic performance in our previous studies. The test can distinguish between disease caused by Mycobacterium tuberculosis (Mtb) complex and nontuberculous mycobacteria and can be applied on formalin-fixed paraffin-embedded tissue. As the antibodies previously used were in limited supply, a new batch of polyclonal antibodies was developed for scale-up and evaluated for the first time in this study...

We report a case of an 84-year-old patient with Monoclonal Gammopathy of Undetermined Significance (MGUS) treated with multiple courses of antibiotics and steroids before being diagnosed with Mycobacterium chelonae infection. It is known that MGUS affects both humoral and cellular immunity with impairment of antibody production, function of T-cells, natural killer (NK) cells, and dendritic cells. This case report demonstrates the need to consider patients with MGUS as immunocompromised and draws attention to the correlation between MGUS and Mycobacterium infections...

Since the discovery of extracellular vesicles (EVs) in mycobacterial species 15 years back, we have learned that this phenomenon is conserved in the Mycobacterium genus and has critical roles in bacterial physiology and host-pathogen interactions. Mycobacterium tuberculosis ( Mtb ), the tuberculosis (TB) causative agent, produces EVs both in vitro and in vivo including a diverse set of biomolecules with demonstrated immunomodulatory effects. Moreover, Mtb EVs (MEVs) have been shown to possess vaccine properties and carry biomarkers with diagnostic capacity...

BACKGROUND: Mediastinal infections due to nontuberculous mycobacteria remain an exceedingly rare entity. Most cases in the published literature do not include pediatric patients. Due to their clinical infrequency, poor response to antimicrobial therapy and often precarious anatomical location, the optimal management of these lesions can be challenging. METHODS: Retrospective medical record review of 4 pediatric cases of mediastinal nontuberculous mycobacteria infection was undertaken...

UNLABELLED: Mycobacterium tuberculosis ( Mtb ), the pathogenic bacterium that causes tuberculosis, has evolved sophisticated defense mechanisms to counteract the cytotoxicity of reactive oxygen species (ROS) generated within host macrophages during infection. The melH gene in Mtb and Mycobacterium marinum ( Mm ) plays a crucial role in defense mechanisms against ROS generated during infection. We demonstrate that melH encodes an epoxide hydrolase and contributes to ROS detoxification...

No abstract text is available yet for this article.

BACKGROUND: Improving health-related quality of life (HRQOL) has emerged as a priority in the management of nontuberculous mycobacterial pulmonary disease (NTM-PD). We aimed to evaluate HRQOL and its changes after 6 months' treatment in patients with NTM-PD. METHODS: The NTM-KOREA is a nationwide prospective cohort enrolling patients initiating treatment for NTM-PD in 8 institutions across South Korea. We conducted the Quality of Life-Bronchiectasis (QOL-B) at 6-month intervals and evaluated baseline scores (higher scores indicate better quality of life) and changes after 6 months' treatment...

BACKGROUND: Miliary tuberculosis (TB) is a lethal hematogenous spread form of mycobacterium tuberculosis with approximately 15-20% mortality rate in children. The present report highlights the clinical manifestations of an unusual presentation of miliary tuberculosis in a 12-year-old girl. CASE PRESENTATION: In this case, extensive lung involvement was presented despite the absence of respiratory symptoms. Also, some central hypo-intense with hyper-intense rim nodules were detected in the brain's pons, right cerebral peduncles and lentiform nucleus...