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Mycobacterium brisbanense species nova isolated from a patient with chronic cavitary lung infection

Poh ME, Liam CK, Ng KP, Tan R

Chest, 2014 Apr;145(4):858-860.
PMID: 24687707 DOI: 10.1378/chest.13-1952

We describe the first case, to our knowledge, of Mycobacterium brisbanense species nova with the type strain W6743T (=ATCC 49938T=DSM 44680T) isolated from the lungs of a man with a 6-month history of productive cough and intermittent fever presenting with acute hypoglycemia. A CT scan of the thorax revealed multiple small nodules and consolidation over both lungs with cavitation. Sputum culture repeatedly grew M brisbanense species nova, a novel species never before isolated in Malaysia. The case met the American Thoracic Society criteria for the diagnosis of nontuberculous mycobacterial infection. There was dramatic clinical and radiologic response to treatment with an empirical combination of rifampicin, ethambutol, and levofloxacin and subsequently clarithromycin and levofloxacin once sensitivity was known. This report is the first, to our knowledge, of the pathogen isolated in a patient with chronic cavitary lung infection since it was first identified from an antral sinus in Brisbane, Queensland, Australia, and the first time it is isolated from a human subject in Malaysia.

Matched MeSH terms: Mycobacterium Infections, Nontuberculous/microbiology*
Fulltext MabsBase: a Mycobacterium abscessus genome and annotation database

Heydari H, Wee WY, Lokanathan N, Hari R, Mohamed Yusoff A, Beh CY, et al.

PLoS One, 2013;8(4):e62443.
PMID: 23658631 DOI: 10.1371/journal.pone.0062443

Mycobacterium abscessus is a rapidly growing non-tuberculous mycobacterial species that has been associated with a wide spectrum of human infections. As the classification and biology of this organism is still not well understood, comparative genomic analysis on members of this species may provide further insights on their taxonomy, phylogeny, pathogenicity and other information that may contribute to better management of infections. The MabsBase described in this paper is a user-friendly database providing access to whole-genome sequences of newly discovered M. abscessus strains as well as resources for whole-genome annotations and computational predictions, to support the expanding scientific community interested in M. abscessus research. The MabsBase is freely available at http://mabscessus.um.edu.my.

Matched MeSH terms: Mycobacterium Infections, Nontuberculous/microbiology
A Comparative Genomics Approach for Shortlisting Broad-Spectrum Drug Targets in Nontuberculous Mycobacteria

Swain A, Gnanasekar P, Prava J, Rajeev AC, Kesarwani P, Lahiri C, et al.

Microb Drug Resist, 2021 Feb;27(2):212-226.
PMID: 32936741 DOI: 10.1089/mdr.2020.0161

Many members of nontuberculous mycobacteria (NTM) are opportunistic pathogens causing several infections in animals. The incidence of NTM infections and emergence of drug-resistant NTM strains are rising worldwide, emphasizing the need to develop novel anti-NTM drugs. The present study is aimed to identify broad-spectrum drug targets in NTM using a comparative genomics approach. The study identified 537 core proteins in NTM of which 45 were pathogen specific and essential for the survival of pathogens. Furthermore, druggability analysis indicated that 15 were druggable among those 45 proteins. These 15 proteins, which were core proteins, pathogen-specific, essential, and druggable, were considered as potential broad-spectrum candidates. Based on their locations in cytoplasm and membrane, targets were classified as drug and vaccine targets. The identified 15 targets were different enzymes, carrier proteins, transcriptional regulator, two-component system protein, ribosomal, and binding proteins. The identified targets could further be utilized by researchers to design inhibitors for the discovery of antimicrobial agents.

Matched MeSH terms: Mycobacterium Infections, Nontuberculous/microbiology
Fulltext Molecular typing of Mycobacterium abscessus based on tandem-repeat polymorphism

Wong YL, Ong CS, Ngeow YF

J Clin Microbiol, 2012 Sep;50(9):3084-8.
PMID: 22760048 DOI: 10.1128/JCM.00753-12

A variable-number tandem-repeat (VNTR) typing assay for the differentiation of Mycobacterium abscessus strains was developed. This assay showed complete reproducibility, locus stability, and a discriminatory power (Hunter-Gaston discriminatory index [HGDI] of 0.9563) that is superior to that of multilocus sequencing. It is a promising tool for the investigation of Mycobacterium abscessus epidemiology and nosocomial outbreaks.

Matched MeSH terms: Mycobacterium Infections, Nontuberculous/microbiology
A simple PCR method for rapid genotype analysis of Mycobacterium ulcerans

Stinear T, Davies JK, Jenkin GA, Portaels F, Ross BC, Oppedisano F, et al.

J Clin Microbiol, 2000 Apr;38(4):1482-7.
PMID: 10747130

Two high-copy-number insertion sequences, IS2404 and IS2606, were recently identified in Mycobacterium ulcerans and were shown by Southern hybridization to possess restriction fragment length polymorphism between strains from different geographic origins. We have designed a simple genotyping method that captures these differences by PCR amplification of the region between adjacent copies of IS2404 and IS2606. We have called this system 2426 PCR. The method is rapid, reproducible, sensitive, and specific for M. ulcerans, and it has confirmed previous studies suggesting a clonal population structure of M. ulcerans within a geographic region. M. ulcerans isolates from Australia, Papua New Guinea, Malaysia, Surinam, Mexico, Japan, China, and several countries in Africa were easily differentiated based on an array of 4 to 14 PCR products ranging in size from 200 to 900 bp. Numerical analysis of the banding patterns suggested a close evolutionary link between M. ulcerans isolates from Africa and southeast Asia. The application of 2426 PCR to total DNA, extracted directly from M. ulcerans-infected tissue specimens without culture, demonstrated the sensitivity and specificity of this method and confirmed for the first time that both animal and human isolates from areas of endemicity in southeast Australia have the same genotype.

Matched MeSH terms: Mycobacterium Infections, Nontuberculous/microbiology*
Fulltext Genome sequence of the Mycobacterium abscessus strain M93

Choo SW, Wong YL, Yusoff AM, Leong ML, Wong GJ, Ong CS, et al.

J Bacteriol, 2012 Jun;194(12):3278.
PMID: 22628507 DOI: 10.1128/JB.00492-12

Mycobacterium abscessus is a rapid-growing species of nontuberculous mycobacteria that is frequently associated with opportunistic infections in humans. We report herein the draft genome sequence of M. abscessus strain M93.

Matched MeSH terms: Mycobacterium Infections, Nontuberculous/microbiology
Fulltext Pulmonary non-tuberculous mycobacterial infections: current state and future management

Chin KL, Sarmiento ME, Alvarez-Cabrera N, Norazmi MN, Acosta A

Eur J Clin Microbiol Infect Dis, 2020 May;39(5):799-826.
PMID: 31853742 DOI: 10.1007/s10096-019-03771-0

Currently, there is a trend of increasing incidence in pulmonary non-tuberculous mycobacterial infections (PNTM) together with a decrease in tuberculosis (TB) incidence, particularly in developed countries. The prevalence of PNTM in underdeveloped and developing countries remains unclear as there is still a lack of detection methods that could clearly diagnose PNTM applicable in these low-resource settings. Since non-tuberculous mycobacteria (NTM) are environmental pathogens, the vicinity favouring host-pathogen interactions is known as important predisposing factor for PNTM. The ongoing changes in world population, as well as socio-political and economic factors, are linked to the rise in the incidence of PNTM. Development is an important factor for the improvement of population well-being, but it has also been linked, in general, to detrimental environmental consequences, including the rise of emergent (usually neglected) infectious diseases, such as PNTM. The rise of neglected PNTM infections requires the expansion of the current efforts on the development of diagnostics, therapies and vaccines for mycobacterial diseases, which at present, are mainly focused on TB. This review discuss the current situation of PNTM and its predisposing factors, as well as the efforts and challenges for their control.

Matched MeSH terms: Mycobacterium Infections, Nontuberculous/microbiology*
Fulltext Comparative Genomic Analysis Reveals a Possible Novel Non-Tuberculous Mycobacterium Species with High Pathogenic Potential

Choo SW, Dutta A, Wong GJ, Wee WY, Ang MY, Siow CC

PLoS One, 2016;11(4):e0150413.
PMID: 27035710 DOI: 10.1371/journal.pone.0150413

Mycobacteria have been reported to cause a wide range of human diseases. We present the first whole-genome study of a Non-Tuberculous Mycobacterium, Mycobacterium sp. UM_CSW (referred to hereafter as UM_CSW), isolated from a patient diagnosed with bronchiectasis. Our data suggest that this clinical isolate is likely a novel mycobacterial species, supported by clear evidence from molecular phylogenetic, comparative genomic, ANI and AAI analyses. UM_CSW is closely related to the Mycobacterium avium complex. While it has characteristic features of an environmental bacterium, it also shows a high pathogenic potential with the presence of a wide variety of putative genes related to bacterial virulence and shares very similar pathogenomic profiles with the known pathogenic mycobacterial species. Thus, we conclude that this possible novel Mycobacterium species should be tightly monitored for its possible causative role in human infections.

Matched MeSH terms: Mycobacterium Infections, Nontuberculous/microbiology*
Fulltext A rapid and sensitive system for recovery of nucleic acids from Mycobacteria sp. on archived glass slides

A Talip B, Snelling WJ, Sleator RD, Lowery C, Dooley JSG

BMC Microbiol, 2018 11 26;18(1):196.
PMID: 30477427 DOI: 10.1186/s12866-018-1335-0

BACKGROUND: The field of diagnostics continues to advance rapidly with a variety of novel approaches, mainly dependent upon high technology platforms. Nonetheless much diagnosis, particularly in developing countries, still relies upon traditional methods such as microscopy. Biological material, particularly nucleic acids, on archived glass slides is a potential source of useful information both for diagnostic and epidemiological purposes. There are significant challenges faced when examining archived samples in order that an adequate amount of amplifiable DNA can be obtained. Herein, we describe a model system to detect low numbers of bacterial cells isolated from glass slides using (laser capture microscopy) LCM coupled with PCR amplification of a suitable target.
RESULTS: Mycobacterium smegmatis was used as a model organism to provide a proof of principle for a method to recover bacteria from a stained sample on a glass slide using a laser capture system. Ziehl-Neelsen (ZN) stained cells were excised and catapulted into tubes. Recovered cells were subjected to DNA extraction and pre-amplified with multiple displacement amplification (MDA). This system allowed a minimum of 30 catapulted cells to be detected following a nested real-time PCR assay, using rpoB specific primers. The combination of MDA and nested real-time PCR resulted in a 30-fold increase in sensitivity for the detection of low numbers of cells isolated using LCM.
CONCLUSIONS: This study highlights the potential of LCM coupled with MDA as a tool to improve the recovery of amplifiable nucleic acids from archived glass slides. The inclusion of the MDA step was essential to enable downstream amplification. This platform should be broadly applicable to a variety of diagnostic applications and we have used it as a proof of principle with a Mycobacterium sp. model system.

Matched MeSH terms: Mycobacterium Infections, Nontuberculous/microbiology
Heterogeneity of mycolactones produced by clinical isolates of Mycobacterium ulcerans: implications for virulence

Mve-Obiang A, Lee RE, Portaels F, Small PL

Infect Immun, 2003 Feb;71(2):774-83.
PMID: 12540557

Mycobacterium ulcerans is the causative agent of Buruli ulcer, a severe necrotizing skin disease endemic in tropical countries. Clinical evidence suggests that M. ulcerans isolates from Asia, Mexico, and Australia may be less virulent than isolates from Africa. In vivo studies suggest that mycolactone, a polyketide-derived macrolide toxin, plays a major role in the tissue destruction and immune suppression which occur in cases of Buruli ulcer. Mycolactones were extracted from 34 isolates of M. ulcerans representing strains from Africa, Malaysia, Asia, Australia, and Mexico. Thin-layer chromatography, mass spectroscopic analysis, and cytopathic assays of partially purified mycolactones from these isolates revealed that M. ulcerans produces a heterogeneous mixture of mycolactone variants. Mycolactone A/B, the most biologically active mycolactone species, was identified by mass spectroscopy as [M(+)Na](+) at m/z 765.5 in all cytotoxic isolates except for those from Mexico. Mycolactone C [M+Na](+) at m/z 726.3 was the dominant mycolactone species in eight Australian isolates, and mycolactone D [M+Na](+) m/z 781.2 was characteristic of two Asian strains. Mycolactone species are conserved within specific geographic areas, suggesting that there may be a correlation between mycolactone profile and virulence. In addition, the core lactone, [M+Na](+) m/z 447.4, was identified as a minor species, supporting the hypothesis that mycolactones are synthesized by two polyketide synthases. A cytopathic assay of the core lactone showed that this molecule is sufficient for cytotoxicity, although it is much less potent than the complete mycolactone.

Matched MeSH terms: Mycobacterium Infections, Nontuberculous/microbiology*
Phenotypic and genotypic characteristics of Mycobacterium isolates from fighting fish Betta spp. in Malaysia

Najiah M, Lee KL, Noorasikin H, Nadirah M, Lee SW

Res Vet Sci, 2011 Dec;91(3):342-5.
PMID: 20971487 DOI: 10.1016/j.rvsc.2010.09.010

Mycobacteriosis due to mycobacteria is one of the most common bacterial diseases in ornamental fish. We describe here the phenotypic and genotypic characteristics of Mycobacterium isolates from fighting fish Betta spp. using ATCC Mycobacterium marinum, Mycobacterium fortuitum and Mycobacterium chelonae as references. A total of four isolates (M1, M2, M3, M4) were obtained from four out of 106 fish samples using selective agar, and identified to Mycobacterium genus using acid-fast staining and 16s rRNA gene-based genus specific polymerase chain reaction. DNA sequencing and NCBI-BLAST analysis further identified isolate M1 as M. marinum and isolates M2, M3, M4 as M. fortuitum. Morphological, physiological and biochemical tests were carried out for phenotypic characterizations. Universal M13 and wild-type phage M13 RAPD dendogram was generated to illustrate the genetic relationship of the isolates and reference strains.

Matched MeSH terms: Mycobacterium Infections, Nontuberculous/microbiology
Fulltext Draft genome sequence of Mycobacterium bolletii strain M24, a rapidly growing mycobacterium of contentious taxonomic status

Wong YL, Choo SW, Tan JL, Ong CS, Ng KP, Ngeow YF

J Bacteriol, 2012 Aug;194(16):4475.
PMID: 22843600 DOI: 10.1128/JB.00916-12

The whole-genome sequence of Mycobacterium bolletii M24, isolated from the bronchoalveolar lavage fluid of a Malaysian patient, is reported here. The circular chromosome of 5,507,730 bp helped to clarify the taxonomic position of this organism within the M. abscessus complex and revealed the presence of proteins potentially important for pathogenicity in a human host.

Matched MeSH terms: Mycobacterium Infections, Nontuberculous/microbiology
Analysis of the genome of Mycobacterium abscessus strain M94 reveals an uncommon cluster of tRNAs

Choo SW, Wong YL, Leong ML, Heydari H, Ong CS, Ng KP, et al.

J Bacteriol, 2012 Oct;194(20):5724.
PMID: 23012295

Mycobacterium abscessus is a species of rapidly growing nontuberculous mycobacteria that is frequently associated with opportunistic infections in humans. Here, we report the annotated genome sequence of M. abscessus strain M94, which showed an unusual cluster of tRNAs.

Matched MeSH terms: Mycobacterium Infections, Nontuberculous/microbiology
Fulltext Annotated genome sequence of Mycobacterium massiliense strain M154, belonging to the recently created taxon Mycobacterium abscessus subsp. bolletii comb. nov

Choo SW, Wong YL, Tan JL, Ong CS, Wong GJ, Ng KP, et al.

J Bacteriol, 2012 Sep;194(17):4778.
PMID: 22887675 DOI: 10.1128/JB.01043-12

Mycobacterium massiliense has recently been proposed as a member of Mycobacterium abscessus subsp. bolletii comb. nov. Strain M154, a clinical isolate from the bronchoalveolar lavage fluid of a Malaysian patient presenting with lower respiratory tract infection, was subjected to shotgun DNA sequencing with the Illumina sequencing technology to obtain whole-genome sequence data for comparison with other genetically related strains within the M. abscessus species complex.

Matched MeSH terms: Mycobacterium Infections, Nontuberculous/microbiology
Fulltext Phylogenomics of Brazilian epidemic isolates of Mycobacterium abscessus subsp. bolletii reveals relationships of global outbreak strains

Davidson RM, Hasan NA, de Moura VC, Duarte RS, Jackson M, Strong M

Infect Genet Evol, 2013 Dec;20:292-7.
PMID: 24055961 DOI: 10.1016/j.meegid.2013.09.012

Rapidly growing, non-tuberculous mycobacteria (NTM) in the Mycobacterium abscessus (MAB) species are emerging pathogens that cause various diseases including skin and respiratory infections. The species has undergone recent taxonomic nomenclature refinement, and is currently recognized as two subspecies, M. abscessus subsp. abscessus (MAB-A) and M. abscessus subsp. bolletii (MAB-B). The recently reported outbreaks of MAB-B in surgical patients in Brazil from 2004 to 2009 and in cystic fibrosis patients in the United Kingdom (UK) in 2006 to 2012 underscore the need to investigate the genetic diversity of clinical MAB strains. To this end, we sequenced the genomes of two Brazilian MAB-B epidemic isolates (CRM-0019 and CRM-0020) derived from an outbreak of skin infections in Rio de Janeiro, two unrelated MAB strains from patients with pulmonary infections in the United States (US) (NJH8 and NJH11) and one type MAB-B strain (CCUG 48898) and compared them to 25 publically available genomes of globally diverse MAB strains. Genome-wide analyses of 27,598 core genome single nucleotide polymorphisms (SNPs) revealed that the two Brazilian derived CRM strains are nearly indistinguishable from one another and are more closely related to UK outbreak isolates infecting CF patients than to strains from the US, Malaysia or France. Comparative genomic analyses of six closely related outbreak strains revealed geographic-specific large-scale insertion/deletion variation that corresponds to bacteriophage insertions and recombination hotspots. Our study integrates new genome sequence data with existing genomic information to explore the global diversity of infectious M. abscessus isolates and to compare clinically relevant outbreak strains from different continents.

Matched MeSH terms: Mycobacterium Infections, Nontuberculous/microbiology*
Fulltext Antibiotic resistance in Mycobacterium Abscessus and Mycobacterium Fortuitum isolates from Malaysian patients

Jayasingam SD, Zin T, Ngeow YF

Int J Mycobacteriol, 2017 11 25;6(4):387-390.
PMID: 29171453 DOI: 10.4103/ijmy.ijmy_152_17

BACKGROUND: Rapidly growing mycobacterial species (RGM) are increasingly being recognized as the cause of various superficial and deep infections in humans. Two of the species most frequently isolated from clinical specimens are Mycobacterium abscessus and Mycobacterium fortuitum. Both species are associated with antibiotic resistances that may complicate therapy. This paper describes the pattern of resistance to five antibiotics commonly prescribed for RGM infections, in M. abscessus and M. fortuitum isolated from Malaysian patients.
METHODS: The bacterial strains studied were examined with Etest strips to determine their minimum inhibitory concentrations (MICs) toward amikacin, ciprofloxacin, clarithromycin, imipenem, and linezolid.
RESULTS: Among 51 M. abscessus isolates examined by the Etest, the overall MICs of ciprofloxacin, imipenem, amikacin, clarithromycin, and linezolid showed resistance rates of 33.3%, 31.4%, 2.0%, 5.9%, and 21.6%, to the five antibiotics, respectively. M. abscessus subspecies abscessus was more resistant than M. abscessus subsp. massilience to ciprofloxacin, imipenem, and linezolid but was more susceptible to clarithromycin and amikacin. M. fortuitum isolates were significantly less resistant than M. abscessus to ciprofloxacin (3.6%) and imipenem (7.1%) but more resistant to clarithromycin (42.9%) and linezolid (39.3%).
CONCLUSION: A suitable combination therapy for Malaysian patients would be amikacin plus clarithromycin and ciprofloxacin, to cover infections by all three M. abscessus subspecies and M. fortuitum.

Matched MeSH terms: Mycobacterium Infections, Nontuberculous/microbiology

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