BioAssay record AID 1084112 submitted by ChEMBL: Antibacterial activity against Mycobacterium smegmatis ATCC 607 after 18 hr by agar well diffusion method.
Mycobacterium vaccae is a nonpathogenic species of the Mycobacteriaceae family of bacteria that lives naturally in soil. Its name originates from the Latin word, vacca (cow), since it was first cultured from cow dung in Austria. Research areas being pursued with regard to killed Mycobacterium vaccae vaccine include immunotherapy for allergic asthma, cancer, depression, leprosy, psoriasis, dermatitis, eczema and tuberculosis. A research group at Henry Wellcome Laboratories for Integrative Neuroscience and Endocrinology, University of Bristol, Bristol, England, UK has shown that Mycobacterium vaccae stimulated a newly discovered group of neurons, increased levels of serotonin and decreased levels of anxiety in mice. Other researchers fed live Mycobacterium vaccae to mice, then measured their ability to navigate a maze compared to control mice not fed the bacteria. Mice that were fed live M. vaccae navigated the maze twice as fast and with less demonstrated anxiety behaviors as control mice, ...
Although many of the genic features in Mycobacterium abscessus have been fully validated, a comprehensive understanding of the regulatory elements remains lacking. Moreover, there is little understanding of how the organism regulates its transcriptomic profile, enabling cells to survive in hostile environments. Here, to computationally infer the gene regulatory network for Mycobacterium abscessus we propose a novel statistical computational modelling approach: BayesIan gene regulatory Networks inferreD via gene coExpression and compaRative genomics (BINDER). In tandem with derived experimental coexpression data, the property of genomic conservation is exploited to probabilistically infer a gene regulatory network in Mycobacterium abscessus.Inference on regulatory interactions is conducted by combining primary and auxiliary data strata. The data forming the primary and auxiliary strata are derived from RNA-seq experiments and sequence information in the primary organism Mycobacterium abscessus as
Mycobacterium avium-intracellularae complex (MAC): Nonphotochromogens These Non Tuberculous Mycobacteria (NTM) are classified as Nonphotochromogens in Runyon classification. M avium complex were first recognized as human pathogens in 1990s. They are the important pathogen in immunocompromised and immunocompetent populations.. They are ubiquitous in the environmental sources including natural waters; soil etc. Taxonomically, the M. avium-intracellularae complex comprises M. avium, M. intracellularae, M. paratuberculosis, M. lepraemurium and the wood pigeon bacillus.. These organisms causes opportunistic infections in the immunocompromised patients such as individuals infected with HIV. The lungs are primarily affected, but infection can spread to other organs as well. Disseminated disease is seen in case of AIDS patient.. Mycobacterium fortuitum complex (Rapid growers). It is a group of free living; rapid growing NTM. The colonies of these organisms appear on solid media in 7 days or less. ...
Mycobacterium celatum has been shown to cause disease in immunocompromised patients. We report a case of serious pulmonary infection caused by M. celatum in an apparently immunocompetent patient and review the characteristics of two other reported cases. Clinical and radiologic symptoms and signs included cough, malaise, and weight loss associated with cavitary lesions and pulmonary infiltrates. Although M. celatum is easy to detect in clinical specimens by liquid and solid media, it may be misidentified as a member of the M. tuberculosis complex or as M. xenopi. M. celatum pulmonary infection appears to respond to antimycobacterial chemotherapy, particularly with clarithromycin ...
Mycobacterium celatum has been shown to cause disease in immunocompromised patients. We report a case of serious pulmonary infection caused by M. celatum in an apparently immunocompetent patient and review the characteristics of two other reported cases. Clinical and radiologic symptoms and signs included cough, malaise, and weight loss associated with cavitary lesions and pulmonary infiltrates. Although M. celatum is easy to detect in clinical specimens by liquid and solid media, it may be misidentified as a member of the M. tuberculosis complex or as M. xenopi. M. celatum pulmonary infection appears to respond to antimycobacterial chemotherapy, particularly with clarithromycin.
Mycobacterium goodii is an acid-fast bacterial species in the phylum Actinobacteria and the genus Mycobacterium. M. goodii cells are Gram-positive, nonmotile, acid-fast rods. Colonies of M. goodii are smooth to mucoid, off-white to cream coloured. in After 10-14 days incubation, 78% of all strains produce a yellow or orange pigment.[citation needed] Strains of M. goodii show rapid growth on Middlebrook 7H10 and trypticase soy agar at 30°C, 35°C and 45°C within 2-4 days. They are susceptible to the antibiotics amikacin, ethambutol, and sulfamethoxazole but show intermediate susceptibility to ciprofloxacin, doxycycline and tobramycin and variable susceptibility to cefmetazole, cefoxitin and clarithromycin. They are resistant to isoniazid and rifampicin. M. goodii is found in many of the same settings as M. smegmatis and members of the M. fortuitum complex. It can cause post-traumatic wound infections especially those following open fractures and with associated osteomyelitis and chronic lipoid ...
Radhika Pothi (2013); Anti-Oxidant enzyme levels and quantification of Reactive oxygen species in Mycobacterium aurum Int. J. of Adv. Res. (8). 0] (ISSN 2320-5407). www.journalijar.com. ...
A previously undescribed, slowly growing, non-chromogenic mycobacterium, isolated from a Korean patient with a symptomatic pulmonary infection, is described as representing a novel species. Its 16S rRNA gene sequence was unique and phylogenetic analysis based on 16S rRNA gene sequences showed that this organism belonged to the Mycobacterium terrae subclade. Phenotypically, the strain was generally similar to M. terrae and Mycobacterium nonchromogenicum, but its growth rate was slower than those of other M. terrae complex strains. A unique mycolic acid profile and phylogenetic analysis based on two different alternative chronometer molecules, hsp65 and rpoB, confirm the taxonomic status of this strain as a representative of a novel species. The name Mycobacterium senuense sp. nov. is proposed, with the type strain 05-832T (=DSM 44999T =KCTC 19147T).
Mycobacterium abscessus is a pathogenic, rapidly growing mycobacterium responsible for pulmonary and cutaneous infections in immunocompetent patients and in patients with Mendelian disorders, such as cystic fibrosis (CF). Mycobacterium abscessus is known to transition from a smooth (S) morphotype with cell surface-associated glycopeptidolipids (GPL) to a rough (R) morphotype lacking GPL. Herein, we show that M. abscessus S and R variants are able to grow inside macrophages and are present in morphologically distinct phagosomes. The S forms are found mostly as single bacteria within phagosomes characterized by a tightly apposed phagosomal membrane and the presence of an electron translucent zone (ETZ) surrounding the bacilli. By contrast, infection with the R form leads to phagosomes often containing more than two bacilli, surrounded by a loose phagosomal membrane and lacking the ETZ. In contrast to the R variant, the S variant is capable of restricting intraphagosomal acidification and induces less
Published studies indicate that mycobacterial lipid antigens may stimulate CD1-restricted T cells. However, the pool of studied mycobacterial antigenic lipids is small compared with the diversity of the lipid components of the M. tuberculosis envelope. So far, only three classes of molecules were shown to stimulate CD1b-restricted T cells: free mycolic acids (13), mycoloyl glycolipids such as glucose monomycolate (17), and phosphoglycolipids represented by lipoarabinomannan (19), lipomannan (19), and PIM (20). These molecules are commonly present in the envelope of both virulent and nonvirulent mycobacteria. Their immunogenicity during infection with virulent or avirulent strains has not been compared.. In these studies we have characterized the structure of a novel mycobacterial glycolipid, a diacylated sulfoglycolipid (Ac2SGL), presented by CD1b on the cell surface of M. tuberculosis-infected APCs. This antigen stimulates bactericidal CD8+ T cells and evokes strong responses in healthy PPD+ ...
Recently, we introduced a temperature sensitive Mycobacterium spp., Mycobacterium paragordonae (Mpg). Here, we checked its potential as a candidate for live vaccination against Mycobacterium tuberculosis and Mycobacterium abscessus. Intravenous infections of mice with Mpg led to lower colony forming units (CFUs) compared to infection with BCG, suggesting its usefulness as a live vaccine. The analyses of immune responses indicated that the highly protective immunity elicited by Mpg was dependent on effective dendritic maturation, shift of cytokine patterns and antibody production toward a Th1 phenotype, and enhanced cytotoxic T cell response. Compared to BCG, Mpg showed a more effective protective immune response in the vaccinated mice against challenges with 2 different mycobacterial strains, M. tuberculosis H37Ra or M. abscessus Asan 50594. Our data suggest that a temperature sensitive Mpg may be a potentially powerful candidate vaccine strain to induce enhanced protective immune responses against M.
Tuberculosis was declared a global emergency by the WHO in 1993. Nevertheless, this infectious disease is still one of the most devastating bacterial diseases worldwide, with high rates of morbidity and mortality, and of increasing concern related to the emergence of MDR and XDR strains [15, 16]. Rational development of new anti-TB agents will benefit from the use of new approaches to understand the genetics and physiology of M. tuberculosis. The availability of the genome sequence of M. tuberculosis [17] and powerful genetic tools has provided valuable information about some potential drug targets. M. marinum [18] and M. smegmatis [19] are already used as model species to study the genetics and physiology of M. tuberculosis, and for drug discovery. The use of a new model strain for drug discovery could help identify to new targets and pathways involved in mycobacterial drug resistance. M. aurum is a fast-growing mycobacterium with a doubling time of ~3 h and does not require biosafety level 3 ...
Mycobacterium smegmatis ATCC ® 607™ Designation: TypeStrain=False Application: Assay of bleomycin Bacteriophage host Pharmaceutical and Personal Care
Mycobacterium smegmatis ATCC ® 607™ Designation: TypeStrain=False Application: Assay of bleomycin Bacteriophage host Pharmaceutical and Personal Care
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Learn more from our partner Fujirebio INNO-LiPA MYCOBACTERIA v2. This is a line probe assay for the simultaneous detection and identification of the genus Mycobacterium and 16 different mycobacterial species: https://www.fujirebio.com/en/products-solutions/innolipa-mycobacteria-v2
Mycobacterium is a genus of bacteria, with about 100 species.The genus includes pathogens known to cause serious diseases in mammals, including tuberculosis (Mycobacterium tuberculosis) and leprosy (Mycobacterium leprae).[1] Mycobacteria can colonize their hosts without the hosts showing any adverse signs. Many people around the world have infections of M. tuberculosis without showing any signs of it. Mycobacterial infections are difficult to treat. The organisms are tough due to their cell wall.[2] In addition, they are naturally resistant to a number of antibiotics that disrupt cell-wall building, such as penicillin. With their unique cell wall, they can survive long exposure to acids, alkalis, detergents, oxidative bursts, lysis by complement, and many antibiotics. Most mycobacteria are susceptible to the antibiotics clarithromycin and rifamycin, but antibiotic-resistant strains have emerged. The Greek prefix myco means fungus. When they are cultured on the surface of liquids, mycobacteria ...
The suitability of random amplified polymorphic DNA-PCR for the detection of differences between Mycobacterium malmoense strains was evaluated. With two of the 32 tested primers seven fingerprint patterns which proved excellent in distinguishing intraspecies variations of M. malmoense were obtained. The combination of the results obtained with the two primers permitted a clear separation of the strains. This technique is useful for analyzing species whose DNA sequences are not known. It can easily be adapted to test any mycobacterial species. ...
Mycobacteria were detected in 39 per cent (143/363) of the examined lymph nodes, 63 per cent (59/93) of lymph nodes with gross lesions typical of mycobacteriosis and 31 per cent (84/270) of lymph nodes with no visible lesions. Nineteen per cent of the isolated mycobacteria were identified as Mycobacterium avium, of these 78 per cent and 22 per cent were M. avium sub sp. Hominissuis and avium, respectively. Other mycobacterial species included M. senuense (16 per cent), M. terrae (seven per cent) and M. asiaticum (six per cent ...
Article: Chen S, Adams A, Thompson K & Richards R (1997) Development of monoclonal antibodies to the extracellular products of Mycobacterium spp. Isolated from chevron snakehead and the reference strain Mycobacterium chelonei. Journal of Aquatic Animal Health, 9 (2), pp. 86-98. https://doi.org/10.1577/1548-8667%281997%29009%3C0086%3ADOMATT%3E2.3.CO%3B2
Background. Mycobacterium abscessus can produce a chronic pulmonary infection for which little is known regarding optimal treatment and long-term outcomes.. Methods. We performed a retrospective observational study (2001-2008) including all patients who met American Thoracic Society criteria for M. abscessus pulmonary disease. Our aim was the evaluation of clinical and microbiologic outcomes in patients treated with combined antibiotic and surgical therapy, compared with antibiotic therapy alone.. Results. A total of 107 patients were included in the analysis. Patients were predominantly female (83%) and never-smokers (60%), with a mean age of 60 years. Fifty-nine (55%) of 107 patients had coexistent or previous history of Mycobacterium avium complex pulmonary infection. High-resolution chest CT showed bronchiectasis and nodular opacities in 98% of patients and cavities in 44%. Sixy-nine (46 medical, 23 surgical) patients were followed up for a mean duration of 34 months (standard deviation, ...
Many things may affect your lab test results. These include the method each lab uses to do the test. Even if your test results are different from the normal value, you may not have a problem. To learn what the results mean for you, talk with your healthcare provider. A normal result for an acid-fast bacteria smear is negative, meaning no bacteria were found in the sputum sample. A positive result means that bacteria were found and that you may have an infection. The smear is treated with a special acid-fast stain that can provide a preliminary test result in 24 hours. At the same time, another sample of sputum is also tested as a culture. This means the sample will be used to grow the bacteria in a lab if they are present. The culture provides a more definite result, but it can take several weeks to determine a positive or negative diagnosis. ...
Specific species of NTM such as MABSC organisms are considered significant CF pathogens and are associated with poorer clinical outcomes (14). The isolation of NTM from respiratory samples of CF patients is challenging because of bacterial and fungal overgrowth in AFB cultures. RGM medium, a novel selective medium designed for the isolation of MABSC organisms, has been shown to have promise for the isolation of rapidly growing mycobacteria from the sputa of CF patients (11-13). We are the first U.S. center to evaluate this medium with the largest number of samples to date. Extending the incubation time of RGM medium from 10 to 28 days and comparison between RGM medium and 8-week AFBC using an MGIT and LJ medium were intended to give a preliminary assessment of the ability to detect slowly growing mycobacteria on this medium.. RGM medium is superior to BCSA for the recovery of rapidly growing mycobacteria, with a sensitivity for the detection of NTM on RGM medium of 96.9%, compared with 35.7% on ...
The nuoG gene of Mycobacterium tuberculosis (Mtb) has the ability to inhibit host cell apoptosis. This ability is a virulence factor and does not exist in facultative pathogenic and non-pathogenic mycobacterial species. NuoG is part of the NDH-1 complex, and this study addressed the potential link between the role of NuoG in apoptosis inhibition and the biochemical activity of the NDH-1 complex. Different mycobacterial species were tested for their NDH-1 activities. Among the bacteria tested were bacteria transformed with the Mtb nuoG plasmid, or with the almost entire NDH-1 coding region. Surprisingly, the levels of NDH-1 activity did not correlate with apoptosis levels, suggesting a potential independent, novel mechanism by which NuoG inhibits host cell apoptosis. ...
Zoé Cavalli1, Quitterie Reynaud1, Romain Bricca, Raphaële Nove-Josserand, Stéphane Durupt, Philippe Reix, Marie Perceval, Michèle Pérouse de Montclos, Gérard Lina, Isabelle Durieu ...
GTPase high frequency of lysogenization X (HflX) is highly conserved in prokaryotes and acts as a ribosome-splitting factor as part of the heat shock response in Escherichia coli. Here we report that HflX produced by slow-growing Mycobacterium bovis bacillus Calmette-Guérin (BCG) is a GTPase that plays a critical role in the pathogens transition to a nonreplicating, drug-tolerant state in response to hypoxia. Indeed, HflX-deficient M. bovis BCG (KO) replicated markedly faster in the microaerophilic phase of a hypoxia model that resulted in premature entry into dormancy. The KO mutant displayed hallmarks of nonreplicating mycobacteria, including phenotypic drug resistance, altered morphology, low intracellular ATP levels, and overexpression of Dormancy (Dos) regulon proteins. Mice nasally infected with HflX KO mutant displayed increased bacterial burden in the lungs, spleen, and lymph nodes during the chronic phase of infection, consistent with the higher replication rate observed in vitro in ...
Taxonomic studies were performed on a phenotypically homogeneous group of 13 mycobacteria isolated from clinical, veterinary and stream-water samples. The methods applied included chromatographic analyses of bacterial lipids, biochemical tests and sequencing of the 16S rDNA and the internal transcribed spacer 1 (ITS1) region. Positive results in urease, Tween 80 hydrolysis and pyrazinamidase tests and a negative result in a semi-quantitative catalase test, combined with the ability to grow at 42 degrees C, distinguished this group among the yellow-pigmented, slowly growing mycobacteria. Unique fatty acid and mycolic acid profiles in chromatographic analyses and the results of gene sequencing indicated that the novel isolates represent a previously undescribed species, for which the name Mycobacterium palustre sp. nov. is proposed. The fatty acid profile obtained by GLC was characterized by the presence of several methyl-branched fatty acid markers. The most prominent markers were 2-methyleicosanoic,
Characterization of a pyrene-degrading Mycobacterium sp. strain CH-2.: Mycobacterium sp strain CH-2 was isolated from a manufactured gas plant contaminated with
Fingerprint Dive into the research topics of Impaired fitness of Mycobacterium africanum despite secretion of ESAT-6. Together they form a unique fingerprint. ...
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The number of mycobacteria required to establish an infection is extremely low. Mycobacterium tuberculosis, an obligate pathogen, can establish infection with as few as one to ten bacteria. Compare this to the one hundred thousand bacteria required to establish a Salmonella infection. This indicates that the immune system can be very unsuccessful at combatting these organisms.. When pathogenic mycobacteria enter the body, they are very successful at evading the bodies defenses. Their waxy coat helps to protect them against the high acidity of the stomach. The surfactant (soap-like) qualities of bile salts are not powerful enough to wash away their waxy coat. Also, they are not susceptible to the anti-biotic chemicals produced by the normal flora.. Once at their preferred site of infection, pathogenic mycobacteria tend to allow themselves to be phagocytosed(swallowed) by Macrophages(white blood cells), within which they are able to resist destruction, and are able to multiply. The host immune ...
The VisionArray MYCO PreCise Master Mix is a ready to use PCR Master Mix for amplifying ITS and, in case of M. tuberculosis complex, IS6110 region of mycobacterial genomes including but not limited to those detected by the VisionArray MYCO Chip. The VisionArray MYCO PreCise Master Mix contains the VisionArray MYCO Primer Mix 1.0, dNTP/dUTP Solution, the VisionArray PreCise Taq DNA Polymerase, the PCR-Buffer, MgCl2, and the VisionArray Uracil-DNA Glycosylase. During PCR, specific sections of the ITS and IS6110 region of the mycobacterial genomes will be biotinylated. The hybridization and detection of the amplified sequences is subsequently performed using the VisionArray Detection Kit and the VisionArray MYCO Chip.. ...
Whole genome sequencing approach followed by the comparative genomic analysis has provided useful insights into the genome dynamics of M. abscessus species. In this study, the genetic variations in M. abscessus clinical strains were explored. We believe this is the first study to analyze the respective methylomes of M. abscessus clinical strains. The genetic information of M. abscessus is necessary for understanding its complex lifestyle in natural conditions. The genome of this pathogen is containing a large number of genes encoding antibiotic-target-modifying enzymes responsible for intrinsic resistance to a wide range of antibiotics as well as genes associated with intracellular survivability and parasitism (Ripoll et al. 2009; Luthra et al. 2018). Additionally, M. abscessus exhibits two morphological characteristics like smooth phenotype which expresses glycopeptidolipid (GPL) on its cell wall and rough phenotype without GPL expression (Pawlik et al. 2013). The virulence potential of rough ...
From my showerhead, most microbes identified were unknown (63.75%), followed by Mycobacterium (31.34%), Sphingomonas (3.28%), and Sphingopyxis (1.05%). The abundance of the rest of the microbes was less than 0.5%.. When you think of mycobacterium, tuberculosis (caused by Mycobacterium tuberculosis) and leprosy (caused by Mycobacterium leprae) jump to mind. Surely, these pathogens cant be living in my shower, right? The Mycobacterium genus consists of over 190 species, including non-pathogens found in soil, tap water, estuaries, and dust. However, Mycobacterium avium, was identified 20% of showerheads from an earlier study from Norman Paces lab. M. avium is an opportunistic pathogen that causes chronic pulmonary disease, particularly in people with immunodeficiencies. M. avium can cause disease only when it is aerosolized i.e. when showers produce a fine mist of water droplets. In an interview with NPRs Ira Flatow, Pace advises taking baths instead of showers to avoid contracting M. avium if ...
Analysis of the reference M. abscessus ATCC 19977 complete genome sequence yielded 3538 intergenic spacers with , 300 spacers were 200-700 bp in length. Successful PCR sequencing was achieved for 8 spacers in all the isolates studied; the sequences were deposited in the GenBank database (GenBank accession: KC352850 - KC352890). In M. abscessus isolates, including the 37 sequenced genomes, the spacer sequence variability was generated by one to 12 single nucleotide polymorphisms (SNPs) (spacers n°1 and n°8), one to 18 SNPs and one to two nucleotide deletions (spacer n°2), one to two SNPs (spacers n°3 and n°7) and nucleotide insertion (spacers n°2 and n°5). In M. bolletii isolates, the spacer sequence polymorphisms were generated by one SNP for spacer n°1, two SNPs and one deletion for spacer n°2, two SNPs for spacer n°3 and nine SNPs for spacer n°7. In M. massiliense isolates, including 28 sequenced genomes, the spacer sequence polymorphism were generated by nine SNPs and one ...
Skin infected with M. abscessus is usually red, warm, tender to the touch, swollen, and/or painful. Infected areas can also develop boils or pus-filled vesicles. Other signs of M. abscessus infection are fever, chills, muscle aches, and a general feeling of illness. However, for a definite diagnosis, the organism has to be cultured from the infection site or, in severe cases, from a blood culture. A medical provider should evaluate the infection to determine if it may be due to M. abscessus.. Diagnosis is made by growing this bacterium in the laboratory from a sample of the pus or biopsy of the infected area. When the infection is severe, the bacterium can be found in the blood and isolated from a blood sample. To make the diagnosis, your healthcare provider will have to take a sample from the infected area and/or blood and send it to a laboratory for identification. It is important that persons who have any evidence of infection at a site where they received procedures, such as surgery or ...
What did you find?. Receptors on cell surfaces are analogous to antennae, sensing what is in the local environment. Toll-like receptors (TLRs) are linked at the cell surface and recognize NTM. We found that CFBE41o‐ cells do not respond to M. abscessus due to a variation in the gene. This variation is called I602S and renders TLR1 nonfunctional. It is very common in Caucasians of northern European ancestry, the same population in which the CF ΔF508 is common, and it influences susceptibility to infection with other mycobacteria. ...
Looking for Mycobacterium genovense? Find out information about Mycobacterium genovense. a genus of bacteria, related to actinomycetes; it differs from true bacteria in a number of ways. The young vegetative cells are rodlike ; they are capable... Explanation of Mycobacterium genovense
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UK Standards for Microbiology Investigations B 37: Investigation of blood cultures (for organisms other than Mycobacterium species).
In this investigation, we have used transposon mutagenesis to identify a novel mycobacterial protein that is associated with phenotypic changes in the parent strain that alter the adhesive properties of the mycobacteria. Recently, a similar BCG transposon library was used to identify a mycolic acid cyclopropane synthetase as a virulence factor in M. tuberculosis by screening for variants that are deficient in cord formation (20). For our investigation, we reasoned that a mutant which exhibited a nonaggregative morphology may identify a gene that influences the interaction of mycobacteria with other cells, since there is evidence that adhesins can also induce autoaggregation of bacteria (9, 32). In fact, it has previously been shown that the mycobacterial adhesin HBHA promotes bacterial aggregation (16, 31, 33).. In this study, after screening more than 1,900 BCG transposon insertion mutants, one mutant strain, mc21525, was singled out for demonstrating an obvious difference in clumping ...
Mycobacterium sp., ATCC-25034, from Microorganisms. High-quality, certified reference materials, available to purchase online at LGC Standards.
The genus Mycobacterium comprises clinically important pathogens such as M. tuberculosis, which has reemerged as a major cause of morbidity and mortality world-wide especially with the emergence of multidrug-resistant strains. The use of fast-growing species such as Mycobacterium smegmatis has allow …
Although gyrA, gyrB, hsp65, recA, rpoB, and sodA genes are appropriate for identification purposes [3, 4], our results emphasized that these genes seem inappropriate for specific detection of mycobacteria. Indeed, their high similarities with non-mycobacterial genes make specific target design delicate. These new results are in accordance with our previous observations that the molecular targets which were designed based on gyrB [18], rpoB[19] or hsp65[20] genes, had low specificity [17]. For example, the non-related Helicobacter pylori show positive amplification with several Mycobacterium specific primer pairs [17]. Prospection for more specific targets in mycobacterial genomes seems consequently necessary in order to improve current detection tools based on proteins and/or DNA. The new atpE real-time PCR method that we propose is just as specific, but more sensitive than the previously proposed rrs real-time PCR method which cannot detect some mycobacterial species [17].. The proposed ...
This test looks for a type of bacteria called acid-fast bacillus in your sputum. Tuberculosis is the most common infection from this type of bacteria.
Among the rapidly growing mycobacteria (RGM), the members of the Mycobacterium fortuitum complex are the species most often associated with human infections (11). Therapy of these infections is quite different from the treatment of tuberculosis and also from the treatment of disease caused by other, slowly growing mycobacteria (2). There are many differences in the susceptibility of the members of this group of mycobacteria in published studies, and several of them revealed that in vitro susceptibility correlates with clinical response to therapy (10). Here we report a study of the in vitro susceptibility of these species to some antimicrobials, including newly developed ones.. A total of 94 (Mycobacterium fortuitum [48 strains],Mycobacterium chelonae [25 strains], Mycobacterium mucogenicum [3 strains], Mycobacterium peregrinum[12 strains], and Mycobacterium abscessus [6 strains]) strains of RGM isolated from clinical samples were tested. Prior to testing, strains were subcultured, checked for ...
Looking for online definition of mycobacterium simiae complex in the Medical Dictionary? mycobacterium simiae complex explanation free. What is mycobacterium simiae complex? Meaning of mycobacterium simiae complex medical term. What does mycobacterium simiae complex mean?
The pentose phosphate pathway is a process of glucose turnover that produces NADPH as reducing equivalents and pentoses as essential parts of nucleotides. There are two different phases in the pathway. One is irreversible oxidative phase in which glucose-6P is converted to ribulose-5P by oxidative decarboxylation, and NADPH is generated [MD:M00006]. The other is reversible non-oxidative phase in which phosphorylated sugars are interconverted to generate xylulose-5P, ribulose-5P, and ribose-5P [MD:M00007]. Phosphoribosyl pyrophosphate (PRPP) formed from ribose-5P [MD:M00005] is an activated compound used in the biosynthesis of histidine and purine/pyrimidine nucleotides. This pathway map also shows the Entner-Doudoroff pathway where 6-P-gluconate is dehydrated and then cleaved into pyruvate and glyceraldehyde-3P [MD:M00008 ...
Several groups have demonstrated the use of suicide plasmids for allelic exchange in fast- and slow-growing mycobacteria. The most efficient are those systems using a counterselectable marker; for mycobacteria, workers have successfully used rpsL (36,42), pyrF (26), and sacB(40). The most promising counterselectable system for the slow-growing mycobacteria is sacB, which confers sensitivity to sucrose. Methods using sacB were used for the targeted disruptions of ureC in M. bovis BCG (40) and M. tuberculosis (37) and theerp gene of M. bovis BCG and M. tuberculosis (8).. We decided to construct a new sacB suicidal vector, pYUB657, and test it for the construction of unmarked, in-frame deletion mutants in the slow-growing mycobacteria. In these studies, we saw an opportunity to examine homologous recombination in the mycobacteria from a practical standpoint. The bane of allelic exchange in slow-growing mycobacteria has been the propensity with which these organisms incorporate exogenous DNA into ...
TY - JOUR. T1 - Mycobacterium abscessus D-alanyl-D-alanine dipeptidase induces the maturation of dendritic cells and promotes Th1-biased immunity. AU - Lee, Seung Jun. AU - Jang, Jong Hwa. AU - Yoon, Gun Young. AU - Kang, Da Rae. AU - Park, Hee Jo. AU - Shin, Sung Jae. AU - Han, Hee Dong. AU - Kang, Tae Heung. AU - Park, Won Sun. AU - Yoon, Young Kyung. AU - Soh, Byoung Yul. AU - Jung, In Duk. AU - Park, Yeong Min. PY - 2016. Y1 - 2016. N2 - Mycobacterium abscessus, a member of the group of non-tuberculous mycobacteria, has been identified as an emerging pulmonary pathogen in humans. However, little is known about the protective immune response of antigenpresenting cells, such as dendritic cells (DCs), which guard against M. abscessus infection. The M. abscessus gene MAB1843 encodes D-alanyl-D-alanine dipeptidase, which catalyzes the hydrolysis of D-alanyl-D-alanine dipeptide. We investigated whether MAB1843 is able to interact with DCs to enhance the effectiveness of the hosts immune response. ...
OBJECTIVES: To determine the clinical relevance of Mycobacterium chelonae-abscessus group isolation from clinical samples. METHODS: We retrospectively reviewed medical files of all patients from whom these mycobacteria were isolated between January 1999 and January 2005 and re-identified the isolates by rpoB sequencing. We applied the American Thoracic Society (ATS) diagnostic criteria to establish clinical relevance. RESULTS: Ninety-five patients were traced (56 M. chelonae, 25 Mycobacterium abscessus, 8 Mycobacterium massiliense, 6 Mycobacterium bolletii). Most isolates were cultured from pulmonary samples in patients with pre-existing pulmonary disease. Among patients with pulmonary isolates, 27% (20/74) meets ATS criteria; M. abscessus is most relevant (50%; 9/18), followed by M. massiliense (29%; 2/7), M. bolletii (20%; 1/5) and M. chelonae (18%; 8/44). Extrapulmonary disease presented as disseminated skin disease, eye disease specific for M. chelonae and otomastoiditis for M. abscessus. ...
The HIV pandemic raised the potential for facultative-pathogenic mycobacterial species like, Mycobacterium kansasii, to cause disseminating disease in humans with immune deficiencies. In contrast, non-pathogenic mycobacterial species, like M. smegmatis, are not known to cause disseminating disease even in immunocompromised individuals. We hypothesized that this difference in phenotype could be explained by the strong induction of an innate immune response by the non-pathogenic mycobacterial species.. A comparison of two rapid-growing, non-pathogenic species (M. smegmatis and M. fortuitum) with two facultative-pathogenic species (M. kansasii and M. bovis BCG) demonstrated that only the non-pathogenic bacteria induced strong apoptosis in human THP-1 cells and murine bone marrow-derived macrophages (BMDM) and dendritic cells (BMDD). The phospho-myo-inositol modification of lipoarabinomannan (PI-LAM) isolated from non-pathogenic species may be one of the cell wall components responsible for the ...
Paratuberculosis, or Johnes disease, is a disease of domestic and wild ruminants that culminate with a chronic enteritis caused by Mycobacterium avium subsp. paratuberculosis. The aim of this work was to evaluate the type of immune response, Th1 or Th2, induced by DNA vaccinations in lambs of Sarda breed. Twenty-five lambs, serum negative for M. paratuberculosis, were selected at birth from equally serum negative mothers. The lambs were inoculated at 5 months of age with three different mycobacterial antigens cloned into a mammalian expression vector as fusion protein with the enhanced green fluorescent protein (pEGFP-N1). The animals were divided in five groups containing each five lambs. Each group was vaccinated as following (A: physiological solution; B: Gudair™; C: p-85A-Mav; D: p-85A-BCG; E: p-Hsp65). Immune response was evaluated by measuring the expression of INF-γ (Th1 type response) and IL-10 (Th2 type response) by real-time PCR. Gene expression was estimated by comparing the ...
Introduction. Mycobacterium tuberculosis, Mycobacterium bovis, Mycobacterium bovis BCG, Mycobacterium canettii, Mycobacterium africanum, Mycobacterium pinnipedii, Mycobacterium microti, Mycobacterium caprae, the dassie and the oryx bacillus, and the recently discovered Mycobacterium mungi are closely related species that form the M. tuberculosis complex (MTBC). Mycobacterium tuberculosis and M. bovis are the most important species in the complex which commonly cause human and animal tuberculosis (TB), with concomitant negative consequences for human and animal health and economic costs.. The probability of M. bovis transmission is more likely to occur between animals, particularly those in close contact such as herd animals (Grange & Collins 1987). Humans can also be infected by M. bovis from contact with infected animals or animal products and the likelihood of infection and disease, as with human forms of TB are exacerbated by crowding and stress (Figueroa-Munoz & Ramon-Pardo 2008). The ...
Introduction. Mycobacterium tuberculosis, Mycobacterium bovis, Mycobacterium bovis BCG, Mycobacterium canettii, Mycobacterium africanum, Mycobacterium pinnipedii, Mycobacterium microti, Mycobacterium caprae, the dassie and the oryx bacillus, and the recently discovered Mycobacterium mungi are closely related species that form the M. tuberculosis complex (MTBC). Mycobacterium tuberculosis and M. bovis are the most important species in the complex which commonly cause human and animal tuberculosis (TB), with concomitant negative consequences for human and animal health and economic costs.. The probability of M. bovis transmission is more likely to occur between animals, particularly those in close contact such as herd animals (Grange & Collins 1987). Humans can also be infected by M. bovis from contact with infected animals or animal products and the likelihood of infection and disease, as with human forms of TB are exacerbated by crowding and stress (Figueroa-Munoz & Ramon-Pardo 2008). The ...
Mycobacterium smegmatis is 3.0 to 5.0 µm long with a bacillus shape, an acid-fast bacterial species in the phylum Actinobacteria. It can be stained by Ziehl-Neelsen method and the auramine-rhodamine fluorescent method. It was first reported in 1884. Alvarez and Tavel found organisms similar to Lustgarten, who first discovered Mycobacterium. This organism was later named M. smegmatis. It is considered a non-pathogenic microorganism although, in rare cases, it can cause disease. M. smegmatis is useful for the research analysis of other Mycobacteria species in laboratory experiments. Since it is a fast grower and non-pathogenic it makes a simple model that is easy to work with. It shares more than 2000 homologs with M. tuberculosis and shares the same unusual cell wall structure of M. tuberculosis and other mycobacterial species. The discovery of plasmids, phages, and mobile elements has enabled the construction of dedicated gene-inactivation and gene reporter systems. The M. smegmatis strain is ...
Non-tuberculous mycobacteria (NTM) such as Mycobacterium avium intracellulare are commonly encountered by HIV physicians and management strategies are well established. Experience of other NTM is, however, limited. As HIV epidemiology in the United Kingdom changes, we may expect the emergence of these lesser known mycobacterial infections. We present the first UK report of an AIDS patient who has survived infection with disseminated Mycobacterium simiae despite cerebrospinal fluid involvement, an extremely high level of baseline HIV viraemia and treatment complicated by severe immune reconstitution inflammatory syndrome. ...
Vole tuberculosis (TB; Mycobacterium microti) is an understudied endemic infection. Despite progressing slowly, it causes severe clinical pathology and overt symptoms in its rodent host. TB was monitored for 2 years in wild field voles in Kielder Forest, UK. The prevalence of characteristic cutaneous TB lesions was monitored longitudinally at 4 sites, with individuals live-trapped and repeatedly monitored. A prevalence of 5.2% of individuals with lesions was recorded (n=2791). In a cross-sectional study, 27 sites were monitored bi-annually, with TB assessed by post-mortem examination for macroscopic lesions, and by culture and histopathology. Seventy-nine voles (10.78%; n=733) were positive for mycobacteria, with the highest prevalence in spring (13.15%; n=327). TB prevalence varied, with between 0% and 50% of voles infected per site. Prevalence increased with age (mass), and apparent seasonality was due to a higher proportion of older animals in spring. Survival analysis supported this result, ...
Mycobacterium abscessus, a rapidly growing mycobacterium (RGM) and an opportunistic human pathogen, is responsible for a wide spectrum of clinical manifestations ranging from pulmonary to skin and soft tissue infections. This intracellular organism can resist the bactericidal defense mechanisms of amoebae and macrophages, an ability that has not been observed in other RGM. M. abscessus can up-regulate several virulence factors during transient infection of amoebae, thereby becoming more virulent in subsequent respiratory infections in mice. Here, we sought to identify the M. abscessus genes required for replication within amoebae. To this end, we constructed and screened a transposon (Tn) insertion library of an M. abscessus subspecies massiliense clinical isolate for attenuated clones. This approach identified five genes within the ESX-4 locus, which in M. abscessus encodes an ESX-4 type VII secretion system that exceptionally also includes the ESX conserved EccE component. To confirm the ...
The intestinal carriage of nontuberculous mycobacteria (NTM) is associated with disease, especially in severely immunocompromised individuals. These organisms, although often considered contaminants, have been known to cause various types of illnesses. We aimed to determine the prevalence of and associated factors for NTM among patients booked for colonoscopy at the University Teaching Hospital (UTH) in Lusaka. We randomly recruited 97 patients attending routine endoscopy procedures between November 2012 and October 2013 and after consent, administered a structured questionnaire. We collected stool and intestinal lavage samples, as well as biopsy samples from the descending colon and the caecal area during the endoscopy procedure. Samples were cultured using the mycobacteria growth indicator tube (MGIT) method followed by the GenoType Mycobacterium CM/AS assay for identification of NTM. Results were expressed as means and standard deviations; proportions were expressed as percentages with corresponding
Pathogenic mycobacteria use virulence factors, including mannose-capped lipoarabinomannan (ManLAM), to survive in host phagocytic cells, such as neutrophils. We assessed the roles of lactosylceramide (LacCer, CDw17)-enriched lipid rafts in the phagocytosis of mycobacteria by human neutrophils and in the intracellular fate of phagocytosed mycobacteria. We showed that the association of the Src family kinase (SFK) Lyn with C24 fatty acid chain-containing LacCer was essential for the phagocytosis of mycobacteria by neutrophils. Assays with LacCer-containing liposomes, LacCer-coated plastic plates, and LAM-coated beads demonstrated that the phagocytosis of mycobacteria was mediated through the binding of LacCer to LAM. Both ManLAM from pathogenic species and phosphoinositol-capped LAM (PILAM) from nonpathogenic Mycobacterium smegmatis bound equivalently to LacCer to stimulate phagocytosis. However, PILAM from an M. smegmatis α1,2-mannosyltransferase deletion mutant (ΔMSMEG_4247), lacking the ...
Nontuberculosis mycobacteria (NTM) are a diverse group of organisms that are ubiquitous in both natural and manmade environments [1]. Though less notorious than Mycobacterium tuberculosis (MTB), NTM infections are also of clinical significance and have been associated with worldwide outbreaks in the past. A previous study showed that the clinical symptoms and iconography representation of NTM were similar to MTB making it difficult to differentiate between the two diseases. Furthermore, treatment is also more difficult because most of NTM are naturally resistant to anti-tuberculosis drugs [2]. Thus, there is an urgent clinical need for tools that would enable accurate differentiation of MTB from NTM-induced disease. Since the genomes of different mycobacteria have been sequenced, it is now possible for us to generate a novel DNA barcoding technology for genotyping of mycobacteria.. Clinically, mycobacteria were traditionally characterized based on acid-fastness, smear and culture morphology, ...
Background: Non-tuberculous mycobacteria (NTM) pulmonary infections are an emerging issue in the cystic fibrosis (CF) population. In Europe, Mycobacterium abscessus complex (MABSC), which may cause accelerated lung function decline, is the predominant species of NTM in patients with CF. In our clinical practice, isolation of mycobacteria consists of culture of decontaminated sputum on solid media (Lowenstein medium) and automated liquid broth method (MGIT™, Becton Dickinson®). Unfortunately, due to bacteria and fungi overgrowth, isolation of mycobacteria from sputum of these patients remains challenging. Indeed, pulmonary tract of patients with cystic fibrosis is known to be frequently colonised by microorganisms which grow faster and resist to decontamination. RGM medium is a novel agar-based culture medium which contains growth factors and selective agents to allow isolation of rapidly-growing mycobacteria. Material/methods: We evaluated RGM medium on 102 sputa of patients with CF. Samples ...
Mycobacteria are nonmotile, aerobic, weakly gram-positive, but acid-fast; in smears, they appear as straight or slightly curved rods. Löwenstein-Jensen medium is most commonly used for culture isolation. Mycobacteria are obligate intracellular pathogens and are divided into 2 main groups based on their growth rate. Mycobacterium tuberculosis and Mycobacterium leprae are slow growers. Ocular infection by M tuberculosis is uncommon, but it can manifest as a scleritis or posterior uveitis. The fast-growing atypical mycobacteria, including Mycobacterium fortuitum and Mycobacterium cheloneae, are a more common cause of ulcerative keratitis in the setting of an immunocompromised ocular surface or refractive surgery. Although their importance as a cause of keratitis following refractive surgery remains, atypical mycobacteria have been supplanted by MRSA as the predominant causative agent in this setting.. ...
Qxd 12/22/07 11:24 AM Page 37 ACID-FAST BACILLI: MYCOBACTERIUM pigmented, although a rare yellow-pigmented colony form may be encountered. Two colony morphotypes, rough and smooth, are especially evident on serumbased media such as Middlebrook 7H10 and 7H11 agar. Mycobacterium kansasii This species is photochromogenic, producing bright yellow colonies upon exposure to light. M. kansasii is found in tap water and has caused pulmonary, cervical lymphadenitis (especially in children), cutaneous, and disseminated infections. Because of the reduction in the chain length of their cell wall fatty acid composition, these species not only grow more rapidly, but stain weakly Gram-positive and hence can mimic Corynebacterium species (diphtheroids). Figure 126 Mycobacterium fortuitum Ulcerated lesion of leg with sinus tracts which developed post-cosmetic fat transplant to leg. qxd 12/22/07 11:24 AM Page 41 ACID-FAST BACILLI: MYCOBACTERIUM Figure 130 Mycobacterium chelonei Abscess of leg with necrotic ...
To the editor: We recently treated a patient with the acquired immunodeficiency syndrome and disseminated infection due to Mycobacterium gordonae. Infection with this organism has not previously been reported in association with the syndrome.. A 41-year-old man who abused intravenous drugs developed Pneumocystis carinii pneumonia in November 1981. He responded to treatment with intravenous sulfamethoxazole and trimethoprim. In July 1982 he developed esophageal candidiasis which was treated with ketoconazole. The next month, a sputum specimen showed acid-fast bacilli on stain. He was treated by his physician with isoniazid. In November 1982, because of persistent fever and weakness, a bone marrow ...
The burden of non-tuberculous mycobacterial (NTM) disease is increasing worldwide but still its diagnosis is delayed and it is mistaken as multidrug-resistant tuberculosis (MDR-TB).The present study was performed to develop a multiplex PCR assay for detection and identification of clinically most common NTM to the species level from pulmonary samples. Out of 50 isolates, 26 were identified as Mycobacterium kansasii (MK), 20 were identified as Mycobacterium abscessus (MA) and 4 were identified as Mycobacterium avium complex (MAC) through multiplex PCR and further confirmed by sequencing. Our study showed that multiplex PCR assay is a simple, convenient, and reliable technique for detection and differential identification of major NTM species.
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Wissenschaftlicher Name Mycobacterium smegmatis (Trevisan 1889) Lehmann & Neumann 1899 Mycobacterium smegmatis ist ein Bakterium aus der Gruppe der Mykobakterien. Es handelt sich um stäbchenförmige Bakterien mit einer Länge von 3 bis 5 µm.[1] Es zählt zur Normalflora des Smegmas im menschlichen Genitalbereich, also sowohl im Bereich der weiblichen Vulva und der Klitorisvorhaut, Präputium clitoridis, als auch beim Mann unter dem Praeputium penis. Auch in Bodenproben wurde es häufig gefunden.[2] Es ist nur in seltenen Fällen pathogen[3] und zählt zu den sogenannten nichttuberkulösen Mykobakterien (MOTT). Mycobacterium smegmatis zählt hier zu den schnellwachsenden Mykobakterien, die auf agarhaltigen Nährmedien schon innerhalb einer Woche gut sichtbare Kolonien bilden. Deshalb gilt es auch als Modellorganismus für Mykobakterien und wird oft in Labors für Stoffwechseluntersuchungen verwendet.[4] Die elektronenmikroskopische Charakterisierung erfolgte unter Einsatz der ...
TY - JOUR. T1 - Rapidly growing mycobacteria in TB/HIV co-infection: a report of two cases focusing on difficulties in diagnosis and management.. AU - Bonura, Celestino. AU - Giammanco, Anna. AU - Cala, Cinzia. AU - Di Carlo, Paola. AU - Mammina, Caterina. AU - Fasciana, Teresa Maria Assunta. PY - 2012. Y1 - 2012. N2 - Recent reports indicate an increase in rates of infection and disease due to rapidly growing mycobacteria (RGM) in patients with pre-existing chronic lung disease. Studies have described difficulties in correctly identifying closely related species, even when proper methodologies are adopted, and several different gene targets have been proposed. We describe two cases of RGM infection in a 29-year-old HIV-1 positive Congolese man and a 19-year-old HIV-1 positive Liberian woman, respectively, both with bronchiectasis due to previous Mycobacterium tuberculosis (MTB) infection. Mycobacterium porcinum and Mycobacterium bolletii were identified in bronchoalveolar lavage fluid and ...
Bacteria have the ability to adapt to different growth conditions and to survive in various environments. They have also the capacity to enter into dormant states and some bacteria form spores when exposed to stresses such as starvation and oxygen deprivation. Sporulation has been demonstrated in a number of different bacteria but Mycobacterium spp. have been considered to be non-sporulating bacteria. We recently provided evidence that Mycobacterium marinum and likely also Mycobacterium bovis bacillus Calmette-Gu,rin can form spores. Mycobacterial spores were detected in old cultures and our findings suggest that sporulation might be an adaptation of lifestyle for mycobacteria under stress. Here we will discuss our current understanding of growth, cell division, and sporulation in mycobacteria.. ...
Background: Rhomboids, proteins that are conserved in all life kingdoms, are among the novel genes likely to encode roles in the pathogenesis of mycobacteria. While rhomboids have various specific functions across species, their roles in mycobacteria are not clearly defined. Whereas the insertions, deletions (inDels), point mutations and novel bifurcations have been identified among some mycobacterial rhomboids, their distribution and possible effect on mycobacterial rhomboid function has not been studied. The objective of this study was to functionally characterize additional rhomboid encoding genes from mycobacteria particularly those with InDels, point mutations and novel bifurcations, using bioinformatics and genetic approaches in Providencia stuartii. Methods: This was a laboratory-based experimental study with 56 mycobacterial isolates, from which rhomboid genes were PCR-amplified and cloned. Bioinformatics tools were applied to identify, retrieve and analyze rhomboid genes for ...
Eighteen isolates of a nonchromogenic, slowly growing, non-tuberculous species of the genus Mycobacterium were cultured from respiratory specimens obtained over the last eight years from 17 patients in the Netherlands. These isolates were grouped because they revealed a unique 16S rRNA gene sequence and were related to Mycobacterium xenopi. None of the 17 patients met the American Thoracic Society diagnostic criteria for non-tuberculous mycobacterial disease, which distinguishes the novel isolates from the related species, M. xenopi. A polyphasic taxonomic approach, including identification by biochemical and phenotypical analysis, hsp65 gene sequencing and PCR restriction enzyme pattern analysis, and sequence analyses of the rpoB gene and 16S23S internal transcribed spacer supported the separate species status of the novel isolates. The name Mycobacterium noviomagense sp. nov. is proposed for the novel strains. The type strain is NLA000500338T (=DSM 45145T=CIP 109766T). A more distinctive ...
The virulence of different isolates of Mycobacterium has been associated with two morphologically distinguishable colonial variants: opaque (SmOp) and transparent (SmTr). in this report we used an in vitro assay to compare macrophage (Mphi) responses to SmOp and SmTr Mycobacterium fortuitum variants, taking advantage of the fact that these variants were derived from the same isolate. Cells preactivated or not with gamma interferon (IFN-gamma) were infected with SmOp or SmTr M. fortuitum. We showed that SmOp and SmTr induced different levels of nitric oxide (NO) production by IFN-gamma-stimulated Mphi. Indeed, the amount of IFN-gamma-induced NO production by J774 cells was 4.8 to 9.0 times higher by SmOp (23.1 to 37.7 muM) compared to SmTr infection (3.9 to 4.8 muM) (P = 0.0332), indicating that virulent SmTr bacilli restricted NO production. in addition, IFN-gamma-induced NO production by Mphi was higher when correlated with reduction of only avirulent SmOp bacillus viability. SNAP ...
Despite the considerable knowledge of bacterial high-molecular-weight (HMW) polycyclic aromatic hydrocarbon (PAH) metabolism, the key enzyme(s) and its pleiotropic and epistatic behavior(s) responsible for low-molecular-weight (LMW) PAHs in HMW PAH-metabolic networks remain poorly understood. In this study, a phenotype-based strategy, coupled with a spray plate method, selected a Mycobacterium vanbaalenii PYR-1 mutant (6G11) that degrades HMW PAHs but not LMW PAHs. Sequence analysis determined that the mutant was defective in pdoA2, encoding an aromatic ring-hydroxylating oxygenase (RHO). A series of metabolic comparisons using high-performance liquid chromatography (HPLC) analysis revealed that the mutant had a lower rate of degradation of fluorene, anthracene, and pyrene. Unlike the wild type, the mutant did not produce a color change in culture media containing fluorene, phenanthrene, and fluoranthene. An Escherichia coli expression experiment confirmed the ability of the Pdo system to oxidize
Scherr N., Honnappa S., Kunz G., Mueller P., Jayachandran R., Winkler F., Pieters J., Steinmetz M.O.. The pathogenicity of mycobacteria such as Mycobacterium tuberculosis is closely associated with their capacity to survive within host macrophages. A crucial virulence factor for intracellular mycobacterial survival is protein kinase G (PknG), a eukaryotic-like serine/threonine protein kinase expressed by pathogenic mycobacteria that blocks the intracellular degradation of mycobacteria in lysosomes. Inhibition of PknG with the highly selective low-molecular-weight inhibitor AX20017 results in mycobacterial transfer to lysosomes and killing of the mycobacteria. Here, we report the 2.4 A x-ray crystal structure of PknG in complex with AX20017. The unique multidomain topology of PknG reveals a central kinase domain that is flanked by N- and C-terminal rubredoxin and tetratrico-peptide repeat domains, respectively. Directed mutagenesis suggests that the rubredoxin domain functions as a regulator of ...
We describe what we believe to be the first documented case of Mycobacterium goodii infection in Europe. It is also the second documented report of a pacemaker pocket surgical site infection caused by M. goodii. Although rarely involved in such infections, rapidly growing mycobacteria should be recognized during conventional bacteriological investigations and further identified by molecular tools to provide adequate therapy. In the present case, antimicrobial therapy with doxycycline without removal of the pacemaker was successful.
On July 9, 2014, Aeras and the Max Planck Institute for Infection Biology convened a workshop entitled Whole Mycobacteria Cell Vaccines for Tuberculosis at the Max Planck Institute for Infection Biology on the grounds of the Charité Hospital in Berlin, Germany, close to the laboratory where, in 1882, Robert Koch first identified Mycobacterium tuberculosis (Mtb) as the pathogen responsible for tuberculosis (TB). The purpose of the meeting was to discuss progress in the development of TB vaccines based on whole mycobacteria cells. Live whole cell TB vaccines discussed at this meeting were derived from Mtb itself, from Bacille Calmette-Guérin (BCG), the only licensed vaccine against TB, which was genetically modified to reduce pathogenicity and increase immunogenicity, or from commensal non-tuberculous mycobacteria. Inactivated whole cell TB and non-tuberculous mycobacterial vaccines, intended as immunotherapy or as safer immunization alternatives for HIV+ individuals, also were discussed. ...
Molecular cloning and expression of genes encoding a novel dioxygenase involved in low- and high-molecular-weight polycyclic aromatic hydrocarbon degradation in Mycobacterium vanbaalenii PYR-1 ...
Isolation and differentiation of various species of mycobacteria are predominantly based on conventional, cultural and biochemical tests. Among the non-tuberculous mycobacteria, these tests are unable to differentiate M. scrofulaceum from M. avium-intracellulare (MAI) because of their identical biochemical characteristics. For this reason, one hundred mycobacterial strains suspected to be M. ...
A 25-year old male patient with cystic fibrosis has developed progressive disease and his medical team is considering referral for lung transplantation. The patient has a history of pancreatic insufficiency and well controlled diabetes. He has been infected with Pseudomonas aeruginosa and Methicillin Sensitive Staphylococcus aureus. Some of his recent mycobacterial cultures have had low growth of Mycobacterium abscessus. Is this an appropriate candidate for lung transplantation?
Galactosamine was found consistently as a minor component of the envelope of five species of slow-growing mycobacteria, including all the major human pathogens, but not three rapid-growing species. The amino sugar was a component of the arabinogalactan of the cell wall skeleton, and occurred at the level of about one residue per arabinogalactan chain. Its amino group was in the free, un-N-acetylated state. Examination of oligosaccharides released by partial acid hydrolysis of arabinogalactan by fast atom bombardment-MS and gas chromatography-MS identified a series of oligoarabinans, each possessing one GalN unit, linked to position 2 of arabinose. It is proposed that the GalN residues occur as stub branches of 1 → 5-linked arabinose chains in the arabinogalactan. Possible functions of GalN are discussed.. ...
Background: The Mycobacterium tuberculosis complex causes a variety of diseases; in bovine, the common pathogen is M. bovis which is considered zoonotic. A separate group of mycobacteria, much less known, is non-tuberculous mycobacteria (NTM) which are also infectious for animals and humans. ...
Mycobacterium neoaurum is a soil saprophyte and obligate aerobic bacterium. This group of mycobacterium is relatively fast-growing. They form colonies on nutrient agar at 37 masculineC within 3 - 4 days. In natural soil habitats, bioavailability of iron is limited. To facilitate iron uptake, most mycobacteria produce siderophores. One example is exochelin, which is extracellular and water-soluble. In this report, the production of exochelin in M. neoaurum was induced in iron-deficiency, but repressed under ironsufficiency growth conditions. It is however not induced under zinc-deficiency growth conditions. The growth of this mycobacterium was correlated with exochelin secretion under iron-deficiency culture conditions. When M. neoaurum was grown in defined medium containing 0.04 microg Fe(III)/mL (final concentration), the production of exochelin reached a maximum and the corresponding cell growth was comparable to that under iron-sufficiency conditions. In this study, exochelin was purified ...
Microorganisms must maintain equilibrium and intracellular availability of ions for growth and persistence in a range of environments, either in the face of scarce resources or excesses, whereby they must buffer, exclude or export these ions preventing accumulation to harmful levels. Ion homeostasis is essential for energy generation, metabolism, regulation of internal pH and osmotic homeostasis. Mycobacteria are part of the native microflora found in soils and aquatic environments and harbour an extensive repertoire of uptake and efflux and secretion pathways to modulate ions and metabolites including, sodium, potassium, calcium, magnesium, iron, nickel, manganese, zinc, copper and cobalt. There remains a paucity of information regarding ion homeostasis networks and pathways in mycobacteria. The overarching aim of this thesis was to characterise ion homeostasis and energetics in the saprophyte Mycobacterium smegmatis, under normoxia and hypoxia, under ion chelation and deficiency, with ...
Environmental opportunistic mycobacteria, including Mycobacterium avium, M. terrae, and the new species M. immunogenum, have been implicated in outbreaks of hypersensitivity pneumonitis or respiratory problems in a wide variety of settings. One common feature of the outbreaks has been exposure to aerosols. Aerosols have been generated from metalworking fluid during machining and grinding operations as well as from indoor swimming pools, hot tubs, and water-damaged buildings. Environmental opportunistic mycobacteria are present in drinking water, resistant to disinfection, able to provoke inflammatory reactions, and readily aerosolized. In all outbreaks, the water sources of the aerosols were disinfected. Disinfection may select for the predominance and growth of mycobacteria. Therefore, mycobacteria may be responsible, in part, for many outbreaks of hypersensitivity pneumonitis and other respiratory problems in the workplace and home ...
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Title: The Common Mycobacterial Antigens and their Importance in the Treatment of Disease. VOLUME: 15 ISSUE: 11. Author(s):John Stanford, Cynthia Stanford, Gerard Stansby, Oscar Bottasso, Georges Bahr and John Grange. Affiliation:Centre for Infectious Diseases and International Medicine, Windeyer Institute of Medical Sciences, University College London, 46 Cleveland Street, London W1T 4JF, UK.. Keywords:Common antigens, heat shock/stress proteins, immunotherapy, actinomycetales, Mycobacterium vaccae. Abstract: The mycobacteria are one of a number of genera making up the aerobic Actinomycetales. Their antigens demonstrable by immuno-precipitation methods can be divided into four groups. The group i antigens, common to all mycobacterial species, cross-react with their counterparts in animal cells, largely derived from mitochondria. Notable amongst these antigens are the heat-shock, or stress, proteins and possibly bacterial sugars. Tests of cell-mediated immunity show that people can be separated ...