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Joseph O Falkinham - One of the best experts on this subject based on the ideXlab platform.
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SESSION V Recent Experience in the Epidemiology of Disease Caused by Atypical Mycobacteria
2016Co-Authors: Howard Gruft, Joseph O Falkinham, Bruce C ParkerAbstract:To obtain information on the epidemiology of mycobacteriosis, water and air samples collected along the East Coast of the United States were examined for mycobacteria. Mycobacterium avium-intracellulare-scrofulaceum (MAIS) were isolated from 25070 of the water, samples, mostly those from South Carolina, Georgia, and the Gulf states. Mycobacterium kansasii and Mycobacterium marinum were not found, probably because of the detrimental effects of the NaOH used to decontaminate the samples. MAIS strains were found more often in estuaries than in fresh or ocean waters. The fre-quency of Mycobacterium intracel/ulare was relatively uniform along the entire coast, while Mycobacterium scrofulaceum predominated in the South. Only M. intracellulare was found in aerosol specimens, although both M. intracellulare and M. scrofulaceum were found in waters collected at the same sites. Although infection by nontuberculous (atypical) mycobacteria has been recognized for 25 years [1], its epidemiology is still obscure [2]. These bacteria have been found in the environment [2, 3], and th
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microaerobic growth and anaerobic survival of Mycobacterium avium Mycobacterium intracellulare and Mycobacterium scrofulaceum
The International Journal of Mycobacteriology, 2015Co-Authors: Amy Herndon Lewis, Joseph O FalkinhamAbstract:Representative strains of Mycobacterium avium, Mycobacterium intracellulare and Mycobacterium scrofulaceum (MAIS) grew at equal rates in laboratory medium at 21% (air) and 12% oxygen. Growth in 6% oxygen proceeded at a 1.4–1.8-fold lower rate. Colony formation was the same at 21% (air) and 6% oxygen. The MAIS strains survived rapid shifts from aerobic to anaerobic conditions as measured by two experimental approaches (Falkinham (1996) [1]). MAIS cells grown aerobically to log phase in broth were diluted, spread on agar medium, and incubated anaerobically for up to 20 days at 37 °C. Although no colonies formed anaerobically, upon transfer to aerobic conditions, greater than 25% of the colony forming units (CFU) survived after 20 days of anaerobic incubation (Prince et al. (1989) [2]). MAIS cells grown in broth aerobically to log phase were sealed and vigorous agitation led to oxygen depletion (Wayne model). After 12 days anaerobic incubation, M. avium and M. scrofulaceum survival were high (>50%), while M. intracellulare survival was lower (22%). M. avium cells shifted to anaerobiosis in broth had increased levels of glycine dehydrogenase and isocitrate lyase. Growth of MAIS strains at low oxygen levels and their survival following a rapid shift to anaerobiosis is consistent with their presence in environments with fluctuating oxygen levels.
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factors influencing the chlorine susceptibility of Mycobacterium avium Mycobacterium intracellulare and Mycobacterium scrofulaceum
Applied and Environmental Microbiology, 2003Co-Authors: Joseph O FalkinhamAbstract:The susceptibility of representative strains of Mycobacterium avium, Mycobacterium intracellulare, and Mycobacterium scrofulaceum (the MAIS group) to chlorine was studied to identify factors related to culture conditions and growth phase that influenced susceptibility. M. avium and M. intracellulare strains were more resistant to chlorine than were strains of M. scrofulaceum. Transparent and unpigmented colony variants were more resistant to chlorine than were their isogenic opaque and pigmented variants (respectively). Depending on growth stage and growth rate, MAIS strains differed in their chlorine susceptibilities. Cells from strains of all three species growing in early log phase at the highest growth rates were more susceptible than cells in log and stationary phase. Rapidly growing cells were more susceptible to chlorine than slowly growing cells. The chlorine susceptibility of M. avium cells grown at 30°C was increased when cells were exposed to chlorine at 40°C compared to susceptibility after exposure at 30°C. Cells of M. avium grown in 6% oxygen were significantly more chlorine susceptible than cells grown in air. Chlorine-resistant MAIS strains were more hydrophobic and resistant to Tween 80, para-nitrobenzoate, hydroxylamine, and nitrite than were the chlorine-sensitive strains.
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fluorescent acid fast microscopy for measuring phagocytosis of Mycobacterium avium Mycobacterium intracellulare and Mycobacterium scrofulaceum by tetrahymena pyriformis and their intracellular growth
Applied and Environmental Microbiology, 2001Co-Authors: Eileen D Strahl, Glenda E Gillaspy, Joseph O FalkinhamAbstract: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°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.
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epidemiology of infection by nontuberculous mycobacteria Mycobacterium avium Mycobacterium intracellulare and Mycobacterium scrofulaceum in acid brown water swamps of the southeastern united states and their association with environmental variables
The American review of respiratory disease, 1992Co-Authors: Richard A Kirschner, Bruce C Parker, Joseph O FalkinhamAbstract:Mycobacterium avium, Mycobacterium intracellulare, and Mycobacterium scrofulaceum (MAIS) organisms were isolated and identified from waters, soils, aerosols, and droplets ejected from water collected from four geographically separate aquatic environments (Okefenokee Swamp, GA; Dismal Swamp, VA; Claytor Lake, VA; and Cranberry Glades, WV) during several seasons. Recovery of MAIS was significantly higher from waters, soils, and aerosols collected from the two acid, brown-water swamps located in the southeastern coastal plain. High MAIS numbers correlated with warmer temperature, low pH, low dissolved oxygen, high soluble zinc, high humic acid, and high fulvic acid. This research, in relation to previous findings for the geographic distribution and physiologic ecology of MAIS, supports the conclusion that waters, soils, and aerosols of the acid, brown-water swamps of the southeastern United States coastal plain represent major environmental sources likely connected with the higher incidence of human infectio...
Amin Kabani - One of the best experts on this subject based on the ideXlab platform.
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Mycobacterium parascrofulaceum sp nov novel slowly growing scotochromogenic clinical isolates related to Mycobacterium simiae
International Journal of Systematic and Evolutionary Microbiology, 2004Co-Authors: Christine Y Turenne, Victoria J Cook, Tamara Burdz, Ryan J Pauls, L Thibert, Joyce Wolfe, Amin KabaniAbstract:A group of pigmented, slowly growing mycobacteria identified by 16S rRNA gene sequencing as ‘MCRO 33’ (GenBank accession no. AF152559) have been isolated from several clinical specimens in various laboratories across Canada. Genotypically, the organism is most closely related to Mycobacterium simiae. However, it presents with a similar phenotypic profile to Mycobacterium scrofulaceum. Several reference strains obtained from ATCC and TMC culture collections, previously identified as M. scrofulaceum or M. simiae, have also been found to possess the MCRO 33 16S rRNA gene sequence. Biochemical testing, susceptibility testing, HPLC, hsp65 gene and 16S–23S spacer (ITS1) sequencing were performed on clinical and reference strains to characterize further this unique species. Of the clinical strains, one was isolated from a cervix biopsy whereas all other clinical isolates were obtained from respiratory samples. In one patient, symptoms, imaging and repeat clinical specimens positive on culture for this organism were suggestive of active clinical disease. The description of this species, for which the name Mycobacterium parascrofulaceum sp. nov. is proposed, follows the present trend of a large number of novel Mycobacterium species identified due in great part to sequence-based methods. The type strain is HSC68T (=ATCC BAA-614T=DSM 44648T).
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a high proportion of novel mycobacteria species identified by 16s rdna analysis among slowly growing accuprobe negative strains in a clinical setting
American Journal of Clinical Pathology, 2003Co-Authors: Ryan J Pauls, Christine Y Turenne, Joyce Wolfe, Amin KabaniAbstract:Sequencing of the 16S ribosomal DNA (rDNA )for identification of nontuberculous mycobacteria (NTM) has contributed to the establishment of more than 35 new species during the last decade. Increasingly, NTM are accepted as potential or proven pathogens. We identified, by 16S rDNA sequence analysis, slowly growing NTM isolates negative by AccuProbe (GenProbe, San Diego, CA) that previously were identified by using conventional biochemical techniques, to determine the accuracy of reporting AccuProbenegative NTM prior to sequence-based identification. Of 82 strains, 30 were deemed novel. An attempt was made to determine the clinical importance of previously misidentified novel species. Clinical cases are described for a number of strains previously identified as Mycobacterium terrae complex, Mycobacterium scrofulaceum, and Mycobacterium avium complex. As sequence-based identification methods become more commonplace in clinical microbiology laboratories, there is a need to understand the significance of previously undescribed species, which often mimic and subsequently are identified as well-established species. Many nontuberculous mycobacteria (NTM) are ubiquitous in the environment and may colonize and occasionally cause infection in humans. Mycobacterium avium complex, Mycobacterium kansasii, and members of the Mycobacterium fortuitum complex are causative agents for most NTM infections and currently have a well-understood environmental epidemiology. 1 Other NTM species rarely cause infection,
Patrick J. Brennan - One of the best experts on this subject based on the ideXlab platform.
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SESSION III Structures of the Typing Antigens of Atypical Mycobacteria: A Brief Review of Present Knowledge
2016Co-Authors: Patrick J. Brennan, From Department, Clinical LaboratoriesAbstract:The overall structures of the typing antigens from serovars in the Mycobacterium avium-Mycobacterium intracellulare-Mycobacterium scrofulaceum complex have been elucidated. They are polar versions of the well-known C mycosides and have the general structure
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structures of the glycopeptidolipid antigens from serovars in the Mycobacterium avium Mycobacterium intracellulare Mycobacterium scrofulaceum serocomplex
FEBS Journal, 2005Co-Authors: Patrick J. Brennan, G O Aspinall, Hubert Mayer, Jeong Nam E ShinAbstract:The ‘C-mycosidic’ glycopeptidolipid typing antigens from all serovars in the Mycobacterium avium/M. intracellulare/M. scrofulaceum complex have been examined to varying extents. Detailed analysis of those from serovars 8, 9, 16 and 25 show that the antigens consist of short acetylated oligosaccharides linked to a common fattyacyl-peptidyl-O-(3.4-di-O-methylrhamnose) ‘core’. The oligosaccharide units, in a form suitable for chemical studies, were liberated as oligosaccharide alditols on treatment of the glycopeptidolipids with alkaline borohydride solution. The alditol in the reduced oligosaccharides from all sources is 6-deoxytalitol. Moreover rhamnose is also always present, indicating that a ‘basal’ disaccharide, rhamnosyl-6-deoxytalosyl, is always linked to the allo-threonine in the acylpeptide. In addition the oligosaccharides from the glycopeptidolipids of each serovar are distinguished by their own individualistic sugars: 3-O-methylglucose in serovar 8; 2,3-di-O-methylfucose in serovar 9; 2-O-methylfucose in serovar 25; 4-O-methylrhamnose in the oligosaccharide from one of the two glycopeptidolipids in serovar 16 and apparently another rhamnosyl substituent in the other oligosaccharide. The glycopeptidolipid antigens in their structural principals, cellular location and physiological role bear a striking mmiscular resemblance to cell wall components of other bacteria such as the O-antigenic and R-antigenic lipopolysaccharides.
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Purification, characterization, gene sequence, and significance of a bacterioferritin from Mycobacterium leprae.
Journal of Experimental Medicine, 1994Co-Authors: M. C. V. Pessolani, D. R. Smith, Becky Rivoire, J. Mccormick, S. A. Hefta, Stewart T. Cole, Patrick J. BrennanAbstract:The study of tissue-derived Mycobacterium leprae provides insights to the immunopathology of leprosy and helps identify broad molecular features necessary for mycobacterial parasitism. A major membrane protein (MMP-II) of in vivo-derived M. leprae previously recognized (Hunter, S.W., B. Rivoire, V. Mehra, B.R. Bloom, and P.J. Brennan. 1990. J. Biol. Chem. 265:14065) was purified from extracts of the organism and partial amino acid sequence obtained. This information allowed recognition, within one of the cosmids that encompass the entire M. leprae genome, of a complete gene, bfr, encoding a protein of subunit size 18.2 kD. The amino acid sequence deduced from the major membrane protein II (MMP-II) gene revealed considerable homology to several bacterioferritins. Analysis of the native protein demonstrated the iron content, absorption spectrum, and large native molecular mass (380 kD) of several known bacterioferritins. The ferroxidase-center residues typical of ferritins were conserved in the M. leprae product. Oligonucleotides derived from the amino acid sequence of M. leprae bacterioferritin enabled amplification of much of the MMP-II gene and the detection of homologous sequences in Mycobacterium paratuberculosis, Mycobacterium avium, Mycobacterium tuberculosis, Mycobacterium intracellulare, and Mycobacterium scrofulaceum. The role of this iron-rich protein in the virulence of M. leprae is discussed.
James M Musser - One of the best experts on this subject based on the ideXlab platform.
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identification and subspecific differentiation of Mycobacterium scrofulaceum by automated sequencing of a region of the gene hsp65 encoding a 65 kilodalton heat shock protein
Journal of Clinical Microbiology, 1996Co-Authors: Douglas S Swanson, Xi Pan, James M MusserAbstract:Mycobacterium scrofulaceum is most commonly recovered from children with cervical lymphadenitis, although it also accounts for approximately 2% of the mycobacterial infections in AIDS patients. Species assignment of M. scrofulaceum isolated by conventional techniques can be difficult and time-consuming. To develop a strategy for rapid species assignment of these organisms, a 360-bp region of the gene (hsp65) encoding a 65-kDa heat shock protein in 37 isolates from diverse sources was sequenced. Eight hsp65 alleles were identified, and these sequences formed phylogenetic clusters and lineages largely distinct from other Mycobacterium species. There was incomplete correlation between serovar designation and hsp65 allele assignment. The hsp65 data correlated strongly with the results of sequence analysis of the gene coding for 16S rRNA. Automated DNA sequencing of a 360-bp region of the hsp65 gene provides a rapid and unambiguous method for species assignment of these acid-fast organisms for diagnostic purposes.
Jeanlouis Herrmann - One of the best experts on this subject based on the ideXlab platform.
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use of the inno lipa mycobacteria assay version 2 for identification of Mycobacterium avium Mycobacterium intracellulare Mycobacterium scrofulaceum complex isolates
Journal of Clinical Microbiology, 2005Co-Authors: L Lebrun, Francoisxavier Weill, Leila Lafendi, Florence Houriez, Francois Casanova, Cristina M Gutierrez, Didier Ingrand, P H Lagrange, Veronique Vincent, Jeanlouis HerrmannAbstract:Using INNO-LiPA-MYCOBACTERIA (Lipav1; Innogenetics) and the AccuProbe (Gen-Probe Inc./bioMerieux) 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.
