Salgado, M; Herthnek, D; Bölske, G; Leiva, S; Kruze, J
The aim of this study was to search for Mycobacterium avium subsp. paratuberculosis (Map) infection in a free-ranging wild animal species in a region where Johnes's disease has yet to be reported and to classify Map isolates using a genomic typing method. Fecal samples were obtained from 501 wild guanacos (Lama guanicoe) from Tierra del Fuego Island, Chile, in August 2006. Samples were cultured using Herrold's egg yolk medium with and without mycobactin J. After 9 mo of incubation, suspected Map colonies showing mycobactin dependence were confirmed by real-time polymerase chain reaction (PCR) based on IS900 and F57. Isolates were further tested using IS1311 PCR with restriction endonuclease analysis in order to type the guanaco Map strains. Twenty-one of 501 (4.2%) animals were fecal culture-positive for Map; identity was confirmed by real-time PCR and isolates were classified as cattle-type. Most culture-positive animals were located in four contiguous geographic areas, and the infection was most commonly found among adult animals. Prevalence was higher in females (5.9%) than males (3.1%) but the difference was not statistically significant. This represents the first isolation of Map from a free-ranging wildlife species in Chile. It expands the geographic range of paratuberculosis and the diversity of wildlife species that can become infected with Map.
García, Pamela K.; Nieto, Luisa Maria; van Soolingen, Dick
Previous evaluations of the molecular GenoType tests have promoted their use to detect resistance to first- and second-line antituberculosis drugs in different geographical regions. However, there are known geographic variations in the mutations associated with drug resistance in Mycobacterium tuberculosis, and especially in South America, there is a paucity of information regarding the frequencies and types of mutations associated with resistance to first- and second-line antituberculosis drugs. We therefore evaluated the performance of the GenoType kits in this region by testing 228 M. tuberculosis isolates in Colombia, including 134 resistant and 94 pansusceptible strains. Overall, the sensitivity and specificity of the GenoType MTBDRplus test ranged from 92 to 96% and 97 to 100%, respectively; the agreement index was optimal (Cohen's kappa, >0.8). The sensitivity of the GenoType MTBDRsl test ranged from 84 to 100% and the specificity from 88 to 100%. The most common mutations were katG S315T1, rpoB S531L, embB M306V, gyrA D94G, and rrs A1401G. Our results reflect the utility of the GenoType tests in Colombia; however, as some discordance still exists between the conventional and molecular approaches in resistance testing, we adhere to the recommendation that the GenoType tests serve as early guides for therapy, followed by phenotypic drug susceptibility testing for all cases. PMID:23658272
Nieto, Luisa Maria; Rozo, Juan C.; Forero, Liliana; van Soolingen, Dick
Using spoligotyping, we identified 13 genotypes and 17 orphan types among 160 Mycobacterium tuberculosis isolates from patients in Valle del Cauca, Colombia. The Beijing genotype represented 15.6% of the isolates and was correlated with multidrug-resistant tuberculosis, female sex of the patients, and residence in Buenaventura and may represent a new public health threat. PMID:21762581
Saad, Mustafa M; Alshukairi, Abeer N; Qutub, Mohammed O; Elkhizzi, Noura A; Hilluru, Haris M; Omrani, Ali S
Mycobacterium riyadhense is a newly described slowly growing, non-tuberculous mycobacterium species. We describe 2 new cases of Mycobacterium riyadhense infections presenting with extra-pulmonary involvement, and reviewed all previously reported cases in the literature. We also describe the spectrum of the disease and explore treatment options based on the experience with the current and previously reported cases.
Cattle were inoculated with Mycobacterium bovis, Mycobacterium tuberculosis, or Mycobacterium kansasii to compare antigen-specific immune responses to varied patterns of mycobacterial disease. Disease expression ranged from colonization with associated pathology (M. bovis), colonization without path...
María Ibáñez Cabanell, José
Son muchos los escenarios astrofísicos en que los procesos hidrodinámicos juegan un papel clave. En la complejidad que encierra la descripción de dichos procesos destaca el de la correcta simulación de flujos complejos donde la presencia de ondas de choque fuertes que, eventualmente, interaccionan entre ellas o también la presencia de inestabilidades (Kelvin-Helmholtz, Rayleigh-Taylor, etc.) suponen un verdadero desafío numérico. Los códigos hidrodinámicos basados en la solución de un problema de valores iniciales discontinuo (problema de Riemann) son, en la actualidad, los más robustos en el campo de la dinámica de fluidos computacional. En esta charla se dará un resumen de los fundamentos de dichas técnicas numéricas (esquemas de alta resolución de captura de choques) y se ilustrará su potencialidad mostrando una amplia gama de resultados en diferentes aplicaciones astrofísicas.
Cassetty, Christopher T; Sanchez, Miguel
A 49-year-old man presented with nodules on his right hand after a history of Mycobacterium marinum infection recently treated with rifampin and clarithromycin. The patient has an aquarium with Betta fish (Siamese fighting fish).
Muñoz Mendoza, Marta; Juan, Lucía de; Menéndez, Santiago; Ocampo, Antón; Mourelo, Jorge; Sáez, José L; Domínguez, Lucas; Gortázar, Christian; García Marín, Juan F; Balseiro, Ana
Tuberculosis was diagnosed in three flocks of sheep in Galicia, Spain, in 2009 and 2010. Two flocks were infected with Mycobacterium bovis and one flock was infected with Mycobacterium caprae. Infection was confirmed by the comparative intradermal tuberculin test, bacteriology, molecular analysis and histopathology. Sheep have the potential to act as a reservoir for tuberculosis. Copyright © 2011 Elsevier Ltd. All rights reserved.
van der Werf, Tjip S.; Stienstra, Ymkje; Johnson, R. Christian; Phillips, Richard; Adjei, Ohene; Fleischer, Bernhard; Wansbrough-Jones, Mark H.; Johnson, Paul D. R.; Portaels, Françoise; van der Graaf, Winette T. A.; Asiedu, Kingsley
Mycobacterium ulcerans disease (Buruli ulcer) is an important health problem in several west African countries. It is prevalent in scattered foci around the world, predominantly in riverine areas with a humid, hot climate. We review the epidemiology, bacteriology, transmission, immunology, pathology, diagnosis and treatment of infections. M. ulcerans is an ubiquitous micro-organism and is harboured by fish, snails, and water insects. The mode of transmission is unknown. Lesions are most common on exposed parts of the body, particularly on the limbs. Spontaneous healing may occur. Many patients in endemic areas present late with advanced, severe lesions. BCG vaccination yields a limited, relatively short-lived, immune protection. Recommended treatment consists of surgical debridement, followed by skin grafting if necessary. Many patients have functional limitations after healing. Better understanding of disease transmission and pathogenesis is needed for improved control and prevention of Buruli ulcer. PMID:16283056
Warner, Digby F.
Metabolism underpins the physiology and pathogenesis of Mycobacterium tuberculosis. However, although experimental mycobacteriology has provided key insights into the metabolic pathways that are essential for survival and pathogenesis, determining the metabolic status of bacilli during different stages of infection and in different cellular compartments remains challenging. Recent advances—in particular, the development of systems biology tools such as metabolomics—have enabled key insights into the biochemical state of M. tuberculosis in experimental models of infection. In addition, their use to elucidate mechanisms of action of new and existing antituberculosis drugs is critical for the development of improved interventions to counter tuberculosis. This review provides a broad summary of mycobacterial metabolism, highlighting the adaptation of M. tuberculosis as specialist human pathogen, and discusses recent insights into the strategies used by the host and infecting bacillus to influence the outcomes of the host–pathogen interaction through modulation of metabolic functions. PMID:25502746
Jackson, Paige N.; Embry, Ella K.; Johnson, Christa O.; Watson, Tiara L.; Weast, Sayre K.; DeGraw, Caroline J.; Douglas, Jessica R.; Sellers, J. Michael; D’Angelo, William A.
Waterfoul is a newly isolated temperate siphovirus of Mycobacterium smegmatis mc2155. It was identified as a member of the K5 cluster of Mycobacterium phages and has a 61,248-bp genome with 95 predicted genes. PMID:27856585
Prodinger, Wolfgang M; Indra, Alexandra; Koksalan, Orhan K; Kilicaslan, Zeki; Richter, Elvira
Mycobacterium caprae, a member of the Mycobacterium tuberculosis complex, causes tuberculosis (TB) in man and animals. Some features distinguish M. caprae from its epidemiological twin, Mycobacterium bovis: M. caprae is evolutionarily older, accounts for a smaller burden of zoonotic TB and is not globally distributed, but primarily restricted to European countries. M. caprae occurs only in a low proportion of human TB cases and this proportion may even decrease, if progress toward eradication of animal TB in Europe continues. So why bother, if M. caprae is not an enigma for diagnostic TB tests and if resistance against first-line drugs is a rarity with M. caprae? This 'European' pathogen of zoonotic TB asks interesting questions regarding the definition of a species. The latter, seemingly only an academic question, particularly requires and challenges the collaboration between human and veterinary medicine.
Nogueira, Christiane Lourenço; Whipps, Christopher M.; Matsumoto, Cristianne Kayoko; Chimara, Erica; Droz, Sara; Tortoli, Enrico; de Freitas, Denise; Cnockaert, Margo; Palomino, Juan Carlos; Martin, Anandi; Vandamme, Peter
Five isolates of non-pigmented, rapidly growing mycobacteria were isolated from three patients and, in an earlier study, from zebrafish. Phenotypic and molecular tests confirmed that these isolates belong to the Mycobacterium chelonae–Mycobacterium abscessus group, but they could not be confidently assigned to any known species of this group. Phenotypic analysis and biochemical tests were not helpful for distinguishing these isolates from other members of the M. chelonae–M. abscessus group. The isolates presented higher drug resistance in comparison with other members of the group, showing susceptibility only to clarithromycin. The five isolates showed a unique PCR restriction analysis pattern of the hsp65 gene, 100 % similarity in 16S rRNA gene and hsp65 sequences and 1–2 nt differences in rpoB and internal transcribed spacer (ITS) sequences. Phylogenetic analysis of a concatenated dataset including 16S rRNA gene, hsp65, and rpoB sequences from type strains of more closely related species placed the five isolates together, as a distinct lineage from previously described species, suggesting a sister relationship to a group consisting of M. chelonae, Mycobacterium salmoniphilum, Mycobacterium franklinii and Mycobacterium immunogenum. DNA–DNA hybridization values >70 % confirmed that the five isolates belong to the same species, while values < 70 % between one of the isolates and the type strains of M. chelonae and M. abscessus confirmed that the isolates belong to a distinct species. The polyphasic characterization of these isolates, supported by DNA–DNA hybridization results, demonstrated that they share characteristics with M. chelonae–M. abscessus members, but constitute a different species, for which the name Mycobacterium saopaulense sp. nov. is proposed. The type strain is EPM 10906T ( = CCUG 66554T = LMG 28586T = INCQS 0733T). PMID:26358475
Sechi, Leonardo A.; Duprè, Ilaria; Leori, Guido; Fadda, Giovanni; Zanetti, Stefania
Amplification of a specific, 500-bp fragment from Mycobacterium bovis isolates and use of the fragment to differentiate between Mycobacterium tuberculosis and M. bovis was previously reported (J. G. Rodriguez, G. A. Meja, P. Del Portillo, M. E. Patarroyo, and L. A. Murillo, Microbiology 141:2131–2138, 1995). In the present study, 30 M. bovis isolates from Sardinian cattle were examined for the presence of this 500-bp fragment; 4 of the 30 isolates lacked the fragment. This result indicates that identification of M. bovis strains by amplification of the 500-bp sequence may lead to false-negative results. PMID:11015414
Kethireddy, Shravan; Light, R Bruce; Mirzanejad, Yazdan; Maki, Dennis; Arabi, Yaseen; Lapinsky, Stephen; Simon, David; Kumar, Aseem; Parrillo, Joseph E; Kumar, Anand
Septic shock due to Mycobacterium tuberculosis (MTB) is an uncommon but well-recognized clinical syndrome. The objective of this study was to describe the unique clinical characteristics, epidemiologic risk factors, and covariates of survival of patients with MTB septic shock in comparison with other bacterial septic shock. A retrospective nested cohort study was conducted of patients given a diagnosis of MTB septic shock derived from a trinational, 8,670-patient database of patients with septic shock between 1996 and 2007. In the database, 53 patients had been given a diagnosis of MTB shock compared with 5,419 with septic shock associated with isolation of more common bacterial pathogens. Patients with MTB and other bacterial septic shock had in-hospital mortality rates of 79.2% and 49.7%, respectively (P < .0001). Of the cases of MTB shock, all but five patients had recognized respiratory tract involvement. Fifty-five percent of patients (29 of 53) were documented (by direct culture or stain) as having disseminated extrapulmonary involvement. Inappropriate and appropriate initial empirical therapy was delivered in 28 patients (52.8%) and 25 patients (47.2%); survival was 7.1% and 36.0%, respectively (P = .0114). Ten patients (18.9%) did not receive anti-MTB therapy; all died. The median time to appropriate antimicrobial therapy for MTB septic shock was 31.0 h (interquartile range, 18.9-71.9 h). Only 11 patients received anti-MTB therapy within 24 h of documentation of hypotension; six of these (54.5%) survived. Only one of 21 patients (4.8%) who started anti-MTB therapy after 24 h survived (P = .0003 vs < 24 h). Survival differences between these time intervals are not significantly different from those seen with bacterial septic shock due to more common bacterial pathogens. MTB septic shock behaves similarly to bacterial septic shock. As with bacterial septic shock, early appropriate antimicrobial therapy appears to improve mortality.
Acosta, Fermín; Chernyaeva, Ekatherina; Mendoza, Libardo; Sambrano, Dilcia; Correa, Ricardo; Rotkevich, Mikhail; Tarté, Miroslava; Hernández, Humberto; Velazco, Bredio; de Escobar, Cecilia; de Waard, Jacobus H.
Panama remains free of zoonotic tuberculosis caused by Mycobacterium bovis. However, DNA fingerprinting of 7 M. bovis isolates from a 2013 bovine tuberculosis outbreak indicated minimal homology with strains previously circulating in Panama. M. bovis dispersion into Panama highlights the need for enhanced genotype testing to track zoonotic infections. PMID:25988479
Ofer, Naomi; Wishkautzan, Marina; Meijler, Michael; Wang, Ying; Speer, Alexander; Niederweis, Michael; Gur, Eyal
Mycobacterium smegmatis is a commonly used mycobacterial model system. Here, we show that M. smegmatis protects itself against elevated salinity by synthesizing ectoine and hydroxyectoine and characterize the phenotype of a nonproducing mutant. This is the first analysis of M. smegmatis halotolerance and of the molecular mechanism that supports it.
Barclay, R; Ewing, D F; Ratledge, C
Methods were devised to purify the cell-associated, iron-binding compounds known as mycobactins from the closely related species Mycobacterium avium, Mycobacterium intracellulare, and Mycobacterium scrofulaceum (i.e., the MAIS complex of organisms). The mycobactins from these three species showed a structure that is common to the mycobactins from all the mycobacteria examined to date. However, these mycobactins were unique in that they had more than one alkyl chain. The M. scrofulaceum mycobactins differed from other MAIS mycobactins by a shift in the position of the double bond in the R1 alkyl chain. Traces of other mycobactin types were observed in ethanol extracts of the three species, and examination of the chromatographic properties of these mycobactins showed that each species produced five mycobactin types. Each mycobactin could be subdivided further by the length of its R1 alkyl chain. No differences in the production of these novel mycobactin were observed among species. Mycobactins from three strains of Mycobacterium paratuberculosis and two wood pigeon strains of Mycobacterium avium which had lost their original growth requirements for mycobactin after repeated subculturing in laboratory growth media were examined by thin-layer chromatography and high-pressure liquid chromatography. Each organism produced a mycobactin with similar chromatographic properties to those synthesized by MAIS organisms. M. paratuberculosis NADC 18 produced at least two components in our laboratory, and nuclear magnetic resonance analysis of the major component showed this mycobactin to be identical to that produced by M. intracellulare M12. However, a sample of mycobactin J isolated by Merkal and McCullough (Curr. Microbiol. 7:333-335, 1982) from M. paratuberculosis NADC 18 was different from our isolates and appeared to correspond to a minor mycobactin component we had seen by thin-layer chromatography. No reason for this difference could be evinced. Our findings indicate that
Inderlied, C B; Kemper, C A; Bermudez, L E
Mycobacterium avium complex (MAC) disease emerged early in the epidemic of AIDS as one of the common opportunistic infections afflicting human immunodeficiency virus-infected patients. However, only over the past few years has a consensus developed about its significance to the morbidity and mortality of AIDS. M. avium was well known to mycobacteriologists decades before AIDS, and the MAC was known to cause disease, albeit uncommon, in humans and animals. The early interest in the MAC provided a basis for an explosion of studies over the past 10 years largely in response to the role of the MAC in AIDS opportunistic infection. Molecular techniques have been applied to the epidemiology of MAC disease as well as to a better understanding of the genetics of antimicrobial resistance. The interaction of the MAC with the immune system is complex, and putative MAC virulence factors appear to have a direct effect on the components of cellular immunity, including the regulation of cytokine expression and function. There now is compelling evidence that disseminated MAC disease in humans contributes to both a decrease in the quality of life and survival. Disseminated disease most commonly develops late in the course of AIDS as the CD4 cells are depleted below a critical threshold, but new therapies for prophylaxis and treatment offer considerable promise. These new therapeutic modalities are likely to be useful in the treatment of other forms of MAC disease in patients without AIDS. The laboratory diagnosis of MAC disease has focused on the detection of mycobacteria in the blood and tissues, and although the existing methods are largely adequate, there is need for improvement. Indeed, the successful treatment of MAC disease clearly will require an early and rapid detection of the MAC in clinical specimens long before the establishment of the characteristic overwhelming infection of bone marrow, liver, spleen, and other tissue. Also, a standard method of susceptibility testing
Mullis, S N; Falkinham, J O
Measure adherence and biofilm formation by cells of Mycobacterium avium, Mycobacterium intracellulare and Mycobacterium abscessus on common household plumbing materials namely stainless steel, glass, zinc-galvanized steel, copper and polyvinyl chloride (PVC). Coupons in a CDC biofilm reactor were exposed to cell suspensions containing 10(5) NTM colony forming units (CFU) per ml and adherence measured for 6 h. Biofilm formation (increased numbers of adherent CFU) was measured weekly to 21 days in the absence of substantial numbers of suspended mycobacterial cells. Adherence was rapid and substantial with 2000-15 000 CFU cm(-2) adhering within 1-6 h at room temperature. Biofilm numbers reached as high as 10(7) CFU cm(-2) . Biofilm-grown cells of Myco. avium were more adherent compared with suspension-grown cells. Mycobacterium avium, Myco. intracellulare and Myco. abscessus readily adhered and formed biofilms on all types of plumbing materials. Factors influencing adherence and biofilm formation were species, plumbing material and prior growth. © 2013 The Society for Applied Microbiology.
Mycobacterium tuberculosis and Mycobacterium bovis are responsible for tuberculosis in humans or animals, respectively. Both species are closely related and belong to the Mycobacterium tuberculosis complex (MTC). M. tuberculosis is the most ancient species from which M. bovis and the other members o...
Moutsoglou, Daphne M; Merritt, Frank; Cumbler, Ethan
Mycobacterium chimaera, a member of the Mycobacterium avium complex, is a slow-growing, nontuberculous mycobacterium associated with outbreaks in cardiac-surgery patients supported on heart-lung machines. We report a case of an elderly woman on chronic prednisone who presented with a six-month history of worsening chronic back pain, recurrent low-grade fevers, and weight loss. Imaging identified multilevel vertebral osteomyelitis and lumbar soft-tissue abscess. Abscess culture identified M. chimaera.
Ben Salah, Iskandar; Cayrou, Caroline; Raoult, Didier; Drancourt, Michel
An rpoB sequence-based evaluation of 100 Mycobacterium avium complex (MAC) clinical isolates led to the identification of five respiratory tract isolates that were potential representatives of three novel MAC species. Distinctive phenotypic features of isolates 62863 and 5356591(T) included a pseudomycelium morphology and both esterase and acid phosphatase activities. These two isolates exhibited sequence similarities of 99.8 % for the 16S rRNA gene, 86.3 and 86.1 % for 16S-23S rRNA gene internal transcribed spacer (ITS-1) sequence, 96.7 and 97.8 % for rpoB and 97.6 and 97.4 % for hsp65, respectively, with the type strain of Mycobacterium chimaera, the most closely related species. Isolates 3256799 and 5351974(T) lacked alpha-mannosidase and beta-glucosidase activities. They exhibited sequence similarities of 99.6 % for the 16S rRNA gene, 90.1 and 90.4 % for ITS-1, 97.8 % for rpoB and 98.0 and 98.1 % for hsp65, respectively, with the type strain of M. chimaera, the most closely related species. Isolate 4355387(T) lacked urease and alpha-glucosidase activities, but it exhibited valine arylamidase, cystine arylamidase and acid phosphatase activities. It had sequence similarities of 99.3 % for the 16S rRNA gene, 51.8 % for ITS-1, 97.1 % for rpoB and 97.8 % for hsp65 with the type strain of Mycobacterium colombiense, the most closely related species. A phylogenetic tree based on concatenated 16S rRNA gene, ITS-1, rpoB and hsp65 sequences showed the uniqueness of these five isolates as representatives of three novel species, with bootstrap values >/=95 % in all nodes. On the basis of these phenotypic and genetic characteristics, these five isolates are proposed as representatives of three novel MAC species: Mycobacterium marseillense sp. nov., with strain 5356591(T) (=CCUG 56325(T) =CIP 109828(T) =CSUR P30(T)) as the type strain; Mycobacterium timonense sp. nov., with strain 5351974(T) (=CCUG 56329(T) =CIP 109830(T) =CSUR P32(T)) as the type strain; and Mycobacterium
García-Martos, Pedro; García-Agudo, Lidia; González-Moya, Enrique; Galán, Fátima; Rodríguez-Iglesias, Manuel
Mycobacterium simiae is a slow-growing photochromogenic environmental mycobacterium, first described in 1965. Rarely associated with human infections, possibly due to its limited pathogenicity, it mainly produces lung infection in immunocompetent elderly patients with underlying lung disease, and in disseminated infections in immunosuppressed young patients with AIDS. A microbiological culture is needed to confirm the clinical suspicion, and genetic sequencing techniques are essential to correctly identify the species. Treating M. simiae infections is complicated, owing to the multiple resistance to tuberculous drugs and the lack of correlation between in vitro susceptibility data and in vivo response. Proper treatment is yet to be defined, but must include clarithromycin combined with other antimicrobials such as moxifloxacin and cotrimoxazole. It is possible that M. simiae infections are undiagnosed.
Bouam, Amar; Robert, Catherine; Levasseur, Anthony
ABSTRACT Mycobacterium colombiense is a rapidly growing mycobacterium initially isolated from the blood of an HIV-positive patient in Colombia. Its 5,854,893-bp draft genome exhibits a G+C content of 67.64%, 5,233 protein-coding genes, and 54 predicted RNA genes. PMID:28385843
Tortoli, Enrico; Bartoloni, Alessandro; Erba, Maria Luigia; Levrè, Egle; Lombardi, Natalia; Mantella, Antonia; Mecocci, Lorenzo
Three cases of human disease due to Mycobacterium lentiflavum are reported. In the first, the mycobacterium was responsible for chronic pulmonary disease in an elderly woman; in the second, it gave rise to cervical lymphadenitis in a child; and in the third, it caused a liver abscess in a young AIDS patient. PMID:11826009
Barksdale, L; Kim, K S
Evidence is presented which suggests that certain key markers of lepra bacilli reside collectively in Proprionibacterium acnes, Corynebacterium tuberculostearicum and Mycobacterium leprae. The unrestricted replication of Mycobacterium leprae depends most probably upon the presence of an immune-deficiency-inducing viral agent or possibly on the combined effects of the organisms considered.
Barry, Maureen; Taylor, Judith; Woods, Paul
A domestic shorthair cat was presented for lethargy and ataxia. Clinical findings included an abdominal mass, lumbosacral pain, ataxia. Aspirates from the liver and lymph nodes revealed intracellular, negative-staining rods. Treatment for presumptive mycobacterium infection was unsuccessful and the cat was euthanized. Disseminated Mycobacterium avium was confirmed on culture. PMID:12001504
Benton, J; Karkanevatos, A
Mycobacterium marinum is an atypical mycobacterium found in both salt and fresh water. It occasionally causes soft tissue infections after minor trauma, principally affecting the limbs. A 17-year-old male aquarium worker presented with preseptal cellulitis of his right eye, after attempting to lance a hordeolum some days previously. The condition failed to respond to antibiotics and a necrotic area developed, which subsequently required debridement. Histology of the debrided area demonstrated granulomatous inflammation which when considered with his occupation led to the diagnosis of Mycobacterium marinum--'fish-tank granuloma'. A Medline search did not demonstrate any previous cases of Mycobacterium marinum infection occurring peri-orbitally. The current literature regarding diagnosis and management is reviewed. Although infection with Mycobacterium marinum is rare in the general population, this case demonstrates the importance of considering the diagnosis when dealing with patients frequently exposed to fresh or salt water.
Taxonomic variation in the Mycobacterium fortuitum third biovariant complex: description of Mycobacterium boenickei sp. nov., Mycobacterium houstonense sp. nov., Mycobacterium neworleansense sp. nov. and Mycobacterium brisbanense sp. nov. and recognition of Mycobacterium porcinum from human clinical isolates.
Schinsky, Mark F; Morey, Roger E; Steigerwalt, Arnold G; Douglas, Michael P; Wilson, Rebecca W; Floyd, Margaret M; Butler, W Ray; Daneshvar, Maryam I; Brown-Elliott, Barbara A; Wallace, Richard J; McNeil, Michael M; Brenner, Don J; Brown, June M
The Mycobacterium fortuitum third biovariant complex (sorbitol-negative and sorbitol-positive) contains unnamed taxa first characterized in 1991. These organisms can cause respiratory infections, a spectrum of soft tissue and skeletal infections, bacteraemia and disseminated disease. To evaluate this group of organisms, clinical reference isolates and the type strains of M. fortuitum third biovariant complex sorbitol-negative (n = 21), M. fortuitum third biovariant complex sorbitol-positive (n = 3), M. fortuitum (n = 3), Mycobacterium peregrinum (pipemidic acid-susceptible) (n = 1), Mycobacterium porcinum (n = 1), Mycobacterium senegalense (n = 2) and Mycobacterium septicum (n = 1) were characterized by using conventional phenotypic (morphological, physiological and antimicrobial susceptibilities), chemotaxonomic (HPLC and cellular fatty acids) and genotypic [RFLP of the rRNA gene (ribotyping), PCR-RFLP of a 439 bp segment of the 65 kDa hsp gene (PCR restriction analysis) and 16S rRNA gene sequence] analysis, DNA G + C content and DNA-DNA relatedness analyses. The results of these studies indicated that the strains comprised M. porcinum (n = 13), M. septicum (n = 1) and four novel closely related genetic groups within the M. fortuitum third biovariant complex: Mycobacterium boenickei sp. nov. (n = 6), Mycobacterium houstonense sp. nov. (n = 2), Mycobacterium neworleansense sp. nov. (n = 1) and Mycobacterium brisbanense sp. nov. (n = 1), with type strains ATCC 49935T (= W5998T = DSM 44677T), ATCC 49403T (= W5198T = DSM 44676T) ATCC 49404T (= W6705T = DSM 44679T) and ATCC 49938T (= W6743T = DSM 44680T), respectively.
Segura, C; Salvadó, M
Re-emergence of infectious diseases caused by mycobacteria as well as the emergence of multiresistant strains of Mycobacterium has promoted the research on the use of beta-lactames in the treatment of such diseases. Mycobacteria produce beta-lactamases: M. tuberculosis produces a wide-spectrum beta-lactamase whose behaviour mimicks those of Gram-negative bacteria. M. kansasii produces also beta-lactamase which can be inhibited by clavulanic acid. An overview on beta-lactamases from both species is reported.
Cremades, H.; Mandrini, C. H.; Schmieder, C.; Crescitelli, M.
The complex formed by active regions 11121 and 11123 (NOAA numbers); approximately located on the solar central meridian on 11 November 2010; was site of emergence of new magnetic dipoles; which produced the destabilization of active and quiescent filaments that were ejected as coronal mass ejections (CMEs) toward Earth. From its perspective; the events are observed by the AIA telescope aboard the Solar Dynamics Observatory (SDO) and the LASCO coronagraphs from the Solar and Heliospheric Observatory (SOHO). For this date the twin STEREO spacecraft were approximately 180º appart; i.e. observing the complex from the corresponding solar limbs and thus with an exceptional view of the CMEs originating there. The amount of events observed from Earth's perspective and from the orthogonal provided by STEREO differs significantly. This reveals deficiencies in current space weather forecasting; by missing alarms when there are no solar observations perpendicular to the Sun-Earth line. FULL TEXT IN SPANISH
Williams, Kerstin J.; Chung, Gavin A. C.; Piddock, Laura J. V.
The modified fluorescence method was used to determine the accumulation of norfloxacin by Mycobacterium aurum A+ and Mycobacterium smegmatis mc2155. By using an exogenous norfloxacin concentration of 10 μg/ml, a steady-state concentration (SSC) of 160 to 180 ng of norfloxacin/mg of cells was obtained for M. aurum, and an SSC of 120 to 140 ng of norfloxacin/mg of cells obtained for M. smegmatis. For both species of mycobacteria, the SSC was achieved within 5 min. The silicon oil method was investigated and gave higher SSCs than the modified fluorescence method. Further studies on the mechanism of norfloxacin accumulation by M. aurum were performed. An increase in the pH of the wash buffer from 7.0 to 9.0 did not significantly affect the final SSC obtained. Accumulation was nonsaturated over a norfloxacin concentration range of 0 to 100 μg/ml, and the proton motive force inhibitor 2,4-dinitrophenol (1 and 2 mM), whether it was added before or after norfloxacin was added, had no effect on the final SSC obtained. 2,4-Dinitrophenol also had no effect on norfloxacin accumulation by M. smegmatis. Furthermore, norfloxacin accumulation by M. aurum was unaffected by the presence of either Tween 80 or subinhibitory concentrations of ethambutol in the growth medium. Therefore, it is proposed that norfloxacin accumulation by mycobacteria occurs by simple, energy-independent diffusion. PMID:9559785
Okada, Masaji; Shirakawa, Taro
During the past decade, we have observed advance in tuberculosis research including novel vaccines, innate immunity (TLR), SNIP analysis and molecular mechanism of drug resistance. Worldwide genome project enabled the whole genome sequence of host resistant against tuberculosis as well as the whole genome sequence of M. tuberculosis H37Rv. DNA technology has also provided a great impact on the development of novel vaccine against TB. In this symposium, we have invited leading researchers in the field of the frontier study of Mycobacterium research in order to provide general overview of the cutting edge of frontier research. Molecular mechanism of drug resistance of M. tuberculosis has been clarified. On the other hand, molecular mechanism of host-defence (insusceptibility of host) against M. tuberculosis has not yet elucidated. Dr. Taro Shirakawa (Kyoto University) reviewed the susceptibility genes of host in TB infection and presented candidate genes associated with multi-drug resistant tuberculosis. Dr. Naoto Keicho (International Medical Center of Japan) tried to identify host genetic factors involved in susceptibility to pulmonary Mycobacterium avium complex (MAC) infection by candidate gene approach and genome-wide approach. In Japan, Dr. Masaji Okada (National Hospital Organization Kinki-Chuo Chest Medical Center) has been engaged actively in the development of new tuberculosis vaccines (HVJ-liposome/Hsp65 DNA + IL-12 DNA vaccine and recombinant 72f BCG vaccine). He showed basic strategy for construction of new candidate vaccines and also showed significant efficacy on the protection of tuberculosis infection using cynomolgus monkeys, which are very similar to human tuberculosis. Dr. Hatsumi Taniguchi (University of Occupational and Environmental Health) presented that M. tuberculosis mIHF and the neighbor genes went into a dormacy-like state of M. smegmatis in J774 macrophage cells. This study might provide a weapon for elucidating the mechanism of dormacy
Dippenaar, Anzaan; Parsons, Sven David Charles; Sampson, Samantha Leigh; van der Merwe, Ruben Gerhard; Drewe, Julian Ashley; Abdallah, Abdallah Musa; Siame, Kabengele Keith; Gey van Pittius, Nicolaas Claudius; van Helden, Paul David; Pain, Arnab; Warren, Robin Mark
Tuberculosis occurs in various mammalian hosts and is caused by a range of different lineages of the Mycobacterium tuberculosis complex (MTBC). A recently described member, Mycobacterium suricattae, causes tuberculosis in meerkats (Suricata suricatta) in Southern Africa and preliminary genetic analysis showed this organism to be closely related to an MTBC pathogen of rock hyraxes (Procavia capensis), the dassie bacillus. Here we make use of whole genome sequencing to describe the evolution of the genome of M. suricattae, including known and novel regions of difference, SNPs and IS6110 insertion sites. We used genome-wide phylogenetic analysis to show that M. suricattae clusters with the chimpanzee bacillus, previously isolated from a chimpanzee (Pan troglodytes) in West Africa. We propose an evolutionary scenario for the Mycobacterium africanum lineage 6 complex, showing the evolutionary relationship of M. africanum and chimpanzee bacillus, and the closely related members M. suricattae, dassie bacillus and Mycobacterium mungi.
This bacterial infection is caused by Mycobacterium marinum . Marinum is a relative of the organism which causes tuberculosis. This lesion is often referred to as a swimming pool granuloma. Atypical mycobacterial ...
Han, Xiang Y.; Sizer, Kurt Clement; Velarde-Félix, Jesús S.; Frias-Castro, Luis O.; Vargas-Ocampo, Francisco
Summary Background Mycobacterium leprae was the only known cause of leprosy until 2008, when a new species, named Mycobacterium lepromatosis, was found to cause diffuse lepromatous leprosy (DLL), a unique form of leprosy endemic in Mexico. Methods We sought to differentiate the leprosy agents among 120 Mexican patients with various clinical forms of leprosy and to compare their relative prevalence and disease features. Archived skin biopsy specimens from these patients were tested for both M. leprae and M. lepromatosis using polymerase chain reaction-based species-specific assays. Results Eighty-seven (72.5%) patients were confirmed for etiologic species, including 55 with M. lepromatosis, 18 with M. leprae, and 14 with both organisms. The endemic regions of each agent differed but overlapped. Patients with M. lepromatosis were younger and from more states, and their clinical diagnoses included 13 DLL, 34 lepromatous leprosy (LL), and eight other forms of leprosy. By contrast, the diagnoses of patients with M. leprae included none DLL, 15 LL and three other forms. Thus, M. lepromatosis caused DLL specifically (p=0.023). Patients with M. lepromatosis also showed more variable skin lesions and the extremities were the commonest biopsy sites. Finally, patients with dual infections manifested all clinical forms and accounted for 16.1% of all species-confirmed cases. Conclusions M. lepromatosis is another cause of leprosy and is probably more prevalent than M. leprae in Mexico. It mainly causes LL and also specifically DLL. Dual infections caused by both species may occur in endemic area. PMID:22788812
Portaels, F; Chemlal, K; Elsen, P; Johnson, P D; Hayman, J A; Hibble, J; Kirkwood, R; Meyers, W M
Mycobacterium ulcerans infection, or Buruli ulcer, is the third most frequent mycobacterial disease in humans, often causing serious deformities and disability. The disease is most closely associated with tropical wetlands, especially in west and central Africa. Most investigators believe that the aetiological agent proliferates in mud beneath stagnant waters. Modes of transmission may involve direct contact with the contaminated environment, aerosols from water surfaces, and water-dwelling fauna (e.g. insects). Person-to-person transmission is rare. Trauma at the site of skin contamination by M. ulcerans appears to play an important role in initiating disease. Once introduced into the skin or subcutaneous tissue, M. ulcerans multiplies and produces a toxin that causes necrosis. However, the type of disease induced varies from a localised nodule or ulcer, to widespread ulcerative or non-ulcerative disease and osteomyelitis. Although culture of M. ulcerans from a patient was first reported in 1948, attempts to culture the mycobacterium from many specimens of flora and fauna have been unsuccessful. Failure to cultivate this organism from nature may be attributable to inadequate sampling, conditions of transport, decontamination and culture of this fastidious heat-sensitive organism, and to a long generation time relative to that of other environmental mycobacteria. Nevertheless, recent molecular studies using specific primers have revealed M. ulcerans in water, mud, fish and insects. Although no natural reservoir has been found, the possibility that M. ulcerans may colonise microfauna such as free-living amoebae has not been investigated. The host range of experimental infection by M. ulcerans includes lizards, amphibians, chick embryos, possums, armadillos, rats, mice and cattle. Natural infections have been observed only in Australia, in koalas, ringtail possums and a captive alpaca. The lesions were clinically identical to those observed in humans. Mycobacterium
Díez-Delgado, Iratxe; Contreras, Marinela; Vicente, Joaquín; Cabezas-Cruz, Alejandro; Manrique, Marina; Tobes, Raquel; López, Vladimir; Romero, Beatriz; Domínguez, Lucas; Garrido, Joseba M.; Gortazar, Christian
Here we report the complete genome sequences of field isolates of Mycobacterium bovis and the related mycobacterial species, Mycobacterium caprae. The genomes of three M. bovis (MB1, MB3, MB4) and one M. caprae (MB2) field isolates with different virulence, prevalence, and host distribution phenotypes were sequenced. PMID:26112781
de la Fuente, José; Díez-Delgado, Iratxe; Contreras, Marinela; Vicente, Joaquín; Cabezas-Cruz, Alejandro; Manrique, Marina; Tobes, Raquel; López, Vladimir; Romero, Beatriz; Domínguez, Lucas; Garrido, Joseba M; Juste, Ramón; Gortazar, Christian
Here we report the complete genome sequences of field isolates of Mycobacterium bovis and the related mycobacterial species, Mycobacterium caprae. The genomes of three M. bovis (MB1, MB3, MB4) and one M. caprae (MB2) field isolates with different virulence, prevalence, and host distribution phenotypes were sequenced. Copyright © 2015 de la Fuente et al.
Watanabe, Motoko; Ohta, Akihiro; Sasaki, Shun-ichi; Minnikin, David E.
From the lipid fraction of a freeze-dried cell mass of a strain of the Mycobacterium avium-Mycobacterium intracellulare complex, a new glycolipid was isolated and was characterized as 5-mycoloyl-α-arabinofuranosyl (1→1′)-glycerol, mainly on the basis of nuclear magnetic resonance spectroscopy studies. PMID:10094713
Peccia, Jordan; Hernandez, Mark
Photoreactivation was observed in airborne Mycobacterium parafortuitum exposed concurrently to UV radiation (254 nm) and visible light. Photoreactivation rates of airborne cells increased with increasing relative humidity (RH) and decreased with increasing UV dose. Under a constant UV dose with visible light absent, the UV inactivation rate of airborne M. parafortuitum cells decreased by a factor of 4 as RH increased from 40 to 95%; however, under identical conditions with visible light present, the UV inactivation rate of airborne cells decreased only by a factor of 2. When irradiated in the absence of visible light, cellular cyclobutane thymine dimer content of UV-irradiated airborne M. parafortuitum and Serratia marcescens increased in response to RH increases. Results suggest that, unlike in waterborne bacteria, cyclobutane thymine dimers are not the most significant form of UV-induced DNA damage incurred by airborne bacteria and that the distribution of DNA photoproducts incorporated into UV-irradiated airborne cells is a function of RH. PMID:11526027
Shi, Xiaoshan; Darwin, K. Heran
Copper (Cu) is a trace element essential for the growth and development of almost all organisms, including bacteria. However, Cu overload in most systems is toxic. Studies show Cu accumulates in macrophage phagosomes infected with bacteria, suggesting Cu provides an innate immune mechanism to combat invading pathogens. To counteract the host-supplied Cu, increasing evidence suggests that bacteria have evolved Cu resistance mechanisms to facilitate their pathogenesis. In particular, Mycobacterium tuberculosis (Mtb), the causative agent of tuberculosis, has evolved multiple pathways to respond to Cu. Here, we summarize what is currently known about Cu homeostasis in Mtb and discuss potential sources of Cu encountered by this and other pathogens in a mammalian host. PMID:25614981
Zhang, Dao-Feng; Chen, Xiu; Zhang, Xiao-Mei; Zhi, Xiao-Yang; Yao, Ji-Cheng; Jiang, Yi; Xiong, Zhi; Li, Wen-jun
Two novel isolates of rapidly growing, Gram-stain-positive, non-chromogenic species of the genus Mycobacterium, strain YIM M13028(T) from a sediment sample collected from the South China Sea (19° 30.261' N 111° 0.247' E) at a depth of 42 m and strain YIM 121001(T) from a coastal zone sand sample collected in Dubai, United Arab Emirates, were obtained in our laboratory. Their taxonomic positions were determined by a polyphasic approach. Good growth of the two strains was observed at 28 °C and pH 7.0 with 0-2 % NaCl on tryptic soy agar medium. Both strains formed round orange-red colonies, strain YIM M13028(T) had a rough surface, while YIM 121001(T) was smooth. Cellular fatty acids, whole-cell protein profiles and TLC analysis of their mycolic acids show significant differences from reference stains. Phenotypic characteristics and multilocus sequence analysis (MLSA) of 16S rRNA gene, hsp65, rpoB and 16S-23S internal transcribed spacer (ITS) sequences indicated that both strains YIM M13028(T) and YIM 121001(T) belong to the genus Mycobacterium. DNA-DNA hybridization values revealed a low relatedness (<70 %) of the two isolates with the type strains Mycobacterium neoaurum DSM 44074(T) and Mycobacterium hodleri DSM 44183(T). The low DNA-DNA hybridization values (40.4±3.5 %) between strains YIM M13028(T) and YIM 121001(T) and phenotypic distinctiveness indicated that the two strains were representatives of different novel species of the genus Mycobacterium. The names proposed for these novel species are Mycobacterium sediminis sp. nov. and Mycobacterium arabiense sp. nov., and the type strains are YIM M13028(T) ( = DSM 45643(T) = KCTC 19999(T)) and YIM 121001(T) ( = DSM 45768(T) = JCM 18538(T)), respectively.
Phelan, Jody; Maitra, Arundhati; McNerney, Ruth; Nair, Mridul; Gupta, Antima; Coll, Francesc; Pain, Arnab; Bhakta, Sanjib; Clark, Taane G
Mycobacterium aurum (M. aurum) is an environmental mycobacteria that has previously been used in studies of anti-mycobacterial drugs due to its fast growth rate and low pathogenicity. The M. aurum genome has been sequenced and assembled into 46 contigs, with a total length of 6.02Mb containing 5684 annotated protein-coding genes. A phylogenetic analysis using whole genome alignments positioned M. aurum close to Mycobacterium vaccae and Mycobacterium vanbaalenii, within a clade related to fast-growing mycobacteria. Large-scale genomic rearrangements were identified by comparing the M. aurum genome to those of Mycobacterium tuberculosis and Mycobacterium leprae. M. aurum orthologous genes implicated in resistance to anti-tuberculosis drugs in M. tuberculosis were observed. The sequence identity at the DNA level varied from 68.6% for pncA (pyrazinamide drug-related) to 96.2% for rrs (streptomycin, capreomycin). We observed two homologous genes encoding the catalase-peroxidase enzyme (katG) that is associated with resistance to isoniazid. Similarly, two embB homologues were identified in the M. aurum genome. In addition to describing for the first time the genome of M. aurum, this work provides a resource to aid the use of M. aurum in studies to develop improved drugs for the pathogenic mycobacteria M. tuberculosis and M. leprae.
Phelippeau, M.; Asmar, S.; Osman, D. Aboubaker; Sassi, M.; Robert, C.; Michelle, C.; Musso, D.; Drancourt, M.
In French Polynesia, respiratory tract clinical isolate M26, displayed unusual phenotype and contradictory phylogenetic affiliations, suggesting a hitherto unidentified rapidly-growing Mycobacterium species. The phenotype of strain M26 was further characterized and its genome sequenced. Strain M26 genome consists in a 5,732,017-bp circular chromosome with a G + C% of 67.54%, comprising 5,500 protein-coding genes and 52 RNA genes (including two copies of the 16 S rRNA gene). One region coding for a putative prophage was also predicted. An intriguing characteristic of strain M26’s genome is the large number of genes encoding polyketide synthases and nonribosomal peptide synthases. Phylogenomic analysis showed that strain M26’s genome is closest to the Mycobacterium phlei genome with a 76.6% average nucleotide identity. Comparative genomics of 33 Mycobacterium genomes yielded 361 genes unique to M26 strain which functional annotation revealed 84.21% of unknown function and 3.88% encoding lipid transport and metabolism; while 48.87% of genes absent in M26 strain have unknown function, 9.5% are implicated in transcription and 19% are implicated in transport and metabolism. Strain M26’s unique phenotypic and genomic characteristics indicate it is representative of a new species named “Mycobacterium massilipolynesiensis”. Looking for mycobacteria in remote areas allows for the discovery of new Mycobacterium species. PMID:28074866
Macente, Sara; Helbel, Cesar; Souza, Simone Felizardo Rocha; Siqueira, Vera Lúcia Dias; Padua, Rubia Andreia Falleiros; Cardoso, Rosilene Fressatti
Mycobacterium fortuitum is a non-tuberculous fast-growing mycobacterium which is frequently acquired from environmental sources such as soil and water. Since it is an opportunist pathogen, it is associated with trauma, surgery or immunodeficiency. The current report describes a case of Mycobacterium fortuitum-caused disseminated lesions on the skin of an immunocompetent patient. PMID:23539012
Macente, Sara; Helbel, Cesar; Souza, Simone Felizardo Rocha; Siqueira, Vera Lúcia Dias; Padua, Rubia Andreia Falleiros; Cardoso, Rosilene Fressatti
Mycobacterium fortuitum is a non-tuberculous fast-growing mycobacterium which is frequently acquired from environmental sources such as soil and water. Since it is an opportunist pathogen, it is associated with trauma, surgery or immunodeficiency. The current report describes a case of Mycobacterium fortuitum-caused disseminated lesions on the skin of an immunocompetent patient.
van Ingen, J; Boeree, M J; Kösters, K; Wieland, A; Tortoli, E; Dekhuijzen, P N R; van Soolingen, D
The Mycobacterium avium complex (MAC) consists of four recognized species, Mycobacterium avium, Mycobacterium colombiense, Mycobacterium intracellulare and Mycobacterium chimaera, and a variety of other strains that may be members of undescribed taxa. We report on two isolates of a scotochromogenic, slowly growing, non-tuberculous Mycobacterium species within the M. avium complex from a lymph node and an infected wound after a dogbite of separate patients in The Netherlands. The extrapulmonary infections in immunocompetent patients suggested a high level of virulence. These isolates were characterized by a unique nucleotide sequence in the 16S rRNA gene, 99% similar to Mycobacterium colombiense, and the MAC-Q 16S-23S internal transcribed spacer (ITS) sequence. Sequence analyses of the hsp65 gene revealed 97% similarity to M. avium. The rpoB gene sequence was 98% similar to M. colombiense. Phenotypically, the scotochromogenicity, positive semi-quantitative catalase and heat-stable catalase tests, negative tellurite reductase and urease tests and susceptibility to hydroxylamine and oleic acid set these isolates apart from related species. High-performance liquid chromatography analysis of cell-wall mycolic acid content revealed a unique pattern, related to that of M. avium and M. colombiense. Together, these findings supported a separate species status within the Mycobacterium avium complex. We propose elevation of scotochromogenic M. avium complex strains sharing this 16S gene and MAC-Q ITS sequence to separate species status, for which the name Mycobacterium vulneris sp. nov. is proposed. The type strain is NLA000700772T (=DSM 45247T=CIP 109859T).
Stewardson, Andrew J; Stuart, Rhonda L; Cheng, Allen C; Johnson, Paul Dr
There is an ongoing investigation into infections with non-tuberculous mycobacteria associated with contaminated heater-cooler units used in cardiac surgery. The overall risk is low, but surgical site and disseminated infections have been reported, including one possible case in Australia, mainly with surgery involving implantation of prosthetic material. Mycobacterium chimaera infection should be considered in patients who have previously undergone surgery with cardiopulmonary bypass and who present with cardiac or disseminated infection or sternal wound infection unresponsive to standard antibiotic therapy. Where cases are suspected, patients should be investigated and managed in consultation with an infectious diseases physician and/or clinical microbiologist. If cases are confirmed or heater-cooler devices are found to be contaminated, details should be reported to the hospital infection control team, the jurisdictional health department, the Therapeutic Goods Administration and the Australian distributor of the affected heater-cooler unit(s). Measures to manage risk should include communicating with relevant hospital departments, ensuring that the manufacturer's updated instructions for use are followed, regular testing of machines, and reviewing the location of machines when in use.
Master, Sharon S; Rampini, Silvana K; Davis, Alexander S; Keller, Christine; Ehlers, Stefan; Springer, Burkhard; Timmins, Graham S; Sander, Peter; Deretic, Vojo
Mycobacterium tuberculosis (Mtb) parasitizes host macrophages and subverts host innate and adaptive immunity. Several cytokines elicited by Mtb are mediators of mycobacterial clearance or are involved in tuberculosis pathology. Surprisingly, interleukin-1beta (IL-1beta), a major proinflammatory cytokine, has not been implicated in host-Mtb interactions. IL-1beta is activated by processing upon assembly of the inflammasome, a specialized inflammatory caspase-activating protein complex. Here, we show that Mtb prevents inflammasome activation and IL-1beta processing. An Mtb gene, zmp1, which encodes a putative Zn(2+) metalloprotease, is required for this process. Infection of macrophages with zmp1-deleted Mtb triggered activation of the inflammasome, resulting in increased IL-1beta secretion, enhanced maturation of Mtb containing phagosomes, improved mycobacterial clearance by macrophages, and lower bacterial burden in the lungs of aerosol-infected mice. Thus, we uncovered a previously masked role for IL-1beta in the control of Mtb and a mycobacterial system that prevents inflammasome and, therefore, IL-1beta activation.
Gengenbacher, Martin; Kaufmann, Stefan H. E.
Tuberculosis (TB) remains a major health threat, killing near to 2 million individuals around this globe, annually. The sole vaccine developed almost a century ago, provides limited protection only during childhood. After decades without the introduction of new antibiotics, several candidates are currently undergoing clinical investigation. Curing TB requires prolonged combination chemotherapy with several drugs. Moreover, monitoring the success of therapy is questionable due to the lack of reliable biomarkers. To substantially improve the situation, a detailed understanding of the crosstalk between human host and the pathogen Mycobacterium tuberculosis (Mtb) is vital. Principally, Mtb’s enormous success is based on three capacities: First, reprogramming of macrophages after primary infection/phagocytosis in order to prevent its own destruction; second, initiating the formation of well-organized granulomas, comprising different immune cells to create a confined environment for the host–pathogen standoff; third, the capability to shut down its own central metabolism, terminate replication and thereby transit into a stage of dormancy rendering itself extremely resistant to host defense and drug treatment. Here we review the molecular mechanisms underlying these processes, draw conclusions in a working model of mycobacterial dormancy and highlight gaps in our understanding to be addressed in future research. PMID:22320122
Bruijnesteijn van Coppenraet, Lesla E.S.; Lindeboom, Jerome A.; Prins, Jan M.; Claas, Eric C. J.
Infections associated with Mycobacterium haemophilum are underdiagnosed because specific culture methods required for its recovery are not applied routinely. Using polymerase chain reaction (PCR) technology on fine needle aspirates and biopsied specimens from 89 children with cervicofacial lymphadenitis, we assessed the importance of M. haemophilum. Application of a Mycobacterium genus–specific real-time PCR in combination with amplicon sequencing and a M. haemophilum–specific PCR resulted in the recognition of M. haemophilum as the causative agent in 16 (18%) children with cervicofacial lymphadenitis. Mycobacterium avium was the most frequently found species (56%), and M. haemophilum was the second most commonly recognized pathogen. Real-time PCR results were superior to culture because only 9 (56%) of the 16 diagnosed M. haemophilum infections were positive by culture. PMID:15705324
We report the draft genome sequence of the type strain Mycobacterium chimaera Fl-0169T, a member of the Mycobacterium avium complex (MAC). M. chimaera Fl-0169T was isolated from a patient in Italy and is highly similar to strains of M. chimaera isolated in Ireland, though Fl-0169T possesses unique virulence genes. Evidence suggests that M. avium, M. intracellulare, and M. chimaera are differently virulent and a comparative genomic analysis is critically needed to identify diagnostic targets that reliably differentiate species of MAC. With treatment costs for Mycobacterium infections estimated to be >$1.8 B annually in the U.S., correct species identification will result in improved treatment selection, lower costs, and improved patient outcomes.
Suvanasuthi, Saroj; Wongpraparut, Chanisada; Pattanaprichakul, Penvadee; Bunyaratavej, Sumanas
A case of cutaneous Mycobacterium fortuitum infection after receiving an amateur tattoo is reported. A few days after tattooing, an otherwise healthy 25-year-old Thai male presented with multiple discrete erythematous papules confined to the tattoo area. He was initially treated with topical steroid and oral antihistamine without improvement. Skin biopsy was carried out, and the histopathology showed mixed cell granuloma with a foreign body reaction (tattoo color pigments). The acid-fast bacilli stain was positive. The tissue culture grew M. fortuitum two weeks later. He was treated with clarithromycin 1,000 mg/day and ciprofloxacin 1,000 mg/day for 10 months with complete response. From the clinical aspect, tattoo-associated rapidly growing mycobacterium infection might be difficult to differentiate from the pigment-based skin reactions. Skin biopsy for histopathology and tissue culture for Mycobacterium probably will be needed in arriving at the diagnosis.
Mycobacterium tuberculosis is an old enemy of the human race, with evidence of infection observed as early as 5000 years ago. Although more host-restricted than Mycobacterium bovis, which can infect all warm-blooded vertebrates, M. tuberculosis can infect, and cause morbidity and mortality in, several veterinary species as well. As M. tuberculosis is one of the earliest described bacterial pathogens, the literature describing this organism is vast and overwhelming. This review strives to distill what is currently known about this bacterium and the disease it causes for the veterinary pathologist.
Roberts, M C; McMillan, C; Coyle, M B
Whole chromosomal DNA probes were used to identify clinical isolates of Mycobacterium tuberculosis, Mycobacterium avium complex, and Mycobacterium gordonae. The probe for M. tuberculosis was prepared from Mycobacterium bovis BCG, which has been shown to be closely related to M. tuberculosis. A probe for the M. avium complex was prepared from three strains representing each of the three DNA homology groups in the M. avium complex. The probes were used in dot blot assays to identify clinical isolates of mycobacteria. The dot blot test correctly identified 57 of the 61 (93%) cultures grown on solid media, and 100% of antibiotic-treated broth-grown cells were correctly identified. Identification by dot blot required a maximum of 48 h. When the probes were tested against 63 positive BACTEC (Johnston Laboratories, Inc., Towson, Md.) cultures of clinical specimens, 59% were correctly identified. However, of the 14 BACTEC cultures that had been treated with antibiotics before being lysed, 13 (93%) were correctly identified. PMID:3112180
Hernández García, A M; Arias, A; Felipe, A; Alvarez, R; Sierra, A
The in vitro susceptibility of 32 Mycobacterium chelonae strains to 10 antimicrobial agents was determined. The sources of the different strains were: clinical samples from patients treated at the Hospital Universitario de Canarias and Hospital del Tórax (General and Chest facilities) and from environmental sources (water supply, sewage, swimming pools and the sea). The susceptibility tests were performed by a broth microdilution method (Mueller-Hinton Broth). The results showed amikacin as the most effective antimicrobial agent against M. chelonae isolates, then ofloxacin and cefoxitin. However no statistical difference was detected among them. The least effective was imipenem, followed by ciprofloxacin and norfloxacin.
Bruce-Micah, R.; Gamm, U.; Hüttenberger, D.; Cullum, J.; Foth, H.-J.
Photodynamic inactivation (PDI) of bacterial strains presents an attractive potential alternative to antibiotic therapies. Success is dependent on the effective accumulation in bacterial cells of photochemical substances called photosensitizers, which are usually porphyrins or their derivatives. The kinetics of porphyrin synthesis after treatment with the precursor ALA and the accumulation of the Chlorin e6 and the following illumination were studied. The goal was to estimate effectivity of the destructive power of these PS in vitro in respect of the physiological states of Mycobacteria. So the present results examine the cell destruction by PDI using ALA-induced Porphyrins and Chlorin e6 accumulated in Mycobacterium phlei and Mycobacterium smegmatis, which serve as models for the important pathogens Mycobacterium tuberculosis, Mycobacterium leprae and Mycobacterium bovis. We could show that both Mycobacterium after ALA and Chlorin e6 application were killed by illumination with light of about 662 nm. A reduction of about 97% could be reached by using a lightdose of 70 mW/cm2.
Willumsen, P; Karlson, U; Stackebrandt, E; Kroppenstedt, R M
A polycyclic aromatic hydrocarbon-degrading bacterium isolated from coal tar-contaminated soil in Denmark was characterized by a polyphasic approach. Phylogenetically and chemotaxonomically, it was related to members of the genus Mycobacterium. The isolate contains chemotaxonomic markers that are diagnostic for the genus Mycobacterium; i.e. the meso isomer of 2,6-diaminopimelic acid, arabinose and galactose as diagnostic whole-cell sugars, MK-9(H2) as the principal isoprenoid quinone, a mycolic acid pattern of alpha-mycolates, ketomycolates and wax-ester mycolates, unbranched saturated and unsaturated fatty acids plus a small amount of tuberculostearic acid and a significant amount of a C18:0 secondary alcohol. Based on the unique combination of chemical markers among mycobacteria, it is proposed that the isolate should be assigned to a new species, Mycobacterium frederiksbergense sp. nov. This novel species is phylogenetically closely related to Mycobacterium diernhoferi, Mycobacterium neoaurum and Mycobacterium hodleri. The type strain of M. frederiksbergense is strain FAn9T (= DSM 44346T = NRRL B-24126T).
Gold, Ben; Nathan, Carl
While the immune system is credited with averting tuberculosis in billions of individuals exposed to Mycobacterium tuberculosis, the immune system is also culpable for tempering the ability of antibiotics to deliver swift and durable cure of disease. In individuals afflicted with tuberculosis, host immunity produces diverse microenvironmental niches that support suboptimal growth, or complete growth arrest, of M. tuberculosis. The physiological state of nonreplication in bacteria is associated with phenotypic drug tolerance. Many of these host microenvironments, when modeled in vitro by carbon starvation, complete nutrient starvation, stationary phase, acidic pH, reactive nitrogen intermediates, hypoxia, biofilms, and withholding streptomycin from the streptomycin-addicted strain SS18b, render M. tuberculosis profoundly tolerant to many of the antibiotics that are given to tuberculosis patients in a clinical setting. Targeting nonreplicating persisters is anticipated to reduce the duration of antibiotic treatment and rate of post-treatment relapse. Some promising drugs to treat tuberculosis, such as rifampicin and bedaquiline, only kill nonreplicating M. tuberculosis in vitro at concentrations far greater than their minimal inhibitory concentrations against replicating bacilli. There is an urgent demand to identify which of the currently used antibiotics, and which of the molecules in academic and corporate screening collections, have potent bactericidal action on nonreplicating M. tuberculosis. With this goal, we review methods of high throughput screening to target nonreplicating M. tuberculosis and methods to progress candidate molecules. A classification based on structures and putative targets of molecules that have been reported to kill nonreplicating M. tuberculosis revealed a rich diversity in pharmacophores. However, few of these compounds were tested under conditions that would exclude the impact of adsorbed compound acting during the recovery phase of
Thomas, Suzanne T.; VanderVen, Brian C.; Sherman, David R.; Russell, David G.; Sampson, Nicole S.
Mycobacterium tuberculosis, the bacterium that causes tuberculosis, imports and metabolizes host cholesterol during infection. This ability is important in the chronic phase of infection. Here we investigate the role of the intracellular growth operon (igr), which has previously been identified as having a cholesterol-sensitive phenotype in vitro and which is important for intracellular growth of the mycobacteria. We have employed isotopically labeled low density lipoproteins containing either [1,7,15,22,26-14C]cholesterol or [1,7,15,22,26-13C]cholesterol and high resolution LC/MS as tools to profile the cholesterol-derived metabolome of an igr operon-disrupted mutant (Δigr) of M. tuberculosis. A partially metabolized cholesterol species accumulated in the Δigr knock-out strain that was absent in the complemented and parental wild-type strains. Structural elucidation by multidimensional 1H and 13C NMR spectroscopy revealed the accumulated metabolite to be methyl 1β-(2′-propanoate)-3aα-H-4α-(3′-propanoic acid)-7aβ-methylhexahydro-5-indanone. Heterologously expressed and purified FadE28-FadE29, an acyl-CoA dehydrogenase encoded by the igr operon, catalyzes the dehydrogenation of 2′-propanoyl-CoA ester side chains in substrates with structures analogous to the characterized metabolite. Based on the structure of the isolated metabolite, enzyme activity, and bioinformatic annotations, we assign the primary function of the igr operon to be degradation of the 2′-propanoate side chain. Therefore, the igr operon is necessary to completely metabolize the side chain of cholesterol metabolites. PMID:22045806
DITSE, ZANELE; LAMERS, MEINDERT H.; WARNER, DIGBY F.
Faithful replication and maintenance of the genome are essential to the ability of any organism to survive and propagate. For an obligate pathogen such as Mycobacterium tuberculosis that has to complete successive cycles of transmission, infection, and disease in order to retain a foothold in the human population, this requires that genome replication and maintenance must be accomplished under the metabolic, immune, and antibiotic stresses encountered during passage through variable host environments. Comparative genomic analyses have established that chromosomal mutations enable M. tuberculosis to adapt to these stresses: the emergence of drug-resistant isolates provides direct evidence of this capacity, so too the well-documented genetic diversity among M. tuberculosis lineages across geographic loci, as well as the microvariation within individual patients that is increasingly observed as whole-genome sequencing methodologies are applied to clinical samples and tuberculosis (TB) disease models. However, the precise mutagenic mechanisms responsible for M. tuberculosis evolution and adaptation are poorly understood. Here, we summarize current knowledge of the machinery responsible for DNA replication in M. tuberculosis, and discuss the potential contribution of the expanded complement of mycobacterial DNA polymerases to mutagenesis. We also consider briefly the possible role of DNA replication—in particular, its regulation and coordination with cell division—in the ability of M. tuberculosis to withstand antibacterial stresses, including host immune effectors and antibiotics, through the generation at the population level of a tolerant state, or through the formation of a subpopulation of persister bacilli—both of which might be relevant to the emergence and fixation of genetic drug resistance. PMID:28361736
Background Mycobacterium abscessus group includes antibiotic-resistant, opportunistic mycobacteria that are responsible for sporadic cases and outbreaks of cutaneous, pulmonary and disseminated infections. However, because of their close genetic relationships, accurate discrimination between the various strains of these mycobacteria remains difficult. In this report, we describe the development of a multispacer sequence typing (MST) analysis for the simultaneous identification and typing of M. abscessus mycobacteria. We also compared MST with the reference multilocus sequence analysis (MLSA) typing method. Results Based on the M. abscessus CIP104536T genome, eight intergenic spacers were selected, PCR amplified and sequenced in 21 M. abscessus isolates and analysed in 48 available M. abscessus genomes. MST and MLSA grouped 37 M. abscessus organisms into 12 and nine types, respectively; four formerly “M. bolletii” organisms and M. abscessus M139 into three and four types, respectively; and 27 formerly “M. massiliense” organisms grouped into nine and five types, respectively. The Hunter-Gaston index was off 0.912 for MST and of 0.903 for MLSA. The MST-derived tree was similar to that based on MLSA and rpoB gene sequencing and yielded three main clusters comprising each the type strain of the respective M. abscessus sub-species. Two isolates exhibited discordant MLSA- and rpoB gene sequence-derived position, one isolate exhibited discordant MST- and rpoB gene sequence-derived position and one isolate exhibited discordant MST- and MLSA-derived position. MST spacer n°2 sequencing alone allowed for the accurate identification of the different isolates at the sub-species level. Conclusions MST is a new sequencing-based approach for both identifying and genotyping M. abscessus mycobacteria that clearly differentiates formerly “M. massiliense” organisms from other M. abscessus subsp. bolletii organisms. PMID:23294800
The electrophoretic mobilities (EPMs) of thirty Mycobacterium avium Complex (MAC) organisms were measured. The EPMs of fifteen clinical isolates ranged from -1.9 to -5.0 µm cm V-1s-1, and the EPMs of fifteen environmental isolates ranged from -1...
Granulomatous lobular mastitis is a rare inflammatory disease of the breast of unknown etiology. Most present as breast masses in women of child-bearing age. A 29-year-old female presented with a swollen, firm and tender right breast, initially misdiagnosed as mastitis. Core needle biopsy revealed findings consistent with granulomatous lobular mastitis, and cultures were all negative for an infectious etiology. She was started on steroid therapy to which she initially responded well. A few weeks later she deteriorated and was found to have multiple breast abscesses. She underwent operative drainage and cultures grew Mycobacterium fortuitum. Granulomatous lobular mastitis is a rare inflammatory disease of the breast. The definitive diagnose entails a biopsy. Other causes of chronic or granulomatous mastitis should be ruled out, including atypical or rare bacteria such as Mycobacterium fortuitum. This is the first reported case of granulomatous mastitis secondary to Mycobacterium fortuitum. With pathologic confirmation of granulomatous mastitis, an infectious etiology must be ruled out. Atypical bacteria such as Mycobacterium fortuitum may not readily grow on cultures, as with our case. Medical management is appropriate, with surgical excision reserved for refractory cases or for drainage of abscesses.
Tan, Nicholas; Sampath, Rahul; Abu Saleh, Omar M; Tweet, Marysia S; Jevremovic, Dragan; Alniemi, Saba; Wengenack, Nancy L; Sampathkumar, Priya; Badley, Andrew D
Ten case reports of disseminated Mycobacterium chimaera infections associated with cardiovascular surgery were published from Europe. We report 3 cases of disseminated M chimaera infections with histories of aortic graft and/or valvular surgery within the United States. Two of 3 patients demonstrated ocular involvement, a potentially important clinical finding.
Tan, Nicholas; Sampath, Rahul; Abu Saleh, Omar M.; Tweet, Marysia S.; Jevremovic, Dragan; Alniemi, Saba; Wengenack, Nancy L.; Sampathkumar, Priya; Badley, Andrew D.
Ten case reports of disseminated Mycobacterium chimaera infections associated with cardiovascular surgery were published from Europe. We report 3 cases of disseminated M chimaera infections with histories of aortic graft and/or valvular surgery within the United States. Two of 3 patients demonstrated ocular involvement, a potentially important clinical finding. PMID:27703994
The electrophoretic mobilities (EPMs) of thirty Mycobacterium avium Complex (MAC) organisms isolated from clinical and environmental sources were measured in 9.15 mM KH2PO4 buffered water. The EPMs of fifteen clinical isolates ranged from -1.9 to -5.0 µm cm V-1 ...
Alexander, Kathleen A; Laver, Pete N; Michel, Anita L; Williams, Mark; van Helden, Paul D; Warren, Robin M; Gey van Pittius, Nicolaas C
Seven outbreaks involving increasing numbers of banded mongoose troops and high death rates have been documented. We identified a Mycobacterium tuberculosis complex pathogen, M. mungi sp. nov., as the causative agent among banded mongooses that live near humans in Chobe District, Botswana. Host spectrum and transmission dynamics remain unknown.
Background Mycobacterium abscessus is an emerging opportunistic pathogen which diversity was acknowledged by the recent description of two subspecies accommodating M. abscessus, Mycobacterium bolletii and Mycobacterium massiliense isolates. Results Here, genome analysis found 1–8 prophage regions in 47/48 M. abscessus genomes ranging from small prophage-like elements to complete prophages. A total of 20,304 viral and phage proteins clustered into 853 orthologous groups. Phylogenomic and phylogenetic analyses based on prophage region homology found three main clusters corresponding to M. abscessus, M. bolletii and M. massiliense. Analysing 135 annotated Tape Measure Proteins found thirteen clusters and four singletons, suggesting that at least 17 mycobacteriophages had infected M. abscessus during its evolution. The evolutionary history of phages differed from that of their mycobacterial hosts. In particular, 33 phage-related proteins have been horizontally transferred within M. abscessus genomes. They comprise of an integrase, specific mycobacteriophage proteins, hypothetical proteins and DNA replication and metabolism proteins. Gene exchanges, loss and gains which occurred in M. abscessus genomes have been driven by several mycobacteriophages. Conclusions This analysis of phage-mycobacterium co-evolution suggests that mycobacteriophages are playing a key-role in the on-going diversification of M. abscessus. Reviewers This article was reviewed by Eric Bapteste, Patrick Forterre and Eugene Koonin. PMID:25224692
The electrophoretic mobilities (EPMs) of thirty Mycobacterium avium Complex (MAC) organisms were measured. The EPMs of fifteen clinical isolates ranged from -1.9 to -5.0 µm cm V-1s-1, and the EPMs of fifteen environmental isolates ranged from -1...
Das, Sarbashis; Pettersson, B. M. Fredrik; Behra, Phani Rama Krishna; Ramesh, Malavika; Dasgupta, Santanu; Bhattacharya, Alok; Kirsebom, Leif A.
Mycobacterium phlei, a nontuberculosis mycobacterial species, was first described in 1898–1899. We present the complete genome sequence for the M. phlei CCUG21000T type strain and the draft genomes for four additional strains. The genome size for all fiveis 5.3 Mb with 69.4% Guanine-Cytosine content. This is ≈0.35 Mbp smaller than the previously reported M. phlei RIVM draft genome. The size difference is attributed partly to large bacteriophage sequence fragments in the M. phlei RIVM genome. Comparative analysis revealed the following: 1) A CRISPR system similar to Type 1E (cas3) in M. phlei RIVM; 2) genes involved in polyamine metabolism and transport (potAD, potF) that are absent in other mycobacteria, and 3) strain-specific variations in the number of σ-factor genes. Moreover, M. phlei has as many as 82 mce (mammalian cell entry) homologs and many of the horizontally acquired genes in M. phlei are present in other environmental bacteria including mycobacteria that share similar habitat. Phylogenetic analysis based on 693 Mycobacterium core genes present in all complete mycobacterial genomes suggested that its closest neighbor is Mycobacterium smegmatis JS623 and Mycobacterium rhodesiae NBB3, while it is more distant to M. smegmatis mc2 155. PMID:26941228
The electrophoretic mobilities (EPMs) of thirty Mycobacterium avium Complex (MAC) organisms isolated from clinical and environmental sources were measured in 9.15 mM KH2PO4 buffered water. The EPMs of fifteen clinical isolates ranged from -1.9 to -5.0 µm cm V-1 ...
Kaufmann, Stefan H.E.; Cole, Stewart T.; Mizrahi, Valerie; Rubin, Eric; Nathan, Carl
Mycobacterium tuberculosis remains a leading cause of morbidity and mortality worldwide. Advances reported at a recent international meeting highlight insights and controversies in the genetics of M. tuberculosis and the infected host, the nature of protective immune responses, adaptation of the bacillus to host-imposed stresses, animal models, and new techniques. PMID:15939785
LeBlanc, Jaclyn; Webster, Duncan; Tyrrell, Gregory J; Chiu, Isabelle
A case of cutaneous Mycobacterium marinum infection acquired from Artemia nyos (sea monkeys) is presented. The infection was unresponsive to initial antimicrobial therapies. A biopsy of a lesion revealed granulomatous inflammation with cultures that subsequently grew M marinum. A three-month course of clarithromycin provided complete resolution. PMID:24294280
Aylward, G. W.; Stacey, A. R.; Marsh, R. J.
We present a case of Mycobacterium chelonei infection in a corneal graft. The chronic ulceration and stromal infiltration followed a well defined course and eventually responded to topical amikacin, though a further graft was required. Previous cases of keratitis due to the M. fortuitum complex are reviewed. Images PMID:3311141
McCullough, W G; Merkal, R S
A iron-chelating monohydroxamate was isolated from cultures of Mycobacterium avium grown on an iron-limiting medium. The hydroxyamate metabolite was characterized by chemical degradation and spectral measurements as L-alpha-asparaginyl-L-alpha-(N-hydroxy)-asparagine. PMID:185194
Granulomatous lobular mastitis is a rare inflammatory disease of the breast of unknown etiology. Most present as breast masses in women of child-bearing age. A 29-year-old female presented with a swollen, firm and tender right breast, initially misdiagnosed as mastitis. Core needle biopsy revealed findings consistent with granulomatous lobular mastitis, and cultures were all negative for an infectious etiology. She was started on steroid therapy to which she initially responded well. A few weeks later she deteriorated and was found to have multiple breast abscesses. She underwent operative drainage and cultures grew Mycobacterium fortuitum. Granulomatous lobular mastitis is a rare inflammatory disease of the breast. The definitive diagnose entails a biopsy. Other causes of chronic or granulomatous mastitis should be ruled out, including atypical or rare bacteria such as Mycobacterium fortuitum. This is the first reported case of granulomatous mastitis secondary to Mycobacterium fortuitum. With pathologic confirmation of granulomatous mastitis, an infectious etiology must be ruled out. Atypical bacteria such as Mycobacterium fortuitum may not readily grow on cultures, as with our case. Medical management is appropriate, with surgical excision reserved for refractory cases or for drainage of abscesses. PMID:28035314
Aerosol and intratracheal inoculation routes are commonly used for experimental biology purposes to infect cattle with virulent Mycobacterium bovis, each resulting primarily in a respiratory tract infection including lungs and lung-associated lymph nodes. Disease severity is dose and time dependent...
Davidson, Rebecca M; DeGroote, Mary Ann; Marola, Jamie L; Buss, Sarah; Jones, Victoria; McNeil, Michael R; Freifeld, Alison G; Elaine Epperson, L; Hasan, Nabeeh A; Jackson, Mary; Iwen, Peter C; Salfinger, Max; Strong, Michael
A novel slowly growing, non-chromogenic species of the class Actinobacteria was isolated from a human respiratory sample in Nebraska, USA, in 2012. Analysis of the internal transcribed spacer sequence supported placement into the genus Mycobacterium with high sequence similarity to a previously undescribed strain isolated from a patient respiratory sample from Oregon, USA, held in a collection in Colorado, USA, in 2000. The two isolates were subjected to phenotypic testing and whole genome sequencing and found to be indistinguishable. The bacteria were acid-fast stain-positive, rod-shaped and exhibited growth after 7-10 days on solid media at temperatures ranging from 25 to 42°C. Colonies were non-pigmented, rough and slightly raised. Analyses of matrix-assisted laser desorption ionization time-of-flight profiles showed no matches against a reference library of 130 mycobacterial species. Full-length 16S rRNA gene sequences were identical for the two isolates, the average nucleotide identity (ANI) between their genomes was 99.7 % and phylogenetic comparisons classified the novel mycobacteria as the basal most species in the slowly growing Mycobacterium clade. Mycobacterium avium is the most closely related species based on rpoB gene sequence similarity (92 %), but the ANI between the genomes was 81.5 %, below the suggested cut-off for differentiating two species (95 %). Mycolic acid profiles were more similar to M. avium than to Mycobacterium simiae or Mycobacterium abscessus. The phenotypic and genomic data support the conclusion that the two related isolates represent a novel Mycobacterium species for which the name Mycobacterium talmoniae sp. nov. is proposed. The type strain is NE-TNMC-100812T (=ATCC BAA-2683T=DSM 46873T).
Satti, Luqman; Abbasi, Shahid; Sattar, Abdul; Ikram, Aamer; Manzar, Muhammad Adnan; Khalid, Malik Muhammad
Incidence and prevalence of Mycobacterium fortuitum infection vary greatly by location and death is very rare except in disseminated disease in immunocompromised individuals. We present what we believe is the first case of bone marrow infection with Mycobacterium fortuitum in an HIV negative patient. Bone marrow examination revealed presence of numerous acid fast bacilli which were confirmed as Mycobacterium fortuitum on culture and by molecular analysis. Patient was managed successfully with amikacin and ciprofloxacin.
Mycobacterium Xenopi Found Incidentally on MRI of the Cervical Spine Military Medicine Radiology Corner, Vol. 175. January, 2010 Radiology Corner...Mycobacterium Xenopi Found Incidentally on MRI of the Cervical Spine Guarantor: Chris Walker1 Contributors: Chris Walker; 1 Col Les Folio...Mycobacterium xenopi in her lung. A mass was incidentally noted in the right upper apex on an MRI ordered to evaluate a subluxation seen in her cervical
Lee, So-Young; Kim, Byoung-Jun; Kim, Hong; Won, Yu-Seop; Jeon, Che Ok; Jeong, Joseph; Lee, Seon Ho; Lim, Ji-Hun; Lee, Seung-Heon; Kim, Chang Ki; Kook, Yoon-Hoh; Kim, Bum-Joon
Three mycobacterial strains, isolated from independent Korean patients with pulmonary infections, belonging to the Mycobacterium intracellulare genotype 1 (INT-1) were characterized using a polyphasic approach. The sequences of the 16S rRNA gene and internal transcribed spacer 1 (ITS1) of the INT-1 strains were identical to those of Mycobacterium intracellulare ATCC 13950T. However, multilocus sequence typing (MLST) analysis targeting five housekeeping genes (hsp65, rpoB, argG, gnd and pgm) revealed the phylogenetic separation of these strains from M. intracellulare ATCC 13950T. DNA-DNA hybridization values of >70 % confirmed that the three isolates belong to the same species, while the values of <70 % between one of them and the type strains of M. intracellulare and Mycobacterium chimaera confirmed their belonging to a distinct species. In addition, phenotypic characteristics such as positive growth on MacConkey agar and in acidic broth culture, unique matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) MS profiles of lipids, and unique mycolic acids profiles further supported the taxonomic status of these strains as representatives of a novel species of the Mycobacterium avium complex named Mycobacterium paraintracellulare. The type strain is MOTT64T (=KCTC 29084T=JCM 30622T).
Stinear, Timothy P.; Seemann, Torsten; Harrison, Paul F.; Jenkin, Grant A.; Davies, John K.; Johnson, Paul D.R.; Abdellah, Zahra; Arrowsmith, Claire; Chillingworth, Tracey; Churcher, Carol; Clarke, Kay; Cronin, Ann; Davis, Paul; Goodhead, Ian; Holroyd, Nancy; Jagels, Kay; Lord, Angela; Moule, Sharon; Mungall, Karen; Norbertczak, Halina; Quail, Michael A.; Rabbinowitsch, Ester; Walker, Danielle; White, Brian; Whitehead, Sally; Small, Pamela L.C.; Brosch, Roland; Ramakrishnan, Lalita; Fischbach, Michael A.; Parkhill, Julian; Cole, Stewart T.
Mycobacterium marinum, a ubiquitous pathogen of fish and amphibia, is a near relative of Mycobacterium tuberculosis, the etiologic agent of tuberculosis in humans. The genome of the M strain of M. marinum comprises a 6,636,827-bp circular chromosome with 5424 CDS, 10 prophages, and a 23-kb mercury-resistance plasmid. Prominent features are the very large number of genes (57) encoding polyketide synthases (PKSs) and nonribosomal peptide synthases (NRPSs) and the most extensive repertoire yet reported of the mycobacteria-restricted PE and PPE proteins, and related-ESX secretion systems. Some of the NRPS genes comprise a novel family and seem to have been acquired horizontally. M. marinum is used widely as a model organism to study M. tuberculosis pathogenesis, and genome comparisons confirmed the close genetic relationship between these two species, as they share 3000 orthologs with an average amino acid identity of 85%. Comparisons with the more distantly related Mycobacterium avium subspecies paratuberculosis and Mycobacterium smegmatis reveal how an ancestral generalist mycobacterium evolved into M. tuberculosis and M. marinum. M. tuberculosis has undergone genome downsizing and extensive lateral gene transfer to become a specialized pathogen of humans and other primates without retaining an environmental niche. M. marinum has maintained a large genome so as to retain the capacity for environmental survival while becoming a broad host range pathogen that produces disease strikingly similar to M. tuberculosis. The work described herein provides a foundation for using M. marinum to better understand the determinants of pathogenesis of tuberculosis. PMID:18403782
Bigi, Fabiana; Garcia-Pelayo, M Carmen; Nuñez-García, Javier; Peralta, Andrea; Caimi, Karina C; Golby, Paul; Hinds, Jason; Cataldi, Angel; Gordon, Stephen V; Romano, Maria I
Tuberculosis in seals is caused by Mycobacterium pinnipedii, a member of the Mycobacterium tuberculosis complex. In this study, we evaluated the extent of genetic variability among Mycobacterium bovis and M. pinnipedii by microarray-based comparative genomics. We identified two deletions that are exclusive to M. pinnipedii: PiD1 that removes the orthologues of the M. tuberculosis genes Rv3530c and Rv3531c, and PiD2 that encompasses genes Rv1977 and Rv1978. Interestingly, a deletion overlapping the previously described RD2 region was identified in some isolates of Mycobacterium microti and further characterised.
Kanaji, Nobuhiro; Kushida, Yoshio; Bandoh, Shuji; Ishii, Tomoya; Haba, Reiji; Tadokoro, Akira; Watanabe, Naoki; Takahama, Takayuki; Kita, Nobuyuki; Dobashi, Hiroaki; Matsunaga, Takuya
Male, 83 FINAL DIAGNOSIS: Membranous glomerulonephritis Symptoms: Producting cough Medication: - Clinical Procedure: - Specialty: Nephrology. Rare disease. Membranous glomerulonephritis can occur secondarily from infectious diseases. There are no reports describing membranous glomerulonephritis caused by non-tuberculous mycobacterium infection. However, several cases with membranous glomerulonephritis due to Mycobacterium tuberculosis have been reported. Mycobacterium shimoidei is an uncommon pathogen, and less than 20 cases with this species have been reported. A therapeutic regimen for this infection has not been established yet. An 83-year-old Japanese man presented with productive cough for 6 months. Computed tomography scan showed multiple cavities in the bilateral pulmonary fields. Acid-fast bacilli were evident in his sputum by Ziehl-Neelsen staining (Gaffky 3). PCR amplifications for Mycobacterium tuberculosis, Mycobacterium avium, and Mycobacterium intracellulare were all negative. Finally, Mycobacterium shimoidei was identified by rpoB sequencing and 16S rRNA sequencing. Urine examination showed a sub-nephrotic range of proteinuria and histology of the kidney showed membranous glomerulonephritis. Antimycobacterial treatment with clarithromycin, rifampicin, and ethambutol dramatically improved not only the pulmonary disease, but also the proteinuria. To the best of our knowledge, the presented case is the first report showing non-tuberculous mycobacterium-induced secondary membranous glomerulonephritis. A combination with clarithromycin, ethambutol, and rifampicin might be effective for treatment of Mycobacterium shimoidei infection.
... in the diagnosis of tuberculosis and provides epidemiological information on this disease. Mycobacterium tuberculosis is the common causative organism in human tuberculosis, a chronic infectious disease...
... in the diagnosis of tuberculosis and provides epidemiological information on this disease. Mycobacterium tuberculosis is the common causative organism in human tuberculosis, a chronic infectious disease...
... in the diagnosis of tuberculosis and provides epidemiological information on this disease. Mycobacterium tuberculosis is the common causative organism in human tuberculosis, a chronic infectious disease...
Cayrou, Caroline; Turenne, Christine; Behr, Marcel A; Drancourt, Michel
Mycobacterium avium complex (MAC) currently comprises eight species of environmental and animal-associated, slowly-growing mycobacteria: Mycobacterium avium, Mycobacterium intracellulare, Mycobacterium chimaera, Mycobacterium colombiense, Mycobacterium arosiense , Mycobacterium bouchedurhonense, Mycobacterium marseillense and Mycobacterium timonense. In humans, MAC organisms are responsible for opportunistic infections whose unique epidemiology remains poorly understood, in part due to the lack of a genotyping method applicable to all eight MAC species. In this study we developed multispacer sequence typing (MST), a sequencing-based method, for the genotyping of MAC organisms. An alignment of the genome sequence of M. avium subsp. hominissuis strain 104 and M. avium subsp. paratuberculosis strain K-10 revealed 621 intergenic spacers <1000 bp. From these, 16 spacers were selected that ranged from 300 to 800 bp and contained a number of variable bases, <50 within each of the 16 spacers. Four spacers were successfully PCR-amplified and sequenced in 11 reference strains. Combining the sequence of these four spacers in 106 MAC organisms, including 83 M. avium, 11 M. intracellulare , six M. chimaera, two M. colombiense and one each of M. arosiense, M. bouchedurhonense, M. marseillense and M. timonense, yielded a total of 45 spacer types, with an index of discrimination of 0.94. Each spacer type was specific for a species and certain spacer types were specific for subspecies of M. avium. MST is a new method for genotyping of organisms belonging to any one of the eight MAC species tested in this study.
Nguyen, D-Q; Righini, C; Darouassi, Y; Schmerber, S
Mycobacterium fortuitum, a rapidly growing non-tuberculous atypical mycobacterium, is commonly found in soil and water. This organism generally causes skin, bone, and soft tissue infections following local trauma or surgical procedures, and in immunodeficient patients. The case reported here is, to our knowledge, the first published report of M. fortuitum nasal infection. The authors report the case of a 3-year-old girl with intranasal tumour-like swelling associated with cervical lymph nodes due to M. fortuitum infection. A combination of radical surgical debridement and prolonged therapy with several antimicrobial agents was required to completely eradicate the infection. This case report indicates that non-tuberculous mycobacterial infections should be considered after failure of conventional antibiotic therapy or when classical microbiological tests fail to identify the pathogen responsible for sinonasal and cervical infections. Copyright © 2011 Elsevier Masson SAS. All rights reserved.
Midani, S; Rathore, M H
Mycobacterium fortuitum is one of the rapidly growing mycobacteria found in soil, dust, and water. It can be isolated as a normal colonizing organism, but as a pathogen this organism causes mainly skin and soft tissue infection preceded by trauma. A wide variety of infections can occur in individuals with predisposing conditions. Central nervous system infection with M fortuitum is rare, and meningitis occurs after surgery or trauma. We believe that ventriculoperitoneal (VP) shunt infection with this organism has not been reported in the literature. Practitioners should be aware of this rare entity and should suspect it in the presence of cerebrospinal fluid pleocytosis with sterile culture, and after trauma, surgery, or manipulation of the VP shunt hardware. Mycobacterium fortuitum is resistant to most first-line and second-line antituberculous drugs, and treatment should include surgical debridement in addition to prolonged antimicrobial therapy.
Lessing, M P; Walker, M M
Environmental (atypical, opportunist, other) mycobacteria were first isolated nearly a century ago. The classification of these "other than Mycobacterium tuberculosis" organisms was initially chaotic until Runyon proposed a scheme of four groups in 1959. Mycobacterium fortuitum is a member of group IV: Rapid growers. These ubiquitous terrestrial and aquatic forms contaminate water supplies, reagents, and clinical samples. They may colonise the respiratory systems of patients whose local defence mechanisms have been impaired or those with congenital and acquired immune defects. They can also cause disease in immunocompetent individuals. There have been fewer than 20 published cases of pulmonary infection caused by M fortuitum. A further case is reported of fatal pulmonary infection in an elderly patient with long standing chronic obstructive airways disease (COAD). He had left upper zone shadowing on chest radiography and lung abscesses at post mortem examination yielded only M fortuitum. PMID:8463423
Marshall, Henry M; Carter, Robyn; Torbey, Matthew J; Minion, Sharri; Tolson, Carla; Sidjabat, Hanna E; Huygens, Flavia; Hargreaves, Megan; Thomson, Rachel M
Mycobacterium lentiflavum, a slow-growing nontuberculous mycobacterium, is a rare cause of human disease. It has been isolated from environmental samples worldwide. To assess the clinical significance of M. lentiflavum isolates reported to the Queensland Tuberculosis Control Centre, Australia, during 2001-2008, we explored the genotypic similarity and geographic relationship between isolates from humans and potable water in the Brisbane metropolitan area. A total of 47 isolates from 36 patients were reported; 4 patients had clinically significant disease. M. lentiflavum was cultured from 13 of 206 drinking water sites. These sites overlapped geographically with home addresses of the patients who had clinically significant disease. Automated repetitive sequence-based PCR genotyping showed a dominant environmental clone closely related to clinical strains. This finding suggests potable water as a possible source of M. lentiflavum infection in humans.
Salas, Natalie Mariam; Klein, Nicole
Abstract Mycobacterium goodii, a rapidly growing nontuberculous mycobacterium, is an emerging pathogen in nosocomial infections. Its inherent resistance patterns make it a challenging organism to treat, and delays in identification can lead to poor outcomes. We present a case of cardiac device pocket infection with M. goodii, complicated by both antibiotic resistance and drug reactions that highlight the challenges faced by clinicians trying to eradicate these infections. We also present a brief review of the English literature surrounding this disease, including a table of all reported cases of M. goodii infections and their outcomes to act as guide for clinicians formulating treatment plans for these infections. A clear understanding of diagnostic methods and treatment caveats is essential to curing infections caused by these organisms.
Leissinger, M K; Garber, J B; Fowlkes, N; Grooters, A M; Royal, A B; Gaunt, S D
A 1-year old female spayed German Shepherd dog was evaluated for acute onset of dyspnea. Pyogranulomatous inflammation and green globoid structures were present on aspirates of the affected lung. Impression smears and histopathology confirmed pyogranulomatous pneumonia, with large amounts of lipid corresponding to the green structures noted cytologically, and identified poorly staining bacterial rods within lipid vacuoles. Special stains confirmed the presence of acid-fast bacterial rods, and polymerase chain reaction and DNA sequencing identified the organism as Mycobacterium fortuitum. M. fortuitum pneumonia is well described in humans and has previously been reported in 4 dogs and 1 cat. Lipid was a prominent cytologic and histologic feature, as is often described in humans and in the single feline case report. Additionally, this case highlights the variable cytologic appearance of lipid, as well as Mycobacterium spp, which are classically nonstaining with Wright-Giemsa.
Bailey, Mai Ann; Na, Hana; Duthie, Malcolm S.; Gillis, Thomas P.; Lahiri, Ramanuj
Nitazoxanide (NTZ) is an anti-parasitic drug that also has activity against bacteria, including Mycobacterium tuberculosis. Our data using both radiorespirometry and live-dead staining in vitro demonstrate that NTZ similarly has bactericidal against M. leprae. Further, gavage of M. leprae-infected mice with NTZ at 25mg/kg provided anti-mycobacterial activity equivalent to rifampicin (RIF) at 10 mg/kg. This suggests that NTZ could be considered for leprosy treatment. PMID:28850614
Chowdhury, Haziq Raees; Comyn, Oliver; Jones, Gill; Nanavaty, Mayank A
Atypical mycobacterial infections of the cornea can present with nonspecific inflammatory changes and graft rejection, with no obvious focus to culture and a subsequent delay to diagnosis. These pathogens are well documented in the literature following laser-assisted in situ keratomileusis but have rarely been described following corneal transplant surgery. We report a single case of Mycobacterium chelonae keratitis 1 year after tectonic keratoplasty.
Borelli, Violetta; Banfi, Elena; Perrotta, Maria Giovanna; Zabucchi, Giuliano
We investigated the antimycobacterial role of myeloperoxidase (MPO), one of the most abundant granule proteins in human neutrophils. Our data indicate that purified MPO, in the presence of hydrogen peroxide, exerts a consistent killing activity against Mycobacterium tuberculosis H37Rv and against a clinical isolate. The activity is time and dose dependent and requires the presence of chloride ions in the assay medium. PMID:10417186
Korb, Vanessa C.; Chuturgoon, Anil A.; Moodley, Devapregasan
Mycobacterium tuberculosis (MTB) is one of the most successful pathogens in human history and remains a global health challenge. MTB has evolved a plethora of strategies to evade the immune response sufficiently to survive within the macrophage in a bacterial-immunological equilibrium, yet causes sufficient immunopathology to facilitate its transmission. This review highlights MTB as the driver of disease pathogenesis and presents evidence of the mechanisms by which MTB manipulates the protective immune response into a pathological productive infection. PMID:26927066
Vera-Cabrera, Lucio; Ramos-Alvarez, Jessica; Molina-Torres, Carmen A; Rivera-Morales, Lydia Guadalupe; Rendón, Adrian; Quiñones-Falconi, Francisco; Ocampo-Candiani, Jorge
In the present work, we studied the genetic diversity of Mycobacterium tuberculosis clinical isolates from patients according to their gender, age, and geographic location in Mexico. We did not observe any statistically significant differences in regard to age or gender. We found that spoligo international type 53 (SIT53) is more frequent in the northern states and that SIT119 predominates in central Mexico. Copyright © 2014, American Society for Microbiology. All Rights Reserved.
Engbaek, H C; Thormann, J; Vergmann, B
Mycobacterium marinum was isolated for the first time in Denmark from skin granuloma of a 37-year-old man. The skin lesion was provoked by an injury from the broken glass of an aquarium used for tropical fish. Treatment with rifampicin and ethambutol was successful. At the time of diagnosis, M. marinum was also isolated from a dead fish; but in no case was skin granuloma found among purchasers of fish supplied by the patient.
Ramos-Alvarez, Jessica; Molina-Torres, Carmen A.; Rivera-Morales, Lydia Guadalupe; Rendón, Adrian; Quiñones-Falconi, Francisco; Ocampo-Candiani, Jorge
In the present work, we studied the genetic diversity of Mycobacterium tuberculosis clinical isolates from patients according to their gender, age, and geographic location in Mexico. We did not observe any statistically significant differences in regard to age or gender. We found that spoligo international type 53 (SIT53) is more frequent in the northern states and that SIT119 predominates in central Mexico. PMID:24850349
Johnson, Benjamin K; Abramovitch, Robert B
Mycobacterium tuberculosis colonizes, survives, and grows inside macrophages. In vitro macrophage infection models, using both primary macrophages and cell lines, enable the characterization of the pathogen response to macrophage immune pressure and intracellular environmental cues. We describe methods to propagate and infect primary murine bone marrow-derived macrophages and J774 and THP-1 macrophage-like cell lines. We also present methods on the characterization of M. tuberculosis intracellular survival and the preparation of infected macrophages for imaging.
Yujiao, Zhang; Xiaojing, Li; Kaixia, Mi
Tuberculosis, caused by the pathogen Mycobacterium tuberculosis, is one of the world's deadliest bacterial infectious disease. It is still a global-health threat, particularly because of the drug-resistant forms. Fluoroquinolones, with target of gyrase, are among the drugs used to treat tuberculosis. However, their widespread use has led to bacterial resistance. The molecular mechanisms of fluoroquinolone resistance in mycobacterium tuberculosis have been reported, such as DNA gyrase mutations, drug efflux pumps system, bacterial cell wall thickness and pentapeptide proteins (MfpA) mediated regulation of gyrase. Mutations in gyrase conferring quinolone resistance play important roles and have been extensively studied. Recent studies have shown that the regulation of DNA gyrase affects mycobacterial drug resistance, but the mechanisms, especially by post-translational modification and regulatory proteins, are poorly understood. In this review, we summarize the fluoroquinolone drug development, and the molecular genetics of fluoroquinolone resistance in mycobacteria. Comprehensive understanding of the mechanisms of fluoroquinolone resistance in Mycobacterium tuberculosis will open a new view on understanding drug resistance in mycobacteria and lead to novel strategies to develop new accurate diagnosis methods.
Realini, L.; De Ridder, K.; Palomino, J.-C.; Hirschel, B.; Portaels, F.
Our studies show that microaerophilic conditions promote the growth of Mycobacterium genavense in semisolid medium. The growth of M. genavense at 2.5 or 5% oxygen was superior to that obtained at 21% oxygen in BACTEC primary cultures (Middlebrook 7H12, pH 6.0, without additives). By using nondecontaminated specimens, it was possible to detect growth with very small inocula (25 bacilli/ml) of 12 different M. genavense strains (from nude mice) within 6 weeks of incubation under low oxygen tension; conversely, with 21% oxygen, no growth of 8 of 12 (66.7%) M. genavense strains was detected (growth index, <10). The same beneficial effect of 2.5 or 5% oxygen was observed in primary cultures of a decontaminated clinical specimen. Low oxygen tension (2.5 or 5%) is recommended for the primary isolation of M. genavense. Microaerophilic cultivation of other atypical mycobacteria, especially slow-growing (e.g., Mycobacterium avium) and difficult-to-grow (e.g., Mycobacterium ulcerans) species, is discussed. PMID:9705393
Masso, F; Paez, A; Varela, E; d Diaz; Zenteno, E; Montano, L
BACKGROUND—The mechanism of Mycobacterium tuberculosis penetration into tissues is poorly understood but it is reasonable to assume that there is a contribution from proteases capable of disrupting the extracellular matrix of the pulmonary epithelium and the blood vessels. A study was undertaken to identify and characterise collagen degrading activity of M tuberculosis. METHODS—Culture filtrate protein extract (CFPE) was obtained from reference mycobacterial strains and mycobacteria isolated from patients with tuberculosis. The collagen degrading activity of CFPE was determined according to the method of Johnson-Wint using 3H-type I collagen. The enzyme was identified by the Birkedal-Hansen and Taylor method and its molecular mass determined by SDS-PAGE and Sephacryl S-300 gel filtration chromatography using an electroelution purified enzyme. RESULTS—CFPE from Mycobacterium tuberculosis strain H37Rv showed collagenolytic activity that was four times higher than that of the avirulent strain H37Ra. The 75 kDa enzyme responsible was divalent cation dependent. Other mycobacterial species and those isolated from patients with tuberculosis also had collagen degrading activity. CONCLUSIONS—Mycobacterium species possess a metalloprotease with collagen degrading activity. The highest enzymatic activity was found in the virulent reference strain H37Rv. PMID:10212111
Garnier, Thierry; Eiglmeier, Karin; Camus, Jean-Christophe; Medina, Nadine; Mansoor, Huma; Pryor, Melinda; Duthoy, Stephanie; Grondin, Sophie; Lacroix, Celine; Monsempe, Christel; Simon, Sylvie; Harris, Barbara; Atkin, Rebecca; Doggett, Jon; Mayes, Rebecca; Keating, Lisa; Wheeler, Paul R.; Parkhill, Julian; Barrell, Bart G.; Cole, Stewart T.; Gordon, Stephen V.; Hewinson, R. Glyn
Mycobacterium bovis is the causative agent of tuberculosis in a range of animal species and man, with worldwide annual losses to agriculture of $3 billion. The human burden of tuberculosis caused by the bovine tubercle bacillus is still largely unknown. M. bovis was also the progenitor for the M. bovis bacillus Calmette–Guérin vaccine strain, the most widely used human vaccine. Here we describe the 4,345,492-bp genome sequence of M. bovis AF2122/97 and its comparison with the genomes of Mycobacterium tuberculosis and Mycobacterium leprae. Strikingly, the genome sequence of M. bovis is >99.95% identical to that of M. tuberculosis, but deletion of genetic information has led to a reduced genome size. Comparison with M. leprae reveals a number of common gene losses, suggesting the removal of functional redundancy. Cell wall components and secreted proteins show the greatest variation, indicating their potential role in host–bacillus interactions or immune evasion. Furthermore, there are no genes unique to M. bovis, implying that differential gene expression may be the key to the host tropisms of human and bovine bacilli. The genome sequence therefore offers major insight on the evolution, host preference, and pathobiology of M. bovis. PMID:12788972
Patel, Trisha; Scroggins-Markle, Leslie; Kelly, Brent
Background. Dermal piercings have recently become a fashion symbol. Common complications include hypertrophic scarring, rejection, local infection, contact allergy, and traumatic tearing. We report a rare case of Mycobacterium fortuitum following a dermal piercing and discuss its medical implications and treatments. Case. A previously healthy 19-year-old woman presented complaining of erythema and edema at the site of a dermal piercing on the right fourth dorsal finger. She was treated with a 10-day course of trimethoprim-sulfamethoxazole and one course of cephalexin by her primary care physician with incomplete resolution. The patient stated that she had been swimming at a local water park daily. A punch biopsy around the dermal stud was performed, and cultures with sensitivities revealed Mycobacterium fortuitum. The patient was treated with clarithromycin and ciprofloxacin for two months receiving full resolution. Discussion. Mycobacterium fortuitum is an infrequent human pathogen. This organism is a Runyon group IV, rapidly growing nontuberculous mycobacteria, often found in water,soil, and dust. Treatment options vary due to the size of the lesion. Small lesions are typically excised, while larger lesions require treatment for 2-6 months with antibiotics. We recommend a high level of suspicion for atypical mycobacterial infections in a piercing resistant to other therapies.
Cynamon, Michael; Jureller, Jeff; Desai, Balaji; Ramachandran, Krithika; Sklaney, Mary; Grossman, Trudy H
The in vitro activities of TP-271, a novel fluorocycline antimicrobial, against 22 isolates of Mycobacterium abscessus, 22 isolates of Mycobacterium fortuitum, and 19 isolates of Nocardia spp. were studied by a microtiter broth dilution method. The MIC(90)s for M. abscessus, M. fortuitum, and Nocardia spp. were 0.5 μg/ml, 0.03 μg/ml, and 8 μg/ml, respectively. TP-271 was significantly more active than the respective control drug in virtually all tests.
including Mycobacterium tuberculosis, Mycobacterium leprae , Staphylococcusaureus, Pseudomonas aeruginosa, Escherichia coli, enterococ----ci, Neissr•~n...97 SAD "Treatment of Mycobacterium intracellulare Infected Mice with Walter Reed Compound H" Final Comprehensive Report J. Kenneth McClatchy, Ph.D...REPORT & PERIOD COVERED "TREATMENT OF MYCOBACTERIUM INTRACELLULARE - Final Comprehensive Report INFECTED MICE WITH WALTER REED COMPOUND H"li G
Springer, B; Tortoli, E; Richter, I; Grünewald, R; Rüsch-Gerdes, S; Uschmann, K; Suter, F; Collins, M D; Kroppenstedt, R M; Böttger, E C
A new type of slowly growing, nonphotochromogenic mycobacterium was recovered from two patients with disseminated disease. The growth characteristics, acid fastness, acids were consistent with those for Mycobacterium species. The results of biochemical investigations, lipid analyses, and comparative 16S rRNA sequencing showed that these isolates represent a new slowly growing Mycobacterium species which is named Mycobacterium conspicuum. PMID:8576323
Jaworski, Radosław; Naumiuk, Łukasz; Paczkowski, Konrad; Formella, Danuta; Pek, Renata; Zieliński, Jacek; Haponiuk, Ireneusz
An outbreak of invasive Mycobacterium chimaera infections associated with "heater-cooler" devices in patients treated with cardiac surgery has been described worldwide. The authors summarize the current state of knowledge regarding the epidemiology, diagnostics, treatment, and prevention of Mycobacterium chimaera infections in patients after cardiothoracic surgery.
... Tuberculosis; Meeting The National Institute for Occupational Safety and Health (NIOSH) of the Centers for... Airborne Mycobacterium Tuberculosis. Time and Date: 1 p.m.-5 p.m., March 29, 1994. Place: Alice Hamilton... peer review of a NIOSH project entitled ``Method Development For Airborne Mycobacterium...
Tortoli, E; Kirschner, P; Bartoloni, A; Burrini, C; Manfrin, V; Mantella, A; Scagnelli, M; Scarparo, C; Simonetti, M T; Böttger, E C
A mycobacterium isolated from a clinical sample of an AIDS patient was identified as Mycobacterium interjectum by direct 16S rRNA sequence determination. High-performance liquid chromatography, however, revealed a mycolic acid pattern which was different from the one shared by the previously analyzed strains of this species. PMID:8862610
We report the draft genome sequence of the type strain Mycobacterium chimaera Fl-0169T, a member of the Mycobacterium avium complex (MAC). M. chimaera Fl-0169T was isolated from a patient in Italy and is highly similar to strains of M. chimaera isolated in Ireland, though Fl-016...
Tokarev, Vasily; Kessler, Collin; McLimans, Christopher; Gomez-Alvarez, Vicente; Wright, Justin; King, Dawn; Lamendella, Regina
ABSTRACT We report here the draft genome sequence of the type strain Mycobacterium chimaera Fl-0169, a member of the Mycobacterium avium complex (MAC). M. chimaera Fl-0169T was isolated from a patient in Italy and is highly similar to strains of M. chimaera isolated in Ireland, although Fl-0169T possesses unique virulence genes. PMID:28232435
Goldenberg, Oliver; Richter, Elvira; Göbel, Ulf B.; Petrich, Annette; Buchholz, Petra; Moter, Annette
Retrospective molecular genetic analysis of 166 Mycobacterium intracellulare isolates showed that 143 (86%) strains could be assigned to Mycobacterium chimaera sp. nov. Of 97 patients from whom M. chimaera sp. nov. was isolated, only 3.3% exhibited mycobacterial lung disease, whereas all M. intracellulare isolates caused severe pulmonary infections. PMID:18760016
Schweickert, Birgitta; Goldenberg, Oliver; Richter, Elvira; Göbel, Ulf B; Petrich, Annette; Buchholz, Petra; Moter, Annette
Retrospective molecular genetic analysis of 166 Mycobacterium intracellulare isolates showed that 143 (86%) strains could be assigned to Mycobacterium chimaera sp. nov. Of 97 patients from whom M. chimaera sp. nov. was isolated, only 3.3% exhibited mycobacterial lung disease, whereas all M. intracellulare isolates caused severe pulmonary infections.
Tsouh Fokou, Patrick Valere; Nyarko, Alexander Kwadwo; Appiah-Opong, Regina; Tchokouaha Yamthe, Lauve Rachel; Ofosuhene, Mark; Boyom, Fabrice Fekam
Mycobacterium ulcerans disease has been a serious threat for people living in rural remote areas. Due to poverty or availability of traditional medicine these populations rely on herbal remedies. Currently, data on the anti-Mycobacterium ulcerans activity of plants, so far considered community-based knowledge, have been scientifically confirmed, concomitantly with some medicinal plants used to treat infectious diseases in general. Products derived from plants usually responsible for the biological properties may potentially control Mycobacterium ulcerans disease; numerous studies have aimed to describe the chemical composition of these plant antimicrobials. Thus, the present work provides the first compilation of medicinal plants that demonstrated inhibitory potential on Mycobacterium ulcerans. This work shows that the natural products represent potential alternatives to standard therapies for use as curative medicine for Mycobacterium ulcerans disease. PMID:26779539
Sevim, P; Ozer, S; Rad, F
Ichthyozoonotic Mycobacterium spp. poses health risks both to fish and humans. In this study, the presence of ichthyozoonotic Mycobacterium spp. was investigated in red mullet (Mullus barbatus barbatus) and surmullet (Mullus surmuletus), widely caught species in the Mediterranean and the Aegean Sea. A total of 208 fish samples, provided from fishermen of Mersin province (Turkey) were studied. Using conventional methods, Mycobacterium spp. was isolated and identified at the genus level by PCR and at the species level by PCR-RFLP. Thirteen Mycobacterium spp. were detected in 13 (6.25%) fish samples. Four mycobacteria were identified as M. genavense, three as M. fortuitum, three as M. scrofulaceum, one as M. marinum, one as M. vaccae and one as M. aurum. No signs of mycobacteriosis were observed in fish samples. Findings of this study can contribute to future studies of onichthyozoonotic Mycobacterium spp. in seafood. PMID:27175166
Messelhäusser, U; Kämpf, P; Hörmansdorfer, S; Wagner, B; Schalch, B; Busch, U; Höller, C; Wallner, P; Barth, G; Rampp, A
A combined molecular and cultural method for the detection of the Mycobacterium tuberculosis complex (MTBC) and Mycobacterium avium subsp. paratuberculosis was developed and tested with artificially contaminated milk and dairy products. Results indicate that the method can be used for a reliable detection as a basis for first risk assessments.
Shepard, C C; Youmans, A Y; Youmans, G P
Mycobacterial ribonucleic acid preparations from H37Ra, an attenuated strain of Mycobacterium tuberculosis, provide their usual marked protection against M. tuberculosis challenge; however, they provided no protection against Mycobacterium leprae challenge. Suspensions of intact H37Ra were not effective against M. leprae. Suspensions of BCG gave their usual distinct protection against M. leprae challenge. PMID:404242
Panas, Michael W; Jain, Paras; Yang, Hui; Mitra, Shimontini; Biswas, Debasis; Wattam, Alice Rebecca; Letvin, Norman L; Jacobs, William R
Research on tuberculosis and leprosy was revolutionized by the development of a plasmid transformation system in the fast-growing surrogate, Mycobacterium smegmatis. This transformation system was made possible by the successful isolation of a M. smegmatis mutant strain mc(2)155, whose efficient plasmid transformation (ept) phenotype supported the replication of Mycobacterium fortuitum pAL5000 plasmids. In this report, we identified the EptC gene, the loss of which confers the ept phenotype. EptC shares significant amino acid sequence homology and domain structure with the MukB protein of Escherichia coli, a structural maintenance of chromosomes (SMC) protein. Surprisingly, M. smegmatis has three paralogs of SMC proteins: EptC and MSMEG_0370 both share homology with Gram-negative bacterial MukB; and MSMEG_2423 shares homology with Gram-positive bacterial SMCs, including the single SMC protein predicted for Mycobacterium tuberculosis and Mycobacterium leprae. Purified EptC was shown to bind ssDNA and stabilize negative supercoils in plasmid DNA. Moreover, an EptC-mCherry fusion protein was constructed and shown to bind to DNA in live mycobacteria, and to prevent segregation of plasmid DNA to daughter cells. To our knowledge, this is the first report of impaired plasmid maintenance caused by a SMC homolog, which has been canonically known to assist the segregation of genetic materials.
Kelly, Pamela; Jahns, Hanne; Power, Eugene; Bainbridge, John; Kenny, Kevin; Corpa, Juan M; Cassidy, Joseph P; Callanan, John J
Avian tuberculosis rarely affects ratites compared to other bird species and is typically caused by Mycobacterium avium species. This study describes the pathological and microbiological findings in three adult ostriches with mycobacteriosis, in one of which Mycobacterium bovis was isolated from the lesions. Post mortem examinations on ostriches from two different zoological collections in Ireland revealed multifocal caseous granulomas affecting the spleen and liver in all cases, with additional involvement of intestines in two cases. In one case, granulomas were present within the pharynx, at the thoracic inlet and multifocally on the pleural surface. Acid-fast bacilli were observed in all lesions. Mycobacterium sp. of the M. avium complex was isolated from the intestinal lesions in the two cases with intestinal involvement, and M. bovis sp. oligotype SB0140 was cultured from the liver of the third ostrich. This represents the first reported case of M. bovis infection in an ostrich. Avian tuberculosis due to M. bovis is rare and to date has been reported in only parrots and experimentally inoculated birds. Mycobacterium bovis needs to be considered as a possible cause of tuberculosis in ostriches because the lesions are similar to those observed with M. avium complex infection.
Kaushik, Amit; Makkar, Nayani; Pandey, Pooja; Parrish, Nicole; Singh, Urvashi; Lamichhane, Gyanu
An effective regimen for treatment of tuberculosis (TB) is comprised of multiple drugs that inhibit a range of essential cellular activities in Mycobacterium tuberculosis. The effectiveness of a regimen is further enhanced if constituent drugs act with synergy. Here, we report that faropenem (a penem) or biapenem, doripenem, or meropenem (carbapenems), which belong to the β-lactam class of antibiotics, and rifampin, one of the drugs that forms the backbone of TB treatment, act with synergy when combined. One of the reasons (carba)penems are seldom used for treatment of TB is the high dosage levels required, often at the therapeutic limits. The synergistic combination of rifampin and these (carba)penems indicates that (carba)penems can be administered at dosages that are therapeutically relevant. The combination of faropenem and rifampin also limits the frequency of resistant mutants, as we were unable to obtain spontaneous mutants in the presence of these two drugs. The combinations of rifampin and (carba)penems were effective not only against drug-sensitive Mycobacterium tuberculosis but also against drug-resistant clinical isolates that are otherwise resistant to rifampin. A combination of doripenem or biapenem and rifampin also exhibited synergistic activity against Mycobacterium abscessus. Although the MICs of these three drugs alone against M. abscessus are too high to be of clinical relevance, their concentrations in combinations are therapeutically relevant; therefore, they warrant further evaluation for clinical utility to treat Mycobacterium abscessus infection, especially in cystic fibrosis patients.
Tran, Phuong M; Dahl, John L
Several fast- to intermediate-growing, acid-fast, scotochromogenic bacteria were isolated from Sarracenia purpurea pitcher waters in Minnesota sphagnum peat bogs. Two strains (DL734T and DL739T) were among these isolates. On the basis of 16S rRNA gene sequences, the phylogenetic positions of both strains is in the genus Mycobacterium with no obvious relation to any characterized type strains of mycobacteria. Phenotypic characterization revealed that neither strain was similar to the type strains of known species of the genus Mycobacterium in the collective properties of growth, pigmentation or fatty acid composition. Strain DL734T grew at temperatures between 28 and 32 °C, was positive for 3-day arylsulfatase production, and was negative for Tween 80 hydrolysis, urease and nitrate reduction. Strain DL739T grew at temperatures between 28 and 37 °C, and was positive for Tween 80 hydrolysis, urea, nitrate reduction and 3-day arylsulfatase production. Both strains were catalase-negative while only DL739T grew with 5 % NaCl. Fatty acid methyl ester profiles were unique for each strain. DL739T showed an ability to survive at 8 °C with little to no cellular replication and is thus considered to be psychrotolerant. Therefore, strains DL734T and DL739T represent two novel species of the genus Mycobacterium with the proposed names Mycobacterium sarraceniae sp. nov. and Mycobacterium helvum sp. nov., respectively. The type strains are DL734T (=JCM 30395T=NCCB 100519T) and DL739T (=JCM 30396T=NCCB 100520T), respectively.
Polycyclic aromatic hydrocarbon-degrading species isolated from Hawaiian soils: Mycobacterium crocinum sp. nov., Mycobacterium pallens sp. nov., Mycobacterium rutilum sp. nov., Mycobacterium rufum sp. nov. and Mycobacterium aromaticivorans sp. nov.
Hennessee, Christiane T; Seo, Jong-Su; Alvarez, Anne M; Li, Qing X
Polycyclic aromatic hydrocarbons (PAHs) are widespread environmental contaminants. In this study, both pristine and contaminated soils were sampled as a source of PAH-degrading organisms. Nine strains isolated from these soils were identified as rapidly growing members of the genus Mycobacterium through basic phenotypic characteristics and through sequence similarity of three genes. Because the sequence similarity of the 16S rRNA gene is relatively high among members of this genus, additional conserved genes encoding the beta subunit of RNA polymerase (rpoB) and a heat-shock protein (hsp65) were sequenced. Several analyses were completed to differentiate the strains from one another and to determine their species-level taxonomy, including fatty acid methyl ester analysis, biochemical tests and substrate-utilization profiling. A phylogenetic tree incorporating sequences for all three genes was constructed with the isolates and their close described relatives. Results for biochemical tests, substrate-utilization tests and DNA sequencing were compared with those of the phylogenetically similar organisms to establish the isolated strains as representatives of novel species with characteristics unlike those of previously described species of Mycobacterium. Finally, DNA-DNA hybridization was performed between strains and their close relatives to confirm their position within novel species. Our results demonstrated that the isolates represent five novel species, which were named Mycobacterium crocinum sp. nov. (type strain czh-42(T) =ATCC BAA-1373(T) =CIP 109262(T); reference strains czh-1A =ATCC BAA-1370 =CIP 109266 and czh-3 =ATCC BAA-1371=CIP 109267), Mycobacterium pallens sp. nov. (type strain czh-8(T) =ATCC BAA-1372(T) =CIP 109268(T)), Mycobacterium rutilum sp. nov. (type strain czh-117(T) =ATCC BAA-1375(T) =CIP 109271(T); reference strains czh-107 =ATCC BAA-1374 =CIP 109270 and czh-132 =ATCC BAA-1376 =CIP 109272), Mycobacterium rufum sp. nov. (type strain JS14(T
Liu, Minqiang; Li, Wu; Xiang, Xiaohong; Xie, Jianping
Tuberculosis remains a serious human public health concern. The coevolution between its pathogen Mycobacterium tuberculosis and human host complicated the way to prevent and cure TB. Apoptosis plays subtle role in this interaction. The pathogen endeavors to manipulate the apoptosis via diverse effectors targeting key signaling nodes. In this paper, we summarized the effectors pathogen used to subvert the apoptosis, such as LpqH, ESAT-6/CFP-10, LAMs. The interplay between different forms of cell deaths, such as apoptosis, autophagy, necrosis, is also discussed with a focus on the modes of action of effectors, and implications for better TB control.
Yang, Kai; Samplaski, Mary; Mazzulli, Tony; Lo, Kirk; Grober, Ethan; Jarvi, Keith Allen
A 65-year-old healthy woman presented with persistent, asymptomatic sterile pyuria detected by her family physician. While she did not have symptoms, the patient recounts that she has had cloudy urine for years. Cultures of the urine for bacteria showed no growth and no fungi were identified. First-morning urine samples were sent for both tuberculosis and nontuberculosis mycobacterium species testing. The culture grew genotypically identified Mycobaterium avium complex (MAC). Mantoux skin testing was positive. No urological abnormalities were detected by ultrasound and computed tomography (CT) imaging of the urinary tract. PMID:27790302
Filliol, Ingrid; Driscoll, Jeffrey R.; van Soolingen, Dick; Kreiswirth, Barry N.; Kremer, Kristin; Valétudie, Georges; Anh, Dang Duc; Barlow, Rachael; Banerjee, Dilip; Bifani, Pablo J.; Brudey, Karin; Cataldi, Angel; Cooksey, Robert C.; Cousins, Debby V.; Dale, Jeremy W.; Dellagostin, Odir A.; Drobniewski, Francis; Engelmann, Guido; Ferdinand, Séverine; Gascoyne-Binzi, Deborah; Gordon, Max; Gutierrez, M. Cristina; Haas, Walter H.; Heersma, Herre; Källenius, Gunilla; Kassa-Kelembho, Eric; Koivula, Tuija; Ly, Ho Minh; Makristathis, Athanasios; Mammina, Caterina; Martin, Gerald; Moström, Peter; Mokrousov, Igor; Narbonne, Valérie; Narvskaya, Olga; Nastasi, Antonino; Niobe-Eyangoh, Sara Ngo; Pape, Jean W; Rasolofo-Razanamparany, Voahangy; Ridell, Malin; Rossetti, M. Lucia; Stauffer, Fritz; Suffys, Philip N.; Takiff, Howard; Texier-Maugein, Jeanne; Vincent, Véronique; de Waard, Jacobus H.
We present a short summary of recent observations on the global distribution of the major clades of the Mycobacterium tuberculosis complex, the causative agent of tuberculosis. This global distribution was defined by data-mining of an international spoligotyping database, SpolDB3. This database contains 11,708 patterns from as many clinical isolates originating from more than 90 countries. The 11,708 spoligotypes were clustered into 813 shared types. A total of 1,300 orphan patterns (clinical isolates showing a unique spoligotype) were also detected. PMID:12453368
Balsam, Leora B; Louie, Eddie; Hill, Fred; Levine, Jamie; Phillips, Michael S
A global outbreak of invasive Mycobacterium chimaera infections after cardiac surgery has recently been linked to bioaerosols from contaminated heater-cooler units. The majority of cases have occurred after valvular surgery or aortic graft surgery and nearly half have resulted in death. To date, infections in patients with left ventricular assist devices (LVADs) have not been characterized in the literature. We report two cases of device-associated M. chimaera infection in patients with continuous-flow LVADs and describe challenges related to diagnosis and management in this population. © 2017 Wiley Periodicals, Inc.
Riera, Jaume; Conesa, Xavier; Pisa, Jose; Moreno, Josefa; Siles, Eduard; Novell, Josep
The incidence of infection by Mycobacterium marinum is rising, mainly due to the increasing popularity of home aquariums. The infection typically manifests as skin lesions, with septic arthritis being a rare presentation form. The disease is difficult to diagnose even when there is a high clinical suspicion, as culture in specific media may not yield positive findings. Thus, establishment of appropriate treatment is often delayed. Synovectomy, capsular thinning, and joint drainage together with prolonged, combined antibiotic therapy may be needed to cure the infection.
Russell, David G; VanderVen, Brian C; Lee, Wonsik; Abramovitch, Robert B; Kim, Mi-jeong; Homolka, Susanne; Niemann, Stefan; Rohde, Kyle H
Mycobacterium tuberculosis remains one of the most pernicious of human pathogens. Current vaccines are ineffective, and drugs, although efficacious, require prolonged treatment with constant medical oversight. Overcoming these problems requires a greater appreciation of M. tuberculosis in the context of its host. Upon infection of either macrophages in culture or animal models, the bacterium realigns its metabolism in response to the new environments it encounters. Understanding these environments, and the stresses that they place on M. tuberculosis, should provide insights invaluable for the development of new chemo- and immunotherapeutic strategies.
Marsollier, Laurent; Sévérin, Tchibozo; Aubry, Jacques; Merritt, Richard W; Saint André, Jean-Paul; Legras, Pierre; Manceau, Anne-Lise; Chauty, Annick; Carbonnelle, Bernard; Cole, Stewart T
Accumulative indirect evidence of the epidemiology of Mycobacterium ulcerans infections causing chronic skin ulcers (i.e., Buruli ulcer disease) suggests that the development of this pathogen and its transmission to humans are related predominantly to aquatic environments. We report that snails could transitorily harbor M. ulcerans without offering favorable conditions for its growth and replication. A novel intermediate link in the transmission chain of M. ulcerans becomes likely with predator aquatic insects in addition to phytophage insects. Water bugs, such as Naucoris cimicoides, a potential vector of M. ulcerans, were shown to be infected specifically by this bacterium after feeding on snails experimentally exposed to M. ulcerans.
Mycobacterium neoaurum (M. neoaurum) is an infrequently encountered cause of infection in humans. It is a member of the rapidly growing mycobacteria family. It predominately afflicts those with a compromised immune status and a chronically indwelling vascular access. Isolation of this organism is challenging yet the advent of 16s ribosomal sequencing paved the way for more sensitive detection. No treatment guidelines are available and treatment largely depends on the experience of the treating physician and nature of the isolate. We report a case of M. neoaurum bacteremia in an immune competent host, with a chronically placed peripherally inserted central catheter (PICC line). PMID:27807489
Imwidthaya, P; Suthiravitayavaniz, K; Phongpanich, S
This research was designed to isolate Mycobacterium other than tubercle bacilli in various environments in the Bangkok area, in 1987. The results were as follows, one hundred samples of soil yielded 1 Mycobacterium gordonae, 2 M. chelonei, 57 M. fortuitum, 1 Nocardia asteroides, one hundred samples of natural water from the Chao Phraya River and the canals of Chao Phraya River yielded 2 M. chelonei, 18 M. fortuitum, 1 N. asteroides and 1 N. brasiliensis, thirty samples of tap water yielded 3 M. gordonae. But thirty samples of water from swimming pools were negative for Mycobacterium.
Hod, T; Kushnir, R; Paitan, Y; Korzets, Z
Mycobacterium fortuitum group species is an atypical rapidly growing nontuberculous mycobacterium. It has been increasingly recognized as a potential pathogen mostly encountered in skin and soft tissue infections. Rarely, however, it has been associated with catheter-related infections, either central venous lines or peritoneal dialysis catheters. In this report we describe 2 patients maintained on continuous ambulatory peritoneal dialysis who developed Mycobacterium fortuitum peritonitis and a catheter tunnel abscess, respectively. Molecular biology identification of the isolates was performed in both cases. The literature is reviewed regarding all similar cases.
Hagiwara, Eri; Sekine, Akimasa; Sato, Tomohide; Baba, Tomohisa; Shinohara, Takeshi; Endo, Takahiro; Sogo, Yoko; Nishihira, Ryuichi; Komatsu, Shigeru; Matsumoto, Yutaka; Ogura, Takashi; Takahashi, Hiroshi
A 39-year-old man with dyspnea was revealed to have severe pneumothorax and received partial resection of the left upper lobe after unsuccessful drainage. Necrotizing epitheloid granuloma was found in the resected lung and Mycobacterium fortuitum was detected from the lesion. Chemotherapy with levofloxacin and clarithromycin was started one year after surgery because of the newly found nodular shadow near the lesion. The case experienced pyothorax due to pulmonary tuberculosis three years before and Mycobacterium avium pleuritis one year before this episode. Three-time mycobacterial pleural infection in three years seems to be uncommon. Furthermore this is the first report of pneumothorax associated with pulmonary Mycobacterium fortuitum infection.
Cellone, S. A.
Se efectuaron algunas pruebas con la cámara CCD (+ Reductor Focal) instalada en el foco Cassegrain del Telescopio de 2.15 m del Complejo Astronómico El Leoncito (CASLEO). Las conclusiones más significativas son: Los tiempos de exposición efectivos difieren de los nominales en una fracción apreciable de segundo. En exposiciones de menos de 3 segundos, la iluminación no es pareja en todo el detector. En consecuencia, se recomiendan los pasos a seguir por los astrónomos tanto durante la observación como en la reducción de sus datos.
Aziz, Dinah Binte; Low, Jian Liang; Wu, Mu-Lu; Gengenbacher, Martin; Teo, Jeanette W P; Dartois, Véronique; Dick, Thomas
Lung infections with Mycobacterium abscessus are emerging as a global threat to individuals with cystic fibrosis and other patient groups. Recent evidence for human-to-human transmission worsens the situation. M. abscessus is an intrinsically multidrug resistant pathogen showing resistance even against standard anti tuberculosis drugs such as rifampicin. Here, our objective was to identify existing drugs that may be employed for the treatment of M. abscessus lung disease. A collection of more than 2700 approved drugs was screened at a single point concentration against an M. abscessus clinical isolate. Hits were confirmed with fresh solids in dose response experiments. For the most attractive hit, growth inhibition and bactericidal activities against reference strains of the three M. abscessus subspecies and a collection of clinical isolates were determined. Surprisingly, the rifampicin derivative rifabutin had an MIC of 3 ± 2 μM (3 μg/mL) against the screening strain, the reference strains M. abscessus subsp. abscessus ATCC 19977, M. abscessus subsp. bolletii CCUG 50184-T and M. abscesuss subsp. massiliense CCUG 48898-T, as well as a collection of clinical isolates. Furthermore, rifabutin was active against clarithromycin resistant strains. In conclusion, rifabutin - in contrast to rifampicin - is active against the Mycobacterium abscessus complex bacteria in vitro and may be considered for treatment of M. abscessus lung disease.
Speer, Alexander; Rowland, Jennifer L.; Haeili, Mehri; Niederweis, Michael
Copper resistance mechanisms are crucial for many pathogenic bacteria, including Mycobacterium tuberculosis, during infection because the innate immune system utilizes copper ions to kill bacterial intruders. Despite several studies detailing responses of mycobacteria to copper, the pathways by which copper ions cross the mycobacterial cell envelope are unknown. Deletion of porin genes in Mycobacterium smegmatis leads to a severe growth defect on trace copper medium but simultaneously increases tolerance for copper at elevated concentrations, indicating that porins mediate copper uptake across the outer membrane. Heterologous expression of the mycobacterial porin gene mspA reduced growth of M. tuberculosis in the presence of 2.5 μM copper by 40% and completely suppressed growth at 15 μM copper, while wild-type M. tuberculosis reached its normal cell density at that copper concentration. Moreover, the polyamine spermine, a known inhibitor of porin activity in Gram-negative bacteria, enhanced tolerance of M. tuberculosis for copper, suggesting that copper ions utilize endogenous outer membrane channel proteins of M. tuberculosis to gain access to interior cellular compartments. In summary, these findings highlight the outer membrane as the first barrier against copper ions and the role of porins in mediating copper uptake in M. smegmatis and M. tuberculosis. PMID:24013632
Speer, Alexander; Rowland, Jennifer L; Haeili, Mehri; Niederweis, Michael; Wolschendorf, Frank
Copper resistance mechanisms are crucial for many pathogenic bacteria, including Mycobacterium tuberculosis, during infection because the innate immune system utilizes copper ions to kill bacterial intruders. Despite several studies detailing responses of mycobacteria to copper, the pathways by which copper ions cross the mycobacterial cell envelope are unknown. Deletion of porin genes in Mycobacterium smegmatis leads to a severe growth defect on trace copper medium but simultaneously increases tolerance for copper at elevated concentrations, indicating that porins mediate copper uptake across the outer membrane. Heterologous expression of the mycobacterial porin gene mspA reduced growth of M. tuberculosis in the presence of 2.5 μM copper by 40% and completely suppressed growth at 15 μM copper, while wild-type M. tuberculosis reached its normal cell density at that copper concentration. Moreover, the polyamine spermine, a known inhibitor of porin activity in Gram-negative bacteria, enhanced tolerance of M. tuberculosis for copper, suggesting that copper ions utilize endogenous outer membrane channel proteins of M. tuberculosis to gain access to interior cellular compartments. In summary, these findings highlight the outer membrane as the first barrier against copper ions and the role of porins in mediating copper uptake in M. smegmatis and M. tuberculosis.
Sermet-Gaudelus, Isabelle; Le Bourgeois, Muriel; Pierre-Audigier, Catherine; Offredo, Catherine; Guillemot, Didier; Halley, Sophie; Akoua-Koffi, Chantal; Vincent, Véronique; Sivadon-Tardy, Valérie; Ferroni, Agnès; Berche, Patrick; Scheinmann, Pierre; Lenoir, Gérard
We prospectively studied 298 patients with cystic fibrosis (mean age 11.3 years; range 2 months to 32 years; sex ratio, 0.47) for nontuberculous mycobacteria in respiratory samples from January 1, 1996, to December 31, 1999. Mycobacterium abscessus was by far the most prevalent nontuberculous mycobacterium: 15 patients (6 male, 9 female; mean age 11.9 years; range 2.5–22 years) had at least one positive sample for this microorganism (versus 6 patients positive for M. avium complex), including 10 with >3 positive samples (versus 3 patients for M. avium complex). The M. abscessus isolates from 14 patients were typed by pulsed-field gel electrophoresis: each of the 14 patients harbored a unique strain, ruling out a common environmental reservoir or person-to-person transmission. Water samples collected in the cystic fibrosis center were negative for M. abscessus. This major mycobacterial pathogen in children and teenagers with cystic fibrosis does not appear to be acquired nosocomially. PMID:14720400
Balseiro, Ana; Rodríguez, Oscar; González-Quirós, Pablo; Merediz, Isabel; Sevilla, Iker A; Davé, Dipesh; Dalley, Deanna J; Lesellier, Sandrine; Chambers, Mark A; Bezos, Javier; Muñoz, Marta; Delahay, Richard J; Gortázar, Christian; Prieto, José M
The prevalence, distribution and pathology related to infection with Mycobacterium bovis and other mycobacteria were determined in trapped (n=36) and road-killed (n=121) badgers in Spain from 2006 to 2010. The prevalence of M. bovis based on bacteriological culture from road-killed badgers was 8/121 (6.6%) and from trapped badgers was 0/36 (0%). Tuberculosis/M. bovis infection was evident in 15/121 (12.4%) road-killed badgers when bacteriology and histopathology were combined. Mycobacterium avium complex was isolated by culture from the tracheal aspirate of 1/36 (2.8%) trapped badgers and from tissue pools from 8/121 (6.6%) road-killed badgers.
Sohn, Sungmin; Wang, Sungho; Shi, Hyejin; Park, Sungrock; Lee, Sangki; Park, Kyoung Taek
A mixed infection of Mycobacterium abscessus subsp. abscessus (Mab) and Mycobacterium tuberculosis (MTB) in the lung is an unusual clinical manifestation and has not yet been reported. A 61-year-old woman had been treated for Mab lung disease and concomitant pneumonia, and was diagnosed with pulmonary tuberculosis (PTB). Despite both anti-PTB and anti-Mab therapy, her entire left lung was destroyed and collapsed. She underwent left pneumonectomy and received medical therapy. We were able to successfully treat her mixed infection by pneumonectomy followed by inhaled amikacin therapy. To the best of our knowledge, thus far, this is the first description of a mixed Mab and MTB lung infection. PMID:28180105
Abdel-Rahman, Zaid; Sengupta, Ruchira; Johnson, Laura
Mycobacterium celatum is a nontuberculous mycobacterium shown to cause symptoms similar to pulmonary M. tuberculosis. Certain strains have been shown to cross-react with the probes used to detect M. tuberculosis, making this a diagnostic challenge. We present a 56-year-old gentleman who developed signs and symptoms of lung infection with computed tomography scan of the chest showing right lung apex cavitation. Serial sputum samples were positive for acid-fast bacilli and nucleic acid amplification testing identified M. tuberculosis ribosomal RNA, resulting in treatment initiation. Further testing with high performance liquid chromatography showed a pattern consistent with M. celatum. This case illustrates the potential for M. celatum to mimic M. tuberculosis in both its clinical history and laboratory testing due to the identical oligonucleotide sequence contained in both. An increasing number of case reports suggest that early reliable differentiation could reduce unnecessary treatment and public health intervention associated with misdiagnosed tuberculosis. PMID:27895946
Valdés Hernández, Iliana; Montoro Cardoso, C Ernesto; Hernández-Pando, Rogelio
development of new antituberculosis vaccines requires the characterization of the cell-mediated immune responses induced by mycobacterial antigens. to determine the immunogenic potential of 'Mycobacterium habana' TMC-5135 when using subcutaneous vaccine in Balb/c mice. in this study, Balb/c mice were inoculated subcutaneously with live 'Mycobacterium habana' TMC-5135. The production of IFN gamma in cell suspensions obtained from the lungs, the spleen and the lymph nodes after stimulation with mycobacterial antigens Ag85b or culture filtrate antigens (CFA) was recorded. the production of IFN gamma after stimulation with CFA and Ag85b was higher in mice vaccinated with 'M. habana' than in animals immunized with BCG. these results encourage new research on 'M. habana' as vaccinal candidate against tuberculosis.
Merkal, R S; Crawford, J A; Whipple, D L
Wieners and sausages were prepared which contained the most heat-tolerant representative of the Mycobacterium avium-Mycobacterium intracellulare complex we were able to obtain. They also were prepared with infected tissues obtained from tuberculous swine. Processing conditions were as varied as possible. Neither incorporation of sodium nitrite in the emulsion nor presence of smoke during processing altered the heat susceptibility of the organisms. Substantial killing of the organisms occurred as wieners reached the upper processing temperatures, but hot oil or radiant heating of the "precooked" sausages allowed very short times within the killing range; hence, higher peak internal temperatures were necessary. The lethalities for these organisms of reaching and maintaining various processing temperatures are given. PMID:575610
Gross, W M; Hawkins, J E
In the context of a busy reference laboratory, radiometric selective inhibition tests were evaluated for rapid differentiation of Mycobacterium tuberculosis and Mycobacterium bovis and of the M. tuberculosis complex from other mycobacteria. p-Nitro-alpha-acetylamino-beta-hydroxypropiophenone at 5 micrograms and hydroxylamine hydrochloride at 62.5 and 125 micrograms per ml of 7H12 medium were used to separate the M. tuberculosis complex from other mycobacteria (MOTT bacilli). Since it is important epidemiologically to distinguish M. tuberculosis from M. bovis, susceptibility to 1 microgram of thiophene-2-carboxylic acid per ml was also determined radiometrically. By using these three agents as selective inhibitors, M. tuberculosis, M. bovis, and MOTT bacilli were differentiated with a high degree of specificity by a BACTEC radiometric procedure. Results of tests performed on clinical isolates submitted on solid medium to our reference laboratory were available within 5 days. PMID:3921561
Spositto, F L E; Campanerut, P A Z; Ghiraldi, L D; Leite, C Q F; Hirata, M H; Hirata, R D C; Siqueira, V L D; Cardoso, R Fressatti
We evaluated a multiplex-PCR to differentiate Mycobacterium bovis from M. tuberculosis Complex (MTC) by one step amplification based on simultaneous detection of pncA 169 C > G change in M. bovis and the IS6110 present in MTC species. Our findings showed the proposed multiplex-PCR is a very useful tool for complementation in differentiating M. bovis from other cultured MTC species.
Brown-Elliott, Barbara A.; Wallace, Richard J.; Petti, Cathy A.; Mann, Linda Bridge; McGlasson, Maria; Chihara, Shingo; Smith, Geremy L.; Painter, Patrick; Hail, Daymon; Wilson, Rebecca; Simmon, Keith E.
Reference isolates of Mycobacterium neoaurum, Mycobacterium aurum, and the nonvalidated species “Mycobacterium lacticola” were the focus of two recent molecular taxonomic studies. On the basis of this grouping, we identified 46 clinical pigmented, rapidly growing mycobacterial isolates. By 16S rRNA gene sequencing, only two major taxa were identified: M. neoaurum and a previously uncharacterized “M. neoaurum-like” group. The M. neoaurum-like group exhibited only 99.7% identity to M. neoaurum by 16S rRNA gene sequencing and 96.5% identity to M. neoaurum by rpoB sequencing and was named M. bacteremicum. No clinical isolates of M. aurum or M. lacticola were identified. Of isolates with known sources, 4/8 (50%) of M. bacteremicum isolates and 22/34 (65%) of M. neoaurum isolates were recovered from blood, and 35% of these were known to be from patients with catheter-related sepsis. MIC and clinical data on these 46 isolates of M. neoaurum and M. bacteremicum along with a review of 16 previously reported cases of infection with the M. neoaurum-M. lacticola group demonstrated that the isolates were highly susceptible to all drugs tested except clarithromycin, and most clinical cases were successfully treated. The clarithromycin resistance suggested the presence of an inducible erm gene reported in other species of rapidly growing mycobacteria. Sequencing studies are currently required to identify these two species. Strain ATCC 25791 (originally submitted as an example of Mycobacterium aurum) is proposed to be the type strain of M. bacteremicum. PMID:20881180
Pei, Zhiheng; Pride, David T.; Collins, Robert D.; Cover, Timothy L.; Blaser, Martin J.
We performed polymerase chain reaction analysis, for Mycobacterium species 16S rRNA, rpoB, and IS6110 sequences, on 25 tissue specimens from patients with sarcoidosis and on 25 control tissue specimens consisting of mediastinal or cervical lymph nodes and lung biopsies. Mycobacterium species 16S rRNA sequences were amplified from 12 (48%) rpoB sequences from 6 (24%) of the sarcoidosis specimens. In total, 16S rRNA or rpoB sequences were amplified from 15 sarcoidosis specimens (60%) but were not detected in any of the control tissues (p=0.00002, Chi square). In three specimens, the sequences resembled Mycobacterium species other than M. tuberculosis. All specimens with sequences consistent with M. tuberculosis were negative for IS6110. We provide evidence that one of a variety of Mycobacterium species, especially organisms resembling M. tuberculosis, is found in most patients with sarcoidosis. PMID:12453366
Mac Aogáin, Micheál; Roycroft, Emma; Raftery, Philomena; Mok, Simone; Fitzgibbon, Margaret; Rogers, Thomas R
Mycobacterium chimaera is an opportunistic human pathogen implicated in both pulmonary and cardiovascular infections. Here, we report the draft genome sequences of three strains isolated from human respiratory specimens. Copyright © 2015 Mac Aogáin et al.
Background: The Mycobacterium avium Complex (MAC) includes the species M. avium (MA), M. intracellulare (MI), and possibly others. Organisms belonging to the MAC are phylogenetically closely related, opportunistic pathogens. The macrophage inducing gene (mig) is the only well-des...
Background: The Mycobacterium avium Complex (MAC) includes the species M. avium (MA), M. intracellulare (MI), and possibly others. Organisms belonging to the MAC are phylogenetically closely related, opportunistic pathogens. The macrophage inducing gene (mig) is the only well-des...
Roycroft, Emma; Raftery, Philomena; Mok, Simone; Fitzgibbon, Margaret; Rogers, Thomas R.
Mycobacterium chimaera is an opportunistic human pathogen implicated in both pulmonary and cardiovascular infections. Here, we report the draft genome sequences of three strains isolated from human respiratory specimens. PMID:26634757
Badr, Hesham M.
The effectiveness of gamma irradiation on the inactivation of Mycobacterium paratuberculosis, Mycobacterium bovis and Mycobacterium tuberculosis in fresh soft cheese that prepared from artificially inoculated milk samples was studied. Irradiation at dose of 2 kGy was sufficient for the complete inactivation of these mycobacteria as they were not detected in the treated samples during storage at 4±1 °C for 15 days. Moreover, irradiation of cheese samples, that were prepared from un-inoculated milk, at this effective dose had no significant effects on their gross composition and contents from riboflavin, niacin and pantothenic acid, while significant decreases in vitamin A and thiamin were observed. In addition, irradiation of cheese samples had no significant effects on their pH and nitrogen fractions contents, except for the contents of ammonia, which showed a slight, but significant, increases due to irradiation. The analysis of cheese fats indicated that irradiation treatment induced significant increase in their oxidation parameters and contents from free fatty acids; however, the observed increases were relatively low. On the other hand, irradiation of cheese samples induced no significant alterations on their sensory properties. Thus, irradiation dose of 2 kGy can be effectively applied to ensure the safety of soft cheese with regards to these harmful mycobacteria.
Michel, Anita L
Mycobacterium fortuitum and at least 1 unidentified species of soil mycobacteria were isolated from lymph nodes from 4 of 5 African buffalo (Syncerus caffer) that had been culled because of positive test results using the Bovigam assay. The buffalo were part of a group of 16 free-ranging buffalo captured in the far north of the Kruger National Park (South Africa) assumed to be free of bovine tuberculosis. No Mycobacterium bovis was isolated. To investigate the possible cause of the apparent false-positive diagnosis, the Mycobacterium isolates were inoculated into 4 experimental cattle and their immune responses monitored over a 13-week period, using the gamma interferon assay. The immune reactivity was predominantly directed toward avian tuberculin purified protein derivative (PPD) and lasted for approximately 8 weeks. During that period 3 of 4 cattle yielded positive test results on 1 or 2 occasions. The immune responsiveness was boosted when the inoculations were repeated after 15 weeks, which led to 2 subsequent positive reactions in the experimental animal that did not react previously. Including an additional stimulatory antigen, sensitin prepared from M. fortuitum in the gamma interferon assay, showed that it was able to elicit a detectable gamma interferon response in all 4 experimentally inoculated cattle when applied in parallel with bovine and avian tuberculin PPD for the stimulation of blood samples. The implications of occasional cross-reactive responses in natural cases of infection with environmental mycobacteria in the diagnosis of bovine tuberculosis in African buffalo and cattle in South Africa are discussed.
Pfaller, Stacy; Tokarev, Vasily; Kessler, Collin; McLimans, Christopher; Gomez-Alvarez, Vicente; Wright, Justin; King, Dawn; Lamendella, Regina
We report here the draft genome sequence of the type strain Mycobacterium chimaera Fl-0169, a member of the Mycobacterium avium complex (MAC). M. chimaera Fl-0169(T) was isolated from a patient in Italy and is highly similar to strains of M. chimaera isolated in Ireland, although Fl-0169(T) possesses unique virulence genes. Copyright © 2017 Pfaller et al.
Bhatt, Achal; Green, Renee; Coles, Roswell; Condon, Michael; Connell, Nancy D.
A mutant of Mycobacterium smegmatis unable to use the dipeptide carnosine (β-alanyl-l-histidine) as a sole carbon or nitrogen source was isolated. Carnosinase activity and the ability to grow on β-Ala and/or l-His were similar in the mutant and the wild type. However, the mutant showed significant impairment in the uptake of carnosine. This study is the first description of a peptide utilization mutant of a mycobacterium. PMID:9852030
Neugebauer, Maria Gertrudes Fernandes Pereira; Neugebauer, Samuel Antônio; Almeida Junior, Hiram Larangeira; Mota, Laís Marques
Skin infections by Mycobacterium marinum are quite rare in our environment and, therefore, little studied. The majority of the lesions appear three weeks after traumas in aquariums, beaches and fish tanks. Lymph node drainage and systematization of the disease are rare and most lesions disappear in about three years. This case aims to show the effectiveness of the treatment used (lymecycline 150 mg/orally/day). This medication may be a new therapeutic option for the treatment of Mycobacterium marinum.
Neugebauer, Maria Gertrudes Fernandes Pereira; Neugebauer, Samuel Antônio; Almeida Junior, Hiram Larangeira; Mota, Laís Marques
Skin infections by Mycobacterium marinum are quite rare in our environment and, therefore, little studied. The majority of the lesions appear three weeks after traumas in aquariums, beaches and fish tanks. Lymph node drainage and systematization of the disease are rare and most lesions disappear in about three years. This case aims to show the effectiveness of the treatment used (lymecycline 150 mg/orally/day). This medication may be a new therapeutic option for the treatment of Mycobacterium marinum. PMID:25672310
Smith, Blaine D; Liras, Ioannis N; De Cicco, Ignacio A; Aisenberg, Gabriel Marcelo
Mycobacterium fortuitum is a non-tuberculous mycobacterium found in the soil and water of most regions of the world, and it can cause disease in immunocompetent and immunocompromised hosts. We present a 52-year-old man who developed a scalp abscess under a free flap for cranium coverage after a motor vehicle accident. Culture of material drained from the abscess grew M. fortuitum.
Mycobacterium arupense, Mycobacterium heraklionense, and a Newly Proposed Species, “Mycobacterium virginiense” sp. nov., but Not Mycobacterium nonchromogenicum, as Species of the Mycobacterium terrae Complex Causing Tenosynovitis and Osteomyelitis
Vasireddy, Sruthi; Brown-Elliott, Barbara A.; Wengenack, Nancy L.; Eke, Uzoamaka A.; Benwill, Jeana L.; Turenne, Christine; Wallace, Richard J.
Mycobacterium terrae complex has been recognized as a cause of tenosynovitis, with M. terrae and Mycobacterium nonchromogenicum reported as the primary etiologic pathogens. The molecular taxonomy of the M. terrae complex causing tenosynovitis has not been established despite approximately 50 previously reported cases. We evaluated 26 isolates of the M. terrae complex associated with tenosynovitis or osteomyelitis recovered between 1984 and 2014 from 13 states, including 5 isolates reported in 1991 as M. nonchromogenicum by nonmolecular methods. The isolates belonged to three validated species, one new proposed species, and two novel related strains. The majority of isolates (20/26, or 77%) belonged to two recently described species: Mycobacterium arupense (10 isolates, or 38%) and Mycobacterium heraklionense (10 isolates, or 38%). Three isolates (12%) had 100% sequence identity to each other by 16S rRNA and 99.3 to 100% identity by rpoB gene region V sequencing and represent a previously undescribed species within the M. terrae complex. There were no isolates of M. terrae or M. nonchromogenicum, including among the five isolates reported in 1991. The 26 isolates were susceptible to clarithromycin (100%), rifabutin (100%), ethambutol (92%), and sulfamethoxazole or trimethoprim-sulfamethoxazole (70%). The current study suggests that M. arupense, M. heraklionense, and a newly proposed species (“M. virginiense” sp. nov.; proposed type strain MO-233 [DSM 100883, CIP 110918]) within the M. terrae complex are the major causes of tenosynovitis and osteomyelitis in the United States, with little change over 20 years. Species identification within this complex requires sequencing methods. PMID:26962085
Singh, Pushpendra; Cole, Stewart T
Leprosy, which has afflicted human populations for millenia, results from infection with Mycobacterium leprae, an unculturable pathogen with an exceptionally long generation time. Considerable insight into the biology and drug resistance of the leprosy bacillus has been obtained from genomics. M. leprae has undergone reductive evolution and pseudogenes now occupy half of its genome. Comparative genomics of four different strains revealed remarkable conservation of the genome (99.995% identity) yet uncovered 215 polymorphic sites, mainly single nucleotide polymorphisms, and a handful of new pseudogenes. Mapping these polymorphisms in a large panel of strains defined 16 single nucleotide polymorphism-subtypes that showed strong geographical associations and helped retrace the evolution of M. leprae. PMID:21162636
Hui, Yee Man Tracy; Pillinger, Toby; Luqmani, Asad; Cooper, Nichola
Haemophagocytic lymphohistiocytosis (HLH) is a rare, potentially fatal condition that can be primary or secondary. Secondary HLH can occur in association with infections, most commonly viral infections, but has also been reported in association with Mycobacterium tuberculosis (TB). Prompt identification of the underlying cause of HLH is important as it guides treatment decisions. Early initiation of appropriate treatment (eg, anti-TB treatment) reduces morbidity and mortality. We present a case of HLH associated with TB infection. Initial TB investigations were negative and standard combination chemoimmunotherapy for HLH resulted in a limited clinical response. On apparent relapse of HLH, further investigation revealed TB with changes on CT chest, granuloma on bone marrow and eventual positive TB culture on bronchoalveolar lavage. Subsequent treatment with quadruple anti-TB treatment resulted in rapid clinical response and disease remission. We advocate continued monitoring for TB infection in patients with HLH, and prophylaxis or full treatment for those at high risk. PMID:25870214
Kertcher, J A; Chen, M F; Charache, P; Hwangbo, C C; Camargo, E E; McIntyre, P A; Wagner, H N
A 48-hour radiometric test for determining the drug susceptibility of Mycobacterium tuberculosis has been developed. The test is based on the measurement of 14CO2 produced by the oxidation of formate labeled with carbon-14. The test system uses 5 X 10(7) organisms in 1 ml of Middlebrook 7H9 medium plus albumin-dextrose-catalase enrichment and 1 muCi of [14C]formate. The 14CO2 produced is measured in an ionization chamber at 24-, 48-, and 72-hour intervals, with and without the addition of antituberculous drugs. Isoniazid, streptomycin, rifampin, and ethambutol were each tested at 3 concentrations by the radiometric method and the reference (agar dilution) method. Six standard strains and 21 patient isolates were compared by both methods. Production of 14CO2 was quantitatively decreased in the presence of drugs that inhibit the organism. The radiometric method requires 2 days; the agar dilution, 14 to 21 days.
Samanovic, Marie I.; Darwin, K. H.
Mycobacterium tuberculosis (M. tuberculosis) resides mainly inside macrophages, which produce nitric oxide (NO) to combat microbial infections. Earlier studies revealed that proteasome-associated genes are required for M. tuberculosis to resist NO via a previously uncharacterized mechanism. Twelve years later, we elucidated the link between proteasome function and NO resistance in M. tuberculosis in Molecular Cell, 57 (2015), pp. 984-994. In a proteasome degradation-defective mutant, Rv1205, a homologue of the plant enzyme LONELY GUY (LOG) that is involved in the synthesis of phytohormones called cytokinins, accumulates and as a consequence results in the overproduction of cytokinins. Cytokinins break down into aldehydes that kill mycobacteria in the presence of NO. Importantly, this new discovery reveals for the first time that a mammalian bacterial pathogen produces cytokinins and leaves us with the question: why is M. tuberculosis, an exclusively human pathogen, producing cytokinins? PMID:28357289
Scherr, Nicole; Jayachandran, Rajesh; Mueller, Philipp; Pieters, Jean
Tuberculosis, caused by Mycobacterium tuberculosis, has become an important health and economic burden, with more than four thousand people succumbing to the disease every day. Thus, there is an urgent need to understand the molecular basis of this pathogen's success in causing disease in humans, in order to develop new drugs superior to conventional drugs available at present. One reason why M. tuberculosis is such a dangerous microbe lies within its ability to survive within infected hosts, thereby efficiently circumventing host immune responses. Over the past few years, a number of mechanisms have been unravelled that are utilized by M. tuberculosis to survive within hosts and to avoid immune defence mechanisms. Several of these mechanisms have been described in this communication that may be useful for the development of novel compounds to treat tuberculosis.
Ruiz Del Olmo Izuzquiza, Ignacio; Monforte Cirac, María L; Bustillo Alonso, Matilde; Burgués Prades, Pedro; Guerrero Laleona, Carmelo
Lymphadenitis is the most common clinical feature in nontuberculous mycobacterium infection in immunocompetent children. We present two case reports of M. lentiflavum lymphadenitis diagnosed in a tertiary hospital in the last 10 years. Routine tests were performed after persistent adenopathy, and a sample for culture was obtained, being positive for this microorganism. Both patients received oral antibiotics during several weeks. Case 1 needed complete excision after five months of treatment, whilst Case 2 was cured by medical therapy. M. lentiflavum is considered, among the newly described nontuberculous mycobacterial species, an emergent pathogen in our environment. It has its own microbiological and clinical characteristics, different from the rest of nontuberculous mycobacteria. Case reports are limited in the literature since the infection was described for the first time in 1997.
van Helden, P D; Victor, T C; Warren, R M; van Helden, E G
Research into and identification of Mycobacterium tuberculosis can take on a number of facets, many of which involve the use of DNA at one stage or another. The quality and quantity of DNA required will depend on the end-use requirement. For example, good yields of pure, high-molecular-weight DNA uncontaminated by DNA from other sources (i.e., homogeneous) are optimal for the generation of cosmid libraries and sequencing (1), Southern hybridization (2-6), or microarray analysis (7) for genome studies, whereas relatively crude DNA (fragmented DNA or DNA from multiple sources [i.e., heterogeneous]) may be adequate for PCR-based diagnosis (8-12) or amplification of regions of the genome for other purposes, e.g., identification of mutations conferring drug resistance (13,14).
Torrey, Heather L.; Keren, Iris; Via, Laura E.; Lee, Jong Seok; Lewis, Kim
Mycobacterium tuberculosis forms drug-tolerant persister cells that are the probable cause of its recalcitrance to antibiotic therapy. While genetically identical to the rest of the population, persisters are dormant, which protects them from killing by bactericidal antibiotics. The mechanism of persister formation in M. tuberculosis is not well understood. In this study, we selected for high persister (hip) mutants and characterized them by whole genome sequencing and transcriptome analysis. In parallel, we identified and characterized clinical isolates that naturally produce high levels of persisters. We compared the hip mutants obtained in vitro with clinical isolates to identify candidate persister genes. Genes involved in lipid biosynthesis, carbon metabolism, toxin-antitoxin systems, and transcriptional regulators were among those identified. We also found that clinical hip isolates exhibited greater ex vivo survival than the low persister isolates. Our data suggest that M. tuberculosis persister formation involves multiple pathways, and hip mutants may contribute to the recalcitrance of the infection. PMID:27176494
Parkash, O; Singh, B P
Although Mycobacterium leprae was the first bacterial pathogen identified causing human disease, it remains one of the few that is non-cultivable. Understanding the biology of M. leprae is one of the primary challenges in current leprosy research. Genomics has been extremely valuable, nonetheless, functional proteins are ultimately responsible for controlling most aspects of cellular functions, which in turn could facilitate parasitizing the host. Furthermore, bacterial proteins provide targets for most of the vaccines and immunodiagnostic tools. Better understanding of the proteomics of M. leprae could also help in developing new drugs against M. leprae. During the past nearly 15 years, there have been several developments towards the identification of M. leprae proteins employing contemporary proteomics tools. In this review, we discuss the knowledge gained on the biology and pathogenesis of M. leprae from current proteomic studies.
Bruning-Fann, C S; Schmitt, S M; Fitzgerald, S D; Payeur, J B; Whipple, D L; Cooley, T M; Carlson, T; Friedrich, P
During a survey for tuberculosis in wild carnivores and omnivores, Mycobacterium bovis was cultured from pooled lymph nodes of three adult female coyotes (Canis latrans) harvested by hunters in Michigan (USA). No gross or histologic lesions suggestive of tuberculosis were seen in these animals. One coyote was taken from Montmorency county and two coyotes from Alcona county located in the north-eastern portion of Michigan's Lower Peninsula where free-ranging white-tailed deer (Odocoileus virginianus) have been found infected with bovine tuberculosis. It is thought that these coyotes became infected with M. bovis through the consumption of tuberculous deer. Other species included in the survey were the opossum (Didelphis virginiana), raccoon (Procyon lotor), red fox (Vulpes vulpes), bobcat (Felis rufus), and badger (Taxidea taxus).
Malm, Sven; Linguissi, Laure S. Ghoma; Tekwu, Emmanuel M.; Vouvoungui, Jeannhey C.; Kohl, Thomas A.; Beckert, Patrick; Sidibe, Anissa; Rüsch-Gerdes, Sabine; Madzou-Laboum, Igor K.; Kwedi, Sylvie; Penlap Beng, Véronique; Frank, Matthias; Ntoumi, Francine
Tuberculosis is a leading cause of illness and death in Congo. No data are available about the population structure and transmission dynamics of the Mycobacterium tuberculosis complex strains prevalent in this central Africa country. On the basis of single-nucleotide polymorphisms detected by whole-genome sequencing, we phylogenetically characterized 74 MTBC isolates from Brazzaville, the capital of Congo. The diversity of the study population was high; most strains belonged to the Euro-American lineage, which split into Latin American Mediterranean, Uganda I, Uganda II, Haarlem, X type, and a new dominant sublineage named Congo type (n = 26). Thirty strains were grouped in 5 clusters (each within 12 single-nucleotide polymorphisms), from which 23 belonged to the Congo type. High cluster rates and low genomic diversity indicate recent emergence and transmission of the Congo type, a new Euro-American sublineage of MTBC. PMID:28221129
Harris, N. Beth; Barletta, Raúl G.
Mycobacterium avium subsp. paratuberculosis (basonym M. paratuberculosis) is the etiologic agent of a severe gastroenteritis in ruminants known as Johne's disease. Economic losses to the cattle industry in the United States are staggering, reaching $1.5 billion annually. A potential pathogenic role in humans in the etiology of Crohn's disease is under investigation. In this article, we review the epidemiology, pathogenesis, diagnostics, and disease control measures of this important veterinary pathogen. We emphasize molecular genetic aspects including the description of markers used for strain identification, diagnostics, and phylogenetic analysis. Recent important advances in the development of animal models and genetic systems to study M. paratuberculosis virulence determinants are also discussed. We conclude with proposals for the applications of these models and recombinant technology to the development of diagnostic, control, and therapeutic measures. PMID:11432810
Han, Xiang Y; Jessurun, Jose
Leprosy is caused by the well-known Mycobacterium leprae and the newly discovered M lepromatosis. Here, the authors describe 2 cases of leprosy with unusual clinical presentation caused by M lepromatosis. The patients, a 32-year-old man and a 50-year-old woman, both of Mexican origin, manifested high fever, lymphadenopathy and florid skin lesions in the form of erythema nodosum and Lucio's phenomenon as the first clinical presentation. Heavy infiltration of acid-fast bacilli was identified in the tissues that led to the diagnosis of lepromatous leprosy or diffuse leprosy. The patients were treated with multidrug regimen and responded appropriately. From the lymph node tissue, the authors showed the bacillus to be M lepromatosis, not M leprae as presumed previously, by differential polymerase chain reactions and analysis of gene sequences. These cases add to the growing studies on this organism, expand its endemic regions in Mexico and provide more clinical insight.
Zychowicz, Michael E
Mycobacterium tuberculosis has affected humans for much of our existence. The incidence of global tuberculosis infection continues to rise, especially in concert with HIV coinfection. Many disease processes, such as diabetes, increase the likelihood of tuberculosis infection. Tuberculosis bacteria can infect any bone, joint, tendon, or bursa; however, the most common musculoskeletal site for infection includes the spine and weight-bearing joints of the hip and knee. Many patients who present with osteoarticular tuberculosis infection will have a gradual onset of pain at the site of infection. Many patients who develop a musculoskeletal tuberculosis infection will have no evidence of a pulmonary tuberculosis infection on x-ray film and many will have very mild symptoms with the initial infection. Healthcare providers must remember that many patients who develop tuberculosis infection do not progress to active tuberculosis disease; however, the latent infection may become active with immune compromise.
Gill, Wendy P; Harik, Nada S; Whiddon, Molly R; Liao, Reiling P; Mittler, John E; Sherman, David R
Few tools exist to assess replication of chronic pathogens during infection. This has been a considerable barrier to understanding latent tuberculosis, and efforts to develop new therapies generally assume that the bacteria are very slowly replicating or nonreplicating during latency1–3. To monitor Mycobacterium tuberculosis replication within hosts, we exploit an unstable plasmid that is lost at a steady, quantifiable rate from dividing cells in the absence of antibiotic selection. By applying a mathematical model, we calculate bacterial growth and death rates during infection of mice. We show that during chronic infection the cumulative bacterial burden—enumerating total live, dead and removed organisms encountered by the mouse lung—is substantially higher than estimates from colony forming units. Our data show that M. tuberculosis replicates throughout the course of chronic infection of mice and is restrained by the host immune system. This approach may also shed light on the replication dynamics of other chronic pathogens. PMID:19182798
Hayashi, Daisuke; Takii, Takemasa; Mukai, Tetsu; Makino, Masahiko; Yasuda, Emi; Horita, Yasuhiro; Yamamoto, Ryuji; Fujiwara, Akiko; Kanai, Keita; Kondo, Maki; Kawarazaki, Aya; Yano, Ikuya; Yamamoto, Saburo; Onozaki, Kikuo
In order to evaluate the biochemical characteristics of 14 substrains of Mycobacterium bovis bacillus Calmette Guérin (BCG) - Russia, Moreau, Japan, Sweden, Birkhaug, Danish, Glaxo, Mexico, Tice, Connaught, Montreal, Phipps, Australia and Pasteur - we performed eight different biochemical tests, including those for nitrate reduction, catalase, niacin accumulation, urease, Tween 80 hydrolysis, pyrazinamidase, p-amino salicylate degradation and resistance to thiophene 2-carboxylic acid hydrazide. Catalase activities of the substrains were all low. Data for nitrate reduction, niacin accumulation, Tween 80 hydrolysis, susceptibility to hydrogen peroxide and nitrate, and optimal pH for growth were all variable among these substrains. These findings suggest that the heterogeneities of biochemical characteristics are relevant to the differences in resistance of BCG substrains to environmental stress. The study also contributes to the re-evaluation of BCG substrains for use as vaccines.
Oh, Chun-Taek; Moon, Cheol; Jeong, Myeong Seon; Kwon, Seung-Hae; Jang, Jichan
Mycobacterium abscessus is a human pathogen that is responsible for a broad spectrum of tissue infections and disseminated infections in immunodeficient patients. This pathogen is one of the most resistant organisms to chemotherapeutic agents. Therefore, we tested the hypothesis that the fruit fly, Drosophila melanogaster, is a genetically tractable model host for M. abscessus. In this context, we infected D. melanogaster with M. abscessus. This M. abscessus infection results in dissemination in the fly body, followed by death, which is accompanied by severe indirect flight muscle and brain damage. Our data show that M. abscessus can grow and replicate in D. melanogaster w(1118) and that it elicited a humoral immune response, especially of the Toll antimicrobial peptide pathway. To the best of our knowledge, this is the first report that mycobacteria induce the production of antimicrobial peptides in D. melanogaster.
Lee, Meng-Rui; Sheng, Wang-Huei; Hung, Chien-Ching; Yu, Chong-Jen; Lee, Li-Na; Hsueh, Po-Ren
Mycobacterium abscessus complex comprises a group of rapidly growing, multidrug-resistant, nontuberculous mycobacteria that are responsible for a wide spectrum of skin and soft tissue diseases, central nervous system infections, bacteremia, and ocular and other infections. M. abscessus complex is differentiated into 3 subspecies: M. abscessus subsp. abscessus, M. abscessus subsp. massiliense, and M. abscessus subsp. bolletii. The 2 major subspecies, M. abscessus subsp. abscessus and M. abscessus subsp. massiliense, have different erm(41) gene patterns. This gene provides intrinsic resistance to macrolides, so the different patterns lead to different treatment outcomes. M. abscessus complex outbreaks associated with cosmetic procedures and nosocomial transmissions are not uncommon. Clarithromycin, amikacin, and cefoxitin are the current antimicrobial drugs of choice for treatment. However, new treatment regimens are urgently needed, as are rapid and inexpensive identification methods and measures to contain nosocomial transmission and outbreaks.
Warner, Digby F; Koch, Anastasia; Mizrahi, Valerie
The increasing availability of whole-genome sequence (WGS) data for Mycobacterium tuberculosis, the bacterium that causes tuberculosis (TB), suggests that circulating genotypes have been molded by three dominant evolutionary forces: long-term persistence within the human population, which requires a core programme of infection, disease, and transmission; selective pressure on specific genomic loci, which provides evidence of lineage-specific adaptation to host populations; and drug exposure, which has driven the rapid emergence of resistant isolates following the global implementation of anti-TB chemotherapy. Here, we provide an overview of these factors in considering the implications of genotypic diversity for disease pathogenesis, vaccine efficacy, and drug treatment. Copyright © 2014 Elsevier Ltd. All rights reserved.
Forrellad, Marina A.; Klepp, Laura I.; Gioffré, Andrea; Sabio y García, Julia; Morbidoni, Hector R.; Santangelo, María de la Paz; Cataldi, Angel A.; Bigi, Fabiana
The Mycobacterium tuberculosis complex (MTBC) consists of closely related species that cause tuberculosis in both humans and animals. This illness, still today, remains to be one of the leading causes of morbidity and mortality throughout the world. The mycobacteria enter the host by air, and, once in the lungs, are phagocytated by macrophages. This may lead to the rapid elimination of the bacillus or to the triggering of an active tuberculosis infection. A large number of different virulence factors have evolved in MTBC members as a response to the host immune reaction. The aim of this review is to describe the bacterial genes/proteins that are essential for the virulence of MTBC species, and that have been demonstrated in an in vivo model of infection. Knowledge of MTBC virulence factors is essential for the development of new vaccines and drugs to help manage the disease toward an increasingly more tuberculosis-free world. PMID:23076359
Simner, Patricia J; Hyle, Emily P; Buckwalter, Seanne P; Branda, John A; Brown-Elliott, Barbara A; Franklin, Jameelah; Toney, Nadege C; de Man, Tom J B; Wallace, Richard J; Vasireddy, Ravikiran; Gandhi, Rajesh T; Wengenack, Nancy L
We present a case of tenosynovitis caused by a novel, slowly growing, nonchromogenic, nontuberculous mycobacterium (NTM). Originally misidentified as Mycobacterium tuberculosis complex, the NTM cross-reacts with the M. tuberculosis complex nucleic acid hybridization probe, a M. tuberculosis gamma interferon release assay, and is closely related to M. tuberculosis by 16S rRNA gene sequencing. Copyright © 2014, American Society for Microbiology. All Rights Reserved.
de Lalla, F; Maserati, R; Scarpellini, P; Marone, P; Nicolin, R; Caccamo, F; Rigoli, R
A combination of clarithromycin, ciprofloxacin, and amikacin for the treatment of Mycobacterium avium-Mycobacterium intracellulare bacteremia was evaluated in 12 AIDS patients. Mycobacteremia cleared in all patients by 2 to 8 weeks of treatment, and symptoms resolved. Four patients died; all had negative blood cultures until death, and disseminated M. avium-M. intracellulare complex infection was not considered the primary cause of death. PMID:1387303
Svetlíková, Zuzana; Škovierová, Henrieta; Niederweis, Michael; Gaillard, Jean-Louis; McDonnell, Gerald; Jackson, Mary
Nosocomial outbreaks attributable to glutaraldehyde-resistant, rapidly growing mycobacteria are increasing. Here, evidence is provided that defects in porin expression dramatically increase the resistance of Mycobacterium smegmatis and Mycobacterium chelonae to glutaraldehyde and another aldehyde disinfectant, ortho-phthalaldehyde. Since defects in porin activity also dramatically increased the resistance of M. chelonae to drugs, there is thus some concern that the widespread use of glutaraldehyde and ortho-phthalaldehyde in clinical settings may select for drug-resistant bacteria. PMID:19581465
Wang, Shu-Xiang; Yang, Chang-Jen; Chen, Yu-Chuan; Lay, Chorng-Jang; Tsai, Chen-Chi
Nontuberculous mycobacterium (NTM) is an infrequent cause of prosthetic knee joint infections. Simultaneous infection with different NTM species in a prosthetic knee joint has not been previously reported. A case of prosthetic knee joint infection caused by Mycobacterium abscessus and M. fortuitum is described in this report. The patient was successfully treated with adequate antibiotics and surgery. The clinical features of sixteen previously reported cases of prosthetic knee joint infection caused by NTM are reviewed.
Emori, Mikiko; Kajiki, Akira; Ikedo, Yukari; Ochiai, Sanae; Iwata, Yasuhiro; Harada, Yasuko; Kitahara, Yoshinari
We described clinical features of pulmonary Mycobacterium scofulaceum disease. We described 15 cases of pulmonary Mycobacterium scrofulaceum infection admitted to National Hospital Organization Omuta National Hospital from 1989 to 2003 and reviewed the clinical feature, the findings of chest radiograph, and clinical course. Sex ratio was 8 male cases and 7 female cases, and the average age was 65.9 years old. Smoking history was found in 8 patients and occupational history of the dust inhalation was found in 7 patients with pulmonary M. scrofulaceum infection. There were 11 cases of tuberculosis-like form and 4 cases of nodular-bronchiectasis form according to the NTM Research society classification based on the findings of chest radiography. Improvement of the findings of chest radiography was seen in 4 patients by therapy, while no change or aggravation in 11 patients. Five patients died and among them, 3 died due to aggravation of pulmonary M. scrofulaceum infection. Cases showing tuberculosis-like form were dominant, and most of them showed extensive lesions when they were diagnosed, and these facts were considered to be major factors of difficulty in the treatment of this infection. The facts that 7 cases had occupational exposure to the dust, obstructive pulmonary disease in 3 cases, and 6 cases showed sputum culture positive for other nontuberculous mycobacteriosis, suggest that local resistance of lung might be attenuated, and this could be one of factors of onset and development of this infection. Only 4 cases showed improvement, while 5 cases died (primary disease death in 3 cases) and it was thought that the prognosis of the disease was in general poor.
Asante-Poku, Adwoa; Otchere, Isaac Darko; Osei-Wusu, Stephen; Sarpong, Esther; Baddoo, Akosua; Forson, Audrey; Laryea, Clement; Borrell, Sonia; Bonsu, Frank; Hattendorf, Jan; Ahorlu, Collins; Koram, Kwadwo A; Gagneux, Sebastien; Yeboah-Manu, Dorothy
Mycobacterium africanum comprises two phylogenetic lineages within the M. tuberculosis complex (MTBC) and is an important cause of human tuberculosis (TB) in West Africa. The reasons for this geographic restriction of M. africanum remain unclear. Here, we performed a prospective study to explore associations between the characteristics of TB patients and the MTBC lineages circulating in Ghana. We genotyped 1,211 MTBC isolates recovered from pulmonary TB patients recruited between 2012 and 2014 using single nucleotide polymorphism typing and spoligotyping. Associations between patient and pathogen variables were assessed using univariate and multivariate logistic regression. Of the 1,211 MTBC isolates analysed, 71.9 % (871) belonged to Lineage 4; 12.6 % (152) to Lineage 5 (also known as M. africanum West-Africa 1), 9.2 % (112) to Lineage 6 (also known as M. africanum West-Africa 2) and 0.6 % (7) to Mycobacterium bovis. Univariate analysis revealed that Lineage 6 strains were less likely to be isoniazid resistant compared to other strains (odds ratio = 0.25, 95 % confidence interval (CI): 0.05-0.77, P < 0.01). Multivariate analysis showed that Lineage 5 was significantly more common in patients from the Ewe ethnic group (adjusted odds ratio (adjOR): 2.79; 95 % CI: 1.47-5.29, P < 0.001) and Lineage 6 more likely to be found among HIV-co-infected TB patients (adjOR = 2.2; 95 % confidence interval (CI: 1.32-3.7, P < 0.001). Our findings confirm the importance of M. africanum in Ghana and highlight the need to differentiate between Lineage 5 and Lineage 6, as these lineages differ in associated patient variables.
Rombouts, Yoann; Alibaud, Laeticia; Carrère-Kremer, Séverine; Maes, Emmanuel; Tokarski, Caroline; Elass, Elisabeth; Kremer, Laurent; Guérardel, Yann
We have recently established the fine structure of the glycan backbone of lipooligosaccharides (LOS-I to LOS-IV) isolated from Mycobacterium marinum, a close relative of Mycobacterium tuberculosis. These studies culminated with the description of an unusual terminal N-acylated monosaccharide that confers important biological functions to LOS-IV, such as macrophage activation, that may be relevant to granuloma formation. It was, however, also suggested that the lipid moiety was required for LOSs to exert their immunomodulatory activity. Herein, using highly purified LOSs from M. marinum, we have determined through a combination of mass spectrometric and NMR techniques, the structure and localization of the fatty acids composing the lipid moiety. The occurrence of two distinct polymethyl-branched fatty acids presenting specific localizations is consistent with the presence of two highly related polyketide synthases (Pks5 and Pks5.1) in M. marinum and presumably involved in the synthesis of these fatty acyl chains. In addition, a bioinformatic search permitted us to identify a set of enzymes potentially involved in the biosynthesis or transfer of these lipids to the LOS trehalose unit. These include MMAR_2343, a member of the Pap (polyketide-associated protein) family, that acylates trehalose-based glycolipids in M. marinum. The participation of MMAR_2343 to LOS assembly was demonstrated using a M. marinum mutant carrying a transposon insertion in the MMAR_2343 gene. Disruption of MMAR_2343 resulted in a severe LOS breakdown, indicating that MMAR_2343, hereafter designated PapA4, fulfills the requirements for LOS acylation and assembly. PMID:21803773
Kim, Byoung-Jun; Math, Renukaradhya K; Jeon, Che Ok; Yu, Hee-Kyung; Park, Young-Gil; Kook, Yoon-Hoh; Kim, Bum-Joon
A slow-growing non-chromogenic mycobacterium was isolated from a patient with pulmonary disease. Phenotypically, strain 05-1390(T) was similar to Mycobacterium intracellulare ATCC 13950(T). The 16S rRNA gene sequence (1385 bp) of strain 05-1390(T) showed a high degree of similarity to those of the M. intracellulare complex, namely Mycobacterium marseillense 5351974(T) (100 %), M. intracellulare ATCC 13950(T) (99.8 %) and Mycobacterium chimaera DSM 44623(T) (99.9 %). Phylogenetic analysis based on internal transcribed spacer 1 (ITS1) and the hsp65 gene indicated that strain 05-1390(T) was closely related to M. intracellulare ATCC 13950(T), but that it was a distinct phylogenetic entity. Of particular interest, an analysis based on the rpoB gene (701 bp) showed that it is closely related to Mycobacterium parascrofulaceum ATCC BAA-614(T) (99.4 %), a scotochromogenic strain, rather than to the M. intracellulare-related strains. Unique MALDI-TOF MS profiles also supported the taxonomic status of this strain as a distinct species. These data support the conclusion that strain 05-1390(T) represents a novel mycobacterial species, for which the name Mycobacterium yongonense sp. nov. is proposed; the type strain is 05-1390(T) ( = DSM 45126(T) = KCTC 19555(T)).
Lebrun, Léa; Weill, François-Xavier; Lafendi, Leila; Houriez, Florence; Casanova, François; Gutierrez, M Cristina; Ingrand, Didier; Lagrange, Philippe; Vincent, Véronique; Herrmann, Jean Louis
Using INNO-LiPA-MYCOBACTERIA (Lipav1; Innogenetics) and the AccuProbe (Gen-Probe Inc./bioMérieux) techniques, 35 Mycobacterium avium-Mycobacterium intracellulare-Mycobacterium scrofulaceum (MAC/MAIS) complex strains were identified between January 2000 and December 2002. Thirty-four of 35 isolates were positive only for the MAIS complex probe by Lipav1 and were further analyzed by INNO-LiPA-MYCOBACTERIA version 2 (Lipav2), hsp65 PCR restriction pattern analysis (PRA), and ribosomal internal transcribed spacer (ITS), hsp65, and 16S rRNA sequences. Lipav2 identified 14 of 34 strains at the species level, including 11 isolates positive for the newly specific MAC sequevar Mac-A probe (MIN-2 probe). Ten of these 11 isolates corresponded to sequevar Mac-A, which was recently defined as Mycobacterium chimerae sp. nov. Among the last 20 of the 34 MAIS isolates, 17 (by hsp65 PRA) and 18 (by hsp65 sequence) were characterized as M. avium. Ten of the 20 were identified as Mac-U sequevar. All these 20 isolates were identified as M. intracellulare by 16S rRNA sequence except one isolate identified as Mycobacterium paraffinicum by 16S rRNA and ITS sequencing. One isolate out of 35 isolates that was positive for M. avium by AccuProbe and that was Mycobacterium genus probe positive and MAIS probe negative by Lipav1 and Lipav2 might be considered a new species. In conclusion, the new INNO-LiPA-MYCOBACTERIA allowed the identification of 40% of the previously unidentified MAIS isolates at the species level. The results of the Lipav2 assay on the MAIS isolates confirm the great heterogeneity of this group and suggest the use of hsp65 or ITS sequencing for precise identification of such isolates.
Pathogenic mycobacteria of the Mycobacterium tuberculosis complex such as Mycobacterium bovis, induce a characteristic lesion known as a granulomas. Granulomas represent a specific host response to chronic antigenic stimuli, such as foreign bodies, certain bacterial components, or persistent pathoge...
Hernández, A; Martró, E; Matas, L; Ausina, V
Quantitative suspension and carrier tests were used to compare the activity of Perasafe and Cidex against Mycobacterium tuberculosis, Mycobacterium avium-intracellulare, Mycobacterium fortuitum, and Mycobacterium chelonae. The interference of an organic load, and of hard water was also considered. Both agents achieved reductions exceeding 10(5)-fold within 20 and 30 min for all the strains tested. Perasafe is thus mycobactericidal and a viable alternative to Cidex for intermediate or high-level disinfection.
Tortoli, E; Piersimoni, C; Bacosi, D; Bartoloni, A; Betti, F; Bono, L; Burrini, C; De Sio, G; Lacchini, C; Mantella, A
Mycobacterium celatum is a recently described species which, on the basis of conventional tests, may be misidentified as Mycobacterium xenopi or as belonging to the Mycobacterium avium complex. Only genomic sequencing or high-performance liquid chromatography of cell wall mycolic acids can presently allow a correct identification of this mycobacterium. Two cases of infection due to M. celatum, in AIDS patients, are described here. The quantitative susceptibility pattern of the isolates to a wide spectrum of drugs is also reported. PMID:7699029
Cheung, Pui-Yi; Kinkle, Brian K.
Degradative strains of fast-growing Mycobacterium spp. are commonly isolated from polycyclic aromatic hydrocarbon (PAH)-contaminated soils. Little is known, however, about the ecology and diversity of indigenous populations of these fast-growing mycobacteria in contaminated environments. In the present study 16S rRNA genes were PCR amplified using Mycobacterium-specific primers and separated by temperature gradient gel electrophoresis (TGGE), and prominent bands were sequenced to compare the indigenous Mycobacterium community structures in four pairs of soil samples taken from heavily contaminated and less contaminated areas at four different sites. Overall, TGGE profiles obtained from heavily contaminated soils were less diverse than those from less contaminated soils. This decrease in diversity may be due to toxicity, since significantly fewer Mycobacterium phylotypes were detected in soils determined to be toxic by the Microtox assay than in nontoxic soils. Sequencing and phylogenetic analysis of prominent TGGE bands indicated that novel strains dominated the soil Mycobacterium community. Mineralization studies using [14C]pyrene added to four petroleum-contaminated soils, with and without the addition of the known pyrene degrader Mycobacterium sp. strain RJGII-135, indicated that inoculation increased the level of degradation in three of the four soils. Mineralization results obtained from a sterilized soil inoculated with strain RJGII-135 suggested that competition with indigenous microorganisms may be a significant factor affecting biodegradation of PAHs. Pyrene-amended soils, with and without inoculation with strain RJGII-135, experienced both increases and decreases in the population sizes of the inoculated strain and indigenous Mycobacterium populations during incubation. PMID:11319104
van Ingen, Jakko; Lindeboom, Jerome A; Hartwig, Nico G; de Zwaan, Rina; Tortoli, Enrico; Dekhuijzen, P N Richard; Boeree, Martin J; van Soolingen, Dick
Slowly growing, scotochromogenic bacteria of a novel Mycobacterium species were isolated from lymph node samples in two children and pulmonary samples in two elderly patients from different regions in the Netherlands as well as from a surface water sample in Zambia. Its 16S rRNA gene, 16S-23S internal transcribed spacer (ITS), hsp65 and rpoB gene sequences are unique in comparison with other mycobacteria. Phylogenetic analysis based on the 16S rRNA gene sequence revealed that these micro-organisms are most closely related to Mycobacterium scrofulaceum ATCC 19981(T) (8 differences; 0.6 % divergence). The hsp65 sequence shows 96 % similarity to that of Mycobacterium saskatchewanense MB54784 and the rpoB sequence shows 95 % similarity to that of Mycobacterium chimaera CIP 107892(T). The 16S-23S ITS sequence places these micro-organisms within the Mycobacterium avium complex, as a novel ITS sequevar. This is not supported by analysis of the 16S rRNA, hsp65 or rpoB gene sequences. Their scotochromogenicity, combined with mostly positive urease, positive semiquantitative catalase and negative tellurite reduction tests, set these isolates apart from related species. The mycolic acid patterns, obtained by HPLC, are similar to that of Mycobacterium scrofulaceum, though the peak heights and distribution present minor differences. We propose the name Mycobacterium mantenii sp. nov. for this novel species. The type strain, isolated from a lymph node biopsy sample, is strain 04-1474(T) (=NLA000401474(T) =CIP 109863(T) =DSM 45255(T)).
Boyle, Daniel P; Zembower, Teresa R; Qi, Chao
We evaluated the ability of the Vitek MS system to classify clinical pulmonary Mycobacterium avium complex isolates compared to multilocus sequence analysis. Vitek MS accurately identified 55% of the isolates as M. avium and 18% as M. intracellulare, but misidentified 24 (27%) Mycobacterium chimaera isolates as Mycobacterium intracellulare.
Flint, Jessica L.; Kowalski, Joseph C.; Karnati, Pavan K.; Derbyshire, Keith M.
Conjugal DNA transfer occurs by an atypical mechanism in Mycobacterium smegmatis. The transfer system is chromosomally encoded and requires recipient recombination functions for both chromosome and plasmid transfer. Cis-acting sequences have been identified that confer mobility on nontransferable plasmids, but these are larger and have different properties to canonical oriT sites found in bacterial plasmids. To identify trans-acting factors required for mediating DNA transfer, a library of transposon insertion mutants was generated in the donor strain, and individual mutants were screened for their effect on transfer. From this screen, a collection of insertion mutants was isolated that increased conjugation frequencies relative to wild type. Remarkably, the mutations map to a 25-kb region of the M. smegmatis chromosome that is syntenous with the RD1 region of Mycobacterium tuberculosis, which is considered to be the primary attenuating deletion in the related vaccine strain Mycobacterium bovis bacillus Calmette–Guérin. The genes of the RD1 region encode a secretory apparatus responsible for exporting Cfp10- and Esat-6, both potent antigens and virulence factors. In crosses using two M. smegmatis donors, we show that wild-type cells can suppress the elevated transfer phenotype of mutant donors, which is consistent with the secretion of a factor that suppresses conjugation. Most importantly, the RD1 region of M. tuberculosis complements the conjugation phenotype of the RD1 mutants in M. smegmatis. Our results indicate that the M. tuberculosis and M. smegmatis RD1 regions are functionally equivalent and provide a unique perspective on the role of this critical secretion apparatus. PMID:15314236
Han, Xiang Y; Sizer, Kurt C; Thompson, Erika J; Kabanja, Juma; Li, Jun; Hu, Peter; Gómez-Valero, Laura; Silva, Francisco J
Mycobacterium lepromatosis is a newly discovered leprosy-causing organism. Preliminary phylogenetic analysis of its 16S rRNA gene and a few other gene segments revealed significant divergence from Mycobacterium leprae, a well-known cause of leprosy, that justifies the status of M. lepromatosis as a new species. In this study we analyzed the sequences of 20 genes and pseudogenes (22,814 nucleotides). Overall, the level of matching of these sequences with M. leprae sequences was 90.9%, which substantiated the species-level difference; the levels of matching for the 16S rRNA genes and 14 protein-encoding genes were 98.0% and 93.1%, respectively, but the level of matching for five pseudogenes was only 79.1%. Five conserved protein-encoding genes were selected to construct phylogenetic trees and to calculate the numbers of synonymous substitutions (dS values) and nonsynonymous substitutions (dN values) in the two species. Robust phylogenetic trees constructed using concatenated alignment of these genes placed M. lepromatosis and M. leprae in a tight cluster with long terminal branches, implying that the divergence occurred long ago. The dS and dN values were also much higher than those for other closest pairs of mycobacteria. The dS values were 14 to 28% of the dS values for M. leprae and Mycobacterium tuberculosis, a more divergent pair of species. These results thus indicate that M. lepromatosis and M. leprae diverged approximately 10 million years ago. The M. lepromatosis pseudogenes analyzed that were also pseudogenes in M. leprae showed nearly neutral evolution, and their relative ages were similar to those of M. leprae pseudogenes, suggesting that they were pseudogenes before divergence. Taken together, the results described above indicate that M. lepromatosis and M. leprae diverged from a common ancestor after the massive gene inactivation event described previously for M. leprae.
Baranyai, Zsuzsa; Krátký, Martin; Vinšová, Jarmila; Szabó, Nóra; Senoner, Zsuzsanna; Horváti, Kata; Stolaříková, Jiřina; Dávid, Sándor; Bősze, Szilvia
In the Mycobacterium genus over one hundred species are already described and new ones are periodically reported. Species that form colonies in a week are classified as rapid growers, those requiring longer periods (up to three months) are the mostly pathogenic slow growers. More recently, new emerging species have been identified to lengthen the list, all rapid growers. Of these, Mycobacterium abscessus is also an intracellular pathogen and it is the most chemotherapy-resistant rapid-growing mycobacterium. In addition, the cases of multidrug-resistant Mycobacterium tuberculosis infection are also increasing. Therefore there is an urgent need to find new active molecules against these threatening strains. Based on previous results, a series of salicylanilides, salicylanilide 5-chloropyrazinoates and carbamates was designed, synthesized and characterised. The compounds were evaluated for their in vitro activity on M. abscessus, susceptible M. tuberculosis H37Rv, multidrug-resistant (MDR) M. tuberculosis MDR A8, M. tuberculosis MDR 9449/2006 and on the extremely-resistant Praha 131 (XDR) strains. All derivatives exhibited a significant activity with minimum inhibitory concentrations (MICs) in the low micromolar range. Eight salicylanilide carbamates and two salicylanilide esters exhibited an excellent in vitro activity on M. abscessus with MICs from 0.2 to 2.1 μM, thus being more effective than ciprofloxacin and gentamicin. This finding is potentially promising, particularly, as M. abscessus is a threateningly chemotherapy-resistant species. M. tuberculosis H37Rv was inhibited with MICs from 0.2 μM, and eleven compounds have lower MICs than isoniazid. Salicylanilide esters and carbamates were found that they were effective also on MDR and XDR M. tuberculosis strains with MICs ≥1.0 μM. The in vitro cytotoxicity (IC50) was also determined on human MonoMac-6 cells, and selectivity index (SI) of the compounds was established. In general, salicylanilide
Validation of a Multiplex Real-Time PCR Assay for Detection of Mycobacterium spp., Mycobacterium tuberculosis Complex, and Mycobacterium avium Complex Directly from Clinical Samples by Use of the BD Max Open System.
Rocchetti, Talita T; Silbert, Suzane; Gostnell, Alicia; Kubasek, Carly; Widen, Raymond
A multiplex real-time PCR was validated on the BD Max open system to detect different Mycobacterium tuberculosis complex, Mycobacterium avium complex, and Mycobacterium spp. directly from clinical samples. The PCR results were compared to those with traditional cultures. The multiplex PCR assay was found to be a specific and sensitive method for the rapid detection of mycobacteria directly from clinical specimens. Copyright © 2016, American Society for Microbiology. All Rights Reserved.
Hussain, Afzal; Singh, Sandeep Kumar
Tuberculosis is the most widespread and deadly airborne disease caused by Mycobacterium tuberculosis. The two-pronged lethal effect on the bacteria using lipids/surfactants and anti-tubercular drugs may render the miniaturization of dose owing to synergistic and tandem effect of both. The current research has been focused on screening and evaluating various lipids/surfactants possessing inherent anti-mycobacterium activity that can ferry the anti-tubercular drugs. In vitro anti-mycobacterium activity was evaluated using agar well diffusion method. Furthermore, time-concentration dependent killing and DNA/RNA content release studies were performed to correlate the findings. The exact mechanism of bacterial killing was further elucidated by electron/atomic force microscopy studies. Finally, to negate any toxicity, in vitro hemolysis and toxicity studies were performed. The study revealed that capmul MCM C-8, labrasol and acconon C-80 possessed highest in vitro anti-mycobacterium activity. Electron/atomic force microscopy results confirmed in vitro studies and verified the killing of Mycobacterium owing to the release of cytoplasmic content after cell wall fragmentation and disruption. Moreover, the least hemolysis and hundred percent survivals rate of mice using the excipients demonstrated the safety aspects of explored excipients that can ferry the anti-tubercular drugs. The present study concluded the safe, efficient and synergistic activity of the explored excipients and anti-tubercular drugs in controlling the menace of tuberculosis.
Huet, D; Godbert, B; Hermann, J; Zordan, J-M; Chabot, F; Andréjak, C
Pulmonary infection due to Mycobacterium malmoense can be difficult to diagnose. These difficulties can be responsible for a delay in the implementation of optimal treatment. Moreover, the treatment is not standardized. We report the case of a 56-year-old patient who developed a Mycobacterium malmoense pulmonary infection whose diagnosis was delayed due to initial suspicion of pulmonary Mycobacterium tuberculosis infection. Once the diagnosis was confirmed, the patient was treated empirically with rifampicin, ethambutol, and clarithromycin for 12 months after culture conversion, giving a total of 15 months. The clinical and radiological outcomes were favorable. This clinical case highlights the difficulties of diagnosing pulmonary atypical mycobacterial infection according to the American Thoracic Society criteria, particularly Mycobacterium malmoense, a non-tuberculous mycobacterium (NTM) quite uncommon in France. Currently, there are new diagnostic techniques such as GenoType Mycobacteria Direct(®). The second issue is the poorly standardized treatment of this NTM and many others, that are based on the recommendations of the British Thoracic Society. A national register has been set up by the MycoMed network, based essentially on the work of microbiologists but this register is unfortunately not exhaustive. A more systematic reporting strategy could allow cohort studies and therefore provide us with data on the most efficient drugs in the treatment of the rarest NTM infections. Copyright © 2016 SPLF. Published by Elsevier Masson SAS. All rights reserved.
Wang, Joyce; Moolji, Jalal; Dufort, Alex; Staffa, Alfredo; Domenech, Pilar; Reed, Michael B.
ABSTRACT Mycobacterium avium subsp. paratuberculosis is a host-adapted pathogen that evolved from the environmental bacterium M. avium subsp. hominissuis through gene loss and gene acquisition. Growth of M. avium subsp. paratuberculosis in the laboratory is enhanced by supplementation of the media with the iron-binding siderophore mycobactin J. Here we examined the production of mycobactins by related organisms and searched for an alternative iron uptake system in M. avium subsp. paratuberculosis. Through thin-layer chromatography and radiolabeled iron-uptake studies, we showed that M. avium subsp. paratuberculosis is impaired for both mycobactin synthesis and iron acquisition. Consistent with these observations, we identified several mutations, including deletions, in M. avium subsp. paratuberculosis genes coding for mycobactin synthesis. Using a transposon-mediated mutagenesis screen conditional on growth without myobactin, we identified a potential mycobactin-independent iron uptake system on a M. avium subsp. paratuberculosis-specific genomic island, LSPP15. We obtained a transposon (Tn) mutant with a disruption in the LSPP15 gene MAP3776c for targeted study. The mutant manifests increased iron uptake as well as intracellular iron content, with genes downstream of the transposon insertion (MAP3775c to MAP3772c [MAP3775-2c]) upregulated as the result of a polar effect. As an independent confirmation, we observed the same iron uptake phenotypes by overexpressing MAP3775-2c in wild-type M. avium subsp. paratuberculosis. These data indicate that the horizontally acquired LSPP15 genes contribute to iron acquisition by M. avium subsp. paratuberculosis, potentially allowing the subsequent loss of siderophore production by this pathogen. IMPORTANCE Many microbes are able to scavenge iron from their surroundings by producing iron-chelating siderophores. One exception is Mycobacterium avium subsp. paratuberculosis, a fastidious, slow-growing animal pathogen whose growth
Minassian, Angela M; Satti, Iman; Poulton, Ian D; Meyer, Joel; Hill, Adrian V S; McShane, Helen
There is currently no safe human challenge model of Mycobacterium tuberculosis infection to enable proof-of-concept efficacy evaluation of candidate vaccines against tuberculosis. In vivo antimycobacterial immunity could be assessed using intradermal Mycobacterium bovis bacille Calmette-Guérin (BCG) vaccination as a surrogate for M. tuberculosis infection. Healthy BCG-naive and BCG-vaccinated volunteers were challenged with intradermal BCG. BCG load was quantified from skin biopsy specimens by polymerase chain reaction (PCR) and culture colony-forming units. Cellular infiltrate was isolated by suction blisters and examined by flow cytometry. Prechallenge immune readouts were correlated with BCG load after challenge. In BCG-naive volunteers, live BCG was detected at the challenge site for up to 4 weeks and peaked at 2 weeks. Infiltration of mainly CD15(+) neutrophils was observed in blister fluid. In previously BCG-vaccinated individuals, PCR analysis of skin biopsy specimens reflected a degree of mycobacterial immunity. There was no significant correlation between BCG load after challenge and mycobacterial-specific memory T cells measured before challenge by cultured enzyme-linked immunospot assay. This novel experimental human challenge model provides a platform for the identification of correlates of antimycobacterial immunity and will greatly facilitate the rational down-selection of candidate tuberculosis vaccines. Further evaluation of this model with BCG and new vaccine candidates is warranted.
Pranada, Arthur B; Witt, Ellen; Bienia, Michael; Kostrzewa, Markus; Timke, Markus
The increasing number of infections caused by nontuberculous mycobacteria (NTM) has prompted the need for rapid and precise identification methods of these pathogens. Several studies report the applicability of MALDI-TOF mass spectrometry (MS) for identification of NTM. However, some closely related species have very similar spectral mass fingerprints, and until recently, Mycobacterium chimaera and M. intracellulare could not be separated from each other by MALDI-TOF MS. The conventional identification methods used in routine diagnostics have similar limitations. Recently, the differentiation of these two species within the Mycobacterium avium complex has become increasingly important due to reports of M. chimaera infections related to open heart surgery in Europe and in the USA. In this report, a method for the distinct differentiation of M. chimaera and M. intracellulare using a more detailed analysis of MALDI-TOF mass spectra is presented. Species-specific peaks could be identified and it was possible to assign all isolates (100 %) from reference strain collections as well as clinical isolates to the correct species. We have developed a model for the accurate identification of M. chimaera and M. intracellulare by MALDI-TOF MS. This approach has the potential for routine use in microbiology laboratories, as the model itself can be easily implemented into the software of the currently available systems by MALDI-TOF MS manufacturers.
Titgemeyer, Fritz; Amon, Johannes; Parche, Stephan; Mahfoud, Maysa; Bail, Johannes; Schlicht, Maximilian; Rehm, Nadine; Hillmann, Dietmar; Stephan, Joachim; Walter, Britta; Burkovski, Andreas; Niederweis, Michael
We present a comprehensive analysis of carbohydrate uptake systems of the soil bacterium Mycobacterium smegmatis and the human pathogen Mycobacterium tuberculosis. Our results show that M. smegmatis has 28 putative carbohydrate transporters. The majority of sugar transport systems (19/28) in M. smegmatis belong to the ATP-binding cassette (ABC) transporter family. In contrast to previous reports, we identified genes encoding all components of the phosphotransferase system (PTS), including permeases for fructose, glucose, and dihydroxyacetone, in M. smegmatis. It is anticipated that the PTS of M. smegmatis plays an important role in the global control of carbon metabolism similar to those of other bacteria. M. smegmatis further possesses one putative glycerol facilitator of the major intrinsic protein family, four sugar permeases of the major facilitator superfamily, one of which was assigned as a glucose transporter, and one galactose permease of the sodium solute superfamily. Our predictions were validated by gene expression, growth, and sugar transport analyses. Strikingly, we detected only five sugar permeases in the slow-growing species M. tuberculosis, two of which occur in M. smegmatis. Genes for a PTS are missing in M. tuberculosis. Our analysis thus brings the diversity of carbohydrate uptake systems of fast- and a slow-growing mycobacteria to light, which reflects the lifestyles of M. smegmatis and M. tuberculosis in their natural habitats, the soil and the human body, respectively. PMID:17557815
Titgemeyer, Fritz; Amon, Johannes; Parche, Stephan; Mahfoud, Maysa; Bail, Johannes; Schlicht, Maximilian; Rehm, Nadine; Hillmann, Dietmar; Stephan, Joachim; Walter, Britta; Burkovski, Andreas; Niederweis, Michael
We present a comprehensive analysis of carbohydrate uptake systems of the soil bacterium Mycobacterium smegmatis and the human pathogen Mycobacterium tuberculosis. Our results show that M. smegmatis has 28 putative carbohydrate transporters. The majority of sugar transport systems (19/28) in M. smegmatis belong to the ATP-binding cassette (ABC) transporter family. In contrast to previous reports, we identified genes encoding all components of the phosphotransferase system (PTS), including permeases for fructose, glucose, and dihydroxyacetone, in M. smegmatis. It is anticipated that the PTS of M. smegmatis plays an important role in the global control of carbon metabolism similar to those of other bacteria. M. smegmatis further possesses one putative glycerol facilitator of the major intrinsic protein family, four sugar permeases of the major facilitator superfamily, one of which was assigned as a glucose transporter, and one galactose permease of the sodium solute superfamily. Our predictions were validated by gene expression, growth, and sugar transport analyses. Strikingly, we detected only five sugar permeases in the slow-growing species M. tuberculosis, two of which occur in M. smegmatis. Genes for a PTS are missing in M. tuberculosis. Our analysis thus brings the diversity of carbohydrate uptake systems of fast- and a slow-growing mycobacteria to light, which reflects the lifestyles of M. smegmatis and M. tuberculosis in their natural habitats, the soil and the human body, respectively.
Brugnera, Michelle Fernanda; Miyata, Marcelo; Zocolo, Guilherme Julião; Leite, Clarice Queico Fujimura; Zanoni, Maria Valnice Boldrin
Nontuberculous mycobacteria are resistant to conventional water treatment; indeed, they have been recovered from a wide variety of environmental sources. Here, we applied the photoelectrocatalytic technique using a Ti/TiO2-Ag photoanode to inactivate mycobacteria. For a mycobacteria population of 5 × 10(8) CFU mL(-1), we achieved 99.9 and 99.8% inactivation of Mycobacterium kansasii and Mycobacterium avium with rate constant of 6.2 × 10(-3) and 4.2 × 10(-3) min(-1), respectively, after 240 min. We compared the proposed method with the photolytic and photocatalytic methods. Using a mycobacteria population of 7.5 × 10(4) CFU mL(-1), the proposed Ti/TiO2-Ag photoanode elicited total mycobacteria inactivation within 3 min of treatment; the presence of Ag nanoparticles in the electrode provided 1.5 larger degradation rate constant as compared with the Ti/TiO2 anode (1.75 × 10(-2) for M. kansassi and 1.98 × 10(-2) for M. avium). We monitored the degradation of the metabolites released during cellular lysis by TOC removal, sugar release, chromatography, and mass spectrometry measurements; photoelectrocatalysis and Ti/TiO2-Ag photoanodes furnished the best results.
Youm, Jiwon; Saier, Milton H
The co-emergence of multidrug resistant pathogenic bacterial strains and the Human Immunodeficiency Virus pandemic has made tuberculosis a leading public health threat. The causative agent is Mycobacterium tuberculosis (Mtu), a facultative intracellular parasite. Mycobacterium leprae (Mle), a related organism that causes leprosy, is an obligate intracellular parasite. Given that different transporters are required for bacterial growth and persistence under a variety of growth conditions, we conducted comparative analyses of transport proteins encoded within the genomes of these two organisms. A minimal set of genes required for intracellular and extracellular life was identified. Drug efflux systems utilizing primary active transport mechanisms have been preferentially retained in Mle and still others preferentially lost. Transporters associated with environmental adaptation found in Mtu were mostly lost in Mle. These findings provide starting points for experimental studies that may elucidate the dependencies of pathogenesis on transport for these two pathogenic mycobacteria. They also lead to suggestions regarding transporters that function in intra- versus extra-cellular growth.
Herbst, Lawrence H.; Costa, Sylvia F.; Weiss, Louis M.; Johnson, Linda K.; Bartell, John; Davis, Raymond; Walsh, Michael; Levi, Michael
An outbreak of granulomatous dermatitis was investigated in a captive population of moray eels. The affected eels had florid skin nodules concentrated around the head and trunk. Histopathological examination revealed extensive granulomatous inflammation within the dermis and subcutaneous fascial plane between the fat and axial musculature. Acid-fast rods were detected within the smallest lesions, which were presumably the ones that had developed earliest. Eventually, after several months of incubation at room temperature, a very slowly growing acid-fast organism was isolated. Sequencing of the 16S rRNA gene identified it as a Mycobacterium species closely related (0.59% divergence) to M. triplex, an SAV mycobacterium. Intradermal inoculation of healthy green moray eels with this organism reliably reproduced the lesion. Experimentally induced granulomatous dermatitis appeared within 2 weeks of inoculation and slowly but progressively expanded during the 2 months of the experiment. Live organisms were recovered from these lesions at all time points, fulfilling Koch's postulates for this bacterium. In a retrospective study of tissues collected between 1993 and 1999 from five spontaneous disease cases, acid-fast rods were consistently found within lesions, and a nested PCR for the rRNA gene also demonstrated the presence of mycobacteria within affected tissues. PMID:11402008
Falkinham, Joseph O.; Norton, Cheryl D.; LeChevallier, Mark W.
Eight water distribution systems were sampled over an 18-month period (528 water and 55 biofilm samples) to measure the frequency of recovery and number of mycobacteria, particularly Mycobacterium avium and Mycobacterium intracellulare, in raw source waters before and after treatment and within the distribution system. The systems were chosen to assess the influence of source water, treatment, and assimilable organic carbon levels on mycobacterial numbers. Overall, mycobacterial recovery from the systems was low (15% of samples). Numbers of mycobacteria ranged from 10 to 700,000 CFU liter−1. The number of M. avium in raw waters was correlated with turbidity. Water treatment substantially reduced the number of mycobacteria in raw waters by 2 to 4 log units. Mycobacterial numbers were substantially higher in the distribution system samples (average, 25,000-fold) than in those collected immediately downstream from the treatment facilities, indicating that mycobacteria grow in the distribution system. The increase in mycobacterial numbers was correlated with assimilable organic carbon and biodegradable organic carbon levels (r2 = 0.65, P = 0.03). Although M. intracellulare was seldom recovered from water samples, it was frequently recovered (six of eight systems) in high numbers from biofilms (average, 600 CFU/cm2). Evidently, the ecological niches of M. avium and M. intracellulare are distinct. PMID:11229914
Mattow, J; Jungblut, P R; Schaible, U E; Mollenkopf, H J; Lamer, S; Zimny-Arndt, U; Hagens, K; Müller, E C; Kaufmann, S H
A proteome approach, combining high-resolution two-dimensional electrophoresis (2-DE) with mass spectrometry, was used to compare the cellular protein composition of two virulent strains of Mycobacterium tuberculosis with two attenuated strains of Mycobacterium bovis Bacillus Calmette-Guerin (BCG), in order to identify unique proteins of these strains. Emphasis was given to the identification of M. tuberculosis specific proteins, because we consider these proteins to represent putative virulence factors and interesting candidates for vaccination and diagnosis of tuberculosis. The genome of M. tuberculosis strain H37Rv comprises nearly 4000 predicted open reading frames. In contrast, the separation of proteins from whole mycobacterial cells by 2-DE resulted in silver-stained patterns comprising about 1800 distinct protein spots. Amongst these, 96 spots were exclusively detected either in the virulent (56 spots) or in the attenuated (40 spots) mycobacterial strains. Fifty-three of these spots were analyzed by mass spectrometry, of which 41 were identified, including 32 M. tuberculosis specific spots. Twelve M. tuberculosis specific spots were identified as proteins, encoded by genes previously reported to be deleted in M. bovis BCG. The remaining 20 spots unique for M. tuberculosis were identified as proteins encoded by genes that are not known to be missing in M. bovis BCG.
Youm, Jiwon; Saier, Milton H.
The co-emergence of multidrug resistant pathogenic bacterial strains and the HIV pandemic has made tuberculosis a leading public health threat. The causative agent is Mycobacterium tuberculosis (Mtu), a facultative intracellular parasite. Mycobacterium leprae (Mle), a related organism that causes leprosy, is an obligate intracellular parasite. Given that different transporters are required for bacterial growth and persistence under a variety of growth conditions, we conducted comparative analyses of transport proteins encoded within the genomes of these two organisms. A minimal set of genes required for intracellular and extracellular life were identified. Drug efflux systems utilizing primary active transport mechanisms have been preferentially retained in Mle and still others preferentially lost. Transporters associated with environmental adaptation found in Mtu were mostly lost in Mle. These findings provide starting points for experimental studies that may elucidate the dependencies of pathogenesis on transport for these two pathogenic mycobacteria. They also lead to suggestions regarding transporters that function in intra- versus extra-cellular growth. PMID:22179038
Tientcheu, Leopold D; Sutherland, Jayne S; de Jong, Bouke C; Kampmann, Beate; Jafali, James; Adetifa, Ifedayo M; Antonio, Martin; Dockrell, Hazel M; Ota, Martin O
In The Gambia, Mycobacterium tuberculosis (Mtb) and Mycobacterium africanum (Maf) are major causes of tuberculosis (TB). Maf is more likely to cause TB in immune suppressed individuals, implying differences in virulence. Despite this, few studies have assessed the underlying immunity to the two pathogens in human. In this study, we analyzed T-cell responses from 19 Maf- and 29 Mtb-infected HIV-negative patients before and after TB chemotherapy following overnight stimulation of whole blood with TB-specific antigens. Before treatment, percentages of early secreted antigenic target-6(ESAT-6)/culture filtrate protein-10(CFP-10) and purified protein derivative-specific single-TNF-α-producing CD4(+) and CD8(+) T cells were significantly higher while single-IL-2-producing T cells were significantly lower in Maf- compared with Mtb-infected patients. Purified protein derivative-specific polyfunctional CD4(+) T cells frequencies were significantly higher before than after treatment, but there was no difference between the groups at both time points. Furthermore, the proportion of CD3(+) CD11b(+) T cells was similar in both groups pretreatment, but was significantly lower with higher TNF-α, IL-2, and IFN-γ production in Mtb- compared with that of Maf-infected patients posttreatment. Our data provide evidence of differences in T-cell responses to two mycobacterial strains with differing virulence, providing some insight into TB pathogenesis with different Mtb strains that could be prospectively explored as biomarkers for TB protection or susceptibility.
Flores, Anthony R.; Parsons, Linda M.; Pavelka, Martin S.
Our laboratory previously constructed mutants of Mycobacterium tuberculosis and Mycobacterium smegmatis with deletions in the genes for their major β-lactamases, BlaC and BlaS, respectively, and showed that the mutants have increased susceptibilities to most β-lactam antibiotics, particularly the penicillins. However, there is still a basal level of resistance in the mutants to certain penicillins, and the susceptibilities of the mutants to some cephalosporin-based β-lactams are essentially the same as those of the wild types. We hypothesized that characterizing additional mutants (derived from β-lactamase deletion mutants) that are hypersusceptible to β-lactam antibiotics might reveal novel genes involved with other mechanisms of β-lactam resistance, peptidoglycan assembly, and cell envelope physiology. We report here the isolation and characterization of nine β-lactam antibiotic-hypersusceptible transposon mutants, two of which have insertions in genes known to be involved with peptidoglycan biosynthesis (ponA2 and dapB); the other seven mutants have insertions which affect novel genes. These genes can be classified into three groups: those involved with peptidoglycan biosynthesis, cell division, and other cell envelope processes. Two of the peptidoglycan-biosynthetic genes (ponA2 and pbpX) may encode β-lactam antibiotic-resistant enzymes proposed to be involved with the synthesis of the unusual diaminopimelyl linkages within the mycobacterial peptidoglycan. PMID:15743935
Chang, Jennifer C; Miner, Maurine D; Pandey, Amit K; Gill, Wendy P; Harik, Nada S; Sassetti, Christopher M; Sherman, David R
Recently, cholesterol was identified as a physiologically important nutrient for Mycobacterium tuberculosis survival in chronically infected mice. However, it remained unclear precisely when cholesterol is available to the bacterium and what additional bacterial functions are required for its metabolism. Here, we show that the igr locus, which we previously found to be essential for intracellular growth and virulence of M. tuberculosis, is required for cholesterol metabolism. While igr-deficient strains grow identically to the wild type in the presence of short- and long-chain fatty acids, the growth of these bacteria is completely inhibited in the presence of cholesterol. Interestingly, this mutant is still able to respire under cholesterol-dependent growth inhibition, suggesting that the bacteria can metabolize other carbon sources during cholesterol toxicity. Consistent with this hypothesis, we found that the growth-inhibitory effect of cholesterol in vitro depends on cholesterol import, as mutation of the mce4 sterol uptake system partially suppresses this effect. In addition, the Delta igr mutant growth defect during the early phase of disease is completely suppressed by mutating mce4, implicating cholesterol intoxication as the primary mechanism of attenuation. We conclude that M. tuberculosis metabolizes cholesterol throughout infection.
Miner, Maurine D; Chang, Jennifer C; Pandey, Amit K; Sassetti, Christopher M; Sherman, David R
Mycobacterium tuberculosis (MTB) acquisition and utilization of nutrients within the host cell is poorly understood, although it has been hypothesized that host lipids probably play an important role in MTB survival. Cholesterol has recently been identified as an important lipid for mycobacterial infection. The mce4 transport system is required for cholesterol import into bacterial cells, and deletion of mce4 locus resulted in severe attenuation in a chronic mouse model of infection. However, it has remained unclear what additional bacterial functions were required for utilization of this sterol. We have found that the igr locus, which was previously found essential for intracellular growth and virulence of MTB, is required for cholesterol metabolism: igr-deficient bacteria cannot grow using cholesterol as a primary carbon source. The growth-inhibitory effect of cholesterol in vitro depends on cholesterol import, as the delta igr mutant growth defect during the early phase of disease is completely suppressed by mutating mce4, implicating cholesterol intoxication as the primary mechanism of attenuation. We conclude that M. tuberculosis metabolizes cholesterol throughout the course of infection, and that degradation of this sterol is crucial for bacterial persistence.
Randall, Philippa J.; Hsu, Nai-Jen; Lang, Dirk; Cooper, Susan; Sebesho, Boipelo; Allie, Nasiema; Keeton, Roanne; Francisco, Ngiambudulu M.; Salie, Sumayah; Labuschagné, Antoinette; Quesniaux, Valerie; Ryffel, Bernhard; Kellaway, Lauriston
Mycobacterium tuberculosis infection of the central nervous system is thought to be initiated once the bacilli have breached the blood brain barrier and are phagocytosed, primarily by microglial cells. In this study, the interactions of M. tuberculosis with neurons in vitro and in vivo were investigated. The data obtained demonstrate that neurons can act as host cells for M. tuberculosis. M. tuberculosis bacilli were internalized by murine neuronal cultured cells in a time-dependent manner after exposure, with superior uptake by HT22 cells compared to Neuro-2a cells (17.7% versus 9.8%). Internalization of M. tuberculosis bacilli by human SK-N-SH cultured neurons suggested the clinical relevance of the findings. Moreover, primary murine hippocampus-derived neuronal cultures could similarly internalize M. tuberculosis. Internalized M. tuberculosis bacilli represented a productive infection with retention of bacterial viability and replicative potential, increasing 2- to 4-fold within 48 h. M. tuberculosis bacillus infection of neurons was confirmed in vivo in the brains of C57BL/6 mice after intracerebral challenge. This study, therefore, demonstrates neurons as potential new target cells for M. tuberculosis within the central nervous system. PMID:24566619
Randall, Philippa J; Hsu, Nai-Jen; Lang, Dirk; Cooper, Susan; Sebesho, Boipelo; Allie, Nasiema; Keeton, Roanne; Francisco, Ngiambudulu M; Salie, Sumayah; Labuschagné, Antoinette; Quesniaux, Valerie; Ryffel, Bernhard; Kellaway, Lauriston; Jacobs, Muazzam
Mycobacterium tuberculosis infection of the central nervous system is thought to be initiated once the bacilli have breached the blood brain barrier and are phagocytosed, primarily by microglial cells. In this study, the interactions of M. tuberculosis with neurons in vitro and in vivo were investigated. The data obtained demonstrate that neurons can act as host cells for M. tuberculosis. M. tuberculosis bacilli were internalized by murine neuronal cultured cells in a time-dependent manner after exposure, with superior uptake by HT22 cells compared to Neuro-2a cells (17.7% versus 9.8%). Internalization of M. tuberculosis bacilli by human SK-N-SH cultured neurons suggested the clinical relevance of the findings. Moreover, primary murine hippocampus-derived neuronal cultures could similarly internalize M. tuberculosis. Internalized M. tuberculosis bacilli represented a productive infection with retention of bacterial viability and replicative potential, increasing 2- to 4-fold within 48 h. M. tuberculosis bacillus infection of neurons was confirmed in vivo in the brains of C57BL/6 mice after intracerebral challenge. This study, therefore, demonstrates neurons as potential new target cells for M. tuberculosis within the central nervous system.
Lerner, Thomas R.; Repnik, Urska; Herbst, Susanne; Collinson, Lucy M.; Griffiths, Gareth
Mycobacterium tuberculosis modulation of macrophage cell death is a well-documented phenomenon, but its role during bacterial replication is less characterized. In this study, we investigate the impact of plasma membrane (PM) integrity on bacterial replication in different functional populations of human primary macrophages. We discovered that IFN-γ enhanced bacterial replication in macrophage colony-stimulating factor–differentiated macrophages more than in granulocyte–macrophage colony-stimulating factor–differentiated macrophages. We show that permissiveness in the different populations of macrophages to bacterial growth is the result of a differential ability to preserve PM integrity. By combining live-cell imaging, correlative light electron microscopy, and single-cell analysis, we found that after infection, a population of macrophages became necrotic, providing a niche for M. tuberculosis replication before escaping into the extracellular milieu. Thus, in addition to bacterial dissemination, necrotic cells provide first a niche for bacterial replication. Our results are relevant to understanding the environment of M. tuberculosis replication in the host. PMID:28242744
Domingo-Gonzalez, Racquel; Prince, Oliver; Cooper, Andrea; Khader, Shabaana A
Chemokines and cytokines are critical for initiating and coordinating the organized and sequential recruitment and activation of cells into Mycobacterium tuberculosis-infected lungs. Correct mononuclear cellular recruitment and localization are essential to ensure control of bacterial growth without the development of diffuse and damaging granulocytic inflammation. An important block to our understanding of TB pathogenesis lies in dissecting the critical aspects of the cytokine/chemokine interplay in light of the conditional role these molecules play throughout infection and disease development. Much of the data highlighted in this review appears at first glance to be contradictory, but it is the balance between the cytokines and chemokines that is critical, and the "goldilocks" (not too much and not too little) phenomenon is paramount in any discussion of the role of these molecules in TB. Determination of how the key chemokines/cytokines and their receptors are balanced and how the loss of that balance can promote disease is vital to understanding TB pathogenesis and to identifying novel therapies for effective eradication of this disease.
Mandal, Saurav; Roychowdhury, Tanmoy; Chirom, Keilash; Bhattacharya, Alok; Brojen Singh, R. K.
The mutifractal and long range correlation (C(r)) properties of strings, such as nucleotide sequence can be a useful parameter for identification of underlying patterns and variations. In this study C(r) and multifractal singularity function f(α) have been used to study variations in the genomes of a pathogenic bacteria Mycobacterium tuberculosis. Genomic sequences of M. tuberculosis isolates displayed significant variations in C(r) and f(α) reflecting inherent differences in sequences among isolates. M. tuberculosis isolates can be categorised into different subgroups based on sensitivity to drugs, these are DS (drug sensitive isolates), MDR (multi-drug resistant isolates) and XDR (extremely drug resistant isolates). C(r) follows significantly different scaling rules in different subgroups of isolates, but all the isolates follow one parameter scaling law. The richness in complexity of each subgroup can be quantified by the measures of multifractal parameters displaying a pattern in which XDR isolates have highest value and lowest for drug sensitive isolates. Therefore C(r) and multifractal functions can be useful parameters for analysis of genomic sequences.
Mandal, Saurav; Roychowdhury, Tanmoy; Chirom, Keilash; Bhattacharya, Alok; Brojen Singh, R. K.
The mutifractal and long range correlation (C(r)) properties of strings, such as nucleotide sequence can be a useful parameter for identification of underlying patterns and variations. In this study C(r) and multifractal singularity function f(α) have been used to study variations in the genomes of a pathogenic bacteria Mycobacterium tuberculosis. Genomic sequences of M. tuberculosis isolates displayed significant variations in C(r) and f(α) reflecting inherent differences in sequences among isolates. M. tuberculosis isolates can be categorised into different subgroups based on sensitivity to drugs, these are DS (drug sensitive isolates), MDR (multi-drug resistant isolates) and XDR (extremely drug resistant isolates). C(r) follows significantly different scaling rules in different subgroups of isolates, but all the isolates follow one parameter scaling law. The richness in complexity of each subgroup can be quantified by the measures of multifractal parameters displaying a pattern in which XDR isolates have highest value and lowest for drug sensitive isolates. Therefore C(r) and multifractal functions can be useful parameters for analysis of genomic sequences. PMID:28440326
PRISIC, SLADJANA; HUSSON, ROBERT N.
The Mycobacterium tuberculosis genome encodes 11 serine/threonine protein kinases (STPKs). A similar number of two-component systems are also present, indicating that these two signal transduction mechanisms are both important in the adaptation of this bacterial pathogen to its environment. The M. tuberculosis phosphoproteome includes hundreds of Ser- and Thr-phosphorylated proteins that participate in all aspects of M. tuberculosis biology, supporting a critical role for the STPKs in regulating M. tuberculosis physiology. Nine of the STPKs are receptor type kinases, with an extracytoplasmic sensor domain and an intracellular kinase domain, indicating that these kinases transduce external signals. Two other STPKs are cytoplasmic and have regulatory domains that sense changes within the cell. Structural analysis of some of the STPKs has led to advances in our understanding of the mechanisms by which these STPKs are activated and regulated. Functional analysis has provided insights into the effects of phosphorylation on the activity of several proteins, but for most phosphoproteins the role of phosphorylation in regulating function is unknown. Major future challenges include characterizing the functional effects of phosphorylation for this large number of phosphoproteins, identifying the cognate STPKs for these phosphoproteins, and determining the signals that the STPKs sense. Ultimately, combining these STPK-regulated processes into larger, integrated regulatory networks will provide deeper insight into M. tuberculosis adaptive mechanisms that contribute to tuberculosis pathogenesis. Finally, the STPKs offer attractive targets for inhibitor development that may lead to new therapies for drug-susceptible and drug-resistant tuberculosis. PMID:25429354
The transport of d-alanine, d-glutamic acid, and d-valine in Mycobacterium smegmatis was compared quantitatively with that of their l-isomers. It appeared that the uptake of d-alanine was mediated by an active process displaying saturation kinetics characteristic of enzyme function, whereas the uptake of d-glutamic acid was accomplished by a passive process showing diffusion kinetics. Both processes were involved in the uptake of l-alanine, l-glutamic acid, d-valine, and l-valine. d-Valine competed with l-valine for entry into the cell through a single active process. d-Alanine and l-alanine also utilized the same active process, but the d-isomer could not enter the cell through the passive process. The passive process exhibited characteristics of diffusion, but was sensitive to sulfhydryl-blocking reagents and showed competition among structurally related amino acids. These last findings suggested that the passive process is a facilitated diffusion. PMID:5437732
Mostowy, Serge; Inwald, Jackie; Gordon, Steve; Martin, Carlos; Warren, Rob; Kremer, Kristin; Cousins, Debby; Behr, Marcel A.
Though careful consideration has been placed towards genetic characterization of tubercle bacillus isolates causing disease in humans, those causing disease predominantly among wild and domesticated mammals have received less attention. In contrast to Mycobacterium tuberculosis, whose host range is largely specific to humans, M. bovis and “M bovis-like” organisms infect a broad range of animal species beyond their most prominent host in cattle. To determine whether strains of variable genomic content are associated with distinct distributions of disease, the DNA contents of M. bovis or M. bovis-like isolates from a variety of hosts were investigated via Affymetrix GeneChip. Consistent with previous genomic analysis of the M. tuberculosis complex (MTC), large sequence polymorphisms of putative diagnostic and biological consequence were able to unambiguously distinguish interrogated isolates. The distribution of deleted regions indicates organisms genomically removed from M. bovis and also points to structured genomic variability within M. bovis. Certain genomic profiles spanned a variety of hosts but were clustered by geography, while others associated primarily with host type. In contrast to the prevailing assumption that M. bovis has broad host capacity, genomic profiles suggest that distinct MTC lineages differentially infect a variety of mammals. From this, a phylogenetic stratification of genotypes offers a predictive framework upon which to base future genetic and phenotypic studies of the MTC. PMID:16159772
Guerin, W.F.; Jones, G.E.
A Mycobacterium sp., designated strain BG1, able to utilize the polycyclic aromatic hydrocarbon phenanthrene as the sole carbon and energy source was isolated from estuarine sediment following enrichment with the hydrocarbon. Unlike other phenanthrene degraders, this bacterium degraded phenanthrene via 1-hydroxy-2-naphthoic acid without accumulating this or other aromatic intermediates, as shown by high-performance liquid chromatography. Degradation proceeded via meta cleavage of protocatechuic acid. Different nonionic surfactants (Tween compounds) solubilized the phenanthrene to different degrees and enhanced phenanthrene utilization. The order of enhancement, however, did not correlate perfectly with increased solubility, suggesting physiological as well as physicochemical effects of the surfactants. Plasmids of approximately 21, 58, and 77 megadaltons were detected in cells grown with phenanthrene but not in those which, after growth on nutrient media, lost the phenanthrene-degrading phenotype. Given that plasmid-mediated degradations of aromatic hydrocarbons generally occur via meta cleavages, it is of interest that the addition of pyruvate, a product of meta cleavage, supported rapid mineralization of phenanthrene in broth culture; succinate, a product of ortho cleavage, supported growth but completely repressed the utilization of phenanthrene. The involvement of plasmids may have given rise to the unusual degradation pattern that was observed.
Lamrabet, Otmane; Drancourt, Michel
Genetic engineering has been used for decades to mutate and delete genes in the Mycobacterium tuberculosis genome with the translational goal of producing attenuated mutants with conserved susceptibility to antituberculous antibiotics. The development of plasmids and mycobacteriophages that can transfer DNA into the M. tuberculosis chromosome has effectively overcome M. tuberculosis slow growth rate and the capsule and mycolic acid wall, which limit DNA uptake. The use of genetic engineering techniques has shed light on many aspects of pathogenesis mechanisms, including cellular growth, mycolic acid biosynthesis, metabolism, drug resistance and virulence. Moreover, such research gave clues to the development of new vaccines or new drugs for routine clinical practice. The use of genetic engineering tools is mainly based on the underlying concept that altering or reducing the M. tuberculosis genome could decrease its virulence. A contrario, recent post-genomic analyses indicated that reduced bacterial genomes are often associated with increased bacterial virulence and that M. tuberculosis acquired genes by lateral genetic exchange during its evolution. Therefore, ancestors utilizing genetic engineering to add genes to the M. tuberculosis genome may lead to new vaccines and the availability of M. tuberculosis isolates with increased susceptibility to antituberculous antibiotics.
Abgueguen, P; Pichard, E; Aubry, J
Buruli ulcer is a severe necrotizing cutaneous infection due to Mycobacterium ulcerans. The disease is currently expanding, especially in West Africa, and the WHO is supporting a vast research program to better understand the modes of transmission, to develop diagnostic methods, and to define specific treatment protocols. The disease transmission could be linked to environment and especially water striders. After M. ulcerans inoculation, cutaneous lesions appear, as broad painless ulcers, and thus ignored by patients. The production of mycolactone, a toxin, only virulence factor known at this time, is responsible for the cytotoxic effect on skin tissues. Complications may occur, especially super infections and more rarely bone involvement responsible for osteomyelitis. The prognosis is usually functional with sometimes severe sequels, and skin and tendinous retraction as well as amputation are frequent. The diagnosis is usually made on PCR but this is difficult in developing countries, direct examination is not very reliable, and culture is long and difficult. The disease often remains ignored and undiagnosed, leading to evolved clinical presentations and sequels. The treatment is not defined yet. It is often surgical exeresis with skin graft, not always efficient. Antibiotic combination protocols are under evaluation.
Corti, S; Chevalier, J; Cremieux, A
To evaluate the intracellular accumulation of norfloxacin in mycobacteria, two methods were used with Mycobacterium smegmatis. A radiometric method (K. V. Cundy, C. E. Fasching, K. E. Willard, and L. R. Peterson, J. Antimicrob. Chemother. 28:491-497, 1991) was used without great modification, but the fluorometric method (P. G. S. Mortimer and L. J. V. Piddock, J. Antimicrob. Chemother. 28:639-653, 1991) was changed considerably. Indeed, adsorption of the quinolone to the bacterial surface was characterized by measuring the level of accumulation of 0 degree C. Taking into account the adsorption, the pH of the washing buffer was increased from 7.0 to 9.0 to improve the desorption of norfloxacin from the cell surface. Both the fluorometric method, with the technical improvement, and the radiometric method could be used to estimate the intracellular accumulation of norfloxacin, which resulted from the difference between the whole uptake measured at 37 degrees C and the adsorption measured at 0 degrees C. A total of 35 ng of norfloxacin per mg of cells (dry weight) penetrated into the M. smegmatis cell, and the steady state was achieved in 5 min. Use of inhibitors of the proton motive force revealed that transport of norfloxacin was energy independent. Thus, the same mechanisms of quinolone accumulation that occur in eubacteria seem to occur in mycobacteria, at least in M. smegmatis.
Palmer, M V
Mycobacterium bovis is the cause of tuberculosis in animals and sometimes humans. Many developed nations have long-standing programmes to eradicate tuberculosis in livestock, principally cattle. As disease prevalence in cattle decreases these efforts are sometimes impeded by passage of M. bovis from wildlife to cattle. In epidemiological terms, disease can persist in some wildlife species, creating disease reservoirs, if the basic reproduction rate (R0) and critical community size (CCS) thresholds are achieved. Recognized wildlife reservoir hosts of M. bovis include the brushtail possum (Trichosurus vulpecula) in New Zealand, European badger (Meles meles) in Great Britain and Ireland, African buffalo (Syncerus caffer) in South Africa, wild boar (Sus scrofa) in the Iberian Peninsula and white-tailed deer (Odocoileus virginianus) in Michigan, USA. The epidemiological concepts of R0 and CCS are related to more tangible disease/pathogen characteristics such as prevalence, pathogen-induced pathology, host behaviour and ecology. An understanding of both epidemiological and disease/pathogen characteristics is necessary to identify wildlife reservoirs of M. bovis. In some cases, there is a single wildlife reservoir host involved in transmission of M. bovis to cattle. Complexity increases, however, in multihost systems where multiple potential reservoir hosts exist. Bovine tuberculosis eradication efforts require elimination of M. bovis transmission between wildlife reservoirs and cattle. For successful eradication identification of true wildlife reservoirs is critical, as disease control efforts are most effective when directed towards true reservoirs.
Delogu, Giovanni; Sali, Michela; Fadda, Giovanni
Tuberculosis (TB) still poses a major threat to mankind and during the last thirty years we have seen a recrudescence of the disease even in countries where TB was thought to be conquered. It is common opinion that more effective control tools such as new diagnostics, a new vaccine and new drugs are urgently needed to control the global pandemic, though the so far insufficient understanding of the Mycobacterium tuberculosis (Mtb) mechanism of pathogenesis is a major obstacle for the development of these control tools. In this review, we will summarize the recent advancement in the understanding of Mtb biology and on the pathogenesis of Mtb infection with emphasis on latent infection, with the change in paradigm of the last few years where the dichotomy between latent and active disease has been reconsidered in favor of a dynamic equilibrium between the host and the bacilli, encompassing a continuous spectrum of conditions that has been named TB spectrum. Implications for the diagnosis and control of disease in certain population will also be discussed. PMID:24363885
Basler, Tina; Brumshagen, Christina; Beineke, Andreas; Goethe, Ralph; Bäumer, Wolfgang
Mycobacterium avium ssp. paratuberculosis (MAP) causes Johne's disease, a chronic, granulomatous enteritis of ruminants. Dendritic cells (DC) of the gut are ideally placed to combat invading mycobacteria; however, little is known about their interaction with MAP. Here, we investigated the interaction of MAP and the closely related M. avium ssp. avium (MAA) with murine DC and the effect of infected macrophages on DC maturation. The infection of DC with MAP or MAA induced DC maturation, which differed to that of LPS as maturation was accompanied by higher production of IL-10 and lower production of IL-12. Treatment of maturing DC with supernatants from mycobacteria-infected macrophages resulted in impaired DC maturation, leading to a semi-mature, tolerogenic DC phenotype expressing low levels of MHCII, CD86 and TNF-α after LPS stimulation. Though the cells were not completely differentiated they responded with an increased IL-10 and a decreased IL-12 production. Using recombinant cytokines we provide evidence that the semi-mature DC phenotype results from a combination of secreted cytokines and released antigenic mycobacterial components of the infected macrophage. Our results indicate that MAP and MAA are able to subvert DC function directly by infecting and indirectly via the milieu created by infected macrophages.
Corti, S; Chevalier, J; Cremieux, A
To evaluate the intracellular accumulation of norfloxacin in mycobacteria, two methods were used with Mycobacterium smegmatis. A radiometric method (K. V. Cundy, C. E. Fasching, K. E. Willard, and L. R. Peterson, J. Antimicrob. Chemother. 28:491-497, 1991) was used without great modification, but the fluorometric method (P. G. S. Mortimer and L. J. V. Piddock, J. Antimicrob. Chemother. 28:639-653, 1991) was changed considerably. Indeed, adsorption of the quinolone to the bacterial surface was characterized by measuring the level of accumulation of 0 degree C. Taking into account the adsorption, the pH of the washing buffer was increased from 7.0 to 9.0 to improve the desorption of norfloxacin from the cell surface. Both the fluorometric method, with the technical improvement, and the radiometric method could be used to estimate the intracellular accumulation of norfloxacin, which resulted from the difference between the whole uptake measured at 37 degrees C and the adsorption measured at 0 degrees C. A total of 35 ng of norfloxacin per mg of cells (dry weight) penetrated into the M. smegmatis cell, and the steady state was achieved in 5 min. Use of inhibitors of the proton motive force revealed that transport of norfloxacin was energy independent. Thus, the same mechanisms of quinolone accumulation that occur in eubacteria seem to occur in mycobacteria, at least in M. smegmatis. PMID:8585727
Haas, Charles; Le Jeunne, Claire
In transplant recipients, immunosuppressive treatment affects cell-mediated immunity and increases the risk of tuberculosis. Tuberculosis may be transmitted by the donor organ or occur de novo, but such cases are rare. The vast majority of cases of active tuberculosis in transplant recipients result from reactivation of latent Mycobacterium tuberculosis infection. The incidence varies from one region of the globe to another, from 0.5-1.0% in North America, to 0.36-5.5% in Europe and 7.0-11.8% in India. The incidence of tuberculosis among transplant recipients is much higher than in the general population. Diabetes mellitus, renal impairment, systemic lupus erythematosus, chronic liver disease and AIDS all increase the risk of post-transplant tuberculosis. Extrapulmonary and disseminated forms are frequent in this setting. The diagnosis of tuberculosis in transplant recipients is often difficult, and treatment is frequently delayed. Tuberculosis can be life-threatening in such cases. Treatment is difficult because rifampicin is a cytochrome P450 inducer (leading to reduced levels of cyclosporine), and because the hepatotoxicity of isoniazid, rifampin and pyrazinamide is frequently increased in transplant recipients. Treatment of latent tuberculosis before transplantation markedly reduces the risk of developing active tuberculosis after transplantation.
Angala, Shiva Kumar; Belardinelli, Juan Manuel; Huc-Claustre, Emilie; Wheat, William H.; Jackson, Mary
Tuberculosis (TB) remains the second most common cause of death due to a single infectious agent. The cell envelope of Mycobacterium tuberculosis (Mtb), the causative agent of the disease in humans, is a source of unique glycoconjugates and the most distinctive feature of the biology of this organism. It is the basis of much of Mtb pathogenesis and one of the major causes of its intrinsic resistance to chemotherapeutic agents. At the same time, the unique structures of Mtb cell envelope glycoconjugates, their antigenicity and essentiality for mycobacterial growth provide opportunities for drug, vaccine, diagnostic and biomarker development, as clearly illustrated by recent advances in all of these translational aspects. This review focuses on our current understanding of the structure and biogenesis of Mtb glycoconjugates with particular emphasis on one of most intriguing and least understood aspect of the physiology of mycobacteria: the translocation of these complex macromolecules across the different layers of the cell envelope. It further reviews the rather impressive progress made in the last ten years in the discovery and development of novel inhibitors targeting their biogenesis. PMID:24915502
Cell-surface saccharides of Mycobacterium tuberculosis appear to be crucial factors in tuberculosis pathogenicity and could be useful antigens in tuberculosis immunodiagnosis. In the present study, we report the successful antigenic and immunogenic mimicry of mannose-containing cell-wall compounds of M. tuberculosis by dodecamer peptides identified by phage-display technology. Using a rabbit antiserum raised against M. tuberculosis cell-surface saccharides as a target for biopanning, peptides with three different consensus sequences were identified. Phage-displayed and chemically synthesized peptides bound to the anticarbohydrate antiserum. Rabbit antibodies elicited against the peptide QEPLMGTVPIRAGGGS recognize the mannosylated M. tuberculosis cell-wall antigens arabinomannan and lipoarabinomannan, and the glycosylated recombinant protein alanine/proline-rich antigen. Furthermore, antibodies were also able to react with mannan from Saccharomyces cerevisiae, but not with phosphatidylinositol dimannosides or arabinogalactan from mycobacteria. These results suggest that the immunogenic peptide mimics oligomannosidic epitopes. Interestingly, this report provides evidence that, in contrast with previously known carbohydrate mimotopes, no aromatic residues are necessary in a peptide sequence for mimicking unusual glycoconjugates synthesized by mycobacteria. The possible usefulness of the identified peptide mimotopes as surrogate reagents for immunodiagnosis and for the study of functional roles of the native non-peptide epitopes is discussed. PMID:15560754
Martinho, Anna Paula Vitirito; Franco, Marília Masello Junqueira; Ribeiro, Márcio Garcia; Perrotti, Isabella Belletti Mutt; Mangia, Simone Henriques; Megid, Jane; Vulcano, Luiz Carlos; Lara, Gustavo Henrique Batista; Santos, Adolfo Carlos Barreto; Leite, Clarice Queico Fujimura; de Carvalho Sanches, Osimar; Paes, Antonio Carlos
An uncommon disseminated Mycobacterium tuberculosis infection is described in a 12-year-old female dog presenting with fever, dyspnea, cough, weight loss, lymphadenopathy, melena, epistaxis, and emesis. The dog had a history of close contact with its owner, who died of pulmonary tuberculosis. Radiographic examination revealed diffuse radio-opaque images in both lung lobes, diffuse visible masses in abdominal organs, and hilar and mesenteric lymphadenopathy. Bronchial washing samples and feces were negative for acid-fast organisms. Polymerase chain reaction (PCR)-based species identification of bronchial washing samples, feces, and urine revealed M. tuberculosis using PCR-restriction enzyme pattern analysis-PRA. Because of public health concerns, which were worsened by the physical condition of the dog, euthanasia of the animal was recommended. Rough and tough colonies suggestive of M. tuberculosis were observed after microbiological culture of lung, liver, spleen, heart, and lymph node fragments in Löwenstein-Jensen and Stonebrink media. The PRA analysis enabled diagnosis of M. tuberculosis strains isolated from organs. PMID:23339199
Schwander, Stephan; Dheda, Keertan
The study of human pulmonary immunity against Mycobacterium tuberculosis (M.tb) provides a unique window into the biological interactions between the human host and M.tb within the broncho-alveolar microenvironment, the site of natural infection. Studies of bronchoalveolar cells (BACs) and lung tissue evaluate innate, adaptive, and regulatory immune mechanisms that collectively contribute to immunological protection or its failure. In aerogenically M.tb–exposed healthy persons lung immune responses reflect early host pathogen interactions that may contribute to sterilization, the development of latent M.tb infection, or progression to active disease. Studies in these persons may allow the identification of biomarkers of protective immunity before the initiation of inflammatory and disease-associated immunopathological changes. In healthy close contacts of patients with tuberculosis (TB) and during active pulmonary TB, immune responses are compartmentalized to the lungs and characterized by an exuberant helper T-cell type 1 response, which as suggested by recent evidence is counteracted by local suppressive immune mechanisms. Here we discuss how exploring human lung immunity may provide insights into disease progression and mechanisms of failure of immunological protection at the site of the initial host–pathogen interaction. These findings may also aid in the identification of new biomarkers of protective immunity that are urgently needed for the development of new and the improvement of current TB vaccines, adjuvant immunotherapies, and diagnostic technologies. To facilitate further work in this area, methodological and procedural approaches for bronchoalveolar lavage studies and their limitations are also discussed. PMID:21075901
Zerihun, Mulualem Adam; Berg, Vidar; Lyche, Jan L; Colquhoun, Duncan J; Poppe, Trygve T
Burbot Lota lota sampled from lakes Mjosa and Losna in southeastern Norway between 2005 and 2008 were found to be infected with Mycobacterium salmoniphilum at a culture-positive prevalence of 18.6 and 3.3%, respectively. The condition factor (CF) of mycobacteria-affected fish sampled from Mjøsa in 2008 was lower than the average CF of total sampled fish the same year. Externally visible pathological changes included skin ulceration, petechiae, exopthalmia and cataract. Internally, the infections were associated with capsulated, centrally necrotic granulomas, containing large numbers of acid-fast bacilli, found mainly in the mesenteries, spleen, heart and swim bladder. Mycobacterial isolates recovered on Middlebrook 7H10 agar were confirmed as M. salmoniphilum by phenotypical investigation and by partial sequencing of the 16S rRNA, rpoB and Hsp65genes as well as the internal transcribed spacer (ITS1) locus. This study adds burbot to the list of fish species susceptible to piscine mycobacteriosis and describes M. salmoniphilum infection in a non-salmonid fish for the first time.
Wu, Ting-Shu; Chiu, Cheng-Hsun; Yang, Chih-Hsun; Leu, Hsieh-Shong; Huang, Ching-Tai; Chen, Yi-Chieh; Wu, Tsu-Lan; Chang, Pi-Yueh; Su, Lin-Hui; Kuo, An-Jing; Chia, Ju-Hsin; Lu, Chia-Chen; Lai, Hsin-Chih
Introduction Mycobacterium marinum causes skin and soft tissue, bone and joint, and rare disseminated infections. In this study, we aimed to investigate the relationship between treatment outcome and antimicrobial susceptibility patterns. A total of 27 patients with M. marinum infections were enrolled. Methods Data on clinical characteristics and therapeutic methods were collected and analyzed. We also determined the minimum inhibitory concentrations of 7 antibiotics against 30 isolates from these patients. Results Twenty-seven patients received antimycobacterial agents with or without surgical debridement. Eighteen patients were cured, 8 failed to respond to treatment, and one was lost to follow-up. The duration of clarithromycin (147 vs. 28; p = 0.0297), and rifampicin (201 vs. 91; p = 0.0266) treatment in the cured patients was longer than that in the others. Surgical debridement was performed in 10 out of the 18 cured patients, and in 1 of another group (p = 0.0417). All the 30 isolates were susceptible to clarithromycin, amikacin, and linezolid; 29 (96.7%) were susceptible to ethambutol; 28 (93.3%) were susceptible to sulfamethoxazole; and 26 (86.7%) were susceptible to rifampicin. However, only 1 (3.3%) isolate was susceptible to doxycycline. Discussion Early diagnosis of the infection and appropriate antimicrobial therapy with surgical debridement are the mainstays of successful treatment. Clarithromycin and rifampin are supposed to be more effective agents. PMID:22911774
Schultz, John C.; Elbein, Alan D.
A particulate enzyme preparation from Mycobacterium smegmatis catalyzes the transfer of [14C]galactose from uridine 5′-diphosphate (UDP)-[14C]galactose and of [14C]glucose from UDP-[14C]glucose into chloroform-soluble products. The radioactive neutral lipids were purified by passage through diethylaminoethyl-cellulose, followed by thin-layer chromatography. When UDP-glucose was used as substrate, two major radioactive lipids were obtained; one had a hexose-glucose-glycerol ratio of 1:1:1. The second product had a hexose-glycerol ratio of 2:1 and, in addition to glucose, contained lesser amounts of mannose and galactose. With UDP-galactose as substrate, two radioactive products were observed that were chromatographically indistinguishable from the [14C]glucosyl-labeled mono- and diglycosyldiglyceride. Palmitate and oleate were the predominant fatty acid constituents in these lipids and were present in equimolar amounts in all of the products examined. The products have thus been identified as monoglycosyldiglyceride and a diglycosyldiglyceride containing glucose as the major hexose along with mannose and galactose. Properties of the galactosyl and glucosyl transferases are described. Images PMID:4808895
Galagan, James E.; Minch, Kyle; Peterson, Matthew; Lyubetskaya, Anna; Azizi, Elham; Sweet, Linsday; Gomes, Antonio; Rustad, Tige; Dolganov, Gregory; Glotova, Irina; Abeel, Thomas; Mahwinney, Chris; Kennedy, Adam D.; Allard, René; Brabant, William; Krueger, Andrew; Jaini, Suma; Honda, Brent; Yu, Wen-Han; Hickey, Mark J.; Zucker, Jeremy; Garay, Christopher; Weiner, Brian; Sisk, Peter; Stolte, Christian; Winkler, Jessica K.; Van de Peer, Yves; Iazzetti, Paul; Camacho, Diogo; Dreyfuss, Jonathan; Liu, Yang; Dorhoi, Anca; Mollenkopf, Hans-Joachim; Drogaris, Paul; Lamontagne, Julie; Zhou, Yiyong; Piquenot, Julie; Park, Sang Tae; Raman, Sahadevan; Kaufmann, Stefan H. E.; Mohney, Robert P.; Chelsky, Daniel; Moody, D. Branch; Sherman, David R.; Schoolnik, Gary K.
We have taken the first steps towards a complete reconstruction of the Mycobacterium tuberculosis regulatory network based on ChIP-Seq and combined this reconstruction with system-wide profiling of messenger RNAs, proteins, metabolites and lipids during hypoxia and re-aeration. Adaptations to hypoxia are thought to have a prominent role in M. tuberculosis pathogenesis. Using ChIP-Seq combined with expression data from the induction of the same factors, we have reconstructed a draft regulatory network based on 50 transcription factors. This network model revealed a direct interconnection between the hypoxic response, lipid catabolism, lipid anabolism and the production of cell wall lipids. As a validation of this model, in response to oxygen availability we observe substantial alterations in lipid content and changes in gene expression and metabolites in corresponding metabolic pathways. The regulatory network reveals transcription factors underlying these changes, allows us to computationally predict expression changes, and indicates that Rv0081 is a regulatory hub. PMID:23823726
Marsollier, L; Aubry, J; Saint-André, J-P; Robert, R; Legras, P; Manceau, A-L; Bourdon, S; Audrain, C; Carbonnelle, B
Mycobacterium ulcerans is an environmental pathogen concerning mainly the tropical countries; it is the causative agent of Buruli ulcer, which has become the third most important mycobacterial disease. In spite of water-linked epidemiological studies to identify the sources of M. ulcerans, the reservoir and the mode of transmission of this organism remain elusive. To determine the ecology and the mode of transmission of M. ulcerans we have set up an experimental model. This experimental model demonstrated that water bugs were able to transmit M. ulcerans by bites. In insects, the bacilli were localized exclusively within salivary glands, where it could both multiply contrary to other mycobacteria species. In another experimental study, we report that the crude extracts from aquatic plants stimulate in vitro the growth of M. ulcerans as much as the biofilm formation by M. ulcerans has been observed on aquatic plants. Given that the water bugs are essentially carnivorous, it is difficult to imagine a direct contact in the contamination of aquatic bugs and plants. It seems very likely that an intermediate host exists. In an endemic area of Daloa in Côte d'Ivoire, our observations were confirmed.
Mathema, Barun; Kurepina, Natalia; Yang, Guibin; Shashkina, Elena; Manca, Claudia; Mehaffy, Carolina; Bielefeldt-Ohmann, Helle; Ahuja, Shama; Fallows, Dorothy A.; Izzo, Angelo; Bifani, Pablo; Dobos, Karen; Kaplan, Gilla
Background. Evidence from genotype-phenotype studies suggests that genetic diversity in pathogens have clinically relevant manifestations that can impact outcome of infection and epidemiologic success. We studied 5 closely related Mycobacterium tuberculosis strains that collectively caused extensive disease (n = 862), particularly among US-born tuberculosis patients. Methods. Representative isolates were selected using population-based genotyping data from New York City and New Jersey. Growth and cytokine/chemokine response were measured in infected human monocytes. Survival was determined in aerosol-infected guinea pigs. Results. Multiple genotyping methods and phylogenetically informative synonymous single nucleotide polymorphisms showed that all strains were related by descent. In axenic culture, all strains grew similarly. However, infection of monocytes revealed 2 growth phenotypes, slower (doubling ∼55 hours) and faster (∼25 hours). The faster growing strains elicited more tumor necrosis factor α and interleukin 1β than the slower growing strains, even after heat killing, and caused accelerated death of infected guinea pigs (∼9 weeks vs 24 weeks) associated with increased lung inflammation/pathology. Epidemiologically, the faster growing strains were associated with human immunodeficiency virus and more limited in spread, possibly related to their inherent ability to induce a strong protective innate immune response in immune competent hosts. Conclusions. Natural variation, with detectable phenotypic changes, among closely related clinical isolates of M. tuberculosis may alter epidemiologic patterns in human populations. PMID:22315279
Chandanwale, Shirish S; Gulati, Ishita; Baravkar, Dadaso S; Shinde, Sumedha P; Mishra, Neha
Although breast tissue is the most resistant to tuberculosis, its incidence is increasing worldwide. High incidence of breast tuberculosis is presumed in India. The rapidly growing nontubercular mycobacteria, such as Mycobacterium fortuitum and Mycobacterium chelonae, are of increasing clinical importance because infections due to these organisms are often hospital acquired. The true incidence of M. fortuitum is unknown but it has been estimated to be between 4 and 6 cases per one million people. It causes skin or soft tissue infections following trauma or surgery. Breast infection with M. fortuitum is very uncommon. The most common clinical presentation of breast tuberculosis is a painless lump. Multiple lumps are rarely reported. The culture and molecular studies are the keystone for differentiation of various mycobacterium species. We report one such case of a 25-year-old female presenting with multiple painless lumps due to M. fortuitum infection in the left breast.
Krause, Kristian J; Reavill, Drury; Weldy, Scott H; Bradway, Daniel S
A 19-yr-old female African penguin (Spheniscus demersus) presented with labored breathing and anorexia. Radiographs revealed soft-tissue density lesions in the left lung fields and fluid in the right. The penguin died during the night. Postmortem examination demonstrated multiple granulomas in the lungs and air sacs. The right coelom was filled with opaque fluid. Histopathology of the lung, liver, kidney, and spleen identified Mycobacterium as a primary disease etiology. Large numbers of acid fast-positive, rod-shaped bacteria were recognized on tissue staining. Mycobacterium genavense was detected by polymerase chain reaction (PCR) using primers specific for the species. Further confirmation of M. genavense was accomplished using PCR with universal Mycobacterium spp. primers followed by sequencing of the amplicon obtained. To our knowledge, this is the first reported case of mycobacteriosis-and specifically M. genavense -in an African penguin. This case also demonstrates the similarities of presentation between the more commonly suspected and encountered aspergillosis and mycobacteriosis.
Sun, Yi-Chen; Wang, I-Jong; Chen, Wei-Li; Hu, Fung-Rong
We report successful treatment of a case of Mycobacterium abscessus keratitis after laser in situ keratomileusis (LASIK) with therapeutic lamellar keratectomy. A 34-year-old woman developed a 2 x 2 mm feathery infiltration within the interface inferior to the pupil margin with mild inflammation of the conjunctiva in her left eye 40 days after LASIK surgery. Bacterial culture from the infiltrates of the interface of the stromal bed revealed Mycobacterium abscessus. After combination antibiotic therapy including amikacin and ciprofoxacin was given for 6 weeks, infiltration persisted despite the development of necrosis in the flap tissue. Therapeutic lamellar keratectomy combined with flap removal was performed. No recurrence was found 1 year after the surgery. Therapeutic lamellar keratectomy with flap removal can provide an effective treatment modality for the management of post-LASIK Mycobacterium abscessus keratitis that is unresponsive to medical treatment.
Gonzalez-Perez, M N; Murcia, M I; Parra-Lopez, C; Blom, J; Tauch, A
Mycobacterium avium complex (MAC) contains clinically important nontuberculous mycobacteria worldwide and is the second largest medical complex in the Mycobacterium genus after the Mycobacterium tuberculosis complex. MAC comprises several species that are closely phylogenetically related but diverse regarding their host preference, course of disease, virulence and immune response. In this study we provided immunologic and virulence-related insights into the M. colombiense genome as a model of an opportunistic pathogen in the MAC. By using bioinformatic tools we found that M. colombiense has deletions in the genes involved in p-HBA/PDIM/PGL, PLC, SL-1 and HspX production, and loss of the ESX-1 locus. This information not only sheds light on our understanding the virulence mechanisms used by opportunistic MAC pathogens but also has great potential for the designing of species-specific diagnostic tools.
Velu, Prasad Palani; Fernandes, Susan E; Laurenson, Ian F; Noble, Donald D
A 65-year-old man presented with a six-month history of lethargy, weight loss and dry cough. He had a background of mild chronic obstructive pulmonary disease. Chest radiograph showed new right upper lobe cavitary opacification. Sputum cultures were acid-fast bacilli smear positive and yielded Mycobacterium marinum - a non-tuberculous mycobacterium (NTM) often found in aquatic environments and rarely associated with respiratory disease. The suspected source was silent aspiration of contaminated water, likely due to his initiating the siphon of his fish-tank by mouth. He completed a one-year course of rifampicin, ethambutol and clarithromycin, with negative repeat sputum mycobacteria cultures and radiological improvement. This case report demonstrates a successful approach to investigation and further management of Mycobacterium marinum pulmonary disease - a rare condition, particularly in immunocompetent individuals, with limited treatment guidelines. © The Author(s) 2016.
Cameselle, D; Hernández, J; Francès, A; Montenegro, T; Cañas, F; Borrego, L
We report a case of primary cutaneous infection by Mycobacterium haemophilum after the bite of an aquarium fish in a severely immunodepressed AIDS patient. Clinical features consisted in nodular and ulcerative lesions that followed a sporotrichoid pattern. Histological study of nodular lesions showed a granulomatous dermatitis with numerous acid-fast bacilli. The mycobacterium was identified 3 months later by genetic hybridization from a cultive in solid medium. Combined therapy with isoniazid, rifampin, clarithromycin, ethambutol, amikacin and ciprofloxacin resulted in complete resolution of the lesions. Infection by Mycobacterium haemophilum is a rare mycobacteriosis that usually affects immunodepressed patients. The most common clinical manifestations are cutaneous lesions but the development of sporotrichoid nodular lymphangitis is exceptional.
Shyur, Shyh Dar; Chu, Szu Hung; Wu, Yi Lei; Chang, Kuo Ming; Lee, Huei Chung
This report is of a healthy 3-year-old boy with bilateral parotitis caused by Mycobacterium chelonae. He was treated with antibiotics, but the symptoms did not improve. The biopsy pathology report revealed chronic caseating granulomatous inflammation. After 2 weeks, Mycobacterium chelonae was identified from the biopsy specimen culture. The antibiotics were changed to amikacin and clarithromycin, according to the susceptibility test. Two weeks later, he underwent debridement surgery. Only partial excision of the infected tissue was performed because of the possibility of facial nerve injury. After another 2 weeks of treatment with amikacin and clarithromycin, parotidectomy was performed. The patient then received a 6-month course of oral clarithromycin. At the 1-year follow up, he was well and without residual mass. His immunologic examinations were all within normal limits. This is the first report of bilateral parotitis caused by Mycobacterium chelonae in an immunocompetent boy in the English-language literature.
Derz, Kerstin; Klinner, Ulrich; Schuphan, Ingolf; Stackebrandt, Erko; Kroppenstedt, Reiner M
The taxonomic position of a polycyclic-aromatic-hydrocarbon-degrading bacterium, strain 17A3(T), isolated from contaminated soil was determined using a combination of phenotypic and genotypic properties. The isolate showed phenotypic properties that were diagnostic for species of the genus Mycobacterium. Comparative 16S rRNA gene sequence analysis assigned 17A3(T) to the 16S rRNA gene subgroup that contains Mycobacterium aurum, Mycobacterium austroafricanum, Mycobacterium vaccae and Mycobacterium vanbaalenii, but it could clearly be distinguished from these species using a combination of physiological, chemotaxonomic markers and internal rRNA gene spacer analyses. The data showed that strain 17A3(T) (=DSM 44605(T)=NRRL B-24244(T)) merits recognition as the type strain of a novel species of the genus Mycobacterium. The name Mycobacterium pyrenivorans sp. nov. is proposed for the species because of its ability to use pyrene as a sole source of carbon and energy.
Almost all nontuberculous mycobacteria (NTM) cause opportunistic infection. Therefore, the radiographic findings of NTM have a tendency of nonspecific patterns modifying the predisposing conditions or diseases and we could not extract species specific radiographic characterizations in that situations. In this review, the NTM cases without predisposing conditions or diseases are submitted essentially. Mycobacterium kansasii cases show more or less the same patterns with TB cases. Mycobacterium fortuitum case shows nonspecific consolidations. Mycobacterium xenopi case shows solitary cavity in the upper lobe area. Mycobacterium gordonae case shows the same cavitary pattern. Mycobacterium abscessus case shows widely scattered tree-in-bud appearance foci. Weak virulence NTM like as Mycobacterium xenopi or Mycobacterium gordonae may form solitary cavity without predisposing conditions. The pattern of bronchial wall thickening seems to be one of the specific findings with NTM pulmonary infection.
Palgrave, C J; Benato, L; Eatwell, K; Laurenson, I F; Smith, N H
Mycobacterium microti is a member of the Mycobacterium tuberculosis complex (MTC). M. microti is generally considered a pathogen of small rodents, although sporadic infections in a range of other mammals, including domestic animals and man, have been reported. While many human infections have been associated with immunosuppression, an increasing number of cases are being reported in immunocompetent patients. Two cases of M. microti infection in meerkats (Suricata suricatta) are reported. These are the first cases of mycobacterial disease to be described in meerkats outside Africa.
Johnson, Sadie; Brusasca, PierNatale; Lyashchenko, Konstantin; Spencer, John S.; Wiker, Harald G.; Bifani, Pablo; Shashkina, Elena; Kreiswirth, Barry; Harboe, Morten; Schluger, Neil; Gomez, Manuel; Gennaro, Maria Laura
MPT53 is a secreted protein of Mycobacterium tuberculosis. Southern transfer and hybridization showed mpt53 to be conserved in the M. tuberculosis complex and to have homology with DNA from Mycobacterium avium and other nontuberculous mycobacteria. However, anti-MPT53 polyclonal antibodies detected no antigen in the culture filtrates of M. avium and other nontuberculous mycobacteria. MPT53 of M. tuberculosis induced strong, tuberculosis-specific antibody responses in guinea pigs but induced no delayed-type hypersensitivity. Involvement in immune responses during human tuberculosis was very modest. PMID:11500477
Kaufman, Markus; Pal, Debnath; Eisenberg, David
Proteins up- and down- regulated in Mycobacterium tuberculosis grown under conditions mimicking infection are included in this database. It also includes information on proteins that are regulated by selected transcription factors or other regulatory proteins. The literature data provided here is complimentary to the databases provided by Michael Strong that include recent TB computational functional linkages and the Prolinks Database by Peter Bowers. The experimental condition, the experimental dataset and a literature reference will be displayed, including links to the computationally linked proteins in the Prolinks Database and the entry in the Mycobacterium tuberculosis Structural Genomics Database.[Copied from information at http://www.doe-mbi.ucla.edu/Services/MTBreg/
Morimoto, Kozo; Kazumi, Yuko; Maeda, Shinji; Yoshimori, Kozo; Yoshiyama, Takashi; Ogata, Hideo; Kurashima, Atsuyuki; Kudoh, Shoji
The DNA sequencing analyses of the 16S rRNA gene, rpoB and hsp65 were conducted to characterize six strains that had been identified as Mycobacterium xenopi by DNA-DNA hybridization (DDH) for past ten years in our hospital. The results revealed Mycobacterium heckeshornense infection in one of the six cases. A 47-year-old man, who had been treated for pneumonia, had pulmonary nontuberculous mycobacterial disease. The sputa from the patient were culture positive for mycobacterium in three times. And it was diagnosed as M. xenopiby DDH method. Chest X-ray showed fibrocavitary lesion in right upper lobe was successfully treated with clarithromycin for four weeks.
Lamy, Brigitte; Marchandin, Hélène; Hamitouche, Kamel; Laurent, Frédéric
A Gram-positive, rod-shaped acid-fast bacterium was isolated from a patient with a post-traumatic chronic skin abscess associated with osteitis. Morphological analysis, 16S rRNA, hsp65, sodA and rpoB gene sequence analysis, cell-wall fatty acid and mycolic acid composition analyses and biochemical tests showed that the isolate, designated ABO-M06(T), belonged to the genus Mycobacterium. Its phenotype was unique and genetic and phylogenetic findings suggest that strain ABO-M06(T) represents a novel species within the Mycobacterium fortuitum group. The name Mycobacterium setense sp. nov. is proposed for this novel species, with the type strain ABO-M06(T) (=CIP 109395(T)=DSM 45070(T)).
Monrabal Capilla, Maria
Esta tesis doctoral esta organizada en 5 capitulos y esta destinada al estudio de sistemas de Fe (II) que presentan el fenomeno de la transicion de espin a escala nanometrica. El capitulo 1 contiene una introduccion general sobre materiales moleculares multifuncionales, destacando aquellos ejemplos mas importantes. Por otro lado, se explicara el fenomeno de la transicion de espin, tratando aspectos conceptuales, los antecedentes mas importantes y la situacion actual. En el capitulo 2 se describen los diferentes procesos existentes para la obtencion de diferentes tipos de nanoparticulas. Ademas, se presenta la sintesis y caracterizacion de nanoparticulas del polimero de coordinacion unidimensional [Fe(Htrz)2(trz)]BF4, obtenidas mediante el metodo de micelas inversas. Estas nanoparticulas, con una estrecha distribucion de tamanos centrada alrededor de los 11 nm, presentan una transicion de espin muy abrupta, con un ancho ciclo de histeresis termica de unos 40K. En el capitulo 3 se describe el proceso de modificacion del tamano de las nanoparticulas descritas en el capitulo anterior, llevado a cabo variando la proporcion de surfactante/H2O en el medio. Ademas, con el objetivo de modificar las propiedades magneticas de las nanoparticulas obtenidas en el capitulo 2, se lleva a cabo la sintesis de nanoparticulas de polimeros de la misma familia del [Fe(Htrz)2(trz)]BF4. En concreto se sintetizaron 3 nuevos tipos de nanoparticulas basadas en el polimero [Fe(Htrz)1-x(NH2trz)x](ClO4)2, siendo x = 0.05, 0.15 y 0.3, en cada caso. Estas nanoparticulas siguen presentando una estrecha distribucion de tamanos y una transicion de espin muy abrupta y con un ancho ciclo de histeresis. Ademas, se observa que este ciclo se desplaza a temperaturas mas proximas a la temperatura ambiente a medida que se aumenta el porcentaje de 4-amino-1, 2, 4- triazol en la muestra. Pero al mismo tiempo se produce una disminucion de la anchura de este ciclo. Por ultimo, en este capitulo se presenta la
Djelouadji, Zoheira; Arnold, Catherine; Gharbia, Saheer; Raoult, Didier; Drancourt, Michel
Background Genotyping methods developed to survey the transmission dynamics of Mycobacterium tuberculosis currently rely on the interpretation of restriction and amplification profiles. Multispacer sequence typing (MST) genotyping is based on the sequencing of several intergenic regions selected after complete genome sequence analysis. It has been applied to various pathogens, but not to M. tuberculosis. Methods and Findings In M. tuberculosis, the MST approach yielded eight variable intergenic spacers which included four previously described variable number tandem repeat loci, one single nucleotide polymorphism locus and three newly evaluated spacers. Spacer sequence stability was evaluated by serial subculture. The eight spacers were sequenced in a collection of 101 M. tuberculosis strains from five phylogeographical lineages, and yielded 29 genetic events including 13 tandem repeat number variations (44.82%), 11 single nucleotide mutations (37.93%) and 5 deletions (17.24%). These 29 genetic events yielded 32 spacer alleles or spacer-types (ST) with an index of discrimination of 0.95. The distribution of M. tuberculosis isolates into ST profiles correlated with their assignment into phylogeographical lineages. Blind comparison of a further 93 M. tuberculosis strains by MST and restriction fragment length polymorphism-IS6110 fingerprinting and mycobacterial interspersed repetitive units typing, yielded an index of discrimination of 0.961 and 0.992, respectively. MST yielded 41 different profiles delineating 16 related groups and proved to be more discriminatory than IS6110-based typing for isolates containing <8 IS6110 copies (P<0.0003). MST was successfully applied to 7/10 clinical specimens exhibiting a Cts ≤ 42 cycles in internal transcribed spacer-real time PCR. Conclusions These results support MST as an alternative, sequencing-based method for genotyping low IS6110 copy-number M. tuberculosis strains. The M. tuberculosis MST database is freely available
Luh, Jeanne; Tong, Ning; Raskin, Lutgarde; Mariñas, Benito J
Batch experiments were performed to study the inactivation kinetics of Mycobacterium avium in the presence of monochloramine at 5-30 degrees C, pH 6-10, and 0.30-42.3 mg Cl2/ L. For each temperature and pH investigated, limiting high and low inactivation rates were observed for high and low disinfectant concentrations, respectively, within the range investigated. The rate of inactivation transitioned from high to low over a relatively narrow range of intermediate monochloramine concentrations. The observed temperature dependence of inactivation was consistent with an Arrhenius expression with activation energies of 58.0 and 71.7 kJ/mol for the high and low concentration ranges, respectively. The rate of inactivation increased with decreasing pH, consistent with trends reported for the reaction of monochloramine with protein thiols. Experiments performed at pH approximately 3.5 showed that dichloramine was a weaker disinfectant than monochloramine, and that its contribution to the overall inactivation of M. avium with combined chlorine was negligible at pH 6-10. A kinetic model incorporating disinfectant concentration, temperature, and pH effects was used to illustrate that monochloramine efficiency to inactivate M. avium in water could vary broadly from adequate (e.g., 99.9% inactivation efficiency in 32 min at 5 mg Cl2/L, pH 6, 30 degrees C) to impractical (e.g., 99.9% inactivation efficiency in 9 d at 1 mg Cl2/L, pH 9, 5 degrees C).
Bai, Xiyuan; Stitzel, Jerry A; Bai, An; Zambrano, Cristian A; Phillips, Matthew; Marrack, Philippa; Chan, Edward D
Pure nicotine impairs macrophage killing of Mycobacterium tuberculosis (MTB), but it is not known whether the nicotine component in cigarette smoke (CS) plays a role. Moreover, the mechanisms by which nicotine impairs macrophage immunity against MTB have not been explored. To neutralize the effects of nicotine in CS extract, we used a competitive inhibitor to the nicotinic acetylcholine receptor (nAChR)-mecamylamine-as well as macrophages derived from mice with genetic disruption of specific subunits of nAChR. We also determined whether nicotine impaired macrophage autophagy and whether nicotine-exposed T regulatory cells (Tregs) could subvert macrophage anti-MTB immunity. Mecamylamine reduced the CS extract increase in MTB burden by 43%. CS extract increase in MTB was also significantly attenuated in macrophages from mice with genetic disruption of either the α7, β2, or β4 subunit of nAChR. Nicotine inhibited autophagosome formation in MTB-infected THP-1 cells and primary murine alveolar macrophages, as well as increased the intracellular MTB burden. Nicotine increased migration of THP-1 cells, consistent with the increased number of macrophages found in the lungs of smokers. Nicotine induced Tregs to produce transforming growth factor-β. Naive mouse macrophages co-cultured with nicotine-exposed Tregs had significantly greater numbers of viable MTB recovered with increased IL-10 production and urea production, but no difference in secreted nitric oxide as compared with macrophages cocultured with unexposed Tregs. We conclude that nicotine in CS plays an important role in subverting macrophage control of MTB infection.
Sweetline Anne, N; Ronald, B S M; Kumar, T M A Senthil; Kannan, P; Thangavelu, A
Bovine tuberculosis continued to be a re-emerging problem in some countries especially in endemic areas due to the fact that human and animal health surveillance system is not adopted to diagnose the infection. This crisis can be attributed due to sharing of the same habitat especially in rural areas. In the present study, a total of 148 samples were collected from cattle for isolation over a period of 3 years from cattle with and without lesions, of which 67 isolates were obtained by culture. Fifty one isolates were identified as Mycobacterium tuberculosis complex (MTBC) by IS6110 PCR of which 43 (84.3%) were identified as M. tuberculosis and 08 (15.6%) were identified as M. bovis by using 12.7kb fragment multiplex PCR. Among this, 31 isolates which were positive for IS6110 PCR were subjected to spoligotyping and revealed 28 isolates belonging to MANU1 strain of M. tuberculosis. This study clearly indicates that high prevalence of M. tuberculosis than M. bovis in bovine was identified by means of culture and by molecular methods M. tuberculosis can affect cattle producing lesion in contradiction to the earlier thoughts. This study speculates that M. tuberculosis MANU1 strain infection in cattle could be due to spill over from human or other non specific hosts in tuberculosis endemic areas. Though bovine tuberculosis due to M. tuberculosis in cattle is not considered a serious threat worldwide, in countries where human TB is endemic, M. tuberculosis infection of cattle needs to be considered. Copyright © 2016 Elsevier B.V. All rights reserved.
Cristea, Paul Dan; Banica, Dorina; Tuduce, Rodica
As previously shown the conversion of nucleotide sequences into digital signals offers the possibility to apply signal processing methods for the analysis of genomic data. Genomic Signal Analysis (GSA) has been used to analyze large scale features of DNA sequences, at the scale of whole chromosomes, including both coding and non-coding regions. The striking regularities of genomic signals reveal restrictions in the way nucleotides and pairs of nucleotides are distributed along nucleotide sequences. Structurally, a chromosome appears to be less of a "plain text", corresponding to certain semantic and grammar rules, but more of a "poem", satisfying additional symmetry restrictions that evoke the "rhythm" and "rhyme". Recurrent patterns in nucleotide sequences are reflected in simple mathematical regularities observed in genomic signals. GSA has also been used to track pathogen variability, especially concerning their resistance to drugs. Previous work has been dedicated to the study of HIV-1, Clade F and Avian Flu. The present paper applies GSA methodology to study Mycobacterium tuberculosis (MT) rpoB gene variability, relevant to its resistance to antibiotics. Isolates from 50 Romanian patients have been studied both by rapid LightCycler PCR and by sequencing of a segment of 190-250 nucleotides covering the region of interest. The variability is caused by SNPs occurring at specific sites along the gene strand, as well as by inclusions. Because of the mentioned symmetry restrictions, the GS variations tend to compensate. An important result is that MT can act as a vector for HIV virus, which is able to retrotranscribe its specific genes both into human and MT genomes.
Molina-Torres, Carmen A.; Moreno-Torres, Elisa; Ocampo-Candiani, Jorge; Rendon, Adrian; Blackwood, Kym; Kremer, Kristin; Rastogi, Nalin; Welsh, Oliverio; Vera-Cabrera, Lucio
Although tuberculosis is still a public health problem in Mexico, there is little information about the genetic characteristics of the isolates. In the present study, we analyzed by spoligotyping 180 Mycobacterium tuberculosis clinical isolates from the urban area of Monterrey, Mexico, including drug-susceptible and drug-resistant isolates. The spoligotype patterns were compared with those in the international SITVIT2 spoligotyping database. Four isolates presented spoligotype patterns not found in the database (orphan types); the rest were distributed among 44 spoligo international types (SITs). SIT53 (clade T1) and SIT119 (clade X1) were predominant and included 43 (23.8%) and 28 (15.5%) of the isolates, respectively. In order to determine if there was a dominant spoligotype in the group of multidrug-resistant isolates, 37 of them were analyzed by IS6110-based restriction fragment length polymorphism assays, and scarce clustering of strains with more than five bands was observed. Fourteen isolates of this multidrug-resistant group presented four bands or less and were distributed in four SITs: SIT53 (n = 8), SIT92 (n = 3), SIT70 (n = 2), and SIT3038 (n = 1). When the molecular detection of mutations in the katG and rpoB genes were analyzed in these isolates with low copy numbers of IS6110, only two isolates shared the same IS6110, spoligotyping, and mutations patterns. When the distribution of the spoligotypes was analyzed by age cohort, SIT119 was predominantly found in patients 0 to 20 years old, especially in males, accounting for up to 40% of the isolates. In contrast, SIT53 was more prevalent in older females. This analysis demonstrates the variability of M. tuberculosis isolates in Monterrey and the partial dominance of SIT53 and SIT119 in that area of Mexico. PMID:19940048
García-Elorriaga, Guadalupe; Degollado-Estrada, Edgar; Villagómez-Ruiz, Alfredo; Cortés-Torres, Nancy; Arreguín-Reséndiz, Lilián; Del Rey-Pineda, Guillermo; González-Bonilla, César
Introducción: el objetivo de este artículo es Identificar y diferenciar el complejo MAC por PCR en pacientes con SIDA y micobacteriosis diseminada. Métodos: se llevó a cabo un estudio transversal para identificar MAC por biología molecular. Se sintetizaron dos conjuntos de iniciadores: MAV y MIN, para M. avium y M. intracellulare, respectivamente. El ADN total de células obtenidas de 29 aislados clínicos y muestras de suero de otros 24 pacientes con SIDA e infección micobacteriana diseminada fue extraído y se amplificó por PCR con los iniciadores MAV y MIN. Cada uno de los iniciadores MAV y MIN amplificó un segmento altamente específico de 1.3 kb del ADN homólogo, respectivamente. Resultados: veintinueve ADN de los aislados clínicos de MAC identificadas por Gen-Probe AccuProbes se amplificaron con los iniciadores MAV (M. avium). De las 24 muestras clínicas, 3 fueron positivas para M. avium y 6 para M. tuberculosis. Conclusiones: nuestros resultados demostraron que la técnica de PCR se puede aplicar para la diferenciación de M. avium y M. intracellulare por iniciadores específicos 16S rRNA. En pacientes con estadio avanzado de SIDA y en quienes se sospecha micobacteriosis diseminada, la presencia de anemia (incluso con cultivos negativos) fosfatasa alcalina elevada y una mediana de CD4 de 15.9/ml, se debe considerar seriamente el diagnóstico de infección por MAC; sugerimos que, de acuerdo con nuestros resultados, se justifica una estratificación más precisa de los pacientes en términos de sus recuentos de células T CD4.
Dhople, Arvind M.
In ominous projections issued by both U.S. Public Health Service and the World Health Organization, the epidemic of HIV infection will continue to rise more rapidly worldwide than predicted earlier. The AIDS patients are susceptible to diseases called opportunistic infections of which tuberculosis and Mycobacterium avium complex (MAC) infection are most common. This has created an urgent need to uncover new drugs for the treatment of these infections. In the seventies, NASA scientists at Goddard Space Flight Center, Greenbelt, MD, had adopted a biochemical indicator, adenosine triphosphate (ATP), to detect presence of life in extraterrestrial space. We proposed to develop ATP assay technique to determine sensitivity of antibacterial compounds against MAC and M. tuberculosis.
Wang, Joyce; McIntosh, Fiona; Radomski, Nicolas; Dewar, Ken; Simeone, Roxane; Enninga, Jost; Brosch, Roland; Rocha, Eduardo P.; Veyrier, Frédéric J.; Behr, Marcel A.
By phylogenetic analysis, Mycobacterium kansasii is closely related to Mycobacterium tuberculosis. Yet, although both organisms cause pulmonary disease, M. tuberculosis is a global health menace, whereas M. kansasii is an opportunistic pathogen. To illuminate the differences between these organisms, we have sequenced the genome of M. kansasii ATCC 12478 and its plasmid (pMK12478) and conducted side-by-side in vitro and in vivo investigations of these two organisms. The M. kansasii genome is 6,432,277 bp, more than 2 Mb longer than that of M. tuberculosis H37Rv, and the plasmid contains 144,951 bp. Pairwise comparisons reveal conserved and discordant genes and genomic regions. A notable example of genomic conservation is the virulence locus ESX-1, which is intact and functional in the low-virulence M. kansasii, potentially mediating phagosomal disruption. Differences between these organisms include a decreased predicted metabolic capacity, an increased proportion of toxin–antitoxin genes, and the acquisition of M. tuberculosis-specific genes in the pathogen since their common ancestor. Consistent with their distinct epidemiologic profiles, following infection of C57BL/6 mice, M. kansasii counts increased by less than 10-fold over 6 weeks, whereas M. tuberculosis counts increased by over 10,000-fold in just 3 weeks. Together, these data suggest that M. kansasii can serve as an image of the environmental ancestor of M. tuberculosis before its emergence as a professional pathogen, and can be used as a model organism to study the switch from an environmental opportunistic pathogen to a professional host-restricted pathogen. PMID:25716827
Choi, Go-Eun; Min, Ki-Nam; Won, Choul-Jae; Jeon, Kyeongman
Infections caused by Mycobacterium abscessus and Mycobacterium massiliense are on the rise among humans. Although macrolides, including clarithromycin (CLR) and azithromycin (AZM), are key antibiotics for the treatment of M. abscessus and M. massiliense infections, treatment regimens for these infections are still largely undefined. In this study, we evaluated the in vitro, ex vivo, and in vivo activities of moxifloxacin (MXF) in combination with macrolides against clinically isolated M. abscessus and M. massiliense strains. Overall, CLR, AZM, and MXF alone showed activity against both species in vitro, ex vivo, and in vivo. When MXF was combined with a macrolide against M. abscessus isolates, antagonism was observed in 65.4% (17/26) of the strains with CLR and 46.2% (12/26) of the strains with AZM in vitro as well as in 66.7% (10/15) of the strains with CLR and 40.0% (6/15) of the strains with AZM in macrophages as determined by the fractional inhibitory concentration index. In contrast, either indifferent or synergistic effects of the MXF-macrolide combinations were observed against only M. massiliense strains. Moreover, a murine infection model showed similar results. Antagonism between the MXF and macrolide combinations was observed in five out of seven M. abscessus strains, while indifferent and synergistic effects for these combinations were observed for three of the six M. massiliense strains tested, respectively. In conclusion, the activity of MXF in combination with a macrolide differed for M. abscessus and M. massiliense infections and the addition of MXF to macrolide therapy had no benefit for the treatment of M. abscessus infections. PMID:22564831
Khatri, Bhagwati; Fielder, Mark; Jones, Gareth; Newell, William; Abu-Oun, Manal; Wheeler, Paul R
Tuberculosis is a major human and animal disease of major importance worldwide. Genetically, the closely related strains within the Mycobacterium tuberculosis complex which cause disease are well-characterized but there is an urgent need better to understand their phenotypes. To search rapidly for metabolic differences, a working method using Biolog Phenotype MicroArray analysis was developed. Of 380 substrates surveyed, 71 permitted tetrazolium dye reduction, the readout over 7 days in the method. By looking for ≥5-fold differences in dye reduction, 12 substrates differentiated M. tuberculosis H37Rv and Mycobacterium bovis AF2122/97. H37Rv and a Beijing strain of M. tuberculosis could also be distinguished in this way, as could field strains of M. bovis; even pairs of strains within one spoligotype could be distinguished by 2 to 3 substrates. Cluster analysis gave three clear groups: H37Rv, Beijing, and all the M. bovis strains. The substrates used agreed well with prior knowledge, though an unexpected finding that AF2122/97 gave greater dye reduction than H37Rv with hexoses was investigated further, in culture flasks, revealing that hexoses and Tween 80 were synergistic for growth and used simultaneously rather than in a diauxic fashion. Potential new substrates for growth media were revealed, too, most promisingly N-acetyl glucosamine. Osmotic and pH arrays divided the mycobacteria into two groups with different salt tolerance, though in contrast to the substrate arrays the groups did not entirely correlate with taxonomic differences. More interestingly, these arrays suggested differences between the amines used by the M. tuberculosis complex and enteric bacteria in acid tolerance, with some hydrophobic amino acids being highly effective. In contrast, γ-aminobutyrate, used in the enteric bacteria, had no effect in the mycobacteria. This study proved principle that Phenotype MicroArrays can be used with slow-growing pathogenic mycobacteria and already has
Khatri, Bhagwati; Fielder, Mark; Jones, Gareth; Newell, William; Abu-Oun, Manal; Wheeler, Paul R.
Tuberculosis is a major human and animal disease of major importance worldwide. Genetically, the closely related strains within the Mycobacterium tuberculosis complex which cause disease are well-characterized but there is an urgent need better to understand their phenotypes. To search rapidly for metabolic differences, a working method using Biolog Phenotype MicroArray analysis was developed. Of 380 substrates surveyed, 71 permitted tetrazolium dye reduction, the readout over 7 days in the method. By looking for ≥5-fold differences in dye reduction, 12 substrates differentiated M. tuberculosis H37Rv and Mycobacterium bovis AF2122/97. H37Rv and a Beijing strain of M. tuberculosis could also be distinguished in this way, as could field strains of M. bovis; even pairs of strains within one spoligotype could be distinguished by 2 to 3 substrates. Cluster analysis gave three clear groups: H37Rv, Beijing, and all the M. bovis strains. The substrates used agreed well with prior knowledge, though an unexpected finding that AF2122/97 gave greater dye reduction than H37Rv with hexoses was investigated further, in culture flasks, revealing that hexoses and Tween 80 were synergistic for growth and used simultaneously rather than in a diauxic fashion. Potential new substrates for growth media were revealed, too, most promisingly N-acetyl glucosamine. Osmotic and pH arrays divided the mycobacteria into two groups with different salt tolerance, though in contrast to the substrate arrays the groups did not entirely correlate with taxonomic differences. More interestingly, these arrays suggested differences between the amines used by the M. tuberculosis complex and enteric bacteria in acid tolerance, with some hydrophobic amino acids being highly effective. In contrast, γ-aminobutyrate, used in the enteric bacteria, had no effect in the mycobacteria. This study proved principle that Phenotype MicroArrays can be used with slow-growing pathogenic mycobacteria and already has
Cheng, A; Liu, Y-C; Chen, M-L; Hung, C-C; Tsai, Y-T; Sheng, W-H; Liao, C-H; Hsueh, P-R; Chen, Y-C; Chang, S-C
A single strain of Mycobacterium massiliense (BRA 100), a subspecies of the Mycobacterium abscessus complex, has been responsible for an epidemic of post-surgical infections in Brazil. Outside Brazil, this is the first report to describe a single emerging strain of M. massiliense (TPE 101) associated with extrapulmonary infections. This phenomenon may be underestimated because sophisticated molecular typing of M. abscessus is not routinely performed. Our molecular epidemiology study was triggered by an outbreak investigation. Nine case isolates were grown from the surgical sites of nine mostly paediatric patients receiving operations from 2010 to 2011. All available non-duplicated isolates of M. abscessus during this period were obtained for comparison. Mycobacteria were characterized by multilocus sequence analysis (MLSA), repetitive sequence PCR (rep-PCR) and pulsed-field gel electrophoresis (PFGE). Of 58 isolates of M. abscessus overall, 56 were clinical isolates. MLSA identified 36 of the isolates as M. massiliense. All case isolates were indistinguishable by PFGE and named the TPE 101 pulsotype. Of the stored strains of M. abscessus, TPE 101 strains were over-represented among the control surgical wound (7/7, 100%) and subcutaneous tissue isolates (4/5, 80%) but rare among the respiratory isolates (1/16, 6%) and absent from external skin, ocular and environmental samples. In conclusion, a unique strain of M. massiliense has emerged as a distinctive pathogen causing soft tissue infections in Taiwan. Further study to identify whether this is due to an occult common source or to specific virulence factors dictating tissue tropism is warranted.
Michelet, Lorraine; de Cruz, Krystel; Zanella, Gina; Aaziz, Rachid; Bulach, Tabatha; Karoui, Claudine; Hénault, Sylvie; Joncour, Guy; Boschiroli, Maria Laura
We describe here 35 animal cases of tuberculosis due to Mycobacterium microti in France (2002-2014). Recently, molecular tools that overcome the difficulty of confirming infection by this potentially zoonotic agent have revealed an increasing number of cases, suggesting that its prevalence may have been underestimated.
Montero, Jose A; Alrabaa, Sally F; Wills, Todd S
A 30-year-old man with history of neonatal hydrocephalus requiring ventriculoperitoneal shunt placement presented with Mycobacterium abscessus shunt infection despite no shunt manipulation over 10 years prior to presentation. Cure was not achieved until complete removal of all CNS shunt foreign body was performed despite initial adequate antimicrobial therapy.
Shivashankar, Beechagondahalli Papanna; Umashankar, Kunigal Srinivasa; Nandini, Poojappa; Giridhar, Papanna; Byregowda, Somenahalli Munivenkatappa; Shrinivasa, Basavegowdanadoddi Marinaik
Postmortem examination of a wild Asian elephant at Rajiv Gandhi National Park, India, revealed nodular lesions, granulomas with central caseation, and acid-fast bacilli in the lungs. PCR and nucleotide sequencing confirmed the presence of Mycobacterium tuberculosis. This study indicates that wild elephants can harbor M. tuberculosis that can become fatal. PMID:28221114
Dan, J M; Crespo, M; Silveira, F P; Kaplan, R; Aslam, S
We present a report of extrapulmonary Mycobacterium bovis infection in a lung transplant recipient. M. bovis is acquired predominantly by zoonotic transmission, particularly from consumption of unpasteurized foods. We discuss epidemiologic exposure, especially as relates to the Mexico-US border, clinical characteristics, resistance profile, and treatment.
Mycobacterium avium (MA) is divided into four subspecies based primarily on host-range and consists of MA subsp. avium (birds), MA subsp. silvaticum (wood pigeons), MA subsp. paratuberculosis (broad, poorly-defined host range), and the recently described MA subsp. hominissuis (hu...
Travería, G E; Zumarraga, M; Etchechoury, I; Romano, M I; Cataldi, A; Pinedo, M F Alvarado; Pavlik, I; Pribylova, R; Romero, J R
We here identified for the first time the presence of Mycobacterium avium paratuberculosis (MAP) sheep (S) strain in Argentina. IS900 polymerase chain reaction (PCR) was positive. The S strain was compared with MAP cattle (C) strains by using IS1311 PCR-restriction endonuclease analysis (PCR-REA), multiplex PCR and restriction fragment length polymorphism (RFLP) analysis.
The study of host immune responses to Mycobacterium avium subsp. paratuberculosis (MAP) is complicated by a number of factors, including the protracted nature of the disease and the stealthy nature of the pathogen. Noted as one of the more fastidious mycobacteria, infection with MAP is often chara...
Mycobacterium avium subsp. paratuberculosis (MAP) infection in ruminants leads to a chronic and progressive enteric disease (Johne’s disease) that results in loss of intestinal function, poor body condition, and eventual death. Transmission is primarily through a fecal-oral route in neonates but con...
Rodríguez, Sabrina; Bezos, Javier; Romero, Beatriz; de Juan, Lucía; Álvarez, Julio; Castellanos, Elena; Moya, Nuria; Lozano, Francisco; Javed, M. Tariq; Sáez-Llorente, José L.; Liébana, Ernesto; Mateos, Ana; Domínguez, Lucas; Tuberculosis, Monitoring of Animal
Mycobacterium caprae is a pathogen that can infect animals and humans. To better understand the epidemiology of M. caprae, we spoligotyped 791 animal isolates. Results suggest infection is widespread in Spain, affecting 6 domestic and wild animal species. The epidemiology is driven by infections in caprids, although the organism has emerged in cattle. PMID:21392452
Garvey, Mark I; Phillips, Natalie; Bradley, Craig W; Holden, Elisabeth
Water samples taken from extracorporeal membrane oxygenator (ECMO) devices used at University Hospitals Birmingham yielded high total viable counts (TVCs) containing a variety of microorganisms, including M. chimaera. Disinfection resulted in the reduction of TVCs and eradication of Mycobacterium chimaera. Weekly disinfection and water sampling are required to manage the water quality in these devices. Infect Control Hosp Epidemiol 2017;38:1244-1246.
van Ingen, J; Hoefsloot, W; Buijtels, P C A M; Tortoli, E; Supply, P; Dekhuijzen, P N R; Boeree, M J; van Soolingen, D
In this study, nonchromogenic mycobacteria were isolated from pulmonary samples of three patients in the Netherlands. All isolates had identical, unique 16S rRNA gene and 16S-23S ITS sequences, which were closely related to those of Mycobacterium chimaera and Mycobacterium marseillense. The biochemical features of the isolates differed slightly from those of M. chimaera, suggesting that the isolates may represent a possible separate species within the Mycobacterium avium complex (MAC). However, the cell-wall mycolic acid pattern, analysed by HPLC, and the partial sequences of the hsp65 and rpoB genes were identical to those of M. chimaera. We concluded that the isolates represent a novel variant of M. chimaera. The results of this analysis have led us to question the currently used methods of species definition for members of the genus Mycobacterium, which are based largely on 16S rRNA or rpoB gene sequencing. Definitions based on a single genetic target are likely to be insufficient. Genetic divergence, especially in the MAC, yields strains that cannot be confidently assigned to a specific species based on the analysis of a single genetic target.
Background: Human Mycobacterium avium infections are only known to be acquired from environmental sources such as water and soil. We compared M. avium isolates from clinical and drinking water sources using molecular tools. Methods: M. avium was isolated from water samples colle...
Erardi, F X; Failla, M L; Falkinham, J O
A copper-tolerant Mycobacterium scrofulaceum strain was able to remove copper from culture medium by sulfate-dependent precipitation as copper sulfide. Such precipitation of copper sulfide was not observed in a derivative that lacks a 173-kilobase plasmid. In addition, the plasmid-carrying strain has a sulfate-independent copper resistance mechanism. PMID:3662522
García-Bocanegra, I.; Barranco, I.; Rodríguez-Gómez, I. M.; Pérez, B.; Gómez-Laguna, J.; Rodríguez, S.; Ruiz-Villamayor, E.; Perea, A.
We report three cases of tuberculosis in alpacas from Spain caused by Mycobacterium bovis. The animals revealed two different lesional patterns. Mycobacterial culture and PCR assay yielded positive results for M. bovis. Molecular typing of the isolates identified spoligotype SB0295 and identical variable-number tandem repeat (VNTR) allele sizes. PMID:20237097
Mitchison, Denis A
An important report by Bryk et al. in this issue of Cell Host & Microbe describes the properties of a rhodanine prodrug active against nonmultiplying Mycobacterium tuberculosis (Mtb). Considering the tolerance of nonreplicating Mtb to most currently available agents, such a drug could be a major addition to our antituberculosis arsenal and would greatly benefit control of the disease.
Michelet, Lorraine; de Cruz, Krystel; Zanella, Gina; Aaziz, Rachid; Bulach, Tabatha; Karoui, Claudine; Hénault, Sylvie; Joncour, Guy
We describe here 35 animal cases of tuberculosis due to Mycobacterium microti in France (2002–2014). Recently, molecular tools that overcome the difficulty of confirming infection by this potentially zoonotic agent have revealed an increasing number of cases, suggesting that its prevalence may have been underestimated. PMID:25540404
Background: Human Mycobacterium avium infections are only known to be acquired from environmental sources such as water and soil. We compared M. avium isolates from clinical and drinking water sources using molecular tools. Methods: M. avium was isolated from water samples colle...
Christensen, Joshua B.; Koeppe, John
Nontuberculosis mycobacterial cervical lymphadenitis is a relatively common disease in immunocompetent children but a rare disease in immunocompetent adults. We report the diagnosis and treatment of Mycobacterium avium complex cervical lymphadenitis in an adult female. Our evaluation of immune competence, including gamma interferon (IFN-γ) and interleukin-12 (IL-12) signaling, found no evidence of deficiency. PMID:20668140
García-Bocanegra, I; Barranco, I; Rodríguez-Gómez, I M; Pérez, B; Gómez-Laguna, J; Rodríguez, S; Ruiz-Villamayor, E; Perea, A
We report three cases of tuberculosis in alpacas from Spain caused by Mycobacterium bovis. The animals revealed two different lesional patterns. Mycobacterial culture and PCR assay yielded positive results for M. bovis. Molecular typing of the isolates identified spoligotype SB0295 and identical variable-number tandem repeat (VNTR) allele sizes.
Tabarsi, Payam; Baghaei, Parvaneh; Kashani, Babak Sharif; Adimi, Parisa; Novin, Atieh; Mansouri, Davood
Disseminated Mycobacterium kansasii infection is a rare infection in non-HIV patients. This research has uncovered a very rare manifestation of disseminated M. kansasii infection in a non-HIV patient with lung and pericardial involvement. Copyright © 2012. Published by Elsevier Ltd.
Mycobacterium avium (MA) is divided into four subspecies based primarily on host-range and consists of MA subsp. avium (birds), MA subsp. silvaticum (wood pigeons), MA subsp. paratuberculosis (broad, poorly-defined host range), and the recently described MA subsp. hominissuis (hu...
Santos, Ricardo; Fernandes, João; Fernandes, Nuno; Oliveira, Fernanda; Cadete, Manuela
Mycobacterium parascrofulaceum was found in Norris Geyser Basin, Yellowstone National Park, in a system composed of two acidic (pH 3.0) springs with temperatures between 56 degrees C at the source and 40 degrees C at the confluence of both springs. Growth and survival assays at 56 degrees C for 60 days were performed, confirming the origin of the strain.
Maeda, Shinji; Matsuoka, Masanori; Nakata, Noboru; Kai, Masanori; Maeda, Yumi; Hashimoto, Ken; Kimura, Hiroaki; Kobayashi, Kazuo; Kashiwabara, Yoshiko
Sequences of the folP1, rpoB, and gyrA genes were analyzed for 88 isolates of Mycobacterium leprae from leprosy patients in Japan, Haiti, Indonesia, Pakistan, and the Philippines. Thirteen isolates (14.8%) showed representative mutations in more than two genes, suggesting the emergence of multidrug-resistant M. leprae. PMID:11709358
Djelouadji, Zoheira; Raoult, Didier; Drancourt, Michel
Genome-scale analysis suggests that the last common ancestor of the Mycobacterium tuberculosis complex and Mycobacterium leprae diverged 36 million years ago, and members of the Mycobacterium tuberculosis complex differentiated 40,000 years ago. Analysis of palaeomicrobiological data from a 17,000-year-old sample from a bison and a 9000-year-old sample from a human being suggested that M tuberculosis preceded Mycobacterium bovis and related species. Whole-genome comparisons show that members of the M tuberculosis complex form a unique bacterial species with distinct ecotypes that are transmissible from any infected mammalian species to several others. Genomic deletions identified several M tuberculosis lineages that could be placed on a phylogeographical map, suggesting adaptation to local host populations. The degrees of transmissibility and virulence vary between M tuberculosis clones, with increased virulence mainly linked to gene loss in regulatory pathways. Such data suggest that most M tuberculosis clones have a restricted spreading capacity between the host population, allowing unpredictable bursts of highly transmissible, virulent, and successful clones, such as the east Asian (Beijing) clone. Advances in genomics have helped the development of molecular techniques for accurate identification of species and clones in the M tuberculosis complex, which is essential for tracing the source of infections.
Lantos, Ákos; Niemann, Stefan; Mezősi, László; Sós, Endre; Erdélyi, Károly; Dávid, Sándor; Parsons, Linda M.; Kubica, Tanja; Rüsch-Gerdes, Sabine
We report the first case of pulmonary tuberculosis caused by Mycobacterium bovis subsp. caprae in a captive Siberian tiger, an endangered feline. The pathogen was isolated from a tracheal aspirate obtained by bronchoscopy. This procedure provided a reliable in vivo diagnostic method in conjunction with conventional and molecular tests for the detection of mycobacteria. PMID:14718093
Simpson, Gary; Zimmerman, Ralph; Shashkina, Elena; Chen, Liang; Richard, Michael; Bradford, Carol M.; Dragoo, Gwen A.; Saiers, Rhonda L.; Peloquin, Charles A.; Daley, Charles L.; Planet, Paul; Narachenia, Apurva; Mathema, Barun
Although awareness of tuberculosis among captive elephants is increasing, antituberculosis therapy for these animals is not standardized. We describe Mycobacterium tuberculosis transmission between captive elephants based on whole genome analysis and report a successful combination treatment. Infection control protocols and careful monitoring of treatment of captive elephants with tuberculosis are warranted. PMID:28221115
Huaman, Moises A.; Ribes, Julie A.; Lohr, Kristine M.; Evans, Martin E.
Mycobacterium marinum infection has been historically associated with exposure to aquariums, swimming pools, fish, or other marine fauna. We present a case of M marinum left wrist tenosynovitis and elbow bursitis associated with a puncture injury and exposure to coal mine water in Illinois. PMID:26835478
Huaman, Moises A; Ribes, Julie A; Lohr, Kristine M; Evans, Martin E
Mycobacterium marinum infection has been historically associated with exposure to aquariums, swimming pools, fish, or other marine fauna. We present a case of M marinum left wrist tenosynovitis and elbow bursitis associated with a puncture injury and exposure to coal mine water in Illinois.
Gershman, Ken; Jensen, Bette; Arduino, Matthew J.; Yakrus, Mitchell A.; Cooksey, Robert C.; Srinivasan, Arjun
From February to October 2003, Mycobacterium goodii wound infections were identified among three patients who received surgical implants at a Colorado hospital. This report summarizes the investigation of the first reported nosocomial outbreak of M. goodii. Increased awareness is needed about the potential for nontuberculous mycobacteria to cause postoperative wound infections. PMID:15504281
Ivan, Mihaela; Dancer, Craig; Koehler, Ann P; Hobby, Michaela; Lease, Chris
An outbreak of skin abscesses occurred in Adelaide, Australia, in association with biomesotherapy, an alternative therapy practice. Mycobacterium chelonae was identified in 8 patient and 3 environmental samples. Our findings show M. chelonae infection can be associated with alternative therapies when infection-control breaches occur. Tighter regulations of alternative therapy practices are needed.
Pecsi, Ildiko; Hirmondo, Rita; Brown, Amanda C.; Lopata, Anna; Parish, Tanya; Vertessy, Beata G.; Tóth, Judit
Thymidine biosynthesis is essential in all cells. Inhibitors of the enzymes involved in this pathway (e.g. methotrexate) are thus frequently used as cytostatics. Due to its pivotal role in mycobacterial thymidylate synthesis dUTPase, which hydrolyzes dUTP into the dTTP precursor dUMP, has been suggested as a target for new antitubercular agents. All mycobacterial genomes encode dUTPase with a mycobacteria-specific surface loop absent in the human dUTPase. Using Mycobacterium smegmatis as a fast growing model for Mycobacterium tuberculosis, we demonstrate that dUTPase knock-out results in lethality that can be reverted by complementation with wild-type dUTPase. Interestingly, a mutant dUTPase gene lacking the genus-specific loop was unable to complement the knock-out phenotype. We also show that deletion of the mycobacteria-specific loop has no major effect on dUTPase enzymatic properties in vitro and thus a yet to be identified loop-specific function seems to be essential within the bacterial cell context. In addition, here we demonstrated that Mycobacterium tuberculosis dUTPase is fully functional in Mycobacterium smegmatis as it rescues the lethal knock-out phenotype. Our results indicate the potential of dUTPase as a target for antitubercular drugs and identify a genus-specific surface loop on the enzyme as a selective target. PMID:22655049
de Souza Figueiredo, Eduardo Eustáquio; Silvestre, Flávia Galindo; Campos, Wilma Neres; Furlanetto, Leone Vinícius; Medeiros, Luciana; Lilenbaum, Walter; Fonseca, Leila Sousa; Silva, Joab Trajano; Paschoalin, Vânia Margaret Flosi
Isolates from suggestive bovine tuberculosis lesions were tested by a multiplex polymerase chain reaction (m-PCR) targeting for RvD1Rv2031c and IS6110 sequences, specific for M. bovis and Mycobacterium tuberculosis complex respectively. The m-PCR successfully identified as M. bovis 88.24% of the isolates. PMID:24031349
Zachariah, Arun; Pandiyan, Jeganathan; Madhavilatha, G.K.; Mundayoor, Sathish; Chandramohan, Bathrachalam; Sajesh, P.K.; Santhosh, Sam
We tested 3 ild Asian elephants (Elephas maximus) in southern India and confirmed infection in 3 animals with Mycobacterium tuberculosis, an obligate human pathogen, by PCR and genetic sequencing. Our results indicate that tuberculosis may be spilling over from humans (reverse zoonosis) and emerging in wild elephants. PMID:28221104
Moritz, Donna C; Harrington, Amanda T; Slavin, Konstantin; Gomez, Christy; Jarrett, Olamide D
Devise-related infections after deep brain stimulator implantation are not uncommon. However, infections due to mycobacteria have not been reported in the medical literature. We describe the first reported case of DBS infection due to a novel rapidly growing mycobacteria, most closely resembling Mycobacterium goodii, by rpoB gene sequencing.
Tu, Yiling; Zeng, Xiaohong; Li, Hui; Zheng, Rongrong; Xu, Ye; Li, Qingge
A novel strip array was developed for a nine-spacer spoligotyping scheme of Mycobacterium tuberculosis complex (MTBC). The new method was evaluated using 211 MTBC isolates and the results were fully concordant with the traditional spoligotyping approach. The strip array proved to be rapid and convenient for spoligotyping of MTBC.
Escalante-Fuentes, Wendy; Ocampo-Garza, Sonia S.; Ocampo-Candiani, Jorge; Molina-Torres, Carmen A.; Avanzi, Charlotte; Benjak, Andrej; Busso, Philippe; Singh, Pushpendra; Cole, Stewart T.
The frequency of infection caused by the recently described pathogen Mycobacterium lepromatosis is unknown. Here, we describe the demographics, clinical characteristics, and therapeutic outcomes of five lepromatous leprosy patients suffering from M. lepromatosis infection in Nuevo Léon, Mexico. Diagnosis was facilitated by a new highly specific PCR procedure. PMID:25809978
Issa, Rahizan; Abdul, Hatijah; Hashim, Siti Hasmah; Seradja, Valentinus H; Shaili, Nurul 'Aishah; Hassan, Nurul Akma Mohd
A quantitative real-time PCR (qPCR) followed by high resolution melting (HRM) analysis was developed for the differentiation of Mycobacterium species. Rapid differentiation of Mycobacterium species is necessary for the effective diagnosis and management of tuberculosis. In this study, the 16S rRNA gene was tested as the target since this has been identified as a suitable target for the identification of mycobacteria species. During the temperature gradient and primer optimization process, the melting peak (Tm) analysis was determined at a concentration of 50 ng DNA template and 0.3, 0.4 and 0.5 µM primer. The qPCR assay for the detection of other mycobacterial species was done at the Tm and primer concentration of 62 °C and 0.4 µM, respectively. The HRM analysis generated cluster patterns that were specific and sensitive to distinguished small sequence differences of the Mycobacterium species. This study suggests that the 16S rRNA-based real-time PCR followed by HRM analysis produced unique cluster patterns for species of Mycobacterium and could differentiate the closely related mycobacteria species. © 2014 The Authors.
Albini, S; Mueller, S; Bornand, V; Gutzwiller, M E Ricklin; Burnand, C; Hüssy, D; Abril, C; Reitt, K; Korczak, B M; Miserez, R
Fast growing mycobacteria are saprophytic bacteria that prevail in water and soil. They are opportunistic pathogens and may cause various infections if gaining entry into the body through a trauma. We herein describe the clinical presentation, pathology and diagnosis of the first case of cutaneous atypical mycobacteriosis due to Mycobacterium massiliense in a cat.
Yamazoe, Masami; Takahashi, Ryuji
The patient was a 56-year-old man, who was found to have a cavitary lesion surrounded by small nodules in the left upper lobe (S(1+2)) on the chest computed tomography (CT) scan prior to surgery for oropharyngeal cancer. Both sputum and bronchial lavage smears for acid-fast bacilli were positive, but a polymerase chain reaction for Mycobacterium tuberculosis and Mycobacterium avium complex failed to identify the isolates. Mycobacterium species were cultured in 4 weeks. Mycobacterium branderi was identified by determining the nucleic acid sequences of the 16S ribosomal RNA (16S rRNA) and RNA polymerase B (rpoB) genes. Chemotherapy and radiotherapy for esophageal cancer were started 5 months after the surgery for oropharyngeal cancer. The patient developed fever during the second round of chemotherapy. After chemotherapy and radiotherapy, the wall of the cavitary lesion thickened and a consolidation shadow was noted in the lower portion of the cavitary lesion on the chest CT scan. Combined therapy with clarithromycin, ciprofloxacin, and ethionamide improved the clinical symptoms; further, the abnormal chest shadows disappeared, and the sputum smears and cultures for acid-fast bacilli were negative. Although, currently, there are no recommended therapeutic regimens for pulmonary nontuberculous mycobacteriosis caused by M. branderi, combined therapy including the drugs used in this case may have a beneficial effect on this disease.
Zanoni, R G; Florio, D; Fioravanti, M L; Rossi, M; Prearo, M
The occurrence of Mycobacterium spp. in freshwater and marine ornamental fish was studied in Italy from June 2002 to May 2005. Two surveys were carried out, one of aquarium fish sent to the Laboratory for diagnosis, and the other of prevalence of infection by mycobacteria in ornamental fish imported into Italy. Bacterial isolation was carried out from the spleen, kidney and liver, and the isolates were subsequently identified by biochemical tests. In the first survey, 387 fish were examined and Mycobacterium spp. were isolated from 181 (46.8%) fish. In the second survey 127 batches of ornamental fish from different countries were examined. Mycobacterium spp. were isolated from 38 (29.9%) batches. The following species were found: M. fortuitum, M. peregrinum, M. chelonae, M. abscessus, M. marinum, M. gordonae, M. nonchromogenicum and M. interjectum. There was a high prevalence of infection independent of the presence of macroscopic lesions. Mycobacterium fortuitum and M. chelonae were more prevalent than M. marinum in the samples examined.
... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Mycobacterium tuberculosis immunofluorescent reagents. 866.3370 Section 866.3370 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents...
... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Mycobacterium tuberculosis immunofluorescent reagents. 866.3370 Section 866.3370 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents...
Zachariah, Arun; Pandiyan, Jeganathan; Madhavilatha, G K; Mundayoor, Sathish; Chandramohan, Bathrachalam; Sajesh, P K; Santhosh, Sam; Mikota, Susan K
We tested 3 ild Asian elephants (Elephas maximus) in southern India and confirmed infection in 3 animals with Mycobacterium tuberculosis, an obligate human pathogen, by PCR and genetic sequencing. Our results indicate that tuberculosis may be spilling over from humans (reverse zoonosis) and emerging in wild elephants.
Ramarokoto, H; Andrianasolo, D; Rasolonavalona, T; Ramaroson, F; Razafitsiarovana, I; Vincent, V; Ratsimba, L; Rasolofo Razanamparany, V
We report a chronic case of pulmonary tuberculosis in a Malagasy citizen from Antsohihy (West of Madagascar), who was infected with a multi-drug resistant Mycobacterium bovis strain. This is the first case reported of the isolation of such a strain in Madagascar.
Introduction. Cattle infected with Mycobacterium bovis, the causative agent of bovine tuberculosis and a relevant zoonosis to humans, may be sent to slaughter before diagnosis of infection because of slow multiplication of the pathogen. Purpose. This study evaluates multiple processing interventi...
Objective. Mycobacterium bovis is the causative agent of bovine tuberculosis, a relevant zoonosis that can spread to humans through inhalation or by ingestion. M. bovis multiplies slowly, so infected animals may be sent to slaughter during the early stages of the disease before diagnosis and when ...
Asmar, Shady; Rascovan, Nicolás; Robert, Catherine
Mycobacterium acapulcensis is a rapidly growing scotochromogenic acid-fast bacillus. The draft genome of M. acapulcensis CSURP1424 comprises 5,290,974 bp, exhibiting a 66.67% G+C content, 4,870 protein-coding genes, and 71 predicted RNA genes. PMID:27516522
Bermejo, Joaquín; Pascale, María Laura; Borda, Noemí; Notario, Rodolfo
We describe two cases of surgical site infections due to Mycobacterium fortuitum after plastic surgery. Both patients were assisted by the same surgeon on differents hospitals. Both patients received combined antibiotic treatment and surgical debridement or multiple aspirative punctures. The final evolutions were satisfactory.
Absence of Mycobacterium intracellulare and presence of Mycobacterium chimaera in household water and biofilm samples of patients in the United States with Mycobacterium avium complex respiratory disease.
Wallace, Richard J; Iakhiaeva, Elena; Williams, Myra D; Brown-Elliott, Barbara A; Vasireddy, Sruthi; Vasireddy, Ravikiran; Lande, Leah; Peterson, Donald D; Sawicki, Janet; Kwait, Rebecca; Tichenor, Wellington S; Turenne, Christine; Falkinham, Joseph O
Recent studies have shown that respiratory isolates from pulmonary disease patients and household water/biofilm isolates of Mycobacterium avium could be matched by DNA fingerprinting. To determine if this is true for Mycobacterium intracellulare, household water sources for 36 patients with Mycobacterium avium complex (MAC) lung disease were evaluated. MAC household water isolates from three published studies that included 37 additional MAC respiratory disease patients were also evaluated. Species identification was done initially using nonsequencing methods with confirmation by internal transcribed spacer (ITS) and/or partial 16S rRNA gene sequencing. M. intracellulare was identified by nonsequencing methods in 54 respiratory cultures and 41 household water/biofilm samples. By ITS sequencing, 49 (90.7%) respiratory isolates were M. intracellulare and 4 (7.4%) were Mycobacterium chimaera. In contrast, 30 (73%) household water samples were M. chimaera, 8 (20%) were other MAC X species (i.e., isolates positive with a MAC probe but negative with species-specific M. avium and M. intracellulare probes), and 3 (7%) were M. avium; none were M. intracellulare. In comparison, M. avium was recovered from 141 water/biofilm samples. These results indicate that M. intracellulare lung disease in the United States is acquired from environmental sources other than household water. Nonsequencing methods for identification of nontuberculous mycobacteria (including those of the MAC) might fail to distinguish closely related species (such as M. intracellulare and M. chimaera). This is the first report of M. chimaera recovery from household water. The study underscores the importance of taxonomy and distinguishing the many species and subspecies of the MAC.
Absence of Mycobacterium intracellulare and Presence of Mycobacterium chimaera in Household Water and Biofilm Samples of Patients in the United States with Mycobacterium avium Complex Respiratory Disease
Iakhiaeva, Elena; Williams, Myra D.; Brown-Elliott, Barbara A.; Vasireddy, Sruthi; Vasireddy, Ravikiran; Lande, Leah; Peterson, Donald D.; Sawicki, Janet; Kwait, Rebecca; Tichenor, Wellington S.; Turenne, Christine; Falkinham, Joseph O.
Recent studies have shown that respiratory isolates from pulmonary disease patients and household water/biofilm isolates of Mycobacterium avium could be matched by DNA fingerprinting. To determine if this is true for Mycobacterium intracellulare, household water sources for 36 patients with Mycobacterium avium complex (MAC) lung disease were evaluated. MAC household water isolates from three published studies that included 37 additional MAC respiratory disease patients were also evaluated. Species identification was done initially using nonsequencing methods with confirmation by internal transcribed spacer (ITS) and/or partial 16S rRNA gene sequencing. M. intracellulare was identified by nonsequencing methods in 54 respiratory cultures and 41 household water/biofilm samples. By ITS sequencing, 49 (90.7%) respiratory isolates were M. intracellulare and 4 (7.4%) were Mycobacterium chimaera. In contrast, 30 (73%) household water samples were M. chimaera, 8 (20%) were other MAC X species (i.e., isolates positive with a MAC probe but negative with species-specific M. avium and M. intracellulare probes), and 3 (7%) were M. avium; none were M. intracellulare. In comparison, M. avium was recovered from 141 water/biofilm samples. These results indicate that M. intracellulare lung disease in the United States is acquired from environmental sources other than household water. Nonsequencing methods for identification of nontuberculous mycobacteria (including those of the MAC) might fail to distinguish closely related species (such as M. intracellulare and M. chimaera). This is the first report of M. chimaera recovery from household water. The study underscores the importance of taxonomy and distinguishing the many species and subspecies of the MAC. PMID:23536397
Rocchetti, Talita T; Silbert, Suzane; Gostnell, Alicia; Kubasek, Carly; Campos Pignatari, Antonio C; Widen, Raymond
A new multiplex PCR test was designed to detect Mycobacterium chelonae, Mycobacterium abscessus group, and Mycobacterium fortuitum complex on the BD MAX System. A total of 197 clinical samples previously submitted for mycobacterial culture were tested using the new protocol. Samples were first treated with proteinase K, and then each sample was inoculated into the BD MAX Sample Buffer Tube. Extraction and multiplex PCR were performed by the BD MAX System, using the BD MAX ExK TNA-3 extraction kit and BD TNA Master Mix, along with specific in-house designed primers and probes for each target. The limit of detection of each target, as well as specificity, was evaluated. Of 197 clinical samples included in this study, 133 were positive and 60 were negative for mycobacteria by culture, and another 4 negative samples were spiked with M. chelonae ATCC 35752. The new multiplex PCR on the BD MAX had 97% concordant results with culture for M. abscessus group detection, 99% for M. chelonae, and 100% for M. fortuitum complex. The new multiplex PCR test performed on the BD MAX System proved to be a sensitive and specific test to detect M. chelonae, M. abscessus group, and M. fortuitum complex by real-time PCR on an automated sample-in results-out platform. Copyright © 2017 American Society for Investigative Pathology and the Association for Molecular Pathology. Published by Elsevier Inc. All rights reserved.
Fluorescent acid-fast microscopy for measuring phagocytosis of Mycobacterium avium, Mycobacterium intracellulare, and Mycobacterium scrofulaceum by Tetrahymena pyriformis and their intracellular growth.
Strahl, E D; Gillaspy, G E; Falkinham, J O
Fluorescent acid-fast microscopy (FAM) was used to enumerate intracellular Mycobacterium avium, Mycobacterium intracellulare, and Mycobacterium scrofulaceum in the ciliated phagocytic protozoan Tetrahymena pyriformis. There was a linear relationship between FAM and colony counts of M. avium cells both from cultures and within protozoa. The Ziehl-Neelsen acid-fast stain could not be used to enumerate intracellular mycobacteria because uninfected protozoa contained acid-fast, bacterium-like particles. Starved, 7-day-old cultures of T. pyriformis transferred into fresh medium readily phagocytized M. avium, M. intracellulare, and M. scrofulaceum. Phagocytosis was rapid and reached a maximum in 30 min. M. avium, M. intracellulare, and M. scrofulaceum grew within T. pyriformis, increasing by factors of 4- to 40-fold after 5 days at 30 degrees C. Intracellular M. avium numbers remained constant over a 25-day period of growth (by transfer) of T. pyriformis. Intracellular M. avium cells also survived protozoan encystment and germination. The growth and viability of T. pyriformis were not affected by mycobacterial infection. The results suggest that free-living phagocytic protozoa may be natural hosts and reservoirs for M. avium, M. intracellulare, and M. scrofulaceum.
Brosch, R.; Gordon, S. V.; Marmiesse, M.; Brodin, P.; Buchrieser, C.; Eiglmeier, K.; Garnier, T.; Gutierrez, C.; Hewinson, G.; Kremer, K.; Parsons, L. M.; Pym, A. S.; Samper, S.; van Soolingen, D.; Cole, S. T.
The distribution of 20 variable regions resulting from insertion-deletion events in the genomes of the tubercle bacilli has been evaluated in a total of 100 strains of Mycobacterium tuberculosis, Mycobacterium africanum, Mycobacterium canettii, Mycobacterium microti, and Mycobacterium bovis. This approach showed that the majority of these polymorphisms did not occur independently in the different strains of the M. tuberculosis complex but, rather, resulted from ancient, irreversible genetic events in common progenitor strains. Based on the presence or absence of an M. tuberculosis specific deletion (TbD1), M. tuberculosis strains can be divided into ancestral and “modern” strains, the latter comprising representatives of major epidemics like the Beijing, Haarlem, and African M. tuberculosis clusters. Furthermore, successive loss of DNA, reflected by region of difference 9 and other subsequent deletions, was identified for an evolutionary lineage represented by M. africanum, M. microti, and M. bovis that diverged from the progenitor of the present M. tuberculosis strains before TbD1 occurred. These findings contradict the often-presented hypothesis that M. tuberculosis, the etiological agent of human tuberculosis evolved from M. bovis, the agent of bovine disease. M. canettii and ancestral M. tuberculosis strains lack none of these deleted regions, and, therefore, seem to be direct descendants of tubercle bacilli that existed before the M. africanum→M. bovis lineage separated from the M. tuberculosis lineage. This observation suggests that the common ancestor of the tubercle bacilli resembled M. tuberculosis or M. canettii and could well have been a human pathogen already. PMID:11891304
Defining genetic diversity in the wake of the release of several Mycobacterium avium subsp. paratuberculosis (MAP) genome sequences has become a major emphasis in the molecular biology and epidemiology of Johne’s disease research. These data can now be used to define the extent of strain diversity ...
Cousins, Debby V; Bastida, Ricardo; Cataldi, Angel; Quse, Viviana; Redrobe, Sharon; Dow, Sue; Duignan, Padraig; Murray, Alan; Dupont, Christine; Ahmed, Niyaz; Collins, Des M; Butler, W Ray; Dawson, David; Rodríguez, Diego; Loureiro, Julio; Romano, Maria Isabel; Alito, A; Zumarraga, M; Bernardelli, Amelia
A comparison of Mycobacterium tuberculosis complex isolates from seals (pinnipeds) in Australia, Argentina, Uruguay, Great Britain and New Zealand was undertaken to determine their relationships to each other and their taxonomic position within the complex. Isolates from 30 cases of tuberculosis in six species of pinniped and seven related isolates were compared to representative and standard strains of the M. tuberculosis complex. The seal isolates could be distinguished from other members of the M. tuberculosis complex, including the recently defined 'Mycobacterium canettii' and 'Mycobacterium caprae', on the basis of host preference and phenotypic and genetic tests. Pinnipeds appear to be the natural host for this 'seal bacillus', although the organism is also pathogenic in guinea pigs, rabbits, humans, Brazilian tapir (Tapirus terrestris) and, possibly, cattle. Infection caused by the seal bacillus is predominantly associated with granulomatous lesions in the peripheral lymph nodes, lungs, pleura, spleen and peritoneum. Cases of disseminated disease have been found. As with other members of the M. tuberculosis complex, aerosols are the most likely route of transmission. The name Mycobacterium pinnipedii sp. nov. is proposed for this novel member of the M. tuberculosis complex (the type strain is 6482(T)=ATCC BAA-688(T)=NCTC 13288(T)).
Pourahmad, Fazel; Pate, Mateja; Ocepek, Matjaž; Borroni, Emanuele; Cabibbe, Andrea M; Capitolo, Eleonora; Cittaro, Davide; Frizzera, Eliana; Jenčič, Vlasta; Mariottini, Alessandro; Marumo, Kenji; Vaggelli, Guendalina; Cirillo, Daniela M; Tortoli, Enrico
The name 'Mycobacterium angelicum' dates back to 2003 when it was suggested for a slowly growing mycobacterium isolated from freshwater angelfish. This name is revived here and the novel species is proposed on the basis of the polyphasic characterization of four strains including the original one. The four strains presented 100 % 16S rRNA gene sequence similarity with Mycobacterium szulgai but clearly differed from M. szulgai for the milky white aspect of the colonies. The sequence similarity with the type strain of M. szulgai ranged, in eight additionally investigated genetic targets, from 78.9 to 94.3 %, an evident contrast with the close relatedness that emerged at the level of 16S rRNA gene. The average nucleotide identity between the genomes of M. szulgai DSM 44166T and strain 126/5/03T (type strain of the novel species) was 92.92 %, and supported the status of independent species. The confirmation of the name Mycobacterium angelicum sp. nov. is proposed, with strain 126/5/03T ( = CIP 109313T = DSM 45057T) as the type strain.
Adékambi, Toïdi; Stein, Andréas; Carvajal, Joseph; Raoult, Didier; Drancourt, Michel
A nonpigmented rapidly growing mycobacterium was isolated from wound liquid outflow, bone tissue biopsy, and excised skin tissue from a 31-year-old woman who suffered an accidental open right tibia fracture and prolonged stay in a river. The three isolates grew in 3 days at 24 to 37 degrees C. 16S rRNA sequence analyses over 1,483 bp showed that they were identical and shared 99.7% (4-bp difference) sequence similarity with that of Mycobacterium porcinum, the most closely related species. Partial rpoB (723 bp) sequence analyses showed that the isolates shared 97.0% sequence similarity with that of M. porcinum. Further polyphasic approaches, including biochemical tests, antimicrobial susceptibility analyses, and hsp65, sodA, and recA gene sequence analysis, as well as % G+C determination and cell wall fatty acid composition analysis supported the evidence that these isolates were representative of a new species. Phylogenetic analyses showed the close relationship with M. porcinum in the Mycobacterium fortuitum group. The isolates were susceptible to most antibiotics and exhibited evidence for penicillinase activity, in contrast to M. porcinum. We propose the name Mycobacterium conceptionense sp. nov. for this new species associated with posttraumatic osteitis. The type strain is D16(T) (equivalent to CIP 108544(T) and CCUG 50187(T)).
Adékambi, Toïdi; Stein, Andréas; Carvajal, Joseph; Raoult, Didier; Drancourt, Michel
A nonpigmented rapidly growing mycobacterium was isolated from wound liquid outflow, bone tissue biopsy, and excised skin tissue from a 31-year-old woman who suffered an accidental open right tibia fracture and prolonged stay in a river. The three isolates grew in 3 days at 24 to 37°C. 16S rRNA sequence analyses over 1,483 bp showed that they were identical and shared 99.7% (4-bp difference) sequence similarity with that of Mycobacterium porcinum, the most closely related species. Partial rpoB (723 bp) sequence analyses showed that the isolates shared 97.0% sequence similarity with that of M. porcinum. Further polyphasic approaches, including biochemical tests, antimicrobial susceptibility analyses, and hsp65, sodA, and recA gene sequence analysis, as well as % G+C determination and cell wall fatty acid composition analysis supported the evidence that these isolates were representative of a new species. Phylogenetic analyses showed the close relationship with M. porcinum in the Mycobacterium fortuitum group. The isolates were susceptible to most antibiotics and exhibited evidence for penicillinase activity, in contrast to M. porcinum. We propose the name Mycobacterium conceptionense sp. nov. for this new species associated with posttraumatic osteitis. The type strain is D16T (equivalent to CIP 108544T and CCUG 50187T). PMID:16597850
Gui, Jing; Wang, Feng; Hong, Chuang-yue; Li, Jin-li; Liang, Jing
To study the drug resistance profile of Mycobacterium(M.) chelonae and M.abscessus and to evaluate the clinical application of Etest(epsilometer test) for susceptibility testing. Twenty clinical isolates of M.abscessus and 16 clinical isolates of M.chelonae from clinical specimens were collected.Strain identification was carried out by GenoType Mycobacterium CM assay(Hain Lifescience, Germany). The accuracy was evaluated by comparing Etest results to those obtained by broth microdilution. Thirty-six isolates were tested against amikacin, cefoxitin, ciprofloxacin, clarithromycin, doxycycline, imipenem, linezolid, sulfamethoxazole and tobramycin. The agreement among MICs and interpretive category was evaluated. Chi-squared test was used to compare observed frequency of each of the 2 examples. All of the isolates(36/36) were sensitive to amikacin and cefoxitin, and only 1 isolate(1/36) was resistant to clarithromycin, but more isolates(29/36) were resistant to ciprofloxacin, doxycycline, imipenem and sulfamethoxazole.For M.chelonae, only 2/16 were resistant to linezolid, and 7/16 resistant to tobramycin.For M.abscessus, more than 12/20 were resistant to linezolid and 16/20 resistant to tobramycin. The agreement between broth microdilution MICs and Etest MICs for 9 drugs was 149/324.With amikacin, clarithromycin, doxycycline and imipenem, the agreement for interpretive category was excellent(35/36), followed by sulfamethoxazole(34/36), which corresponded to rarely very major error of 2/36.With ciprofloxacin and tobramycin, agreement for interpretive category was 31/36 and 26/36.With cefoxitin and linezolid, the agreement of Etest MICs was the lowest(14/36), resulting in the resistant category. Isolates of M.chelonae and M.abscessus exhibit far more susceptibility to amikacin, cefoxitin and clarithromycin than any other antimicrobial agents.Linezolid and tobramycin showed sensitivity to some isolates of M.chelonae.It is suitable for the Etest method as a simple reliable
Chang, Jennifer C. W; Sherman, David R
Granulomas are organized host immune structures composed of tightly interposed macrophages and other cells that form in response to a variety of persistent stimuli, both infectious and noninfectious. The tuberculous granuloma is essential for host containment of mycobacterial infection, although it does not always eradicate it. Therefore, it is considered a host-beneficial, if incompletely efficacious, immune response. The Mycobacterium RD1 locus encodes a specialized secretion system that promotes mycobacterial virulence by an unknown mechanism. Using transparent zebrafish embryos to monitor the infection process in real time, we found that RD1-deficient bacteria fail to elicit efficient granuloma formation despite their ability to grow inside of infected macrophages. We showed that macrophages infected with virulent mycobacteria produce an RD1-dependent signal that directs macrophages to aggregate into granulomas. This Mycobacterium-induced macrophage aggregation in turn is tightly linked to intercellular bacterial dissemination and increased bacterial numbers. Thus, mycobacteria co-opt host granulomas for their virulence. PMID:15510227
Akama, Takeshi; Tanigawa, Kazunari; Kawashima, Akira; Wu, Huhehasi; Ishii, Norihisa; Suzuki, Koichi
Mycobacterium leprae, the causative agent of leprosy, does not grow under in vitro condition, making molecular analysis of this bacterium difficult. For this reason, bacteriological information regarding M. leprae gene function is limited compared with other mycobacterium species. In this study, we performed DNA microarray analysis to clarify the RNA expression profile of the Thai53 strain of M. leprae grown in footpads of hypertensive nude rats (SHR/NCrj-rnu). Of 1605 M. leprae genes, 315 showed signal intensity twofold higher than the median. These genes include Acyl-CoA metabolic enzymes and drug metabolic enzymes, which might be related to the virulence of M. leprae. In addition, consecutive RNA expression profile and in silico analyses enabled identification of possible operons within the M. leprae genome. The present results will shed light on M. leprae gene function and further our understanding of the pathogenesis of leprosy.
Minnikin, David E; Kremer, Laurent; Dover, Lynn G; Besra, Gurdyal S
Mycobacterium tuberculosis continues to be the predominant global infectious agent, annually killing over three million people. Recommended drug regimens have the potential to control tuberculosis, but lack of adherence to such regimens has resulted in the emergence of resistant strains. Mycobacterium tuberculosis has an unusual cell envelope, rich in unique long-chain lipids, that provides a very hydrophobic barrier to antibiotic access. Such lipids, however, can be drug targets, as exemplified by the action of the front-line drug isoniazid on mycolic acid biosynthesis. A number of these lipids are potential key virulence factors and their structures are based on very characteristic methyl-branched long-chain acids and alcohols. This review details the history, structure, and genetic aspects of the biosynthesis of these methyl-branched components, good examples of which are the phthiocerols and the mycocerosic and mycolipenic acids.
Gorse, Diane; Dhinojwala, Ali; Moore, Francisco
Pulmonary tuberculosis (PTB) causes more than 1 million deaths annually. Smear microscopy is a primary rapid detection tool in areas where 95 % of PTB cases occur. This technique, in which the sputum of a symptomatic patient is stained and examined using a light microscope for Mycobacterium tuberculosis (MTB) shows sensitivity between 20 and 60 %. Insufficient bacterial isolation during sample preparation may be a reason for low sensitivity. We are optimizing a system to capture bacteria on the basis of electrostatic interactions to more thoroughly isolate bacteria from suspension and facilitate more accurate detection. Silica supports coated with positively-charged polyelectrolyte, poly(diallyldimethylammonium chloride), captured approximately 4.1 times more Mycobacterium smegmatis, a model organism for MTB, than was captured on negatively-charged silica substrates. Future experimentation will employ branched polymer systems and seek to justify the use of colloidal stability theories to describe initial capture. Supported by University of Akron, Department of Polymer Science, Department of Biology; LORD Corporation.
Cerda-Maira, Francisca A; McAllister, Fiona; Bode, Nadine J; Burns, Kristin E; Gygi, Steven P; Darwin, K Heran
Prokaryotic ubiquitin-like protein (Pup) is a post-translational modifier that attaches to more than 50 proteins in Mycobacteria. Proteasome accessory factor A (PafA) is responsible for Pup conjugation to substrates, but the manner in which proteins are selected for pupylation is unknown. To address this issue, we reconstituted the pupylation of model Mycobacterium proteasome substrates in Escherichia coli, which does not encode Pup or PafA. Surprisingly, Pup and PafA were sufficient to pupylate at least 51 E. coli proteins in addition to the mycobacterial proteins. These data suggest that pupylation signals are intrinsic to targeted proteins and might not require Mycobacterium-specific cofactors for substrate recognition by PafA in vivo. PMID:21738222
Mol, J P S; Carvalho, T F; Fonseca, A A; Sales, E B; Issa, M A; Rezende, L C; Hodon, M A; Tinoco, H P; Malta, M C C; Pessanha, A T; Pierezan, F; Mota, P M P C; Paixão, T A; Santos, R L
Tuberculosis, associated with Mycobacterium bovis, was diagnosed post mortem in an adult female capybara (Hydrochoerus hydrochaeris), kept at the Pampulha Ecological Park, Belo Horizonte, Brazil, in a large metropolitan area. On post-mortem examination, there were numerous firm white nodules scattered throughout all lobes of both lungs. Tissue samples were collected for histological and microbiological examination. Microscopically, the pulmonary nodules were multifocal to coalescing granulomas and intralesional acid-fast bacilli were evident in Ziehl-Neelsen-stained sections of the lung and spleen. Colonies with morphological features of Mycobacterium spp. were isolated from lung samples and conventional polymerase chain reaction (PCR) with genomic DNA from the isolates was positive for M. bovis; sequencing indicated 100% identity with the region of difference 4 (RD4) of M. bovis. In addition, M. bovis DNA was detected in the lung by quantitative PCR. The finding of M. bovis in a capybara indicates a potential public health risk in a zoological collection.
Donini, Stefano; Garavaglia, Silvia; Ferraris, Davide M.; Miggiano, Riccardo; Mori, Shigetarou; Shibayama, Keigo
Mycobacterium smegmatis represents one model for studying the biology of its pathogenic relative Mycobacterium tuberculosis. The structural characterization of a M. tuberculosis ortholog protein can serve as a valid tool for the development of molecules active against the M. tuberculosis target. In this context, we report the biochemical and structural characterization of M. smegmatis phosphoribosylpyrophosphate synthetase (PrsA), the ortholog of M. tuberculosis PrsA, the unique enzyme responsible for the synthesis of phosphoribosylpyrophosphate (PRPP). PRPP is a key metabolite involved in several biosynthetic pathways including those for histidine, tryptophan, nucleotides and decaprenylphosphoryl-arabinose, an essential precursor for the mycobacterial cell wall biosynthesis. Since M. tuberculosis PrsA has been validated as a drug target for the development of antitubercular agents, the data presented here will add to the knowledge of the mycobacterial enzyme and could contribute to the development of M. tuberculosis PrsA inhibitors of potential pharmacological interest. PMID:28419153
Nigou, J; Gilleron, M; Brando, T; Vercellone, A; Puzo, G
The structures of the hydrophilic parietal and cellular arabinomannans isolated from Mycobacterium bovis BCG cell wall [Nigou et al. (1997) J Biol Chem 272: 23094-103] were investigated. Their molecular mass as determined by MALDI-TOF mass spectrometry was around 16 kDa. Concerning cap structure, capillary electrophoresis analysis demonstrated that dimannoside (Manpalpha1-->2Manp) was the most abundant motif (65-75%). Using two-dimensional 1H-13C NMR spectroscopy, the mannan core was unambiguously demonstrated to be composed of -->6Manpalpha1--> backbone substituted at some O-2 by a single Manp unit. The branching degree was determined as 84%. Finally, arabinomannans were found to be devoid of the phosphatidyl-myo-inositol anchor and, by aminonaphthalene disulfonate tagging, the mannan core was shown to contain a reducing end. This constitutes the main difference between arabinomannans and lipoarabinomannans from Mycobacterium bovis BCG.
Mycobacterium marinum is a waterborne mycobacterium that commonly infects fish and amphibians worldwide. Infection in humans occurs occasionally, in most cases as a granulomatous infection localized in the skin, typically following minor trauma on the hands. For this reason, infection is especially common among aquarium keepers. Such local infection may-though infrequently-spread to tendon sheaths or joints. Disseminated disease, which is rare, can occur in immunosuppressed patients. In order to obtain a definitive diagnosis, culture and histopathological examination of biopsies from skin or other tissues are recommended. Infections sometimes heal spontaneously, but drug treatment is usually necessary for several months in order to cure the infection. Doxycycline or clarithromycin is used most commonly, although in severe cases, a combination of rifampicin and ethambutol is recommended.
Tigges, Frauke; Bauer, Andrea; Hochauf, Kristina; Meurer, Michael
A case of a sporotrichoid cutaneous infection caused by Mycobacterium marinum is reported. A 53- year-old male patient presented with red, partly purulent nodular lesions on the back of his left hand, forearm, and upper medial arm that had developed consecutively during the past 4 weeks. A mycobacterial infection with M. marinum was confirmed by molecular methods in a lesional skin biopsy. The patient was treated systemically with rifampicin (750 mg/day) and clarithromycine (1,000 mg/day), and topically with sulmycin (gentamicin sulfate). After 12 weeks of treatment the nodules regressed, leaving behind erythematous patches. M. marinum is a waterborne mycobacterium that commonly infects fish and amphibians worldwide. Transmissions to humans occur occasionally, in most cases as a granulomatous infection localized to the skin, typically following minor trauma to the hands. For this reason, infections are especially common among aquarium keepers.
Trojanowski, Damian; Ginda, Katarzyna; Pióro, Monika; Hołówka, Joanna; Skut, Partycja; Jakimowicz, Dagmara
ABSTRACT It has recently been demonstrated that bacterial chromosomes are highly organized, with specific positioning of the replication initiation region. Moreover, the positioning of the replication machinery (replisome) has been shown to be variable and dependent on species-specific cell cycle features. Here, we analyzed replisome positions in Mycobacterium smegmatis, a slow-growing bacterium that exhibits characteristic asymmetric polar cell extension. Time-lapse fluorescence microscopy analyses revealed that the replisome is slightly off-center in mycobacterial cells, a feature that is likely correlated with the asymmetric growth of Mycobacterium cell poles. Estimates of the timing of chromosome replication in relation to the cell cycle, as well as cell division and chromosome segregation events, revealed that chromosomal origin-of-replication (oriC) regions segregate soon after the start of replication. Moreover, our data demonstrate that organization of the chromosome by ParB determines the replisome choreography. PMID:25691599
The incidence of Buruli ulcer, caused by Mycobacterium ulcerans, has been increasingly rapidly over the past thirty years, particularly in Africa. These extensive necrotic lesions are due to mycolactone, a toxin produced by the bacterium. The mode of Mycobacterium ulcerans transmission is still controversial, and several insect species have been incriminated. Several infected mosquito species have been identified in Australia, while predatory water bugs, particularly belostomatids and naucorids, have been implicated in Africa. Indeed, the bacterium has been detected in these insects' salivary glands, and experimental transmission to mice has been demonstrated, raising the possibility of human transmission by water bug bites. Interestingly, individuals highly exposed to water bug bites tend to be less often infected, indicating that frequent bites by non infected bugs might have a protective effect. Insect-borne transmission would be a minor route of transmission compared to direct transmission via skin trauma.
Olalla, J; Pombo, M; Aguado, J M; Rodríguez, E; Palenque, E; Costa, J R; Riopérez, E
Endocarditis due to Mycobacterium fortuitum complex is a rare entity generally linked to the hospital environment. Only 18 cases have been published since 1966. Here we present a case of a female who developed an endocarditis due to Mycobacterium chelonae after valve replacement as well as a review of the literature. The course of this kind of endocarditis is generally subacute and the outcome is usually fatal. Blood cultures were positive in 75% of cases of metallic valve endocarditis, versus 20% in bioprostheses. The treatment must include antibiotics that have shown activity against these mycobacteria, such as amikacin, imipenem, cefoxitin, fluorinated quinolones and macrolides (especially clarithromycin). Surgical removal is recommended. Although the prognosis for the patient is poor, we should expect better outcomes with the use of new antibiotic regimens.
Menendez, M. C.; Palenque, E.; Navarro, M. C.; Nuñez, M. C.; Rebollo, M. J.; Garcia, M. J.
This paper describes a Mycobacterium intracellulare variant strain causing an unusual infection. Several isolates obtained from an immunocompromised patient were identified as members of the Mycobacterium avium complex (MAC) by the commercial AccuProbe system and biochemical standard identification. Further molecular approaches were undertaken for a more accurate characterization of the bacteria. Up to seven different genomic sequences were analyzed, ranging from conserved mycobacterial genes such as 16S ribosomal DNA to MAC-specific genes such as mig (macrophage-induced gene). The results obtained identify the isolates as a variant of M. intracellulare, an example of the internal variability described for members of the MAC, particularly within that species. The application of other molecular approaches is recommended for more accurate identification of bacteria described as MAC members. PMID:11724827
Menendez, M C; Palenque, E; Navarro, M C; Nuñez, M C; Rebollo, M J; Garcia, M J
This paper describes a Mycobacterium intracellulare variant strain causing an unusual infection. Several isolates obtained from an immunocompromised patient were identified as members of the Mycobacterium avium complex (MAC) by the commercial AccuProbe system and biochemical standard identification. Further molecular approaches were undertaken for a more accurate characterization of the bacteria. Up to seven different genomic sequences were analyzed, ranging from conserved mycobacterial genes such as 16S ribosomal DNA to MAC-specific genes such as mig (macrophage-induced gene). The results obtained identify the isolates as a variant of M. intracellulare, an example of the internal variability described for members of the MAC, particularly within that species. The application of other molecular approaches is recommended for more accurate identification of bacteria described as MAC members.
Fabbian, Fabio; De Giorgi, Alfredo; Pala, M; Fratti, Daniela; Contini, Carlo
Mycobacterium fortuitum is a non-tuberculous mycobacterium that can cause pneumonia, abscess and empyema in subjects with predisposing lung diseases. However, pleurisy with effusion is rare. Herein, we report the case of a 74-year-old immunocompetent female patient without apparent risk factors, who suffered haemorrhagic pleural effusion as the main clinical manifestation. Pleural nodules were detected by computed tomography scan, and microbiological analysis revealed M. fortuitum in the absence of other pathogens. The patient was treated with ceftriaxone and ciprofloxacin, and full recovery ensued in 4 weeks. To our knowledge, this is the first reported case of haemorrhagic pleural effusion in an immunocompetent patient without underlying diseases. Although non-tuberculous mycobacterial infections are rarely accompanied by pleural involvement, M. fortuitum should be considered in such cases, especially when microbiology fails to detect the usual pathogens, and when the clinical picture is unclear.
Sparks, Rebecca; Khatami, Ameneh
Mycobacterium fortuitum complex skin infection is described in a previously healthy adolescent girl in Sydney, Australia. Mycobacterium fortuitum typically causes superficial skin infections following trauma to the skin and in our patient may have been related to prior leg "waxing". This case highlights common causes for a delay in diagnosis: lack of clinician awareness and inadequate microbiological and histopathological investigations of tissue samples. Due to the size and number of lesions, surgical excision was felt to be a less desirable therapeutic option due to the potential risk of poor cosmetic outcome for our patient. The standard chemotherapeutic approach to M. fortuitum infections involves the use of a combination of at least two antimicrobial agents to which the isolate is susceptible. Despite in vitro susceptibility testing that suggested that the isolate from our patient was resistant to most oral anti-microbial agents, our patient was treated successfully with a 10-week course of oral trimethoprim-sulfamethoxazole and moxifloxacin.
Delafont, Vincent; Samba-Louaka, Ascel; Cambau, Emmanuelle; Bouchon, Didier; Moulin, Laurent; Héchard, Yann
Nontuberculous mycobacteria (NTM) are environmental bacteria increasingly associated to public health problems. In water systems, free-living amoebae (FLA) feed on bacteria by phagocytosis, but several bacteria, including many NTM, are resistant to this predation. Thus, FLA can be seen as a training ground for pathogenic bacteria. Mycobacterium llatzerense was previously described as frequently associated with FLA in a drinking water network. The present study aimed to characterize the interactions between M. llatzerense and FLA. M. llatzerense was internalised by phagocytosis and featured lipid inclusions, suggesting a subversion of host resources. Moreover, M. llatzerense survived and even multiplied in presence of A. castellanii. Using a genomic-based comparative approach, twelve genes involved in phagocytosis interference, described in M. tuberculosis, were identified in the M. llatzerense genome sequenced in this study. Transcriptomic analyses showed that ten genes were significantly upregulated during the first hours of the infection, which could partly explain M. llatzerense resistance. Additionally, M. llatzerense was shown to actively inhibit phagosome acidification. In conclusion, M. llatzerense presents a high degree of resistance to phagocytosis, likely explaining its frequent occurrence within FLA in drinking water networks. It underscores that NTM should be carefully monitored in water networks to prevent human health concerns. PMID:28393860
Hamid, Mohamed E.
Mycobacterium farcinogenes and M. senegalense are the causal agents of bovine farcy, a chronic, progressive disease of the skin and lymphatics of zebu cattle. The disease, which is prevalent mainly in sub-Saharan Africa, was in earlier times thought to be caused by Nocardia farcinica and can be described as one of the neglected diseases in cattle. Some aspects of the disease have been investigated during the last five decades but the major development had been in the bacteriological, chemotaxonomic, and phylogenetic aspects. Molecular analyses confirmed that M. farcinogenes and M. senegalense fall in a subclade together with M. houstonense and M. fortuitum. This subclade is closely related to the one accommodating M. peregrinum, M. porcinum, M. septicum, M. neworleansense, and M. alvei. DNA probes were designed from 16S-23S rRNA internal transcribed spacer and could be used for the rapid diagnosis of bovine farcy. An ELISA assay has been evaluated for the serodiagnosis of the disease. The zoonotic potentials of M. farcinogenes and M. senegalense are unknown; few studies reported the isolation of M. senegalense and M. farcinogenes from human clinical sources but not from environmental sources or from other domestic or wild animals. PMID:24876989
Wayne, L G; Diaz, G A
A novel class of catalase, which differs from the previously described M- and T-catalases of mycobacteria, was detected in strains of Mycobacterium avium and M. intracellulare. Designated A-catalase, this enzyme resisted inactivation at 68 degrees C, was inactivated by 3-amino-1,2,4-triazole (aminotriazole), and exhibited no peroxidase activity. All of these properties distinguished the enzyme from T-catalase. The A-catalase exhibited a Km of 70 mM H2O2, which is between the upper and lower extremes of the ranges reported for T- and M-catalases, respectively. The A-catalase appeared to be more hydrophobic than M-catalase and did not react with antiserum to a representative sample of this class. The banding patterns of T- and M-catalases seen by polyacrylamide gel electrophoresis (PAGE) were essentially unaffected by the incorporation of sodium dodecyl sulfate (SDS) into the PAGE system, whereas the single band of A-catalase seen by PAGE without SDS resolved into as many as five bands in the presence of SDS; these bands were all of slower mobility than the original band. The banding pattern seen with SDS appeared to be related more to counterion charge effects than to molecular size increases that could be attributed to SDS complexed to the protein. It remains to be determined whether the multiple A-catalase bands reflect different proteins or different SDS micellar complexes of a single protein. Images PMID:3346077
Wallace, R J; Meier, A; Brown, B A; Zhang, Y; Sander, P; Onyi, G O; Böttger, E C
Resistance to clarithromycin among isolates of Mycobacterium chelonae and M. abscessus was observed in 18 of 800 (2.3%) patients tested between 1990 and 1995. Patients whose isolates were resistant had either disseminated disease or chronic lung disease, and the resistant isolates were recovered after clarithromycin monotherapy. Sequencing of the gene coding for the 23S rRNA peptidyltransferase region revealed a point mutation involving adenine at position 2058 (38%) or adenine at position 2059 (62%) in 20 of 20 relapse isolates from the first 13 patients identified. By pulsed-field gel electrophoresis or random amplified polymorphic DNA PCR, initial and relapse isolates were shown to have identical DNA patterns. M. chelonae and M. abscessus isolates were found to have only a single chromosomal copy of the rRNA operon, thus making them susceptible to single-step mutations. Thus, clarithromycin resistance in these species of rapidly growing mycobacteria relates to a point mutation in the gene coding for 23S rRNA and occurs in limited clinical situations, but was identified in almost 5% of isolates tested in 1995. PMID:8807061
Sha, Shanshan; Shi, Xiaoxia; Deng, Guoying; Chen, Lina; Xin, Yi; Ma, Yufang
Mycobacterium tuberculosis can interfere with host immune response and escape clearance through its specific antigens. M. tuberculosis Rv1987 encoded by region of difference (RD)-2 gene is a secretory protein with immunogenic potency. Here, we investigated the impact of Rv1987 on host cytokine responses and T cell polarization in mouse aerosol model. A recombinant M. smegmatis mc(2)155 strain that overexpressed Rv1987 protein (named MS1987) was constructed and used to infect C57BL/6 mice. The mc(2)155 harbored the empty vector (named MSVec) was as a control. The results showed that MS1987 challenged mice promoted Th2-biased cytokine responses with lower secretion of IFN-γ but higher production of IL-4 and Rv1987-specific IgG antibody compared to MSVec infected mice. Neutrophilic inflammation and high bacterial burden were observed in the lung tissues of MS1987 infected mice probably own to the failed Th1 cell immunity. Besides, subcutaneous injection of Rv1987 protein could mediate the Th1 cytokine responses caused by M. bovis BCG in mice. These results indicated that M. tuberculosis Rv1987 protein could modulate host immune response towards Th2 profile, which probably contributed to the immune evasion of bacteria from host elimination. Copyright © 2017 Elsevier GmbH. All rights reserved.
Höner Zu Bentrup, K; Miczak, A; Swenson, D L; Russell, D G
Analysis by two-dimensional gel electrophoresis revealed that Mycobacterium avium expresses several proteins unique to an intracellular infection. One abundant protein with an apparent molecular mass of 50 kDa was isolated, and the N-terminal sequence was determined. It matches a sequence in the M. tuberculosis database (Sanger) with similarity to the enzyme isocitrate lyase of both Corynebacterium glutamicum and Rhodococcus fascians. Only marginal similarity was observed between this open reading frame (ORF) (termed icl) and a second distinct ORF (named aceA) which exhibits a low similarity to other isocitrate lyases. Both ORFs can be found as distinct genes in the various mycobacterial databases recently published. Isocitrate lyase is a key enzyme in the glyoxylate cycle and is essential as an anapleurotic enzyme for growth on acetate and certain fatty acids as carbon source. In this study we express and purify Icl, as well as AceA proteins, and show that both exhibit isocitrate lyase activity. Various known inhibitors for isocitrate lyase were effective. Furthermore, we present evidence that in both M. avium and M. tuberculosis the production and activity of the isocitrate lyase is enhanced under minimal growth conditions when supplemented with acetate or palmitate.
Song, Houhui; Niederweis, Michael
Knowledge of the metabolic pathways used by Mycobacterium tuberculosis during infection is important for understanding its nutrient requirements and host adaptation. However, uptake, the first step in the utilization of nutrients, is poorly understood for many essential nutrients, such as inorganic anions. Here, we show that M. tuberculosis utilizes nitrate as the sole nitrogen source, albeit at lower efficiency than asparagine, glutamate, and arginine. The growth of the porin triple mutant M. smegmatis ML16 in media with limiting amounts of nitrate and sulfate as sole nitrogen and sulfur sources, respectively, was delayed compared to that of the wild-type strain. The uptake of sulfate was 40-fold slower than that of the wild-type strain, indicating that the efficient uptake of these anions is dependent on porins. The uptake by M. tuberculosis of sulfate and phosphate was approximately 40- and 10-fold slower than that of M. smegmatis, respectively, which is consistent with the slower growth of M. tuberculosis. However, the uptake of these anions by M. tuberculosis is orders of magnitude faster than diffusion through lipid membranes, indicating that unknown outer membrane proteins are required to facilitate this process.
Walters, S B; Hanna, B A
We tested isolates of Mycobacterium tuberculosis recovered from 117 patients for their susceptibilities to isoniazid (INH) and rifampin (RIF) by the Centers for Disease Control and Prevention's disk modification of the indirect method of proportions (MOP) test and a three-tube mycobacteria growth indicator tube (MGIT; BBL) antimycobacterial susceptibility test (AST). Sixty-seven of the M. tuberculosis isolates were recovered from Lowenstein-Jensen (BBL) subcultures, and 50 of the isolates were recovered from MGIT cultures of samples from various body sites. For the MGIT AST method, 0.5 ml of test organism suspension was inoculated into an MGIT with 0.1 micrograms of INH per ml, an MGIT with 1.0 micrograms of RIF per ml, and growth control MGIT. The tubes were incubated at 37 degrees C and were examined daily. The MGIT AST results were interpreted as follows: susceptible if the tubes containing INH or RIF did not fluoresce within 2 days of the time that the positive growth control fluoresced and resistant if the tubes containing INH or RIF did fluoresce within 2 days of the time that the positive growth control fluoresced. The mean time fluorescence for the positive growth control was 5.5 days. The two methods were in agreement for 114 of the 117 isolates from patients, while for 3 isolates there were minor discordant results. PMID:8735121
Jayawardana, Kalana W.; Jayawardena, H. Surangi N.; Wijesundera, Samurdhi A.; De Zoysa, Thareendra; Sundhoro, Madanodaya
Silica and iron oxide nanoparticles with sizes ranging from 6 to 40 nm were functionalized with trehalose. The trehalose-conjugated nanoparticles showed strong interactions with Mycobacterium smegmatis (M. smegmatis) and minimal interactions with macrophage (RAW 264.7) or A549 cells. In addition, trehalose-conjugated silica nanoparticles selectively interacted with M. smegmatis on M. smegmatis-treated A549 cells, demonstrating high potential of trehalose in developing targeted therapy for treating mycobacterial infection. PMID:26121049
Cadena, Gilbert; Wiedeman, Jean; Boggan, James E
Postsurgical infection is one of the greatest potential morbidities of ventriculoperitoneal shunt surgery. The majority of infections can be linked to contamination with skin flora at the time of surgery, a phenomenon that has been well described. However, there is a paucity of literature regarding infection with nontuberculous mycobacteria. The authors report a case of postoperative ventriculoperitoneal shunt infection with Mycobacterium fortuitum and review the available neurosurgical literature and treatment strategies.
Achermann, Yvonne; Rössle, Matthias; Hoffmann, Matthias; Deggim, Vanessa; Kuster, Stefan; Zimmermann, Dieter R; Bloemberg, Guido; Hombach, Michael; Hasse, Barbara
Prosthetic valve endocarditis (PVE) due to fast-growing nontuberculous mycobacteria (NTM) has been reported anecdotally. Reports of PVE with slowly growing NTM, however, are lacking. We present here one case of PVE and one case of bloodstream infection caused by Mycobacterium chimaera. Randomly amplified polymorphic DNA (RAPD)-PCR indicated a relatedness of the two M. chimaera strains. Both patients had heart surgery 2 years apart from each other. A nosocomial link was not detected.
Hasan, Nabeeh A; Honda, Jennifer R; Davidson, Rebecca M; Epperson, L Elaine; Bankowski, Matthew J; Chan, Edward D; Strong, Michael
Mycobacterium chimaera is a nontuberculous mycobacterial species that causes cardiovascular, pulmonary, and postsurgical infections. Here, we report the first complete genome sequence of M. chimaera This genome is 6.33 Mbp, with a G+C content of 67.56%, and encodes 4,926 protein-coding genes, as well as 74 tRNAs, one ncRNA, and three rRNA genes. Copyright © 2016 Hasan et al.
Wongkitisophon, Pranee; Rattanakaemakorn, Ploysyne; Tanrattanakorn, Somsak; Vachiramon, Vasanop
Non-tuberculous mycobacterial skin infections have an increasing incidence. In immunocompetent patients, they usually follow local trauma. We present a case of cutaneous Mycobacterium abscessus infection following mesotherapy. The lesions were successfully treated with a combination of clarithromycin, ciprofloxacin, and doxycycline. Atypical mycobacterial infection should be suspected in patients who develop late-onset skin and soft tissue infection after cutaneous injury, injection, and surgical intervention, particularly if they do not respond to conventional antibiotic treatment. PMID:21487459
Cummings, D M; Ristroph, D; Camargo, E E; Larson, S M; Wagner, H N
A radiometric test capable of detecting the metabolic rate of M. tuberculosis within 18 hr after inoculation has been developed. The technique is based on the measurement of 14CO2 produced by the bacterial metabolism of 14C-U-glycerol of 14C-U-acetate. The test is an important first step in the development of rapid radiometric techniques for clinical study of Mycobacterium tuberculosis.
Sinha, Raj; Tuckett, John; Hide, Geoff; Dildey, Petra; Karsandas, Alvin
Septic subacromial bursitis is an uncommon disorder with only a few reported cases in the literature. The most common causative organism is Staphylococcus aureus. We report the case of a 61-year-old female with a septic subacromial bursitis where the causative organism was found to be Mycobacterium avium-intracellulare (MAI). The diagnosis was only made following a biopsy, and we use this case to highlight the importance of recognising the need to consider a biopsy and aspiration in atypical situations.
Majoor, C; Schreurs, A; Weers-Pothoff, G
A 48 year old patient with active Crohn's disease presented with bilateral nodules over his lungs resembling malignant metastasis. Bronchoscopic and pathological examination of the airways and sputum did not show any malignancy. After 6 weeks Mycobacterium xenopi was cultured from his bronchial washings while all other cultures remained negative. Treatment was started with rifampicin, ethambutol, and clarithromycin and, after 9 months of treatment, there was an almost complete resolution of his chest radiograph. PMID:15223876
Cennimo, David J.; Agag, Richard; Fleegler, Earl; Lardizabal, Alfred; Klein, Kenneth M.; Wenokor, Cornelia; Swaminathan, Shobha
Objective: We present the case of a sushi chef with pain and swelling of his index finger and wrist for a year, unresponsive to antibiotics. Methods: Biopsy showed a xanthogranulomatous reaction and positive culture results for Mycobacterium marinum. Results: He was treated with minocycline, clarithromycin, and ethambutol. In addition, he underwent radical synovectomy of the lesion. Conclusion: The combined medical and surgical approach resulted in a positive outcome. PMID:19915656
Roffe, Thomas J.
An unusual gross appearance of avian tuberculosis, where fluid-filled thin-walled cysts are produced and grossly apparent in preference to granulomas, is presented. Histopathology confirmed the granulomatous nature of the lesions and the presence of intracellular acid-fast organisms. Mycobacterium avium complex was cultured from affected organs. The unusual gross presentation in these cases indicates the need to consider tuberculosis in the differential of cystic diseases of avian livers.
Kato-Maeda, Midori; Metcalfe, John Z.; Flores, Laura
Genotyping is used to track specific isolates of Mycobacterium tuberculosis in a community. It has been successfully used in epidemiologic research (termed ‘molecular epidemiology’) to study the transmission dynamics of TB. In this article, we review the genetic markers used in molecular epidemiologic studies including the use of whole-genome sequencing technology. We also review the public health application of molecular epidemiologic tools. PMID:21366420
Falkinham, Joseph O; Iseman, Michael D; de Haas, Petra; van Soolingen, Dick
Mycobacterium avium was isolated from hot and cold water samples and from sediment (biofilm) collected from the showerhead in the home of a woman with M. avium pulmonary disease lacking known M. avium risk factors. IS1245/IS1311 DNA fingerprinting demonstrated that M. avium isolates from the hot and cold water and showerhead sediment demonstrated a clonal relationship with the patient's M. avium isolate. The data provide evidence that showers may serve as sources of infection by waterborne M. avium.
Samanovic, Marie I.; Darwin, K. Heran
The proteasome system of Mycobacterium tuberculosis is required for causing disease. Proteasomes are multi-subunit chambered proteases and, until recently, were only known to participate in adenosine triphosphate (ATP)-dependent proteolysis in bacteria. In this review, we discuss the latest advances in understanding how both ATP-dependent and ATP-independent proteasome-regulated pathways contribute to M. tuberculosis virulence. PMID:26526503
Pezzone, Natalia; Eberhardt, Ayelen T; Fernández, Analia; Garbaccio, Sergio; Zumárraga, Martín; Gioffré, Andrea; Magni, Carolina; Beldomenico, Pablo M; Marini, M Rocío; Canal, Ana M
This report describes the first case of Mycobacterium intracellulare infection with typical granulomatous lesions of mycobacteriosis in a capybara (Hydrochoerus hydrochaeris). The individual was a captive-bred young female, part of the control group of an experimental study on stress. Multiple granulomatous lesions were detected in a mesenteric lymph node of this young female. Mycobacterial infection was confirmed by bacteriologic culture and molecular identification methods. Clinical lesions were characterized by histopathology.
Fleischacker, Christine L; Segura-Totten, Miriam; Garlena, Rebecca A; Jacobs-Sera, Deborah; Pope, Welkin H; Russell, Daniel A; Hatfull, Graham F
Mycobacteriophage CrystalP is a newly isolated phage infecting Mycobacterium smegmatis strain mc(2)155. CrystalP has a 76,483-bp genome and is predicted to contain 143 protein-coding and 2 tRNA genes, including repressor and integrase genes consistent with a temperate lifestyle. CrystalP is related to the mycobacteriophages Toto and Kostya and to other Cluster E phages. Copyright © 2017 Fleischacker et al.
Vijay, Srinivasan; Nagaraja, Mukkayyan; Sebastian, Jees; Ajitkumar, Parthasarathi
Recently, several reports showed that about 80 % of mid-log phase Mycobacterium smegmatis, Mycobacterium marinum, and Mycobacterium bovis BCG cells divide symmetrically with 5-10 % deviation in the septum position from the median. However, the mode of cell division of the pathogenic mycobacterial species, Mycobacterium tuberculosis, remained unclear. Therefore, in the present study, using electron microscopy, fluorescence microscopy of septum- and nucleoid-stained live and fixed cells, and live cell time-lapse imaging, we show the occurrence of asymmetric cell division with unusually deviated septum/constriction in 20 % of the 15 % septating M. tuberculosis cells in the mid-log phase population. The remaining 80 % of the 15 % septating cells divided symmetrically but with 2-5 % deviation in the septum/constriction position, as reported for M. smegmatis, M. marinum, and M. bovis BCG cells. Both the long and the short portions of the asymmetrically dividing M. tuberculosis cells with unusually deviated septum contained nucleoids, thereby generating viable short and long cells from each asymmetric division. M. tuberculosis short cells were acid fast positive and, like the long cells, further readily underwent growth and division to generate micro-colony, thereby showing that they were neither mini cells, spores nor dormant forms of mycobacteria. The freshly diagnosed pulmonary tuberculosis patients' sputum samples, which are known for the prevalence of oxidative stress conditions, also contained short cells at the same proportion as that in the mid-log phase population. The probable physiological significance of the generation of the short cells through unusually deviated asymmetric cell division is discussed.
Gupta, Shashank; Cohen, Keira A; Winglee, Kathryn; Maiga, Mamoudou; Diarra, Bassirou; Bishai, William R
Drug efflux is an important resistance mechanism in Mycobacterium tuberculosis. We found that verapamil, an efflux inhibitor, profoundly decreases the MIC of bedaquiline and clofazimine to M. tuberculosis by 8- to 16-fold. This exquisite susceptibility was noted among drug-susceptible and drug-resistant clinical isolates. Thus, efflux inhibition is an important sensitizer of bedaquiline and clofazimine, and efflux may emerge as a resistance mechanism to these drugs.
Rubio, Marc; March, Francesca; Garrigó, Montserrat; Moreno, Carmen; Español, Montserrat; Coll, Pere
Purpose Clarithromycin was considered the cornerstone for the treatment of Mycobacterium abscessus complex infections. Genetic resistance mechanisms have been described and many experts propose amikacin as an alternative. Nevertheless, clarithromycin has several advantages; therefore, it is necessary to identify the non-functional erm(41) allele to determine the most suitable treatment. The aims of this study were to characterize the molecular mechanisms of clarithromycin resistance in a collection of Mycobacterium abscessus complex isolates and to verify the relationship between these mechanisms and the antibiogram. Materials and Methods Clinical isolates of M. abscessus complex (n = 22) from 16 patients were identified using four housekeeping genes (rpoB, secA1, sodA and hsp65), and their genetic resistance was characterized by studying erm(41) and rrl genes. Nine strains were recovered from the clinical isolates and subjected to E-test and microdilution clarithromycin susceptibility tests, with readings at 3, 7 and 14 days. Results We classified 11/16 (68.8%) M. abscessus subsp. abscessus, 4/16 (25.0%) M. abscessus subsp. bolletii, and 1/16 (6.3%) M. abscessus subsp. massiliense. T28 erm(41) allele was observed in 8 Mycobacterium abscessus subps. abscessus and 3 Mycobacterium abscessus subsp. bolletii. One strain of M. abscessus subsp. bolletii had an erm(41) gene truncated and was susceptible to clarithromycin. No mutations were observed in rrl gene first isolates. In three patients, follow-up of initial rrl wild-type strains showed acquired resistance. Conclusions Most clinical isolates of M. abscessus complex had inducible resistance to clarithromycin and total absence of constitutive resistance. Our findings showed that the acquisition of resistance mutations in rrl gene was associated with functional and non-functional erm(41) gene. Caution is needed when using erm(41) sequencing alone to identify M. abscessus subspecies. This study reports an acquired
Achermann, Yvonne; Rössle, Matthias; Hoffmann, Matthias; Deggim, Vanessa; Kuster, Stefan; Zimmermann, Dieter R.; Hombach, Michael; Hasse, Barbara
Prosthetic valve endocarditis (PVE) due to fast-growing nontuberculous mycobacteria (NTM) has been reported anecdotally. Reports of PVE with slowly growing NTM, however, are lacking. We present here one case of PVE and one case of bloodstream infection caused by Mycobacterium chimaera. Randomly amplified polymorphic DNA (RAPD)-PCR indicated a relatedness of the two M. chimaera strains. Both patients had heart surgery 2 years apart from each other. A nosocomial link was not detected. PMID:23536407
Clarke, Elsburgh O; Dorn, Brian; Boone, Allison; Risatti, Guillermo; Gilbert-Marcheterre, Kelly; Harms, Craig A
An adult yellow stingray (Urobatis jamaicensis) from a touch-tank exhibit developed a large abscess on the dorsal aspect of the calvarium and swollen soft tissue surrounding the left spiracle. A large amount of fluid exudate was drained from the abscess. Mycobacterium chelonae was diagnosed by cytology of the exudate and by polymerase chain reaction and sequencing. The animal was euthanized and disseminated mycobacteriosis was confirmed with histology.
Byrne, S K; Crawford, C E; Geddes, G L; Black, W A
After preliminary in vitro screening of 10 antimicrobial agents against Mycobacterium tuberculosis, the MICs of the 6 most promising agents against 27 clinical isolates were determined by agar dilution. The two quinolone compounds tested (difloxacin and A-56620) were the most active, each inhibiting 50% of the strains at concentrations of 4 micrograms/ml. M. tuberculosis strains previously shown to be resistant to isoniazid, streptomycin, rifampin, or ethambutol were as susceptible to these quinolone compounds as susceptible strains. PMID:3143305
Honda, Jennifer R.; Davidson, Rebecca M.; Epperson, L. Elaine; Bankowski, Matthew J.; Chan, Edward D.; Strong, Michael
Mycobacterium chimaera is a nontuberculous mycobacterial species that causes cardiovascular, pulmonary, and postsurgical infections. Here, we report the first complete genome sequence of M. chimaera. This genome is 6.33 Mbp, with a G+C content of 67.56%, and encodes 4,926 protein-coding genes, as well as 74 tRNAs, one ncRNA, and three rRNA genes. PMID:27881537
Ghodbane, Ramzi; Raoult, Didier; Drancourt, Michel
Mycobacterium tuberculosis culture, a critical technique for routine diagnosis of tuberculosis, takes more than two weeks. Here, step-by-step improvements in the protocol including a new medium, microaerophlic atmosphere or ascorbic-acid supplement and autofluorescence detection dramatically shortened this delay. In the best case, primary culture and rifampicin susceptibility testing were achieved in 72 hours when specimens were inoculated directly on the medium supplemented by antibiotic at the beginning of the culture.
Parandhaman, Dinesh Kumar; Narayanan, Sujatha
Cell death or senescence is a fundamental event that helps maintain cellular homeostasis, shapes the growth of organism, and provides protective immunity against invading pathogens. Decreased or increased cell death is detrimental both in infectious and non-infectious diseases. Cell death is executed both by regulated enzymic reactions and non-enzymic sudden collapse. In this brief review we have tried to summarize various cell death modalities and their impact on the pathogenesis of Mycobacterium tuberculosis. PMID:24634891
Baghban, Adam; Azar, Marwan Mikheal; Bernardo, Raffaele Mario; Malinis, Maricar
Mycobacterium tuberculosis presents unique challenges in the peritransplant period. Here, we describe a case of disseminated tuberculosis following renal transplantation with alemtuzumab induction immunosuppression in a patient with remotely treated pulmonary tuberculosis and ongoing risk factors for re-infection. We also review the available literature regarding the prevalence of tuberculosis infection following solid organ transplant and management of high-risk patients, including the role for isoniazid preventative therapy. 2016 BMJ Publishing Group Ltd.
Parandhaman, Dinesh Kumar; Narayanan, Sujatha
Cell death or senescence is a fundamental event that helps maintain cellular homeostasis, shapes the growth of organism, and provides protective immunity against invading pathogens. Decreased or increased cell death is detrimental both in infectious and non-infectious diseases. Cell death is executed both by regulated enzymic reactions and non-enzymic sudden collapse. In this brief review we have tried to summarize various cell death modalities and their impact on the pathogenesis of Mycobacterium tuberculosis.
Samanovic, Marie I; Darwin, K Heran
The proteasome system of Mycobacterium tuberculosis is required for causing disease. Proteasomes are multisubunit chambered proteases and, until recently, were only known to participate in adenosine triphosphate (ATP)-dependent proteolysis in bacteria. In this review, we discuss the latest advances in understanding how both ATP-dependent and ATP-independent proteasome-regulated pathways contribute to M. tuberculosis virulence. Copyright © 2015 Elsevier Ltd. All rights reserved.
Activity of rifapentine and its metabolite 25-O-desacetylrifapentine compared with rifampicin and rifabutin against Mycobacterium tuberculosis, Mycobacterium africanum, Mycobacterium bovis and M. bovis BCG.
Rastogi, N; Goh, K S; Berchel, M; Bryskier, A
The in vitro activity of rifapentine and its metabolite, 25-O:-desacetylrifapentine, as compared with that of rifampicin and rifabutin, was determined against Mycobacterium tuberculosis, Mycobacterium africanum, Mycobacterium bovis and M. bovis BCG. MICs were determined radiometrically and by the 1% proportional method using Middlebrook 7H11 agar. The bactericidal effect of the drugs was determined in parallel at selected concentrations. For drugsusceptible isolates of M. tuberculosis, the Bactec MICs of rifapentine and 25-O:-desacetylrifapentine were 0.03-0.06 mg/L and 0. 125-0.25 mg/L, respectively. Similar MICs were obtained for M. africanum (0.03-0.125 and 0.125-0.50 mg/L, respectively), and M. bovis (0.063-0.25 and 0.125-1.0 mg/L, respectively), but MICs were considerably lower for M. bovis BCG (0.008-0.063 mg/L for rifapentine and 0.016-0.125 mg/L for its metabolite). In general, MICs determined using 7H11 agar medium were usually one or two dilutions higher than those obtained using Bactec broth. When compared with rifampicin and rifabutin, the inhibitory activity of rifapentine for drug-susceptible isolates was roughly equal to that of rifabutin, and the inhibitory activity of 25-O:-desacetylrifapentine was comparable to that of rifampicin; however, rifapentine was somewhat more bactericidal than rifabutin at equal concentrations. Clinical isolates of M. tuberculosis with a high degree of resistance to rifampicin (MIC >/= 32 mg/L) were also highly resistant to rifabutin, rifapentine and 25-O:-desacetylrifapentine, although the MICs of rifabutin in this case were somewhat lower than the MICs of rifapentine.
Spiess, Tilmann; Desiere, Frank; Fischer, Peter; Spain, Jim C.; Knackmuss, Hans-Joachim; Lenke, Hiltrud
Mycobacterium sp. strain HL 4-NT-1, isolated from a mixed soil sample from the Stuttgart area, utilized 4-nitrotoluene as the sole source of nitrogen, carbon, and energy. Under aerobic conditions, resting cells of the Mycobacterium strain metabolized 4-nitrotoluene with concomitant release of small amounts of ammonia; under anaerobic conditions, 4-nitrotoluene was completely converted to 6-amino-m-cresol. 4-Hydroxylaminotoluene was converted to 6-amino-m-cresol by cell extracts and thus could be confirmed as the initial metabolite in the degradative pathway. This enzymatic equivalent to the acid-catalyzed Bamberger rearrangement requires neither cofactors nor oxygen. In the same crucial enzymatic step, the homologous substrate hydroxylaminobenzene was rearranged to 2-aminophenol. Abiotic oxidative dimerization of 6-amino-m-cresol, observed during growth of the Mycobacterium strain, yielded a yellow dihydrophenoxazinone. Another yellow metabolite (λmax, 385 nm) was tentatively identified as 2-amino-5-methylmuconic semialdehyde, formed from 6-amino-m-cresol by meta ring cleavage. PMID:9464378
Herrera-Sánchez, Diana Andrea; Castilla-Rodríguez, Jaisel Luz; Castrejón-Vázquez, María Isabel; Vargas-Camaño, María Eugenia; Medina-Torres, Edgar Alejandro; Blancas-Galicia, Lizbeth; Espinosa-Padilla, Sara Elva
Common variable immunodeficiency (CVID) is an heterogeneous group of disorders characterized by impaired antibody production. It shows a wide spectrum of manifestations including severe and recurrent respiratory infections (Streptococcus pneumoniae, Haemophilus) and gastrointestinal (Campylobacter jejuni, rotavirus and Giardia lamblia). Viral infections caused by herpes zoster, cytomegalovirus (CMV) and hepatitis C are rare. The opportunistic agents such as CMV, Pneumocystis jirovecii, cryptococcus and atypical mycobacteria have been reported as isolated cases. This paper reports the case of a 38-year-old female patient, who began six years before with weight loss of 7 kg in six months, fatigue, weakness, sweating, fever and abdominal pain. Furthermore, patient had intestinal obstruction and abdominal CT showed mesenteric lymph growth. The mesenteric lymph node biopsy revealed positives Mycobacterium PCR, Ziehl-Neelsen staining and culture for M. bovis. In the laparotomy postoperative period was complicated with nosocomial pneumonia, requiring mechanical ventilation and tracheostomy. Two years later, she developed right renal abscess that required surgical drainage, once again with a positive culture for Mycobacterium bovis. She was referred to highly specialized hospital and we documented panhypogammaglobulinemia and lymphopenia. Secondary causes of hypogammaglobulinemia were ruled out and common variable immunodeficiency (CVID) was confirmed, we started IVIG replacement. Four years later she developed mixed cellularity Hodgkin's lymphoma. Until today she continues with IVIG and chemotherapy. This report of a patient with CVID and Mycobacterium bovis infection, a unusual association, shows the cellular immunity susceptibility in this immunodeficiency, additional to the humoral defect.
Cohen-Bacrie, Stéphan; David, Marion; Stremler, Nathalie; Dubus, Jean-Christophe; Rolain, Jean-Marc; Drancourt, Michel
Mycobacterium chimaera is a recently described species within the Mycobacterium avium complex. Its pathogenicity in respiratory tract infection remains disputed. It has never been isolated during cystic fibrosis respiratory tract infection. An 11-year-old boy of Asian ethnicity who was born on Réunion Island presented to our hospital with cystic fibrosis after a decline in his respiratory function over the course of seven years. We found that the decline in his respiratory function was correlated with the persistent presence of a Mycobacterium avium complex organism further identified as M. chimaera. Using sequencing-based methods of identification, we observed that M. chimaera organisms contributed equally to respiratory tract infections in patients with cystic fibrosis when compared with M. avium subsp. hominissuis isolates. We believe that M. chimaera should be regarded as an emerging opportunistic respiratory pathogen in patients with cystic fibrosis, including young children, and that its detection warrants long-lasting appropriate anti-mycobacterial treatment to eradicate it.
Limia, A; Sangari, F J; Wagner, D; Bermudez, L E
Mycobacterium avium is both a pathogen that infects several hosts such as humans, pigs, and birds, as well as a microorganism that is encountered in environmental sources (soil and water). Protein secretion by the bacterium is likely to influence its ability to overcome adverse and competitive conditions both within or outside the host. Using a combination of cloning and information available in the databank, we characterized the secA gene from M. avium, encoding for a major preprotein translocase subunit associated with the secretion system of prokaryotics. In addition, we cloned the secA promoter sequence in a reporter construct upstream of a promoterless gfp. It was determined that the secA of M. avium shares large homology with the secA of Mycobacterium tuberculosis but not with secA of Mycobacterium leprae. secA expression was determined to be greater at logarithmic growth phase although it was also expressed at low levels during the stationary phase. secA expression was also observed when the bacteria were incubated in water as well as within human monocyte-derived macrophages and in conditions that are associated with biofilm formation. Future evaluation of the sec pathway in M. avium might provide important information about secreted proteins that are required for survival in different environments.
Background Mycobacterium chimaera is a recently described species within the Mycobacterium avium complex. Its pathogenicity in respiratory tract infection remains disputed. It has never been isolated during cystic fibrosis respiratory tract infection. Case presentation An 11-year-old boy of Asian ethnicity who was born on Réunion Island presented to our hospital with cystic fibrosis after a decline in his respiratory function over the course of seven years. We found that the decline in his respiratory function was correlated with the persistent presence of a Mycobacterium avium complex organism further identified as M. chimaera. Conclusion Using sequencing-based methods of identification, we observed that M. chimaera organisms contributed equally to respiratory tract infections in patients with cystic fibrosis when compared with M. avium subsp. hominissuis isolates. We believe that M. chimaera should be regarded as an emerging opportunistic respiratory pathogen in patients with cystic fibrosis, including young children, and that its detection warrants long-lasting appropriate anti-mycobacterial treatment to eradicate it. PMID:21939536
Kato, Hiromi; Saito, Masahiko; Nagahata, Yoshiko; Katayama, Yoko
The ability to degrade carbonyl sulfide (COS) was confirmed in seven bacterial strains that were isolated from soil, without the addition of COS. Comparative 16S rRNA gene sequence analysis indicated that these isolates belonged to the genera Mycobacterium, Williamsia and Cupriavidus. For example, Mycobacterium sp. strain THI401, grown on PYG agar medium, was able to degrade an initial level of 30 parts per million by volume COS within 1 h, while 60 % of the initial COS was decreased by abiotic conversion in 30 h. Considering natural COS flux between soil and the atmosphere, COS degradation by these bacteria was confirmed at an ambient level of 500 parts per trillion by volume (p.p.t.v.), using sterilized soil to cultivate the bacterium. Autoclave sterilization of soil resulted in a small amount of COS emission, while Mycobacterium spp. degraded COS at a faster rate than it was emitted from the soil, and reduced the COS mixing ratio to a level that was lower than the ambient level: THI401 degraded COS from an initial level of 530 p.p.t.v. to a level of 330 p.p.t.v. in 30 h. These results provide experimental evidence of microbial activity in soil as a sink for atmospheric COS.
Hasan, Nabeeh A; Warren, René L; Epperson, L Elaine; Malecha, Allyson; Alexander, David C; Turenne, Christine Y; MacMillan, Daniel; Birol, Inanc; Pleasance, Stephen; Coope, Robin; Jones, Steven J M; Romney, Marc G; Ng, Monica; Chan, Tracy; Rodrigues, Mabel; Tang, Patrick; Gardy, Jennifer L; Strong, Michael
Mycobacterium chimaera, a nontuberculous mycobacterium (NTM) belonging to the Mycobacterium avium complex (MAC), is an opportunistic pathogen that can cause respiratory and disseminated disease. We report the complete genome sequence of a strain, SJ42, isolated from an immunocompromised male presenting with MAC pneumonia, assembled from Illumina and Oxford Nanopore data. Copyright © 2017 Hasan et al.
Kwan, K; Ho, S T
We report a case of dual nontuberculous mycobacterial infections complicating an open distal radius and ulna fracture after polytrauma in a 35-year-old man. There was persistent wound discharge after definitive fixation of this fracture, but microbiological cultures did not yield any organism. The patient underwent multiple debridement, and subsequent tissue grew Mycobacterium chelonae and Mycobacterium fortuitum. Despite appropriate chemotherapy and surgical debridement the infection persisted until radical bone excision and tissue debridement were done. This case indicates that nontuberculous mycobacterial infections should be considered when conventional microbiological assays fail to identify the infecting agent in suspected osteomyelitis following open fracture. A combination of radical debridement, including removal of infected bone, and prolonged antimicrobial therapy are required to eradicate the infection completely.
Philipp, W J; Poulet, S; Eiglmeier, K; Pascopella, L; Balasubramanian, V; Heym, B; Bergh, S; Bloom, B R; Jacobs, W R; Cole, S T
An integrated map of the genome of the tubercle bacillus, Mycobacterium tuberculosis, was constructed by using a twin-pronged approach. Pulsed-field gel electrophoretic analysis enabled cleavage sites for Asn I and Dra I to be positioned on the 4.4-Mb circular chromosome, while, in parallel, clones from two cosmid libraries were ordered into contigs by means of fingerprinting and hybridization mapping. The resultant contig map was readily correlated with the physical map of the genome via the landmarked restriction sites. Over 165 genes and markers were localized on the integrated map, thus enabling comparisons with the leprosy bacillus, Mycobacterium leprae, to be undertaken. Mycobacterial genomes appear to have evolved as mosaic structures since extended segments with conserved gene order and organization are interspersed with different flanking regions. Repetitive sequences and insertion elements are highly abundant in M. tuberculosis, but the distribution of IS6110 is apparently nonrandom. Images Fig. 1 Fig. 2 PMID:8610181
Yang, Dongjun; Fu, Xin; He, Shiyi; Ning, Xueping
Mycobacterium avium (MA) belongs to the intracellular parasitic bacteria. To better understand how MA survives within macrophages and the different pathogenic mechanisms of MA and Mycobacterium tuberculosis (MTB), tandem mass tag (TMT) and liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis have been used to determine the proteins which are differentially expressed in MA-infected and MTB-infected macrophages. 369 proteins were found to be differentially expressed in MA-infected cells but not in MTB-infected cells. By using certain bioinformatics methods, we found the 369 proteins were involved in molecular function, biological process, and cellular component including binding, catalytic activity, metabolic process, cellular process, and cell part. In addition, some identified proteins were involved in multiple signaling pathways. These results suggest that MA probably survive within macrophages by affecting the expression of some crucial proteins. PMID:28573139
Bezerra, André Vinícius Andrade; Dos Reis, Emily Marques; Rodrigues, Rogério Oliveira; Cenci, Alexander; Cerva, Cristine; Mayer, Fabiana Quoos
Foodborne diseases are a public health problem worldwide. The consumption of contaminated raw milk has been recognized as a major cause of transmission of bovine tuberculosis to humans. Other mycobacteria that may be present in raw milk and may cause diseases are those belonging to the Mycobacterium avium complex. In this study, molecular biology tools were applied to investigate raw milk contamination with Mycobacterium spp. in family dairy farms from Rio Grande do Sul, southern Brazil. Furthermore, different variables related to the source of the milk, herd characteristics, and management were evaluated for their effect on milk contamination. Five hundred and two samples were analyzed, of which 354 were from the Northwest region (102 farms with samples from 93 bulk tanks and 261 animals) and 148 from the South region of the state (22 farms with samples from 23 bulk tanks and 125 animals). Among them, 10 (1.99%) and 7 (1.39%) were positive for Mycobacterium tuberculosis (9 confirmed as Mycobacterium bovis) and M. avium complexes, respectively. There was no difference in the frequencies of positive samples between the regions or the sample sources. Of the positive samples, 4 were collected from a bulk tank (1 positive for M. avium and 3 for M. tuberculosis). Moreover, 1 sample was positive concomitantly for M. tuberculosis and M. avium complexes. On risk analysis, no variable was associated with raw milk contamination by M. tuberculosis complex species. However, washing the udders of all animals and drying them with paper towels were weakly classified as risk factors for M. avium contamination. Positive samples were obtained from both animals and bulk tanks, which emphasizes the importance of tuberculosis control programs and provides evidence that milk monitoring can be used as a control practice. Moreover, the findings of this study reinforce the need for awareness of the problems of raw milk consumption among the general population.
Tórtola, M T; Lanéelle, M A; Martín-Casabona, N
Immunoglobulin G antibodies against two 2,3-diacyl trehalose (DAT) antigens from Mycobacterium tuberculosis (DATT) and Mycobacterium fortuitum (DATF) were studied by enzyme-linked immunosorbent assay of 356 serum samples. The sera were obtained from non-tuberculosis-infected individuals (282 serum samples) and tuberculosis patients (74 serum samples). Non-tuberculosis-infected individuals were healthy people (120 serum samples; positive purified-protein-derivative skin test, 60 patients; negative purified-protein-derivative skin test, 60 patients) patients with nontuberculosis lung disease (59 serum samples), contacts of sputum-smear-positive tuberculosis patients (57 serum samples), and human immunodeficiency virus-infected patients with nontuberculosis lung disease (46 serum samples). Of the 74 patients with tuberculosis, 14 were human immunodeficiency virus infected. The sensitivity of the method using DATT was 44.5%, and that with DATF was 48.6%. The specificities with both antigens were 99.1%. There were no significant differences between the mean values for both antigens (P = 0.2815). We therefore concluded that both antigens were interchangeable. As M. fortuitum, a fast-growing mycobacterium, could be a good source of antigen DAT, these results deserve consideration in the serology of tuberculosis. PMID:8877135
Gauthier, D T; Reece, K S; Xiao, J; Rhodes, M W; Kator, H I; Latour, R J; Bonzek, C F; Hoenig, J M; Vogelbein, W K
Striped bass (Morone saxatilis) in the Chesapeake Bay are currently experiencing a very high prevalence of mycobacteriosis associated with newly described Mycobacterium species, Mycobacterium pseudoshottsii and M. shottsii. The ecology of these mycobacteria outside the striped bass host is currently unknown. In this work, we developed quantitative real-time PCR assays for M. pseudoshottsii and M. shottsii and applied these assays to DNA extracts from Chesapeake Bay water and sediment samples, as well as to tissues from two dominant prey of striped bass, Atlantic menhaden (Brevoortia tyrannus) and bay anchovy (Anchoa mitchilli). Mycobacterium pseudoshottsii was found to be ubiquitous in water samples from the main stem of the Chesapeake Bay and was also present in water and sediments from the Rappahannock River, Virginia. M. pseudoshottsii was also detected in menhaden and anchovy tissues. In contrast, M. shottsii was not detected in water, sediment, or prey fish tissues. In conjunction with its nonpigmented phenotype, which is frequently found in obligately pathogenic mycobacteria of humans, this pattern of occurrence suggests that M. shottsii may be an obligate pathogen of striped bass.
Gauthier, D. T.; Reece, K. S.; Xiao, J.; Rhodes, M. W.; Kator, H. I.; Latour, R. J.; Bonzek, C. F.; Hoenig, J. M.; Vogelbein, W. K.
Striped bass (Morone saxatilis) in the Chesapeake Bay are currently experiencing a very high prevalence of mycobacteriosis associated with newly described Mycobacterium species, Mycobacterium pseudoshottsii and M. shottsii. The ecology of these mycobacteria outside the striped bass host is currently unknown. In this work, we developed quantitative real-time PCR assays for M. pseudoshottsii and M. shottsii and applied these assays to DNA extracts from Chesapeake Bay water and sediment samples, as well as to tissues from two dominant prey of striped bass, Atlantic menhaden (Brevoortia tyrannus) and bay anchovy (Anchoa mitchilli). Mycobacterium pseudoshottsii was found to be ubiquitous in water samples from the main stem of the Chesapeake Bay and was also present in water and sediments from the Rappahannock River, Virginia. M. pseudoshottsii was also detected in menhaden and anchovy tissues. In contrast, M. shottsii was not detected in water, sediment, or prey fish tissues. In conjunction with its nonpigmented phenotype, which is frequently found in obligately pathogenic mycobacteria of humans, this pattern of occurrence suggests that M. shottsii may be an obligate pathogen of striped bass. PMID:20656856
Appleyard, Greg D.; Clark, Edward G.
Three cases of feline atypical mycobacteriosis from different geographical regions in North America were characterized by large clusters of filamentous bacteria visible on hematoxylin-and-eosin-stained tissue sections. PCR amplification demonstrated the presence of Mycobacterium-specific nucleic acid in samples of skin lesions from these cases. PCR-assisted cloning and DNA sequence analysis of a 541-bp length of the Mycobacterium 16S rRNA gene generated DNA sequences which were >95% identical, suggesting that the three isolates were closely related. Two of the sequences were 99% identical and may represent the same species. Alignment with comparable 16S rRNA gene sequences from 66 Mycobacterium species and partially characterized isolates highlighted similarities (>94%) with Mycobacterium bohemicum, Mycobacterium haemophilum, Mycobacterium ulcerans, Mycobacterium avium subsp. avium, and isolate IWGMT 90242. Parsimony analysis of sequence data suggested relatedness to M. leprae. Significant molecular genetic and pathobiological differences between these three similar isolates and other known species of mycobacteria suggested that the organisms may not have been described previously and that these cases may represent a new form of mycobacterial disease in cats. We suggest the term “Mycobacterium visibilis” to describe the organism from which the two nearly identical sequences were obtained. PMID:12089257
Hurtado, U A; Solano, J S; Rodriguez, A; Robledo, J; Rouzaud, F
Mycobacterium africanum is a member of the Mycobacterium tuberculosis complex. Most commonly found in West African countries, it has scarcely been described in South America. Here, we report the first genome sequence of a Colombian M. africanum clinical isolate. It is composed of 4,493,502 bp, with 4,069 genes.
Mycobacterium bovis is the cause of tuberculosis in most animal species, including cattle and is a serious zoonotic pathogen. In humans, M. bovis infection can result in disease clinically indistinguishable from that caused by Mycobacterium tuberculosis, the cause of most tuberculosis in humans. Reg...
Background Over the past two decades, highly virulent strains of Mycobacterium tuberculosis have emerged and spread rapidly in humans, suggesting a selective advantage based upon virulence. A similar scenario has not been described for Mycobacterium bovis infection in cattle (i.e., Bovine Tuberculos...
Mycobacterium avium subspecies paratuberculosis (Map)-specific proteins (35) were identified by comparing the proteomes of Map isolates with those of the genetically similar subspecies IS901+ Mycobacterium avium subspecies avium or silvaticum. This approach identified subspecies-specific proteins in...
Han, Xiang Y; Quintanilla, Marco
A 43-year-old woman of Mayan origin from Quintana Roo, Mexico, was diagnosed with diffuse lepromatous leprosy. The etiologic bacillus was determined to be Mycobacterium lepromatosis instead of Mycobacterium leprae. This case likely represents the first report of this leprosy form and its agent in the southeastern tip of Mexico. Copyright © 2015, American Society for Microbiology. All Rights Reserved.
A 43-year-old woman of Mayan origin from Quintana Roo, Mexico, was diagnosed with diffuse lepromatous leprosy. The etiologic bacillus was determined to be Mycobacterium lepromatosis instead of Mycobacterium leprae. This case likely represents the first report of this leprosy form and its agent in the southeastern tip of Mexico. PMID:26311856
... Nucleic Acid-Based Systems for Mycobacterium tuberculosis Complex in Respiratory Specimens AGENCY: Food...) is proposing to reclassify nucleic acid-based in vitro diagnostic devices for the detection of... Controls Guideline: Nucleic Acid-Based In Vitro Diagnostic Devices for the Detection of Mycobacterium...
Branger, Maxime; Hauer, Amandine; Michelet, Lorraine; Karoui, Claudine; Cochard, Thierry; De Cruz, Krystel; Henault, Sylvie
Mycobacterium bovis is the etiologic agent of bovine tuberculosis, a chronic infectious disease, affecting livestock, wild animals, and sometimes humans. We report the draft genome sequence of a Mycobacterium bovis strain isolated from wild boar of spoligotype SB0120 (or BCG-like) also present in wildlife-livestock multi-host systems. PMID:27834714
Pin, Didier; Guérin-Faublée, Véronique; Garreau, Virginie; Breysse, Franck; Dumitrescu, Oana; Flandrois, Jean-Pierre; Lina, Gerard
Bovine nodular thelitis is a granulomatous dermatitis associated with infection with acid-fast bacteria. To identify the mycobacterium responsible for this infection, we conducted phylogenetic investigations based on partial sequencing of 6 genes. These bacteria were identified as an undescribed Mycobacterium species that was phylogenetically related to M. leprae and M. lepromatosis.
Lawsin, Adrian; Perry, K. Allison; Alyanak, Efe; Toney, Nadege C.; Malecha, Allyson; Rowe, Lori A.; Batra, Dhwani; Moulton-Meissner, Heather; Miller, Jeffrey R.; Strong, Michael; Laufer Halpin, Alison
ABSTRACT Mycobacterium chimaera is a nontuberculous mycobacterium species commonly found in the environment. Here, we report the first complete genome sequence of a strain from the investigation of invasive infections following open-heart surgeries that used contaminated LivaNova Sorin Stockert 3T heater-cooler devices. PMID:28774973
Das, Sarbashis; Pettersson, B.M. Fredrik; Behra, Phani Rama Krishna; Ramesh, Malavika; Dasgupta, Santanu; Bhattacharya, Alok; Kirsebom, Leif A.
We provide the genome sequences of the type strains of the polychlorophenol-degrading Mycobacterium chlorophenolicum (DSM43826), the degrader of chlorinated aliphatics Mycobacterium chubuense (DSM44219) and Mycobacterium obuense (DSM44075) that has been tested for use in cancer immunotherapy. The genome sizes of M. chlorophenolicum, M. chubuense, and M. obuense are 6.93, 5.95, and 5.58 Mb with GC-contents of 68.4%, 69.2%, and 67.9%, respectively. Comparative genomic analysis revealed that 3,254 genes are common and we predicted approximately 250 genes acquired through horizontal gene transfer from different sources including proteobacteria. The data also showed that the biodegrading Mycobacterium spp. NBB4, also referred to as M. chubuense NBB4, is distantly related to the M. chubuense type strain and should be considered as a separate species, we suggest it to be named Mycobacterium ethylenense NBB4. Among different categories we identified genes with potential roles in: biodegradation of aromatic compounds and copper homeostasis. These are the first nonpathogenic Mycobacterium spp. found harboring genes involved in copper homeostasis. These findings would therefore provide insight into the role of this group of Mycobacterium spp. in bioremediation as well as the evolution of copper homeostasis within the Mycobacterium genus. PMID:26079817
De Rossi, Edda; Branzoni, Manuela; Cantoni, Rita; Milano, Anna; Riccardi, Giovanna; Ciferri, Orio
The mmr gene, cloned from Mycobacterium tuberculosis, was shown to confer to Mycobacterium smegmatis resistance to tetraphenylphosphonium (TPP), erythromycin, ethidium bromide, acriflavine, safranin O, and pyronin Y. The gene appears to code for a protein containing four transmembrane domains. Studies of [3H]TPP intracellular accumulation strongly suggest that the resistance mediated by the Mmr protein involves active extrusion of TPP. PMID:9811672
Jaén-Luchoro, Daniel; Seguí, Carolina; Aliaga-Lozano, Francisco; Salvà-Serra, Francisco; Busquets, Antonio; Gomila, Margarita; Ramírez, Antonio; Ruiz, Mikel; Lalucat, Jorge
Here, we report the complete genome sequence of Mycobacterium immunogenum type strain CCUG 47286, a nontuberculous mycobacterium. The whole genome has 5,573,781 bp and covers as many as 5,484 predicted genes. This genome contributes to the task of closing the still-existing gap of genomes of rapidly growing mycobacterial type strains. PMID:27231356
We report the draft genome sequences of ten Mycobacterium avium complex isolates obtained from diverse hosts. This collection includes isolates obtained from deer, pig, elephant, ruddy duck and Red-tailed hawk species. The type strain of Mycobacterium avium subspecies silvaticum (ATCC 49884) is also...
McMullen, Allison R; Mattar, Caline; Kirmani, Nigar; Burnham, Carey-Ann D
Mycobacterium spp. are a rare cause of endocarditis. Herein, we describe a case of Mycobacterium mageritense prosthetic valve endocarditis. This organism produced an unusual brown pigment on solid media. Cultures of valve tissue for acid-fast bacilli might be considered in some cases of apparently culture-negative prosthetic valve endocarditis.
In this study we investigated an iron dependent regulator (IdeR) of Mycobacterium avium subsp. paratuberculosis (MAP). IdeR is a transcriptional factor that plays a global iron regulatory role in Mycobacterium tuberculosis (MTB) with a 19-bp recognition sequence. IdeR recognition sites within MAP ge...
Dai, Jianli; Chen, Yuansha; Lauzardo, Michael
Mycobacteria include a large number of pathogens. Identification to species level is important for diagnoses and treatments. Here, we report the development of a Web-accessible database of the hsp65 locus sequences (http://msis.mycobacteria.info) from 149 out of 150 Mycobacterium species/subspecies. This database can serve as a reference for identifying Mycobacterium species. PMID:21450960
Slany, Michal; Jezek, Petr; Fiserova, Vera; Bodnarova, Monika; Stork, Jiri; Havelkova, Marta; Kalat, Frantisek; Pavlik, Ivo
The low frequency of nontuberculous mycobacterial infections, nonspecific symptoms for individual mycobacteria, and the lack of specific identification methods could alter correct diagnosis. This study presents a combined microbiology and molecular-based approach for Mycobacterium marinum detection in four aquarists with cutaneous mycobacterial infection. Simultaneously, ecology screening for M. marinum presence in the aquarists' fish tanks was performed. A total of 38 mycobacterial isolates originated from four human patients (n = 20), aquarium animals (n = 8), and an aquarium environment (n = 10). Isolate identification was carried out using 16S rRNA sequence analysis. A microbiology-based approach, followed by 16S rRNA sequence analysis, was successfully used for detection of M. marinum in all four patients. Animal and environmental samples were simultaneously examined, and a total of seven mycobacterial species were isolated: Mycobacterium chelonae , Mycobacterium fortuitum , Mycobacterium gordonae , Mycobacterium kansasii , Mycobacterium mantenii , Mycobacterium marinum , and Mycobacterium peregrinum . The presence of M. marinum was proven in the aquarium environments of two patients. Although M. marinum is described as being present in water, it was detected only in fish.
Despite the ubiquitous occurrence of Mycobacterium sp. in nature and the fact that Johne’s disease has been reported worldwide, little research has been done to assess the survival of Mycobacterium avium subsp. paratuberculosis (M. paratuberculosis) in agricultural environments. The goal of this stu...
Bovine tuberculosis is a ‘neglected zoonosis’ and its contribution to the proportion of Mycobacterium tuberculosis complex infections in humans is unknown. A retrospective study on archived Mycobacterium tuberculosis complex (MTC) isolates from a reference laboratory in Uganda was undertaken to iden...
Weile, Jan; Eickmeyer, Holm; Dreier, Jens; Liebke, Michael; Fuchs, Uwe; Wittke, Johann-Wolfgang; Richter, Elvira; Gummert, Jan; Knabbe, Cornelius; Schulz, Uwe
We report the first documented case of a Mycobacterium tuberculosis transmission by an orthotopic heart transplantation from the donor to the recipient. Mycobacterium tuberculosis positive blood culture showed systemic prevalence of the Mycobacteria, however, prophylactic therapy was able to prevent a clinical manifestation of tuberculosis in the recipient.
He, Xiu-yun; Zhuang, Yu-hui; Zhang, Xiao-gang
To evaluate the potential of recombinant 38000 protein of Mycobacterium tuberculosis (38000 protein) as a tuberculosis-specific tuberculin for screening M. tuberculosis infection. A total of 1342 subjects (706 men and 636 women, age 18-60 years) from several communities in Kazuo County and Xidaziying Town, Chaoyang, Liaoning Province, and Hongdong County, Linfen, Shanxi Province were enrolled from September 2004 to February 2005. The skin tests were performed with double-blinded and the intradermal injections were administered on both forearms with 0.1 ml solution of PPD and 38000 protein at the right side and the left side, respectively. The vertical and transverse diameters of induration or erythema were measured following 24 h for 38000 protein and 48 h for PPD, respectively. The diameters of the the skin test reactions were defined as the means of the vertical and transverse diameters, and positive skin reactions were identified when the diameter was greater than or equal to 5 mm. The comparison of the positive rate was performed via chi(2) test and the consistency of positive skin test reactions between 38000 protein and TB-PPD was analyzed through calculating Kappa coefficients. The positive rate was 55.1% (740/1342) and 28.6% (384/1342) for PPD and 38000 protein, respectively; the difference being significant (chi(2) = 190.6, P < 0.01). The consistency of positive skin test reactions between 38000 protein and PPD was low due to a negative Kappa coefficient. The positive rates induced by PPD and 38000 protein tended to increase with age except for the 33-37 year group. For a given age group, the positive rate of PPD was much higher than that of 38000 protein. The subjects without BCG scar had a lower positive rate for 38000 protein (24.3%, 137/566) than those with BCG scar (31.9%, 247/776) (chi(2) = 4.7, P < 0.05). The subjects with tuberculosis contact history had a higher positive rate for 38000 protein (74.4%, 32/43) than those without tuberculosis contact
Background The sequence of the pathogen Mycobacterium tuberculosis (Mtb) strain H37Rv has been available for over a decade, but the biology of the pathogen remains poorly understood. Genome sequences from other Mtb strains and closely related bacteria present an opportunity to apply the power of comparative genomics to understand the evolution of Mtb pathogenesis. We conducted a comparative analysis using 31 genomes from the Tuberculosis Database (TBDB.org), including 8 strains of Mtb and M. bovis, 11 additional Mycobacteria, 4 Corynebacteria, 2 Streptomyces, Rhodococcus jostii RHA1, Nocardia farcinia, Acidothermus cellulolyticus, Rhodobacter sphaeroides, Propionibacterium acnes, and Bifidobacterium longum. Results Our results highlight the functional importance of lipid metabolism and its regulation, and reveal variation between the evolutionary profiles of genes implicated in saturated and unsaturated fatty acid metabolism. It also suggests that DNA repair and molybdopterin cofactors are important in pathogenic Mycobacteria. By analyzing sequence conservation and gene expression data, we identify nearly 400 conserved noncoding regions. These include 37 predicted promoter regulatory motifs, of which 14 correspond to previously validated motifs, as well as 50 potential noncoding RNAs, of which we experimentally confirm the expression of four. Conclusions Our analysis of protein evolution highlights gene families that are associated with the adaptation of environmental Mycobacteria to obligate pathogenesis. These families include fatty acid metabolism, DNA repair, and molybdopterin biosynthesis. Our analysis reinforces recent findings suggesting that small noncoding RNAs are more common in Mycobacteria than previously expected. Our data provide a foundation for understanding the genome and biology of Mtb in a comparative context, and are available online and through TBDB.org. PMID:22452820
Peterson, Tracy S.; Ferguson, Jayde A.; Watral, Virginia G.; Mutoji, K. Nadine; Ennis, Don G.; Kent, Michael L.
Mycobacterial infections in laboratory zebrafish (Danio rerio) are common and widespread in research colonies. Mycobacteria within free living amoebae have been shown to be transmission vectors for mycobacteriosis. Paramecium caudatum are commonly used as a first food for zebrafish, and we investigated this ciliate’s potential to serve as a vector of Mycobacterium marinum and M. chelonae. The ability of live P. caudatum to transmit these mycobacteria to larval, juvenile and adult zebrafish was evaluated. Infections were defined by histologic observation of granulomas containing acid-fast bacteria in extraintestinal locations. In both experiments, fish fed paramecia containing mycobacteria became infected at a higher incidence than controls. Larvae (exposed at 4 days post hatch) fed paramecia with M. marinum exhibited an incidence of 30% (24/80) and juveniles (exposed at 21 days post hatch) showed 31% incidence (14/45). Adult fish fed a gelatin food matrix containing mycobacteria within paramecia or mycobacteria alone for 2 wk resulted in infections when examined 8 wk after exposure as follows: M. marinum OSU 214 47% (21/45), M. marinum CH 47% (9/19), M. chelonae 38% (5/13). In contrast, fish feed mycobacteria alone in this diet did not become infected, except for 2 fish (5%) in the M. marinum OSU 214 low dose group. These results demonstrate that Paramecium caudatum can act as a vector for mycobacteria. This provides a useful animal model for evaluation of natural mycobacterial infections and demonstrates the possibility of mycobacterial transmission in zebrafish facilities via contaminated paramecia cultures. PMID:24192000
Biet, Franck; Boschiroli, Maria Laura; Thorel, Marie Françoise; Guilloteau, Laurence A
Pathogens that are transmitted between the environment, wildlife, livestock and humans represent major challenges for the protection of human and domestic animal health, the economic sustainability of agriculture, and the conservation of wildlife. Among such pathogens, the genus Mycobacterium is well represented by M. bovis, the etiological agent of bovine tuberculosis, M. avium ssp. paratuberculosis (Map) the etiological agent of Johne disease, M. avium ssp. avium (Maa) and in a few common cases by other emergent environmental mycobacteria. Epidemiologic surveys performed in Europe, North America and New Zealand have demonstrated the existence and importance of environmental and wildlife reservoirs of mycobacterial infections that limit the attempts of disease control programmes. The aim of this review is to examine the zoonotic aspects of mycobacteria transmitted from the environment and wildlife. This work is focused on the species of two main groups of mycobacteria classified as important pathogens for humans and animals: first, M. bovis, the causative agent of bovine tuberculosis, which belongs to the M. tuberculosis complex and has a broad host range including wildlife, captive wildlife, domestic livestock, non-human primates and humans; the second group examined, is the M. avium-intracellulare complex (MAC) which includes M. avium ssp. avium causing major health problems in AIDS patients and M. avium ssp. paratuberculosis the etiological agent of Johne disease in cattle and identified in patients with Crohn disease. MAC agents, in addition to a broad host range, are environmental mycobacteria found in numerous biotopes including the soil, water, aerosols, protozoa, deep litter and fresh tropical vegetation. This review examines the possible reservoirs of these pathogens in the environment and in wildlife, their role as sources of infection in humans and animals and their health impact on humans. The possibilities of control and management programmes for
Nouioui, Imen; Carro, Lorena; Teramoto, Kanae; Igual, José M; Jando, Marlen; Del Carmen Montero-Calasanz, Maria; Sutcliffe, Iain; Sangal, Vartul; Goodfellow, Michael; Klenk, Hans-Peter
A polyphasic study was undertaken to establish the taxonomic position of a non-chromogenic, rapidly growing Mycobacterium strain that had been isolated from sputum. The strain, CECT 8775T, has chemotaxonomic and cultural properties consistent with its classification in the genus Mycobacterium and was distinguished from the type strains of closely related mycobacterial species, notably from Mycobacterium paraense DSM 46749T, its nearest phylogenetic neighbour, based on 16S rRNA, hsp65 and rpoB gene sequence data. These organisms were also distinguished by a broad range of chemotaxonomic and phenotypic features and by a digital DNA-DNA relatedness value of 22.8 %. Consequently, the strain is considered to represent a novel species of Mycobacterium for which the name Mycobacterium eburneum sp. nov is proposed; the type strain is X82T (CECT 8775T=DSM 44358T).
Koizumi, Yusuke; Shimizu, Kaoru; Shigeta, Masayo; Minamiguchi, Hitoshi; Hodohara, Keiko; Andoh, Akira; Tanaka, Toshihide; Chikamatsu, Kinuyo; Mitarai, Satoshi; Mikamo, Hiroshige
A 40-year-old man complaining of progressive body weight loss was diagnosed to have acquired immunodeficiency syndrome. Within 2 weeks after the initiation of combination antiretroviral therapy, he developed fever, massive cervical lymphadenopathy and a protruding subcutaneous abscess. A lymph node biopsy and abscess drainage revealed non-caseous granuloma and mycobacterium. The mycobacterium belonged to Runyon II group, but it showed no matches to any previously reported species. According to sequence analyses, the strain was identified as Mycobacterium shigaense. After six months of antimycobacterial treatment, the lesions were all successfully cured. This is the third case report of the novel mycobacterium, M. shigaense, presenting in associatioin with immune reconstitution syndrome. PMID:27853087
Role of GenoType(®) Mycobacterium Common Mycobacteria/Additional Species Assay for Rapid Differentiation Between Mycobacterium tuberculosis Complex and Different Species of Non-Tuberculous Mycobacteria.
Singh, Amresh Kumar; Maurya, Anand Kumar; Umrao, Jyoti; Kant, Surya; Kushwaha, Ram Awadh Singh; Nag, Vijaya Laskshmi; Dhole, Tapan N
Mycobacterium tuberculosis complex (MTBC) and non-tuberculous mycobacteria (NTM) may or may not have same clinical presentations, but the treatment regimens are always different. Laboratory differentiation between MTBC and NTM by routine methods are time consuming and cumbersome to perform. We have evaluated the role of GenoType(®) Mycobacterium common mycobacteria/additional species (CM/AS) assay for differentiation between MTBC and different species of NTM in clinical isolates from tuberculosis (TB) cases. A total of 1080 clinical specimens were collected from January 2010 to June 2012. Diagnosis was performed by Ziehl-Neelsen staining followed by culture in BacT/ALERT 3D system (bioMerieux, France). A total of 219 culture positive clinical isolates (BacT/ALERT(®) MP cultures) were selected for differentiation by p-nitrobenzoic acid (PNB) sensitivity test as and BIO-LINE SD Ag MPT64 TB test considering as the gold standard test. Final identification and differentiation between MTBC and different species of NTM were further confirmed by GenoType(®) Mycobacterium CM/AS assay (Hain Lifescience, Nehren, Germany). Out of 219 BacT/ALERT(®) MP culture positive isolates tested by PNB as 153 MTBC (69.9%) and by GenoType(®) Mycobacterium CM/AS assay as 159 (72.6%) MTBC and remaining 60 (27.4%) were considered as NTM species. The GenoType(®) Mycobacterium CM/AS assay was proved 99.3% sensitive and 98.3% specific for rapid differentiation of MTBC and NTM. The most common NTM species were; Mycobacterium fortuitum 20 (33.3%) among rapid growing mycobacteria and Mycobacterium intracellulare 11 (18.3%) among slow growing mycobacteria. The GenoType(®) Mycobacterium assay makes rapid and accurate identification of NTM species as compared with different phenotypic and molecular diagnostic tool and helps in management of infections caused by different mycobacteria.
Kelkar, Dhanashree S; Kumar, Dhirendra; Kumar, Praveen; Balakrishnan, Lavanya; Muthusamy, Babylakshmi; Yadav, Amit Kumar; Shrivastava, Priyanka; Marimuthu, Arivusudar; Anand, Sridhar; Sundaram, Hema; Kingsbury, Reena; Harsha, H C; Nair, Bipin; Prasad, T S Keshava; Chauhan, Devendra Singh; Katoch, Kiran; Katoch, Vishwa Mohan; Kumar, Prahlad; Chaerkady, Raghothama; Ramachandran, Srinivasan; Dash, Debasis; Pandey, Akhilesh
The genome sequencing of H37Rv strain of Mycobacterium tuberculosis was completed in 1998 followed by the whole genome sequencing of a clinical isolate, CDC1551 in 2002. Since then, the genomic sequences of a number of other strains have become available making it one of the better studied pathogenic bacterial species at the genomic level. However, annotation of its genome remains challenging because of high GC content and dissimilarity to other model prokaryotes. To this end, we carried out an in-depth proteogenomic analysis of the M. tuberculosis H37Rv strain using Fourier transform mass spectrometry with high resolution at both MS and tandem MS levels. In all, we identified 3176 proteins from Mycobacterium tuberculosis representing ~80% of its total predicted gene count. In addition to protein database search, we carried out a genome database search, which led to identification of ~250 novel peptides. Based on these novel genome search-specific peptides, we discovered 41 novel protein coding genes in the H37Rv genome. Using peptide evidence and alternative gene prediction tools, we also corrected 79 gene models. Finally, mass spectrometric data from N terminus-derived peptides confirmed 727 existing annotations for translational start sites while correcting those for 33 proteins. We report creation of a high confidence set of protein coding regions in Mycobacterium tuberculosis genome obtained by high resolution tandem mass-spectrometry at both precursor and fragment detection steps for the first time. This proteogenomic approach should be generally applicable to other organisms whose genomes have already been sequenced for obtaining a more accurate catalogue of protein-coding genes.
Lecorche, Emmanuel; Haenn, Sophie; Mougari, Faiza; Kumanski, Sylvain; Veziris, Nicolas; Benmansour, Hanaa; Raskine, Laurent; Moulin, Laurent; Cambau, Emmanuelle
Mycobacterium chimaera is a recently described nontuberculous mycobacterium belonging to the M. avium complex (MAC). Because this species is implicated in a worldwide outbreak due to contaminated heater-cooler unit water tanks during open-heart surgery, it becomes mandatory for clinical microbiology laboratories to be able to differentiate M. chimaera from the other MAC species, especially M. intracellulare. Such identification was so far restricted to specialized laboratories, since it required the analysis of several gene sequences. The aim of this study was to evaluate commercialized methods for identifying M. chimaera with regard to the reference gene sequencing ITS, the internal transcribed spacer 16-23S. 47 clinical and environmental isolates including 41 MAC were identified using (i) PCR sequencing of the ITS gene and of the hsp65 gene, (ii) three molecular biology kits (INNO-LiPA Mycobacteria, GenoType Mycobacterium CM and GenoType NTM-DR), and (iii) matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) using MicroFlex software. There was a high concordance for species determination between the reference ITS sequencing and the GenoType NTM-DR test (39/41, 95%), the INNO-LiPA test (38/41, 93%) and the hsp65 sequencing (38/41, 93%). The GenoType CM test did not distinguish M. chimaera from M. intracellulare. MALDI-TOF MS distinguished two M. chimaera - M. intracellulare groups separated from M. avium and from the other mycobacterial species on a score-oriented dendrogram, but did not differentiate the two species either. This study showed that INNO-LiPA and Genotype NTM-DR are efficient assays for M. chimaera identification in clinical microbiology laboratories. Copyright © 2017. Published by Elsevier Ltd.
Trojanowski, Damian; Ginda, Katarzyna; Pióro, Monika; Hołówka, Joanna; Skut, Partycja; Jakimowicz, Dagmara; Zakrzewska-Czerwińska, Jolanta
It has recently been demonstrated that bacterial chromosomes are highly organized, with specific positioning of the replication initiation region. Moreover, the positioning of the replication machinery (replisome) has been shown to be variable and dependent on species-specific cell cycle features. Here, we analyzed replisome positions in Mycobacterium smegmatis, a slow-growing bacterium that exhibits characteristic asymmetric polar cell extension. Time-lapse fluorescence microscopy analyses revealed that the replisome is slightly off-center in mycobacterial cells, a feature that is likely correlated with the asymmetric growth of Mycobacterium cell poles. Estimates of the timing of chromosome replication in relation to the cell cycle, as well as cell division and chromosome segregation events, revealed that chromosomal origin-of-replication (oriC) regions segregate soon after the start of replication. Moreover, our data demonstrate that organization of the chromosome by ParB determines the replisome choreography. Despite significant progress in elucidating the basic processes of bacterial chromosome replication and segregation, understanding of chromosome dynamics during the mycobacterial cell cycle remains incomplete. Here, we provide in vivo experimental evidence that replisomes in Mycobacterium smegmatis are highly dynamic, frequently splitting into two distinct replication forks. However, unlike in Escherichia coli, the forks do not segregate toward opposite cell poles but remain in relatively close proximity. In addition, we show that replication cycles do not overlap. Finally, our data suggest that ParB participates in the positioning of newly born replisomes in M. smegmatis cells. The present results broaden our understanding of chromosome segregation in slow-growing bacteria. In view of the complexity of the mycobacterial cell cycle, especially for pathogenic representatives of the genus, understanding the mechanisms and factors that affect chromosome
Jimenez, I. Y.; Bartha, R.
The biodegradation of polycyclic aromatic hydrocarbon pollutants is constrained, in part, by their solid physical state and very low water solubility. Searching for ways to overcome these limitations, we isolated from soil a bacterium capable of growing on pyrene as a sole source of carbon and energy. Acid-fast stain, morphology, and fatty acid profile identified it as a Mycobacterium sp. In a mineral salts solution, the isolate mineralized 50% of a 250-(mu)g/ml concentration of [(sup14)C]pyrene in 2 to 3 days. Detergent below the critical micelle concentration increased the pyrene mineralization rate to 154%, but above the critical micelle concentration, the detergent severely inhibited pyrene mineralization. The water-miscible solvent polyethylene glycol was inhibitory. The hydrophobic solvents heptamethylnonane, decalin, phenyldecane, and diphenylmethane were also inhibitory at several concentrations tested, but the addition of paraffin oil, squalene, squalane, tridecylcyclohexane, and cis-9-tricosene at 0.8% (vol/vol) doubled pyrene mineralization rates by the Mycobacterium sp. without being utilized themselves. The Mycobacterium sp. was found to have high cell surface hydrophobicity and adhered to the emulsified solvent droplets that also contained the dissolved pyrene, facilitating its mass transfer to the degrading bacteria. Cells physically adhering to solvent droplets metabolized pyrene 8.5 times as fast as cells suspended in the aqueous medium. An enhanced mass transfer of polycyclic aromatic hydrocarbon compounds to microorganisms by suitable hydrophobic solvents might allow the development of solvent-augmented biodegradation techniques for use in aqueous or slurry-type bioreactors. PMID:16535350
Burge, E.J.; Gauthier, David T.; Ottinger, C.A.; Van Veld, P.A.
In mammals, the natural resistance-associated macrophage protein 1 gene, Nramp1, plays a major role in resistance to mycobacterial infections. Chesapeake Bay striped bass (Morone saxatilis) is currently experiencing an epizootic of mycobacteriosis that threatens the health of this ecologically and economically important species. In the present study, we characterized an Nramp gene in this species and obtained evidence that there is induction following Mycobacterium exposure. The striped bass Nramp gene (MsNramp) and a 554-amino-acid sequence contain all the signal features of the Nramp family, including a topology of 12 transmembrane domains (TM), the transport protein-specific binding-protein-dependent transport system inner membrane component signature, three N-linked glycosylation sites between TM 7 and TM 8, sites of casein kinase and protein kinase C phosphorylation in the amino and carboxy termini, and a tyrosine kinase phosphorylation site between TM 6 and TM 7. Phylogenetic analysis most closely grouped MsNramp with other teleost Nramp genes and revealed high sequence similarity with mammalian Nramp2. MsNramp expression was present in all tissues assayed by reverse transcription-PCR. Within 1 day of injection of Mycobacterium marinum, MsNramp expression was highly induced (17-fold higher) in peritoneal exudate (PE) cells compared to the expression in controls. The levels of MsNramp were three- and sixfold higher on days 3 and 15, respectively. Injection of Mycobacterium shottsii resulted in two-, five-, and threefold increases in gene expression in PE cells over the time course. This report is the first report of induction of an Nramp gene by mycobacteria in a poikilothermic vertebrate.
Konrads, Christian; Rückl, Kilian; El Tabbakh, Mohammed; Rudert, Maximilian; Kircher, Stefan; Plumhoff, Piet
Introduction: Septic olecranon bursitis due to atypical mycobacteria is rare. An insidious beginning can delay diagnosis and treatment. Antibacterial therapy recommendations are not well-defined for bursitis caused by atypical mycobacteria. We present a rare case of olecranon bursitis caused by Mycobacterium gordonae, reporting our experiences regarding pathogen identification and antibiotic therapy, which differs from regimes used in common septic bursitis mostly caused by staphylococcus aureus. Methods: A 35-year-old male with bursitis olecrani received open bursectomy. Microbiological culture did not reveal bacteria. Due to wound healing complications revision surgery was performed four weeks postoperatively. Finally, Mycobacterium gordonae was identified by PCR and an antibiogram could be developed. A triple antimicrobial combination therapy with Rifampicin, Clarithromycin, and Ethambutol was administered systemically for 12 months. The patient was followed-up for 24 months. Results: After the second operation with pathogen identification and antibiotic combination therapy the wound healed without any additional complications. At last follow-up 24 months after the first surgery with bursectomy and 23 months after revision surgery with debridement, the patient was still pain free with no significant clinical findings or tenderness to touch at the operation site. Elbow range of motion was full. Discussion: As septic bursitis can be caused by many different and sometimes rare and difficult to identify bacteria, intraoperative probes should be taken and histopathological and microbiological analysis should be conducted, including PCR. In a young man with olecranon bursitis due to Mycobacterium gordonae surgical treatment and an antibiotic combination therapy showed a good clinical outcome after one and two years. PMID:27892398
Numerical taxonomy of mycobactin-dependent mycobacteria, emended description of Mycobacterium avium, and description of Mycobacterium avium subsp. avium subsp. nov., Mycobacterium avium subsp. paratuberculosis subsp. nov., and Mycobacterium avium subsp. silvaticum subsp. nov.
Thorel, M F; Krichevsky, M; Lévy-Frébault, V V
We performed a numerical taxonomy analysis of 38 Mycobacterium paratuberculosis and related mycobacterial strains, including wood pigeon mycobacteria; this analysis was based on 22 tests, which were selected for their potential discriminative value from a total of 51 tests studied and produced four well-defined clusters. Cluster 1 contained the M. paratuberculosis strains, including two strains isolated from Crohn's disease patients; cluster 2 contained Mycobacterium avium and Mycobacterium intracellulare reference strains; cluster 3 consisted of the wood pigeon mycobacteria; and the only strain in cluster 4 was M. paratuberculosis 316F, which is used for antigen and vaccine production. Strains in cluster 1 were mycobactin dependent even when they were subcultured, whereas strains in cluster 3 were unable to grow on egg medium and their growth was stimulated by pH 5.5. Growth stimulation by pyruvate, resistance to D-cycloserine (50 micrograms/ml), and alkaline phosphatase activity also were characteristics that were useful for discriminating between clusters 1 and 3. The results of previous DNA-DNA hybridization studies have demonstrated that M. avium Chester 1901, M. paratuberculosis Bergey et al. 1923, and the wood pigeon mycobacteria belong to a single genomic species, and we propose that the name of this species should be M. avium. On the basis of the results of previous genomic analyses based on restriction fragment length, the results of polymorphism studies, and DNA patterns determined by field inversion gel electrophoresis as well as the results of our phenotypic study, we propose that the species should be divided into subspecies which correspond to pathogenicity and host range characteristics.(ABSTRACT TRUNCATED AT 250 WORDS)
Wolschendorf, Frank; Mahfoud, Maysa; Niederweis, Michael
Phosphorus is an essential nutrient, but how phosphates cross the mycobacterial cell wall is unknown. Phosphatase activity in whole cells of Mycobacterium smegmatis was significantly lower than that in lysed cells, indicating that access to the substrate was restricted. The loss of the outer membrane (OM) porin MspA also reduced the phosphatase activity in whole cells compared to that in lysed cells. A similar result was obtained for M. smegmatis that overexpressed endogenous alkaline phosphatase, indicating that PhoA is not a surface protein, contrary to a previous report. The uptake of phosphate by a mutant lacking the porins MspA and MspC was twofold lower than that by wild-type M. smegmatis. Strikingly, the loss of these porins resulted in a severe growth defect of M. smegmatis on low-phosphate plates. We concluded that the OM of M. smegmatis represents a permeability barrier for phosphates and that Msp porins are the only OM channels for the diffusion of phosphate in M. smegmatis. However, phosphate diffusion through Msp pores is rather inefficient as shown by the 10-fold lower permeability of M. smegmatis for phosphate compared to that for glucose. This is likely due to the negative charges in the constriction zone of Msp porins. The phosphatase activity in whole cells of Mycobacterium bovis BCG was significantly less than that in lysed cells, indicating a similar uptake pathway for phosphates in slow-growing mycobacteria. However, porins that could mediate the diffusion of phosphates across the OM of M. bovis BCG and Mycobacterium tuberculosis are unknown. PMID:17209034
Bouricha, Mehdi; Castan, Bernard; Duchene-Parisi, Elisabeth; Drancourt, Michel
A 19-year-old man presented with a 1.5-cm nodule on the first dorsal metacarpal ray. The patient denied having contact with fish tanks or fish, but recalled handling many reptiles without gloves in the vivarium where he worked. A culture of a skin biopsy specimen yielded Mycobacterium marinum. The clinical outcome was favourable after a 2-week course of intramuscular gentamicin (180 mg daily) combined with a 6-week course of oral clarithromycin (500 mg twice a day). Doctors should be aware that vivariums, in addition to fish tanks, can be sources of M. marinum exposure.
We report two series of novel cephalosporins that are bactericidal to Mycobacterium tuberculosis alone of the pathogens tested, which only kill M. tuberculosis when its replication is halted by conditions resembling those believed to pertain in the host, and whose bactericidal activity is not dependent upon or enhanced by clavulanate, a β-lactamase inhibitor. The two classes of cephalosporins bear an ester or alternatively an oxadiazole isostere at C-2 of the cephalosporin ring system, a position that is almost exclusively a carboxylic acid in clinically used agents in the class. Representatives of the series kill M. tuberculosis within macrophages without toxicity to the macrophages or other mammalian cells. PMID:27144688
Gold, Ben; Smith, Robert; Nguyen, Quyen; Roberts, Julia; Ling, Yan; Lopez Quezada, Landys; Somersan, Selin; Warrier, Thulasi; Little, David; Pingle, Maneesh; Zhang, David; Ballinger, Elaine; Zimmerman, Matthew; Dartois, Véronique; Hanson, Paul; Mitscher, Lester A; Porubsky, Patrick; Rogers, Steven; Schoenen, Frank J; Nathan, Carl; Aubé, Jeffrey
We report two series of novel cephalosporins that are bactericidal to Mycobacterium tuberculosis alone of the pathogens tested, which only kill M. tuberculosis when its replication is halted by conditions resembling those believed to pertain in the host, and whose bactericidal activity is not dependent upon or enhanced by clavulanate, a β-lactamase inhibitor. The two classes of cephalosporins bear an ester or alternatively an oxadiazole isostere at C-2 of the cephalosporin ring system, a position that is almost exclusively a carboxylic acid in clinically used agents in the class. Representatives of the series kill M. tuberculosis within macrophages without toxicity to the macrophages or other mammalian cells.
Ferraris, Davide M; Spallek, Ralf; Oehlmann, Wulf; Singh, Mahavir; Rizzi, Menico
The tricarboxylic acid (TCA) cycle is a central metabolic pathway of all aerobic organisms and is responsible for the synthesis of many important precursors and molecules. TCA cycle plays a key role in the metabolism of Mycobacterium tuberculosis and is involved in the adaptation process of the bacteria to the host immune response. We present here the first crystal structures of M. tuberculosis malate dehydrogenase and citrate synthase, two consecutive enzymes of the TCA, at 2.6 Å and 1.5 Å resolution, respectively. General analogies and local differences with the previously reported homologous protein structures are described. © 2014 Wiley Periodicals, Inc.
Early, Julie V.; Casey, Allen; Martinez-Grau, Maria Angeles; Gonzalez Valcarcel, Isabel C.; Vieth, Michal; Ollinger, Juliane; Bailey, Mai Ann; Alling, Torey; Files, Megan; Ovechkina, Yulia
Mycobacterium tuberculosis is a global pathogen of huge importance which can adapt to several host niche environments in which carbon source availability is likely to vary. We developed and ran a phenotypic screen using butyrate as the sole carbon source to be more reflective of the host lung environment. We screened a library of ∼87,000 small compounds and identified compounds which demonstrated good antitubercular activity against M. tuberculosis grown with butyrate but not with glucose as the carbon source. Among the hits, we identified an oxadiazole series (six compounds) which had specific activity against M. tuberculosis but which lacked cytotoxicity against mammalian cells. PMID:27044545
Mycobacterium tuberculosis is a highly efficient pathogen, killing millions of infected people annually. The capacity of M. tuberculosis to survive and cause disease is strongly correlated to their ability to escape immune defense mechanisms. In particular, M. tuberculosis has the remarkable capacity to survive within the hostile environment of the macrophage. Understanding M. tuberculosis virulence strategies will not only define novel targets for drug development but will also help to uncover previously unknown signaling pathways related to the host's response to M. tuberculosis infection.
Shin, N S; Kwon, S W; Han, D H; Bai, G H; Yoon, J; Cheon, D S; Son, Y S; Ahn, K; Chae, C; Lee, Y S
A respiratory disorder was noted in a 5-year-old female orangutan kept in the Yongin Farmland. Radiographically, multiple radiodense foci ranging from 2 to 6 mm diameter were seen throughout the lung lobes. Grossly, the thoracic cavity revealed a firm texture and grayish-pink discoloration of the left apical lung lobe. Histopathologically, multifocal areas of granulomatous pneumonia present the right and left apical lung lobes. Both primers from IS1081 and IS6110 targeting 196 bp and 245 bp respectively were used in polymerase chain reaction, Mycobacterium tuberculosis was isolated from liver and confirmed by polymerase chain reaction.
Dietrich, U; Arnold, P; Guscetti, F; Pfyffer, G E; Spiess, B
Disseminated mycobacterial disease was diagnosed in an eight-year-old domestic shorthaired cat, with involvement of the skin, lungs, lymph nodes and one eye. Mycobacterium simiae was cultured from skin biopsies on solid agar and in liquid media. This organism is known to cause pulmonary, cutaneous or disseminated infection in human patients with acquired immunodeficiency syndrome but has never been encountered as a pathogen in companion animals. Combination treatment with rifampicin, enrofloxacin and clarithromycin resulted in complete clinical remission within six months, with no side effects. No recurrence was observed in a 22-month follow-up period.
Prados-Rosales, Rafael; Weinrick, Brian C.; Piqué, Daniel G.; Jacobs, William R.; Casadevall, Arturo
Mycobacterium tuberculosis releases membrane vesicles packed with molecules that can modulate the immune response. Because environmental conditions often influence the production and content of bacterial vesicles, this study examined M. tuberculosis microvesicles released under iron limitation, a common condition faced by pathogens inside the host. The findings indicate that M. tuberculosis increases microvesicle production in response to iron restriction and that these microvesicles contain mycobactin, which can serve as an iron donor and supports replication of iron-starved mycobacteria. Consequently, the results revealed a role of microvesicles in iron acquisition in M. tuberculosis, which can be critical for survival in the host. PMID:24415729
Honore, N; Cole, S T
Rifampin is currently the most potent drug used in leprosy control programs. We show that the rifampin resistance which emerged in nine patients with lepromatous leprosy, who had received rifampin monotherapy, stemmed from mutations in the rpoB gene, which encodes the beta subunit of RNA polymerase of Mycobacterium leprae. In eight cases missense mutations were found to affect a serine residue, Ser-425, while in the remaining mutant a small insertion was found close to this site. These findings will be of use for the development of a rapid screening procedure, involving the polymerase chain reaction, for monitoring the emergence of rifampin-resistant M. leprae strains. Images PMID:8460911
Punjabi, Chitra D; Perloff, Sarah R; Zuckerman, Jerry M
Patients with tuberculosis (TB) pose a risk to other patients and health care workers, and outbreaks in health care settings occur when appropriate infection control measures are not used. In this article, we discuss strategies to prevent transmission of Mycobacterium tuberculosis within health care settings. All health care facilities should have an operational TB infection control plan that emphasizes the use of a hierarchy of controls (administrative, environmental, and personal respiratory protection). We also discuss resources available to clinicians who work in the prevention and investigation of nosocomial transmission of M tuberculosis. Copyright © 2016 Elsevier Inc. All rights reserved.
Schefzyk, M; Richter, E; Röhrbein, J H; Schaefer, T; Wedi, B; Raap, U
Cutaneous infections with Mycobacterium marinum are rare. They also are known as swimming pool or fish tank granulomas. Often the history of contact with contaminated water associated with microtrauma of the upper extremities leads to the correct diagnosis. Since chlorination of swimming pools has become standard, cases of swimming pool granuloma have become rare. Contact with fish tanks now is the most common route of infection. Positive culture of skin biopsy leads to the correct diagnosis. Moxifloxacin in combination with other antibiotics is often effective.
Chen, Chung-Hua; Lin, Jesun; Lin, Jen-Shiou; Chen, Yu-Min
We present the case of a 49-year-old man, who developed Mycobacterium abscessus complex (M. abscessus complex) bacteremia and prostatitis after prostate biopsy. The patient was successfully treated with amikacin with imipenem-cilastatin with clarithromycin. Infections caused by M. abscessus complex have been increasingly described as a complication associated with many invasive procedures. Invasive procedures might have contributed to the occurrence of the M. abscessus complex. Although M. abscessus complex infection is difficult to diagnose and treat, we should pay more attention to this kind of infection, and the correct treatment strategy will be achieved by physicians.
de Prince, Karina Andrade; Sordi, Renata; Pavan, Fernando Rogério; Barreto Santos, Adolfo Carlos; Araujo, Angela R.; Leite, Sergio R.A.; Leite, Clarice Q. F.
Our purpose was to determine the anti-Mycobacterium tuberculosis activity of the metabolites produced by the endophitic fungus Phomopsis stipata (Lib.) B. Sutton, (Diaporthaceae), cultivated in different media. The antimycobacterial activity was assessed through the Resazurin Microtiter Assay (REMA) and the cytotoxicity test performed on macrophage cell line. The extracts derived from fungi grown on Corn Medium and Potato Dextrose Broth presented the smallest values of Minimum Inhibitory Concentration (MIC) and low cytotoxicity, which implies a high selectivity index. This is the first report on the chemical composition and antitubercular activity of metabolites of P. stipata, as well as the influence of culture medium on these properties. PMID:24031821
Cosivi, O.; Grange, J. M.; Daborn, C. J.; Raviglione, M. C.; Fujikura, T.; Cousins, D.; Robinson, R. A.; Huchzermeyer, H. F.; de Kantor, I.; Meslin, F. X.
The World Health Organization (WHO) estimates that human tuberculosis (TB) incidence and deaths for 1990 to 1999 will be 88 million and 30 million, respectively, with most cases in developing countries. Zoonotic TB (caused by Mycobacterium bovis) is present in animals in most developing countries where surveillance and control activities are often inadequate or unavailable; therefore, many epidemiologic and public health aspects of infection remain largely unknown. We review available information on zoonotic TB in developing countries, analyze risk factors that may play a role in the disease, review recent WHO activities, and recommend actions to assess the magnitude of the problem and control the disease in humans and animals. PMID:9452399
Eddyani, M; Portaels, F
Bone infection and metastatic spread in cases of Buruli ulcer imply that Mycobacterium ulcerans is able to survive and multiply at 37 degrees C. This study investigated the survival at 37 degrees C of M. ulcerans isolates from diverse geographical and clinical sources. Although the viability of all isolates decreased after a few days at 37 degrees C, viable bacilli remained after 13 days at 37 degrees C in most instances. African isolates of M. ulcerans were more thermotolerant than isolates from temperate regions. Isolates from skin and bone lesions of the same patients showed no difference in thermotolerance.
Das, Maumita; Sumana, Gajjala; Nagarajan, R.; Malhotra, B. D.
Nanostructured zirconium oxide (ZrO2) film (particle size˜35 nm), electrochemically deposited onto gold(Au) surface, has been used to immobilize 21-mer oligonucleotide probe (ssDNA) specific to Mycobacterium tuberculosis by utilizing affinity between oxygen atom of phosphoric group and zirconium to fabricate DNA biosensor. This DNA-ZrO2/Au bioelectrode, characterized using x-ray diffraction, Fourier transform infrared spectroscopy, cyclic voltammetry, and scanning electron microscopy techniques, can be used for early and rapid diagnosis of M. tuberculosis with detection limit of 0.065 ng/μL within 60s.
Brown-Elliott, Barbara A; Philley, Julie V; Griffith, David E; Thakkar, Foram; Wallace, Richard J
We performed bedaquiline broth microdilution susceptibility testing using Clinical and Laboratory Standards Institute (CLSI) guidelines on 103 respiratory isolates of Mycobacterium avium complex (MAC), including multidrug-resistant isolates. Approximately 90% of isolates had bedaquiline MICs of ≤0.008 μg/ml, and 102/103 isolates had MICs of ≤0.015 μg/ml. Bedaquiline has excellent potential for use in patients with MAC infections, although for reasons of its metabolism by the cytochrome P450 system, it should not be given with rifampin.
Patel, Shivani S; Tavana, M Lance; Boger, M Sean; Win, Soe Soe; Rimawi, Bassam H
Cutaneous infections caused by Mycobacterium marinum have been attributed to aquarium or fish exposure after a break in the skin barrier. In most instances, the upper limbs and fingers account for a majority of the infection sites. While previous cases of necrotizing soft tissue infections related to M. marinum have been documented, the importance of our presenting case is to illustrate the aggressive nature of M. marinum resulting in a persistent necrotizing soft tissue infection of a finger that required multiple aggressive wound debridements, followed by an amputation of the affected extremity, in order to hasten recovery.
Patel, Shivani S.; Tavana, M. Lance; Boger, M. Sean; Win, Soe Soe; Rimawi, Bassam H.
Cutaneous infections caused by Mycobacterium marinum have been attributed to aquarium or fish exposure after a break in the skin barrier. In most instances, the upper limbs and fingers account for a majority of the infection sites. While previous cases of necrotizing soft tissue infections related to M. marinum have been documented, the importance of our presenting case is to illustrate the aggressive nature of M. marinum resulting in a persistent necrotizing soft tissue infection of a finger that required multiple aggressive wound debridements, followed by an amputation of the affected extremity, in order to hasten recovery. PMID:25506004
Huynh, M; Pingret, J-L; Nicolier, A
A 1-year-old neutered male chinchilla (Chinchilla lanigera) was presented with emaciation and a 1-month history of progressive weight loss. The animal was bright and responsive on clinical examination, but had poor body condition. Serum biochemical analysis revealed elevated alanine amino transferase and alkaline phosphatase. Ultrasound examination was unremarkable. Thoracic radiography showed changes consistent with bullous emphysema and severe pneumonia. Antibiotic therapy was initiated, but the chinchilla died 6 weeks later. Necropsy examination revealed granulomatous lesions in the lungs and liver. Numerous acid-fast bacilli were present in the cytoplasm of macrophages. Sequencing of genetic material isolated from fixed tissue classified the pathogen as Mycobacterium genavense.
Toy, Brian R; Frank, Paul Jarrod
Illicit soft-tissue augmentation performed in New York City resulted in an outbreak of Mycobacterium abscessus infection in 2002. To report two cases of women who developed tender, subcutaneous nodules of the face and buttocks after illicit soft-tissue augmentation with a hyaluronic acid derivative. Two case reports are presented, and the literature is reviewed. Empiric treatment with clarithromycin (for M. abscessus infection) and prednisone (for foreign body reaction) resulted in clearance of lesions. Contaminated or impure material used for soft-tissue augmentation can result in a clustered outbreak of infection or foreign body reaction.
Callen, Erin C; Kessler, Tiffany L
Mycobacterium fortuitum, a rapidly growing atypical mycobacteria, is commonly found in soil and water. This organism is most often known to cause skin, bone, and soft tissue infections associated with local trauma, surgical procedures, and in patients with immunodeficiency. Nosocomial infections associated with a variety of contaminated devices and equipment have also been widely documented. This report presents the first cases of M. fortuitum infection following laparoscopic gastric banding procedures. Both patients had complicated clinical courses necessitating removal of their banding devices and long-term antibiotic therapy.
Cruz, Andrea T; Antekeier, Shannon B
We present the case of a 10-year-old girl with Mycobacterium fortuitum osteomyelitis following a plantar puncture wound with vegetative material. Nontuberculous mycobacterial (NTM) skin and soft tissue infections are well described in immunocompromised populations. However, NTM infection can also be seen in healthy hosts following direct inoculation. Magnetic resonance imaging examination demonstrated multifocal midfoot and metatarsal osteomyelitis. Surgical exploration revealed caseation necrosis and a chronic draining sinus tract. Combined surgical debridement and medical therapy resulted in clinical cure. A high index of suspicion and adequate collection and handling of surgical specimens facilitate the diagnosis and treatment of NTM skin and soft tissue infections.
Ouellet, Hugues; Johnston, Jonathan B.; Ortiz de Montellano, Paul R.
Mycobacterium tuberculosis (Mtb) is an intracellular pathogen that infects 10 million worldwide and kills 2 million people every year. The uptake and utilization of nutrients by Mtb within the host cell is still poorly understood, although lipids play an important role in Mtb persistence. The recent identification of a large regulon of cholesterol catabolic genes suggests that Mtb can use host sterol for infection and persistence. In this review, we report on recent progress in elucidation of the Mtb cholesterol catabolic reactions and their potential utility as targets for tuberculosis therapeutic agents. PMID:21924910
Seo, Min-Goo; Ouh, In-Ohk; Kim, Munki; Lee, Jienny; Kim, Young-Hoan; Do, Jae-Cheul; Kwak, Dongmi
Tuberculosis, a chronic progressive disease, has been reported in bovine, swine, and primate species. Here, we report the first case of Mycobacterium tuberculosis infection in a Korean wild boar ( Sus scrofa coreanus). The owners this domesticated boar brought it to the Gyeongbuk Veterinary Service Laboratory in Korea after it was found dead and severely emaciated. Demarcated yellowish white nodules were found around the larynx and retropharyngeal lymph node during necropsy. The lungs had diffuse fibrinous pleuritis, severe congestion, and scattered nodules. More nodules were found in the spleen. Tuberculosis is characterized by massive macrophage infiltration and central caseous necrosis; both characteristics were found in the lungs. Histopathologic examination revealed that the alveolar lumen had marked fibrosis and exudates. Examination of the fluid revealed extensive macrophage permeation. To confirm a Mycobacterium infection, PCR was performed using two primer sets specific to the rpoB gene of Mycobacterium; Mycobacterium was detected in the lungs and spleen. To identify the species of Mycobacterium, immunohistochemical evaluation was performed using antibodies against Mycobacterium tuberculosis and Mycobacterium bovis . The results revealed immunoreactivity against M. tuberculosis but not against M. bovis . The consumption of undercooked or raw meat from game animals may expose humans and other animals to sylvatic infection. Consequently, Koreans who ingest wild boar may be at risk of a tuberculosis infection. To reduce the risk of foodborne infection and maintain public health, continuous monitoring and control strategies are required.
Description of Mycobacterium chelonae subsp. bovis subsp. nov., isolated from cattle (Bos taurus coreanae), emended description of Mycobacterium chelonae and creation of Mycobacterium chelonae subsp. chelonae subsp. nov.
Kim, Byoung-Jun; Kim, Ga-Na; Kim, Bo-Ram; Jeon, Che Ok; Jeong, Joseph; Lee, Seon Ho; Lim, Ji-Hun; Lee, Seung-Heon; Kim, Chang Ki; Kook, Yoon-Hoh; Kim, Bum-Joon
Three rapidly growing mycobacterial strains, QIA-37T, QIA-40 and QIA-41, were isolated from the lymph nodes of three separate Korean native cattle, Hanwoo (Bos taurus coreanae). These strains were previously shown to be phylogenetically distinct but closely related to Mycobacterium chelonae ATCC 35752T by taxonomic approaches targeting three genes (16S rRNA, hsp6 and rpoB) and were further characterized using a polyphasic approach in this study. The 16S rRNA gene sequences of all three strains showed 99.7 % sequence similarity with that of the M. chelonae type strain. A multilocus sequence typing analysis targeting 10 housekeeping genes, including hsp65 and rpoB, revealed a phylogenetic cluster of these strains with M. chelonae. DNA-DNA hybridization values of 78.2 % between QIA-37T and M. chelonae indicated that it belongs to M. chelonae but is a novel subspecies distinct from M. chelonae. Phylogenetic analysis based on whole-genome sequences revealed a 95.44±0.06 % average nucleotide identity (ANI) value with M. chelonae, slightly higher than the 95.0 % ANI criterion for determining a novel species. In addition, distinct phenotypic characteristics such as positive growth at 37 °C, at which temperature M. chelonae does not grow, further support the taxonomic status of these strains as representatives of a novel subspecies of M. chelonae. Therefore, we propose an emended description of Mycobacterium chelonae, and descriptions of M. chelonae subsp. chelonae subsp. nov. and M. chelonae subsp. bovis subsp. nov. are presented; strains ATCC 35752T(=CCUG 47445T=CIP 104535T=DSM 43804T=JCM 6388T=NCTC 946T) and QIA-37T (=KCTC 39630T=JCM 30986T) are the type strains of the two novel subspecies.
Molina, Elena; Elguezabal, Natalia; Pérez, Valentín; Garrido, Joseba M.
Mycobacterium tuberculosis complex, Mycobacterium avium, and many other nontuberculous mycobacteria are worldwide distributed microorganisms of major medical and veterinary importance. Considering the growing epidemiologic significance of wildlife-livestock-human interrelation, developing rapid detection tools of high specificity and sensitivity is vital to assess their presence and accelerate the process of diagnosing mycobacteriosis. Here we describe the development and evaluation of a novel tetraplex real-time PCR for simultaneous detection of Mycobacterium genus, M. avium subspecies, and M. tuberculosis complex in an internally monitored single assay. The method was evaluated using DNA from mycobacterial (n = 38) and nonmycobacterial (n = 28) strains, tissues spiked with different CFU amounts of three mycobacterial species (n = 57), archival clinical samples (n = 233), and strains isolated from various hosts (n = 147). The minimum detectable DNA amount per reaction was 50 fg for M. bovis BCG and M. kansasii and 5 fg for M. avium subsp. hominissuis. When spiked samples were analyzed, the method consistently detected as few as 100 to 1,000 mycobacterial CFU per gram. The sensitivity and specificity values for the panel of clinical samples were 97.5 and 100% using a verified culture-based method as the reference method. The assays performed on clinical isolates confirmed these results. This PCR was able to identify M. avium and M. tuberculosis complex in the same sample in one reaction. In conclusion, the tetraplex real-time PCR we designed represents a highly specific and sensitive tool for the detection and identification of mycobacteria in routine laboratory diagnosis with potential additional uses. PMID:25588660
Sevilla, Iker A; Molina, Elena; Elguezabal, Natalia; Pérez, Valentín; Garrido, Joseba M; Juste, Ramón A
Mycobacterium tuberculosis complex, Mycobacterium avium, and many other nontuberculous mycobacteria are worldwide distributed microorganisms of major medical and veterinary importance. Considering the growing epidemiologic significance of wildlife-livestock-human interrelation, developing rapid detection tools of high specificity and sensitivity is vital to assess their presence and accelerate the process of diagnosing mycobacteriosis. Here we describe the development and evaluation of a novel tetraplex real-time PCR for simultaneous detection of Mycobacterium genus, M. avium subspecies, and M. tuberculosis complex in an internally monitored single assay. The method was evaluated using DNA from mycobacterial (n = 38) and nonmycobacterial (n = 28) strains, tissues spiked with different CFU amounts of three mycobacterial species (n = 57), archival clinical samples (n = 233), and strains isolated from various hosts (n = 147). The minimum detectable DNA amount per reaction was 50 fg for M. bovis BCG and M. kansasii and 5 fg for M. avium subsp. hominissuis. When spiked samples were analyzed, the method consistently detected as few as 100 to 1,000 mycobacterial CFU per gram. The sensitivity and specificity values for the panel of clinical samples were 97.5 and 100% using a verified culture-based method as the reference method. The assays performed on clinical isolates confirmed these results. This PCR was able to identify M. avium and M. tuberculosis complex in the same sample in one reaction. In conclusion, the tetraplex real-time PCR we designed represents a highly specific and sensitive tool for the detection and identification of mycobacteria in routine laboratory diagnosis with potential additional uses.
Turk, Tarek; Almahmoud, Mohamed Faher; Raslan, Khulood
Mycobacterium kansasii is a slow growing acid-fast non-tuberculosis mycobacterium. It most commonly causes pulmonary disease with tuberculosis-like manifestations. Mycobacterium kansasii-induced skin and soft tissue infections (SSTIs) are very uncommon, especially in the absence of obvious risk factors. In this report, we present a rare case of M. kansasii-associated SSTI complicated by tendonitis and osteomyelitis in an immunocompetent patient. This case highlights the importance of considering non-tuberculosis mycobacteria while investigating chronic, relapsing, non-healing SSTIs and osteomyelitis. Proper pharmacotherapy, along with surgical debridement, is the optimal management to avoid relapse and the production of resistant species. PMID:28031850
Ando, Masaru; Mukai, Yutaka; Ushijima, Ryo-ichi; Shioyama, Yoshiyuki; Umeki, Kenji; Okada, Fumito; Nureki, Shin-ichi; Mimata, Hiromitsu; Kadota, Jun-ichi
Fluorodeoxyglucose (FDG)-positron emission tomography with computed tomography (FDG-PET/CT) is useful in disease monitoring of malignancies after therapy, while an FDG uptake may also be present in benign diseases. We herein demonstrate a case of disseminated Mycobacterium tuberculosis mimicking systemic metastasis of prostate cancer. This case highlights that clinicians should consider Mycobacterium tuberculosis in patients with prostate cancer who demonstrate multifocal FDG uptakes masquerading as metastasis, even when the chest photographs reveal a normal appearance and a sputum examination demonstrates negative results. An invasive surgical biopsy may be required and a pathological analysis would be critical in the diagnosis of Mycobacterium tuberculosis. PMID:27853089
Lee, Hae Young; Cho, Seong Ho; Kim, Hyun Su; Moon, Jeong Min; Lee, Sangho; Kim, Jong In
An 81-year-old male patient presented with complaint of a pulsating neck mass. The patient had a previous history of cervical lymphadenopathy by non-tuberculous mycobacterium infection. Rapid growth of the mass on admission and contrast enhanced computed tomography of the neck resulted in a diagnosis of non-tuberculous mycobacterium induced pseudoaneurysm. The patient underwent emergency open repair of the pseudoaneurysm. Pseudoaneurysm of the common carotid artery is regularly reported, but here we report a rare case of non-tuberculous mycobacterium induced pseudoaneurysm of the common carotid artery. PMID:27965926
Molina-Torres, Carmen A.; Ocampo-Candiani, Jorge; Rendón, Adrian; Pucci, Michael J.; Vera-Cabrera, Lucio
In this work, we describe the activity of ACH-702 against clinical isolates of Mycobacterium tuberculosis and six different nontuberculous mycobacteria. The MIC50 and MIC90 of both susceptible and drug-resistant M. tuberculosis strains tested were 0.0625 and 0.125 μg/ml, respectively. The MIC50 and MIC90 values for Mycobacterium fortuitum isolates were 0.0625 μg/ml in both cases; Mycobacterium avium complex isolates showed MIC50 and MIC90 values of 0.25 and 4 μg/ml, respectively. PMID:20231398
Pedrosa, Margarita; Soriano, Alex; Zboromyrska, Yuliya; Tudo, Griselda; Garcia, Sebastian; Pomes, Jaime
Mycobacterium marinum is an atypical mycobacterium that usually causes a solitary nodule on the hand (“fish tank granuloma”) or less commonly, secondary erythematous channels and nodules spread along lymphatic drainage of the extremity, mimicking sporothricoid skin lesions of nodular lymphangitis. This report presents a case of this rare entity, a nodular lymphangitis caused by Mycobacterium marinum. Multidetector computed tomography (MDCT) imaging was very useful in determining the morphology (cellulitis with a few small subcutaneous nodules and channels) and the extension of the lesion. PMID:24778804
La demostración se basa en el hecho de que las integrales del problema de los N-cuerpos admiten componentes en el campo complejo según las raíces n-ésimas de la unidad. Definida la matriz unitaria correspondiente, la fórmula de Cayley permite transformar la matriz unitaria en una matriz hermitiana. Utilizando como parámetros los cosenos direccionales de un sistema de coordenadas orbitales referidos a un sistema de referencia fijo, puede construirse, utilizando el operador hermitiano antes definido, una forma cuadrática cuyas raíces mínima y máxima definen las cotas respectivas de los movimientos de los mencionados cosenos direccionales.
Gygli, Sebastian M; Borrell, Sonia; Trauner, Andrej; Gagneux, Sebastien
Antibiotic-resistant Mycobacterium tuberculosis strains are threatening progress in containing the global tuberculosis epidemic. Mycobacterium tuberculosis is intrinsically resistant to many antibiotics, limiting the number of compounds available for treatment. This intrinsic resistance is due to a number of mechanisms including a thick, waxy, hydrophobic cell envelope and the presence of drug degrading and modifying enzymes. Resistance to the drugs which are active against M. tuberculosis is, in the absence of horizontally transferred resistance determinants, conferred by chromosomal mutations. These chromosomal mutations may confer drug resistance via modification or overexpression of the drug target, as well as by prevention of prodrug activation. Drug resistance mutations may have pleiotropic effects leading to a reduction in the bacterium's fitness, quantifiable e.g. by a reduction in the in vitro growth rate. Secondary so-called compensatory mutations, not involved in conferring resistance, can ameliorate the fitness cost by interacting epistatically with the resistance mutation. Although the genetic diversity of M. tuberculosis is low compared to other pathogenic bacteria, the strain genetic background has been demonstrated to influence multiple aspects in the evolution of drug resistance. The rate of resistance evolution and the fitness costs of drug resistance mutations may vary as a function of the genetic background.
Cadmus, S I B; Adesokan, H K; Okker, M; Jahans, K
To ascertain the cause of tuberculous-like lesions in pigs slaughtered in a local abattoir in Ibadan (south-western Nigeria), a total of 516 pigs were inspected over a period of four months, 18 of which had gross lesions suggestive of tuberculosis at post-mortem. Mycobacterial culture and molecular typing (GenoType Mycobacterium CM [Common Mycobacteria] assay) analysis were used to identify and confirm the mycobacteria species responsible for these lesions. Results show that 2.3% (12/516) of the animals screened were infected with mycobacteria; Mycobacterium fortuitum was confirmed in 33.3% (4/12) of these cases. As far as the authors are aware, this is the first report confirming the isolation of M. fortuitum in slaughtered pigs in Nigeria. There is a need to improve on necessary preventive and control measures that will reduce potential sources of mycobacterial infections in pig-rearing herds. These infections may also have public health implications, especially to workers in the pig industry.
Lindeboom, Jerome A.; Bruijnesteijn van Coppenraet, Lesla E. S.; van Soolingen, Dick; Prins, Jan M.; Kuijper, Eduard J.
Summary: Mycobacterium haemophilum is a slowly growing acid-fast bacillus (AFB) belonging to the group of nontuberculous mycobacteria (NTM) frequently found in environmental habitats, which can colonize and occasionally infect humans and animals. Several findings suggest that water reservoirs are a likely source of M. haemophilum infections. M. haemophilum causes mainly ulcerating skin infections and arthritis in persons who are severely immunocompromised. Disseminated and pulmonary infections occasionally occur. The second at-risk group is otherwise healthy children, who typically develop cervical and perihilar lymphadenitis. A full diagnostic regimen for the optimal detection of M. haemophilum includes acid-fast staining, culturing at two temperatures with iron-supplemented media, and molecular detection. The most preferable molecular assay is a real-time PCR targeting an M. haemophilum-specific internal transcribed spacer (ITS), but another approach is the application of a generic PCR for a mycobacterium-specific fragment with subsequent sequencing to identify M. haemophilum. No standard treatment guidelines are available, but published literature agrees that immunocompromised patients should be treated with multiple antibiotics, tailored to the disease presentation and underlying degree of immune suppression. The outcome of M. haemophilum cervicofacial lymphadenitis in immunocompetent patients favors surgical intervention rather than antibiotic treatment. PMID:21976605
Soetaert, Karine; Vluggen, Christelle; André, Emmanuel; Vanhoof, Raymond; Vanfleteren, Brigitte; Mathys, Vanessa
Mycobacterium chimaera arouses an increasing public health concern, as this non-tuberculous mycobacterium (NTM) has recently been associated with life-threatening cardiac infections. M. chimaera and Mycobacteriumintracellulare are genetically very close but recently appeared to present different epidemiological and clinical significance. Therefore, it has become important for laboratories to use adequate techniques allowing precise species identification. To date, most commercially available laboratory assays cannot distinguish them and erroneously identify M. chimaera as M. intracellulare. We performed a re-analysis of the 149 M. intracellulare strains received by the Belgian National Reference Laboratory using 16S rRNA gene sequencing, representing 25 % of all NTM collected in 2015. We found that M. chimaera represents the majority (n=94, 63 %) of the previous M. intracellulare. This study reports the large presence of M. intracellulare/chimaera among Belgian patients infected by an NTM and the predominance of the species M. chimaera among this group. This study also stresses the public health importance of M. chimaera and demonstrates the inability of commonly used laboratory techniques to correctly diagnose these infections.
Bañuls, Anne-Laure; Sanou, Adama; Anh, Nguyen Thi Van; Godreuil, Sylvain
Some species of the Mycobacterium tuberculosis complex (MTBC), particularly Mycobacterium tuberculosis, which causes human tuberculosis (TB), are the first cause of death linked to a single pathogen worldwide. In the last decades, evolutionary studies have much improved our knowledge on MTBC history and have highlighted its long co-evolution with humans. Its ability to remain latent in humans, the extraordinary proportion of asymptomatic carriers (one-third of the entire human population), the deadly epidemics and the observed increasing level of resistance to antibiotics are proof of its evolutionary success. Many MTBC molecular signatures show not only that these bacteria are a model of adaptation to humans but also that they have influenced human evolution. Owing to the unbalance between the number of asymptomatic carriers and the number of patients with active TB, some authors suggest that infection by MTBC could have a protective role against active TB disease and also against other pathologies. However, it would be inappropriate to consider these infectious pathogens as commensals or symbionts, given the level of morbidity and mortality caused by TB.
Anuchin, Aleksey M; Mulyukin, Andrey L; Suzina, Natalya E; Duda, Vitaly I; El-Registan, Galina I; Kaprelyants, Arseny S
Cultivation of Mycobacterium smegmatis cells in a nitrogen-limited minimal medium (SR-1) followed by prolonged storage at room temperature without shaking resulted in the gradual accumulation of morphologically distinct ovoid forms characterized by (i) low metabolic activity; (ii) elevated resistance to antibiotics and to heat treatment; and (iii) inability to produce colonies on standard agar plates (non-platable cells). Detailed microscopic examination confirmed that ovoid cells possessed an intact cell envelope, specific fine structure and large electron-transparent bodies in the cytoplasm. Cell staining with Nile red and analysis of the lipid content by TLC revealed the presence of significant amounts of apolar lipids in these bodies. The ovoid forms could be stored for significant periods (up to 5 months) and resuscitated afterwards in a modified Sauton's medium. Importantly, resuscitation of ovoid cells was accompanied by their transformation into the typical rod-shaped cells. We suggest that the observed ovoid cells represent dormant forms, resembling morphologically distinct cells of Mycobacterium tuberculosis previously isolated from tuberculosis patients and infected animals.
Nogueira, Christiane L; de Almeida, Luiz G P; Menendez, Maria C; Garcia, Maria J; Digiampietri, Luciano A; Chimara, Erica; Cnockaert, Margo; Palomino, Juan C; Portaels, Françoise; Martin, Anandi; Vandamme, Peter; Leão, Sylvia C
Isolates of the Mycobacterium chelonae-M. abscessus complex are subdivided into four clusters (CHI to CHIV) in the INNO-LiPA® Mycobacterium spp DNA strip assay. A considerable phenotypic variability was observed among isolates of the CHII cluster. In this study, we examined the diversity of 26 CHII cluster isolates by phenotypic analysis, drug susceptibility testing, whole genome sequencing and single-gene analysis. Pairwise genome comparisons were performed using several approaches, including average nucleotide identity (ANI) and genome-to-genome distance (GGD) among others. Based on ANI and GGD the isolates were identified as M. chelonae (14 isolates), M. franklinii (2 isolates) and M. salmoniphium (1 isolate). The remaining 9 isolates were subdivided into three novel putative genomospecies. Phenotypic analyses including drug susceptibility testing, as well as whole genome comparison by TETRA and delta differences, were not helpful in separating the groups revealed by ANI and GGD. The analysis of standard four conserved genomic regions showed that rpoB alone and the concatenated sequences clearly distinguished the taxonomic groups delimited by whole genome analyses. In conclusion, the CHII INNO-LiPa is not a homogeneous cluster; on the contrary, it is composed of closely related different species belonging to the M. chelonae-M. abscessus complex and also several unidentified isolates. The detection of these isolates, putatively novel species, indicates a wider inner variability than the presently known in this complex.
Nogueira, Christiane L.; de Almeida, Luiz G. P.; Menendez, Maria C.; Garcia, Maria J.; Digiampietri, Luciano A.; Chimara, Erica; Cnockaert, Margo; Palomino, Juan C.; Portaels, Françoise; Martin, Anandi; Vandamme, Peter; Leão, Sylvia C.
Isolates of the Mycobacterium chelonae-M. abscessus complex are subdivided into four clusters (CHI to CHIV) in the INNO-LiPA® Mycobacterium spp DNA strip assay. A considerable phenotypic variability was observed among isolates of the CHII cluster. In this study, we examined the diversity of 26 CHII cluster isolates by phenotypic analysis, drug susceptibility testing, whole genome sequencing and single-gene analysis. Pairwise genome comparisons were performed using several approaches, including average nucleotide identity (ANI) and genome-to-genome distance (GGD) among others. Based on ANI and GGD the isolates were identified as M. chelonae (14 isolates), M. franklinii (2 isolates) and M. salmoniphium (1 isolate). The remaining 9 isolates were subdivided into three novel putative genomospecies. Phenotypic analyses including drug susceptibility testing, as well as whole genome comparison by TETRA and delta differences, were not helpful in separating the groups revealed by ANI and GGD. The analysis of standard four conserved genomic regions showed that rpoB alone and the concatenated sequences clearly distinguished the taxonomic groups delimited by whole genome analyses. In conclusion, the CHII INNO-LiPa is not a homogeneous cluster; on the contrary, it is composed of closely related different species belonging to the M. chelonae-M. abscessus complex and also several unidentified isolates. The detection of these isolates, putatively novel species, indicates a wider inner variability than the presently known in this complex. PMID:28533767
Lin, Philana Ling; Pawar, Santosh; Myers, Amy; Pegu, Amarenda; Fuhrman, Carl; Reinhart, Todd A.; Capuano, Saverio V.; Klein, Edwin; Flynn, JoAnne L.
Little is known regarding the early events of infection of humans with Mycobacterium tuberculosis. The cynomolgus macaque is a useful model of tuberculosis, with strong similarities to human tuberculosis. In this study, eight cynomolgus macaques were infected bronchoscopically with low-dose M. tuberculosis; clinical, immunologic, microbiologic, and pathologic events were assessed 3 to 6 weeks postinfection. Gross pathological abnormalities were observed as early as 3 weeks, including Ghon complex formation by 5 weeks postinfection. Caseous granulomas were observed in the lung as early as 4 weeks postinfection. Only caseous granulomas were observed in the lungs at these early time points, reflecting a rigorous initial response. T-cell activation (CD29 and CD69) and chemokine receptor (CXCR3 and CCR5) expression appeared localized to different anatomic sites. Activation markers were increased on cells from airways and only at modest levels on cells in peripheral blood. The priming of mycobacterium-specific T cells, characterized by the production of gamma interferon occurred slowly, with responses seen only after 4 weeks of infection. These responses were observed from T lymphocytes in blood, airways, and hilar lymph node, with responses predominantly localized to the site of infection. From these studies, we conclude that immune responses to M. tuberculosis are relatively slow in the local and peripheral compartments and that necrosis occurs surprisingly quickly during granuloma formation. PMID:16790751
Harding, Jeffrey S; Rayasam, Aditya; Schreiber, Heidi A; Fabry, Zsuzsanna; Sandor, Matyas
The disappearance and reformation of granulomas during tuberculosis has been described using PET/CT/X-ray in both human clinical settings and animal models, but the mechanisms of granuloma reformation during active disease remains unclear. Granulomas can recruit inflammatory dendritic cells (iDCs) that can regulate local T-cell responses and can carry bacteria into the lymph nodes, which is crucial for generating systemic T-cell responses against mycobacteria. Here, we report that a subset of mycobacterium-infected iDCs are associated with bacteria-specific T-cells in infected tissue, outside the granuloma, and that this results in the formation of new and/or larger multi-focal lesions. Mycobacterium-infected iDCs express less CCR7 and migrate less efficiently compared to the non-infected iDCs, which may support T-cell capture in granulomatous tissue. Capture may reduce antigen availability in the lymph node, thereby decreasing systemic priming, resulting in a possible regulatory loop between systemic T-cell responses and granuloma reformation. T-cell/infected iDCs clusters outside the granuloma can be detected during the acute and chronic phase of BCG and Mtb infection. Our studies suggest a direct role for inflammatory dendritic cells in the dissemination of granulomatous inflammation.
Mdluli, K; Swanson, J; Fischer, E; Lee, R E; Barry, C E
Isoniazid (INH), which acts by inhibiting mycolic acid biosynthesis, is very potent against the tuberculous mycobacteria. It is about 100-fold less effective against Mycobacterium avium. This difference has often been attributed to a decreased permeability of the cell wall. We measured the rate of conversion of radiolabelled INH to 4-pyridylmethanol by whole cells and cell-free extracts and estimated the permeability barrier imposed by the cell wall to INH influx in Mycobacterium tuberculosis and M. avium. There was no significant difference in the relative permeability to INH between these two species. However, the total conversion rate in M. tuberculosis was found to be four times greater. Examination of in vitro-generated mutants revealed that the major resistance mechanism for both species is loss of the catalase-peroxidase KatG. Analysis of lipid and protein biosynthetic profiles demonstrated that the molecular target of activated INH was identical for both species. M. avium, however, formed colonies at INH concentrations inhibitory for mycolic acid biosynthesis. These mycolate-deficient M. avium exhibited altered colony morphologies, modified cell wall ultrastructure and were 10-fold more sensitive to treatment with hydrophobic antibiotics, such as rifampin. These findings may significantly impact the design of new therapeutic regimens for the treatment of infections with atypical mycobacteria.
The tuberculosis situation in Portugal justifies the use of a strategy for the genotyping of Mycobacterium tuberculosis, particularly as Portugal is part of the global backdrop of human mobility, something which has a knock-on effect on the pandemic. Several international studies have placed spoligotyping and MIRU- VNTR typing as first line techniques for the molecular epidemiology of Mycobacterium tuberculosis as these techniques rely on simple technologies (PCR) and produce patterns which are easily translated into a direct interpretation numerical code. Spoligotyping has been accordingly proposed for all the isolates, while MIRU-VNTR typing should be applied to isolates with a common spoliotype. Other techniques, including IS6110-RFLP, should be reserved for use ill accordance with selected criteria. Previous studies in Portugal using spoligotyping have underlined the advantages of a strategy based on sampling consecutive patient isolates with no prior selection criteria. This allows characterisation of the M. tuberculosis population structure through monitoring the distribution of the genotypes geographically over time and within the various risk groups. On the other hand, the association of spoligotyping, MIRU-VNTF (typing and, possibly, other techniques, needs evaluating as part of bigger pictures, including identifying recent transmission situations, distinguishing between reinfection and relapse episodes and mapping the size and dynamics of disease transmission. The solution to the tuberculosis problem in Portugal implies structuring genotyping's role in tuberculosis prevention and control and its evaluation through concrete examples and results.
Philips, Rebecca C; Hunter-Ellul, Lindsey A; Martin, Julie E; Wilkerson, Michael G
We report an uncommon case of a cutaneous infection with Mycobacterium fortuitum arising in a new tattoo. A 29-year-old man presented with a several month history of a non-pruritic papular eruption within a tattoo; the papules developed 1-to-2 weeks after the tattoo procedure. He denied similar symptoms with previous tattoos. He had been treated unsuccessfully with cephalexin. Histopathologic examination revealed perifollicular chronic and granulomatous inflammation, consistent with chronic folliculitis. Acid-fast bacilli culture identified Mycobacterium fortuitum complex. The patient was treated with a 2-month course of oral trimethoprim-sulfamethoxazole (160mg/800mg twice daily) and ciprofloxacin (250 mg twice daily), with clinical improvement at follow up after three weeks of the antibiotic regimen. Rapidly growing mycobacteria have emerged as a cause of tattoo-associated cutaneous infection in recent years. Diagnosis and treatment can be difficult without clinical suspicion. M. fortuitum and other rapidly growing mycobacteria should be considered in the differential diagnosis of tattoo-associated dermatologic complications.
Wong, Cynthia; Ha, Ngan P.; Pawlowski, Michal E.; Graviss, Edward A.; Tkaczyk, Tomasz S.
While there have been research efforts to find faster and more efficient diagnostic techniques for tuberculosis (TB), it is equally important to monitor a patient’s response to treatment over time, especially with the increasing prevalence of multi-drug resistant (MDR) and extensively-drug resistant (XDR) TB. Between sputum smear microscopy, culture, and GeneXpert, only culture can verify viability of mycobacteria. However, it may take up to six weeks to grow Mycobacterium tuberculosis (Mtb), during which time the patient may have responded to treatment or the mycobacteria are still viable because the patient has MDR or XDR TB. In both situations, treatment incurs increased patient costs and makes them more susceptible to host-drug effects such as liver damage. Coenzyme Factor 420 (F420) is a fluorescent coenzyme found naturally in mycobacteria, with an excitation peak around 420 nm and an emission peak around 470 nm. Using Mycobacterium smegmatis, we show that live and dead mycobacteria undergo different rates of photobleaching over a period of 2 min. These preliminary experiments suggest that the different photobleaching rates could be used to help monitor a patient’s response to TB treatment. In future studies, we propose to describe these experiments with Mtb as both M. smegmatis and Mtb use F420. PMID:27742463
Yoon, Yina; Na, Yirang; Kim, Bum-Joon; Seok, Seung Hyeok
Human neutrophils have been known to release neutrophil extracellular traps (NETs), antimicrobial DNA structures capable of capturing and killing microbes. Recently, a similar phenomenon has been reported in macrophages infected with various pathogens. However, a role for macrophages extracellular traps (METs) in host defense responses against Mycobacterium massiliense (M. mass) has yet to be described. In this study, we show that M. mass, a rapid growing mycobacterium (RGM), also induces the release of METs from PMA-differentiated THP-1 cells. Intriguingly, this process is not dependent on NADPH oxidase activity, which regulates NET formation. Instead, M. mass-induced MET formation partially depends on calcium influx and requires phagocytosis of high bacterial load. The METs consist of a DNA backbone embedded with microbicidal proteins such as histone, MPO and elastase. Released METs entrap M. mass and prevent their dissemination, but do not have bactericidal activity. Instead, they result in enhanced bacterial growth. In this regard, METs were considered to provide interaction of M. mass with cells and an environment for bacterial aggregation, which may facilitate mycobacterial survival and growth. In conclusion, our results demonstrate METs as an innate defense response against M. mass infection, and suggest that extracellular traps play a multifaceted role in the interplay between host and bacteria. PMID:27191593
Godbole, Adwait Anand; Ahmed, Wareed; Bhat, Rajeshwari Subray; Bradley, Erin K.; Ekins, Sean
We describe inhibition of Mycobacterium tuberculosis topoisomerase I (MttopoI), an essential mycobacterial enzyme, by two related compounds, imipramine and norclomipramine, of which imipramine is clinically used as an antidepressant. These molecules showed growth inhibition of both Mycobacterium smegmatis and M. tuberculosis cells. The mechanism of action of these two molecules was investigated by analyzing the individual steps of the topoisomerase I (topoI) reaction cycle. The compounds stimulated cleavage, thereby perturbing the cleavage-religation equilibrium. Consequently, these molecules inhibited the growth of the cells overexpressing topoI at a low MIC. Docking of the molecules on the MttopoI model suggested that they bind near the metal binding site of the enzyme. The DNA relaxation activity of the metal binding mutants harboring mutations in the DxDxE motif was differentially affected by the molecules, suggesting that the metal coordinating residues contribute to the interaction of the enzyme with the drug. Taken together, the results highlight the potential of these small molecules, which poison the M. tuberculosis and M. smegmatis topoisomerase I, as leads for the development of improved molecules to combat mycobacterial infections. Moreover, targeting metal coordination in topoisomerases might be a general strategy to develop new lead molecules. PMID:25534741
Pavlinac, Patricia B.; Naulikha, Jaqueline M.; John-Stewart, Grace C.; Onchiri, Frankline M.; Okumu, Albert O.; Sitati, Ruth R.; Cranmer, Lisa M.; Lokken, Erica M.; Singa, Benson O.; Walson, Judd L.
In children, Mycobacterium tuberculosis (M. tuberculosis) frequently disseminates systemically, presenting with nonspecific signs including fever. We determined prevalence of M. tuberculosis bacteremia among febrile children presenting to hospitals in Nyanza, Kenya (a region with high human immunodeficiency virus (HIV) and M. tuberculosis prevalence). Between March 2013 and February 2014, we enrolled children aged 6 months to 5 years presenting with fever (axillary temperature ≥ 37.5°C) and no recent antibiotic use. Blood samples were collected for bacterial and mycobacterial culture using standard methods. Among 148 children enrolled, median age was 3.1 years (interquartile range: 1.8–4.1 years); 10.3% of children were living with a household member diagnosed with M. tuberculosis in the last year. Seventeen percent of children were stunted (height-for-age z-score < −2), 18.6% wasted (weight-for-height z-score < −2), 2.7% were HIV-infected, and 14.2% were HIV-exposed uninfected. Seventeen children (11.5%) had one or more signs of tuberculosis (TB). All children had a Bacille Calmette-Guerin vaccination scar. Among 134 viable blood cultures, none (95% confidence interval: 0–2.7%) had Mycobacterium isolated. Despite exposure to household TB contacts, HIV exposure, and malnutrition, M. tuberculosis bacteremia was not detected in this pediatric febrile cohort, a finding consistent with other pediatric studies. PMID:26324730
Harding, Jeffrey S.; Rayasam, Aditya; Schreiber, Heidi A.; Fabry, Zsuzsanna; Sandor, Matyas
The disappearance and reformation of granulomas during tuberculosis has been described using PET/CT/X-ray in both human clinical settings and animal models, but the mechanisms of granuloma reformation during active disease remains unclear. Granulomas can recruit inflammatory dendritic cells (iDCs) that can regulate local T-cell responses and can carry bacteria into the lymph nodes, which is crucial for generating systemic T-cell responses against mycobacteria. Here, we report that a subset of mycobacterium-infected iDCs are associated with bacteria-specific T-cells in infected tissue, outside the granuloma, and that this results in the formation of new and/or larger multi-focal lesions. Mycobacterium-infected iDCs express less CCR7 and migrate less efficiently compared to the non-infected iDCs, which may support T-cell capture in granulomatous tissue. Capture may reduce antigen availability in the lymph node, thereby decreasing systemic priming, resulting in a possible regulatory loop between systemic T-cell responses and granuloma reformation. T-cell/infected iDCs clusters outside the granuloma can be detected during the acute and chronic phase of BCG and Mtb infection. Our studies suggest a direct role for inflammatory dendritic cells in the dissemination of granulomatous inflammation. PMID:26515292
Choi, Ji-An; Kim, Myung-Hoon; Kim, Min-Su; Lee, Keun-Cheol
For recent years, use of autologous fat injection has increased significantly in facial contouring surgery. Along with such increase in use, complications like atypical mycoplasma infection have been also on the increasing trend. The authors report two cases of Mycobacterium chelonae infection that occurred after autologous fat injection. Patients were treated as infection that resistant to common antibiotics and results were negative to routine culture and Gram staining. Acid-fast bacillus stain, polymerase chain reaction (PCR) test and mycobacterial cultures were conducted for diagnosis under suspicion of atypical mycoplasma infection. Then, combination antibiotics therapy, surgical treatment, and steroid injection were performed for treatment. Both patients were diagnosed with Mycobacterium chelonae in PCR test. They were positive to mycobacterial cultures. Combination antibiotics therapy was repeated to improvement of symptom. However, they could not be free from side effects such as deformation in facial contour, scar and pigmentation even after full recovery. When chronic wound infections after autologous fat injection, we must suspect atypical or mycobacterial infection and conduct examinations for a early diagnosis and proper antibiotic therapy that is effective to the nontuberculous mycobacteria. PMID:25606492
The genome of Mycobacterium leprae, the causative agent of leprosy, was analyzed by rapid sequencing of cosmids and plasmids prepared from DNA isolated from one patient's strain. Results showed that the bacillus possesses a single circular chromosome that differs from other known mycobacterium chromosomes with regard to size (3.2 Mb) and G + C content (57.8%). Computer analysis demonstrated that only half of the sequence contains protein-coding genes. The other half contains pseudogenes and non-coding sequences. These findings indicate that M. leprae has undergone a major reductive evolution leaving a minimal set of functional genes for survival. Study of the coding region of the sequence provides evidence accounting for the particular pathogenic properties of M. leprae which is an obligate intracellular parasite. Disappearance of numerous enzymatic pathways in comparison with M. tuberculosis, an intracellular pathogen comparable to M. leprae, could explain the differences observed between the two organisms. Genomic analysis of the leprosy bacillus also provided insight into the molecular basis for resistance to various antibiotics and allowed identification of several potential targets for new drug treatments.
Bernut, Audrey; Herrmann, Jean-Louis; Kissa, Karima; Dubremetz, Jean-François; Gaillard, Jean-Louis; Lutfalla, Georges; Kremer, Laurent
Mycobacterium abscessus is a rapidly growing Mycobacterium causing a wide spectrum of clinical syndromes. It now is recognized as a pulmonary pathogen to which cystic fibrosis patients have a particular susceptibility. The M. abscessus rough (R) variant, devoid of cell-surface glycopeptidolipids (GPLs), causes more severe clinical disease than the smooth (S) variant, but the underlying mechanisms of R-variant virulence remain obscure. Exploiting the optical transparency of zebrafish embryos, we observed that the increased virulence of the M. abscessus R variant compared with the S variant correlated with the loss of GPL production. The virulence of the R variant involved the massive production of serpentine cords, absent during S-variant infection, and the cords initiated abscess formation leading to rapid larval death. Cording occurred within the vasculature and was highly pronounced in the central nervous system (CNS). It appears that M. abscessus is transported to the CNS within macrophages. The release of M. abscessus from apoptotic macrophages initiated the formation of cords that grew too large to be phagocytized by macrophages or neutrophils. This study is a description of the crucial role of cording in the in vivo physiopathology of M. abscessus infection and emphasizes cording as a mechanism of immune evasion. PMID:24567393
Lu, Bin; Xu, Shunqing; Chen, Zifei; Zhou, Yikai
With the persisting increase of drug-resistant stains of M. Tuberculosis around the world, rapid and sensitive detection of antibiotic of M. Tuberculosis is becoming more and more important. In the present study, drug susceptibility of M. tuberculosis were detected by recombination mycobacteriophage combined with bioluminescence sensor. It is based on the use of recombination mycobacteriophage which can express firefly luciferase when it infects viable mycobacteria, and can effectively produce quantifiable photon. Meanwhile, in mycobacterium cells treated with active antibiotic, no light is observed. The emitted light is recorded by a bioluminscence sensor, so the result of drug-resistant test can be determined by the naked eye. 159 stains of M. tuberculosis were applied to this test on their resistant to rifampin, streptomycin and isoniazid. It is found that the agreement of this assay with Liewenstein- Jensen slat is: rifampin 95.60 percent, isoniazid 91.82 percent, streptomycin 88.68 percent, which showed that it is a fast and practical method to scene and detect drug resistant of mycobacterium stains.
Kaur, Parvinder; Ghosh, Anirban; Krishnamurthy, Ramya Vadageri; Bhattacharjee, Deepa Gagwani; Achar, Vijayashree; Datta, Santanu; Narayanan, Shridhar; Anbarasu, Anand; Ramaiah, Sudha
Exposure to Mycobacterium tuberculosis (Mtb) aerosols is a major threat to tuberculosis (TB) researchers, even in bio-safety level-3 (BSL-3) facilities. Automation and high-throughput screens (HTS) in BSL3 facilities are essential for minimizing manual aerosol-generating interventions and facilitating TB research. In the present study, we report the development and validation of a high-throughput, 24-well ‘spot-assay’ for selecting bactericidal compounds against Mtb. The bactericidal screen concept was first validated in the fast-growing surrogate Mycobacterium smegmatis (Msm) and subsequently confirmed in Mtb using the following reference anti-tubercular drugs: rifampicin, isoniazid, ofloxacin and ethambutol (RIOE, acting on different targets). The potential use of the spot-assay to select bactericidal compounds from a large library was confirmed by screening on Mtb, with parallel plating by the conventional gold standard method (correlation, r2 = 0.808). An automated spot-assay further enabled an MBC90 determination on resistant and sensitive Mtb clinical isolates. The implementation of the spot-assay in kinetic screens to enumerate residual Mtb after either genetic silencing (anti-sense RNA, AS-RNA) or chemical inhibition corroborated its ability to detect cidality. This relatively simple, economical and quantitative HTS considerably minimized the bio-hazard risk and enabled the selection of novel vulnerable Mtb targets and mycobactericidal compounds. Thus, spot-assays have great potential to impact the TB drug discovery process. PMID:25693161
Inoue, Shinnosuke; Lee, Hyun-Boo; Becker, Annie L; Weigel, Kris M; Kim, Jong-Hoon; Lee, Kyong-Hoon; Cangelosi, Gerard A; Chung, Jae-Hyun
Multi-drug resistant tuberculosis (MDR-TB) has become a serious concern for proper treatment of patients. As a phenotypic method, dielectrophoresis can be useful but is yet to be attempted to evaluate Mycobacterium tuberculosis complex cells. This paper investigates the dielectrophoretic behavior of Mycobacterium bovis (Bacillus Calmette-Guérin, BCG) cells that are treated with heat or antibiotics rifampin (RIF) or isoniazid (INH). The experimental parameters are designed on the basis of our sensitivity analysis. The medium conductivity (σ(m)) and the frequency (f) for a crossover frequency (f(xo1)) test are decided to detect the change of σ(m)-f(xo1) in conjunction with the drug mechanism. Statistical modeling is conducted to estimate the distributions of viable and nonviable cells from the discrete measurement of f (xo1). Finally, the parameters of the electrophysiology of BCG cells, C(envelope) and σ(cyto), are extracted through a sampling algorithm. This is the first evaluation of the dielectrophoresis (DEP) approach as a means to assess the effects of antimicrobial drugs on M. tuberculosis complex cells.