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1.
Chem Phys Lipids ; 230: 104928, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32492381

RESUMO

Mycolic acid methyl esters were extracted from Mycobacterium avium by a mild saponification protocol, designed to preserve labile components. The resulting mixture of α-, keto- and wax ester mycolates was accompanied by some degraded ω-carboxymycolic acid dimethyl esters, whose overall structures were found to support previous studies. Chromatography of the mono-carboxylic mycolates gave an inseparable mixture of keto- and wax ester mycolates and separate α-mycolates. Reduction of the ketomycolate components allowed isolation and characterisation of intact wax ester mycolates for the first time. Minor α- and ω-carboxymycolates were detected in which methyl branches were located on either the proximal or distal sides of trans-alkene groups.


Assuntos
Mycobacterium avium/química , Ácidos Micólicos/química , Alcenos/química , Dimerização , Ésteres/química , Ácidos Micólicos/isolamento & purificação , Estereoisomerismo
2.
J Mol Model ; 25(3): 68, 2019 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-30762132

RESUMO

Mycobacterium tuberculosis remains a persistent pathogen, partly due to its lipid rich cell wall, of which mycolic acids (MAs) are a major component. The fluidity and conformational flexibilities of different MAs in the bacterial cell wall significantly influence its properties, function, and observed pathogenicity; thus, a proper conformational description of different MAs in different environments (e.g., in vacuum, in solution, in monolayers) can inform about their potential role in the complex setup of the bacterial cell wall. Previously, we have shown that molecular dynamics (MD) simulations of MA folding in vacuo can be used to characterize MA conformers in seven groupings relating to bending at the functional groups (W, U and Z-conformations). Providing a new OPLS-based forcefield parameterization for the critical cyclopropyl group of MAs and extensive simulations in explicit solvents (TIP4P water, hexane), we now present a more complete picture of MA folding properties together with improved simulation analysis techniques. We show that the 'WUZ' distance-based analysis can be used to pinpoint conformers with hairpin bends at the functional groups, with these conformers constituting only a fraction of accessible conformations. Applying principle component analysis (PCA) and refinement using free energy landscapes (FELs), we are able to discriminate a complete and unique set of conformational preferences for representative alpha-, methoxy- and keto-MAs, with overall preference for folded conformations. A control backbone-MA without any mero-chain functional groups showed significantly less folding in the mero-chain, confirming the role of functionalization in directing folding. Keto-MA showed the highest percentage of WUZ-type conformations and, in particular, a tendency to fold at its alpha-methyl trans-cyclopropane group, in agreement with results from Villeneuve et al. MAs demonstrate similar folding in vacuum and water, with a majority of folded conformations around the W-conformation, although the molecules are more flexible in vacuum than in water. Exchange between conformations, with a disperse distribution that includes unfolded conformers, is common in hexane for all MAs, although with more organization for Keto-MA. Globular, folded conformations are newly defined and may be specifically relevant in biofilms. Graphical abstract Through advanced simulation analysis, including principle component analysis and free energy landscapes, we reveal detailed physical insights into the solvent-dependant folding behavior of mycolic acids from M. tb.


Assuntos
Mycobacterium tuberculosis/química , Ácidos Micólicos/química , Conformação Molecular , Simulação de Dinâmica Molecular , Ácidos Micólicos/isolamento & purificação , Análise de Componente Principal , Solventes
3.
PLoS One ; 14(1): e0209196, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30608942

RESUMO

Intravesical therapy using Mycobacterium bovis bacillus Calmette-Guérin (BCG) is the most established cancer immunotherapy for bladder cancer. However, its underlying mechanisms are unknown. Mycolic acid (MA), the most abundant lipid of the BCG cell wall, is suspected to be one of the essential active components of this immunogenicity. Here, we developed cationic liposomes incorporating three subclasses (α, keto, and methoxy) of MA purified separately from BCG, using the dendron-bearing lipid D22. The cationic liposomes using D22 were efficiently taken up by the murine bladder cancer cell line MB49 in vitro, but the non-cationic liposomes were not. Lip-kMA, a cationic liposome containing keto-MA, presented strong antitumor activity in two murine syngeneic graft models using the murine bladder cancer cell lines MB49 and MBT-2 in comparison to both Lip-aMA and Lip-mMA, which contained α-MA and methoxy-MA, respectively. Interestingly, Lip-kMA(D12), which was made of D12 instead of D22, did not exhibit antitumor activity in the murine syngeneic graft model using MB49 cells, although it was successfully taken up by MB49 cells in vitro. Histologically, compared to the number of infiltrating CD4 lymphocytes, the number of CD8 lymphocytes was higher in the tumors treated with Lip-kMA. Antitumor effects of Lip-kMA were not observed in nude mice, whereas weak but significant effects were observed in beige mice with natural killer activity deficiency. Thus, a cationized liposome containing keto-MA derived from BCG induced in vivo antitumor immunity. These findings will provide new insights into lipid immunogenicity and the underlying mechanisms of BCG immunotherapy.


Assuntos
Vacina BCG/uso terapêutico , Vacinas Anticâncer/uso terapêutico , Ácidos Micólicos/uso terapêutico , Neoplasias da Bexiga Urinária/tratamento farmacológico , Neoplasias da Bexiga Urinária/imunologia , Animais , Vacina BCG/administração & dosagem , Vacina BCG/química , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Vacinas Anticâncer/administração & dosagem , Vacinas Anticâncer/química , Linhagem Celular Tumoral , Feminino , Humanos , Imunoterapia , Cetoácidos/administração & dosagem , Cetoácidos/isolamento & purificação , Cetoácidos/uso terapêutico , Lipossomos/administração & dosagem , Lipossomos/química , Lipossomos/ultraestrutura , Linfócitos do Interstício Tumoral/imunologia , Camundongos , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Camundongos Nus , Estrutura Molecular , Ácidos Micólicos/administração & dosagem , Ácidos Micólicos/isolamento & purificação , Tamanho da Partícula , Neoplasias da Bexiga Urinária/patologia
4.
Microb Pathog ; 117: 243-246, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29481974

RESUMO

Haptoglobin (Hp) and Serum Amyloid A (SAA) are a group of blood proteins whose concentrations in animals can be influenced by infection, inflammation, surgical trauma or stress. Corynebacterium pseudotuberculosis is the causative agent of caseous lymphadenitis (CLA), and Mycolic acid is a virulent factor extracted from C. pseudotuberculosis. There is a dearth of sufficient evidence on the clinical implication of MAs on the responses of Hp and SAA in goats. Therefore, this study was conducted to evaluate the potential effects of Mycolic acid (MAs) and C. pseudotuberculosis on the responses of Hp and SAA in female goats. A total of 12 healthy female goats was divided into three groups; A, B and C each comprising of 4 goats and managed for a period of three months. Group (A) was inoculated with 2 mL of sterile phosphate buffered saline (as a negative control group) intradermally, while group (B) and (C) were inoculated intradermally with 2 ml each of mycolic acid and 1  × 109 cfu of active C. pseudotuberculosis respectively. The result of the study showed that the Hp concentration in goats inoculated with C. pseudotuberculosis was significantly increased up to 7-fold (1.17 ±â€¯0.17 ng/L) while MAs showed a 3-fold increased (0.83 ±â€¯0.01 ng/L) compared with the control. Whereas SAA concentration in C. pseudotuberculosis and MAs groups showed a significant 3-fold (17.85 ±â€¯0.91 pg/mL) and 2-fold (10.97 ±â€¯0.71 pg/mL) increased compared with the control. This study concludes that inoculation of C. pseudotuberculosis and MAs have significant effects on Hp and SAA levels, which indicates that MAs could have a role in the pathogenesis of caseous lymphadenitis.


Assuntos
Infecções por Corynebacterium/sangue , Infecções por Corynebacterium/imunologia , Corynebacterium pseudotuberculosis/metabolismo , Haptoglobinas/metabolismo , Ácidos Micólicos/farmacologia , Proteína Amiloide A Sérica/metabolismo , Animais , Infecções por Corynebacterium/microbiologia , Infecções por Corynebacterium/veterinária , Corynebacterium pseudotuberculosis/isolamento & purificação , Feminino , Doenças das Cabras/sangue , Cabras/sangue , Haptoglobinas/análise , Linfadenite/microbiologia , Ácidos Micólicos/isolamento & purificação , Proteína Amiloide A Sérica/análise
5.
Microbiology (Reading) ; 159(Pt 11): 2405-2415, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24014663

RESUMO

The oxygenated long-chain mycolic acids from many mycobacteria are characterized by the presence of mid-chain cyclopropane groups, which can have either cis-configuration or trans-configuration with an adjacent methyl branch. To determine the effect of these functional groups on mycolic acid conformation, surface pressure (π) versus mean molecular area isotherms of methoxy- (MeO-) mycolic acids (MAs) from Mycobacterium kansasii, Mycobacterium tuberculosis (Mtb) Canetti and Mtb H37Ra, and of keto-MAs from Mycobacterium avium-intracellulare complex (MAC) and Mtb H37Ra were recorded and analysed. The MeO- and keto-MAs from Mtb H37Ra, containing scarcely any trans-cyclopropyl groups, apparently took no fully folded 'W-form' conformations. Keto-MA from MAC, whose trans-cyclopropyl group content is nearly 90 %, showed a very solid W-form conformation. MeO-MAs from M. kansasii and Mtb Canetti gave stable W-form conformations at lower temperatures and surface pressures and extended conformations at higher temperatures and surface pressures; their W-form conformation was not as stable as expected from their cis-cyclopropyl group content, probably because they had a wide range of constituent homologues. Energy level calculations of cis- or α-methyl trans-cyclopropane-containing model molecules and computer simulation studies confirmed the superior folding properties of the latter functional unit. The present results were compared with those of MeO- and keto-MAs from Mtb and from M. bovis Bacillus Calmette-Guérin (BCG) reported previously. Among the oxygenated MAs, those having higher trans-cyclopropane content tended to take W-form conformations more firmly, implying that the meromycolate proximal intra-chain α-methyl trans-cyclopropane groups facilitated MA folding more than cis-cyclopropane groups.


Assuntos
Complexo Mycobacterium avium/química , Mycobacterium kansasii/química , Mycobacterium tuberculosis/química , Ácidos Micólicos/química , Simulação por Computador , Conformação Molecular , Ácidos Micólicos/isolamento & purificação
6.
J Lipid Res ; 54(10): 2924-32, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23797850

RESUMO

Tuberculosis is a major cause of mortality and morbidity due to infectious disease. However, current clinical diagnostic methodologies such as PCR, sputum culture, or smear microscopy are not ideal. Antibody-based assays are a suitable alternative but require specific antibodies against a suitable biomarker. Mycolic acid, which has been found in patient sputum samples and comprises a large portion of the mycobacterial cell wall, is an ideal target. However, generating anti-lipid antibodies using traditional hybridoma methodologies is challenging and has limited the exploitation of this lipid as a diagnostic marker. We describe here the isolation and characterization of four anti-mycolic acid antibodies from a nonimmune antibody phage display library that can detect mycolic acids down to a limit of 4.5ng. All antibodies were specific for the methoxy subclass of mycolic acid with weak binding for α mycolic acid and did not show any binding to closely related lipids or other Mycobacterium tuberculosis (Mtb) derived lipids. We also determined the clinical utility of these antibodies based on their limit of detection for mycobacteria colony forming units (CFU). In combination with an optimized alkaline hydrolysis method for rapid lipid extraction, these antibodies can detect 10(5) CFU of Mycobacterium bovis BCG, a close relative of Mtb and therefore represent a novel approach for the development of diagnostic assays for lipid biomarkers.


Assuntos
Anticorpos Antibacterianos/química , Ácidos Micólicos/imunologia , Tuberculose Pulmonar/diagnóstico , Anticorpos Antibacterianos/biossíntese , Especificidade de Anticorpos , Biomarcadores/metabolismo , Técnicas de Visualização da Superfície Celular , Ensaio de Imunoadsorção Enzimática , Células HEK293 , Humanos , Limite de Detecção , Mycobacterium bovis/metabolismo , Mycobacterium smegmatis/metabolismo , Ácidos Micólicos/isolamento & purificação , Ácidos Micólicos/metabolismo , Ligação Proteica , Tuberculose Pulmonar/metabolismo
7.
PLoS One ; 7(7): e41923, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22860031

RESUMO

Tracing the evolution of ancient diseases depends on the availability and accessibility of suitable biomarkers in archaeological specimens. DNA is potentially information-rich but it depends on a favourable environment for preservation. In the case of the major mycobacterial pathogens, Mycobacterium tuberculosis and Mycobacterium leprae, robust lipid biomarkers are established as alternatives or complements to DNA analyses. A DNA report, a decade ago, suggested that a 17,000-year-old skeleton of extinct Bison antiquus, from Natural Trap Cave, Wyoming, was the oldest known case of tuberculosis. In the current study, key mycobacterial lipid virulence factor biomarkers were detected in the same two samples from this bison. Fluorescence high-performance liquid chromatography (HPLC) indicated the presence of mycolic acids of the mycobacterial type, but they were degraded and could not be precisely correlated with tuberculosis. However, pristine profiles of C(29), C(30) and C(32) mycocerosates and C(27) mycolipenates, typical of the Mycobacterium tuberculosis complex, were recorded by negative ion chemical ionization gas chromatography mass spectrometry of pentafluorobenzyl ester derivatives. These findings were supported by the detection of C(34) and C(36) phthiocerols, which are usually esterified to the mycocerosates. The existence of Pleistocene tuberculosis in the Americas is confirmed and there are many even older animal bones with well-characterised tuberculous lesions similar to those on the analysed sample. In the absence of any evidence of tuberculosis in human skeletons older than 9,000 years BP, the hypothesis that this disease evolved as a zoonosis, before transfer to humans, is given detailed consideration and discussion.


Assuntos
Mycobacterium tuberculosis/química , Ácidos Micólicos/análise , Tuberculose/veterinária , Fatores de Virulência/análise , Animais , Biomarcadores/análise , Bison , Osso e Ossos/química , Osso e Ossos/microbiologia , Cromatografia Líquida de Alta Pressão , Extinção Biológica , Humanos , Lipídeos/análise , Lipídeos/isolamento & purificação , Ácidos Micólicos/isolamento & purificação , Tuberculose/microbiologia , Fatores de Virulência/isolamento & purificação
8.
J Microbiol ; 50(2): 235-40, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22538651

RESUMO

Corynebacterium glutamicum is widely used for producing amino acids. Mycolic acids, the major components in the cell wall of C. glutamicum might be closely related to the secretion of amino acids. In this study, mycolic acids were extracted from 5 strains of C. glutamicum, including ATCC 13032, ATCC 13869, ATCC 14067, L-isoleucine producing strain IWJ-1, and L-valine producing strain VWJ-1. Structures of these mycolic acids were analyzed using thin layer chromatography and electrospray ionization mass spectrometry. More than twenty molecular species of mycolic acid were observed in all 5 strains. They differ in the length (20-40 carbons) and saturation (0-3 double bonds) of their constituent fatty acids. The dominant species of mycolic acid in every strain was different, but their two hydrocarbon chains were similar in length (14-18 carbons), and the meromycolate chain usually contained double bonds. As the growth temperature of cells increased from 30°C to 34°C, the proportion of mycolic acid species containing unsaturated and shorter hydrocarbon chains increased. These results provide new information on mycolic acids in C. glutamicum, and could be useful for modifying the cell wall to increase the production of amino acids.


Assuntos
Corynebacterium glutamicum/metabolismo , Ácidos Micólicos/química , Ácidos Micólicos/isolamento & purificação , Parede Celular/química , Parede Celular/metabolismo , Cromatografia em Camada Fina , Corynebacterium glutamicum/química , Corynebacterium glutamicum/crescimento & desenvolvimento , Estrutura Molecular , Ácidos Micólicos/metabolismo , Espectrometria de Massas por Ionização por Electrospray
9.
J Chromatogr B Analyt Technol Biomed Life Sci ; 879(26): 2821-6, 2011 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-21871846

RESUMO

The profile of mycolic acids from Mycobacterium confluentis has not been adequately published. However, the definition of the composition of mycolic acids is a critical element for describing new mycobacterial species. Thus, an erroneously published profile can lead to confusing citations. The aim of this article is to make the protocols clear, by using thin layer chromatography as a tool, for defining the discrete pattern of mycolic acids of any newly reported mycobacterial species. By using this method, and corroborated using nuclear magnetic resonance analysis, we demonstrated that M. confluentis contains α-mycolates (type I) and epoxymycolates (type V mycolic acids).


Assuntos
Cromatografia em Camada Fina/métodos , Mycobacterium/química , Ácidos Micólicos/isolamento & purificação , Espectroscopia de Ressonância Magnética , Mycobacterium/metabolismo , Ácidos Micólicos/química , Ácidos Micólicos/metabolismo , Especificidade da Espécie
10.
J Microbiol Methods ; 80(3): 302-5, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20079769

RESUMO

A unique hydrolysis method using a two-layer solution, consisting of diluted hydrochloric acid and toluene was developed to isolate whole arabinose mycolates from the cell wall skeleton of Mycobacterium bovis BCG Tokyo 172 (SMP-105) in order to reveal its pivotal role in enhancing immune responses against tumors.


Assuntos
Arabinose/análogos & derivados , Esqueleto da Parede Celular/química , Mycobacterium bovis/química , Ácidos Micólicos , Adjuvantes Imunológicos/química , Arabinose/química , Ácido Clorídrico/química , Hidrólise , Estrutura Molecular , Ácidos Micólicos/química , Ácidos Micólicos/isolamento & purificação , Tóquio , Tolueno/química
11.
Pneumonol Alergol Pol ; 77(6): 517-20, 2009.
Artigo em Polonês | MEDLINE | ID: mdl-20013701

RESUMO

INTRODUCTION: The GenoType system (HAIN Lifescience, Germany) offers new perspectives of detecting the tuberculous and non-tuberculous mycobacteria at the molecular level. The system compromises five independent tests that could be performed either on direct specimens or isolated strains, to identify the strains and test the resistance against rifampin and isoniazid. Up to now, non GenoType test was applied in Poland. The aim of the study was an evaluation the accuracy of GenoType MTBC test in speciation of the clinical isolates, previously classified as M. tuberculosis complex by HPLC analyze of mycolic acids. MATERIAL AND METHODS: 161 clinical isolates, derived from the TB patients hospitalized in the Warsaw Medical University Hospital between 1999 and 2007 were assayed. RESULTS: On the basis of the hybridization patterns, all 161 studied strains were identified as M. tuberculosis/M. canettii. CONCLUSIONS: 1. The GenoType MTBC test (HAIN Lifescience, Germany) precisely recognizes M. tuberculosis complex. The 100% accordance in speciation of M. tuberculosis by the GenoType MTBC test as compared to HPLC method was demonstrated. The GenoType MTBC test can replace HPLC in detection of tuberculous mycobacteria in clinical isolates. 2. As the GenoType MTBC test performs well, the other tests of GenoType system may be considered to be verified in diagnostic procedure of mycobacterial infection.


Assuntos
Mycobacterium tuberculosis/isolamento & purificação , Hibridização de Ácido Nucleico/métodos , Tuberculose/diagnóstico , Tuberculose/microbiologia , Proteínas de Bactérias , Cromatografia Líquida de Alta Pressão , Genótipo , Humanos , Ácidos Micólicos/isolamento & purificação , Fragmentos de Peptídeos , Especificidade da Espécie
12.
J Microbiol Methods ; 72(2): 149-56, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18178279

RESUMO

The mycobacterial cell envelope consists of a characteristic cell wall skeleton (CWS), a mycoloyl arabinogalactan peptidoglycan complex, and related hydrophobic components that contribute to the cell surface properties. Since mycolic acids have recently been reported to play crucial roles in host immune response, detailed molecular characterization of mycolic acid subclasses and sub-subclasses of CWS from Mycobacterium bovis BCG Tokyo 172 (SMP-105) was performed. Mycolic acids were liberated by alkali hydrolysis from SMP-105, and their methyl esters were separated by silica gel TLC into three subclasses: alpha-, methoxy-, and keto-mycolates. Each mycolate subclass was further separated by silver nitrate (AgNO(3))-coated silica gel TLC into sub-subclasses. Molecular weights of individual mycolic acid were determined by MALDI-TOF mass spectrometry. alpha-Mycolates were sub-grouped into cis, cis-dicyclopropanoic (alpha1), and cis-monocyclopropanoic-cis-monoenoic (alpha2) series; methoxy-mycolates were sub-grouped into cis-monocyclopropanoic (m1), trans-monocyclopropanoic (m2), trans-monoenoic (m3), cis-monocyclopropanoic-trans-monoenoic (m4), cis-monoenoic (m5), and cis-monocyclopropanoic-cis-monoenoic (m6) series; and keto-mycolates were sub-grouped into cis-monocyclopropanoic (k1), trans-monocyclopropanoic (k2), trans-monoenoic (k3), cis-monoenoic (k4), and cis-monocyclopropanoic-cis-monoenoic (k5) series. The position of each functional group, including cyclopropane rings and methoxy and keto groups, was determined by analysis of the meromycolates with fast atom bombardment (FAB) mass spectrometry and FAB mass-mass spectrometry, and the cis/trans ratio of cyclopropane rings and double bonds were determined by NMR analysis of methyl mycolates. Mycolic acid subclass and molecular species composition of SMP-105 showed characteristic features including newly-identified cis-monocyclopropanoic-trans-monoenoic mycolic acid (m4).


Assuntos
Esqueleto da Parede Celular/química , Mycobacterium bovis/química , Ácidos Micólicos/química , Esqueleto da Parede Celular/isolamento & purificação , Cromatografia em Camada Fina , Hidrogênio/metabolismo , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Estrutura Molecular , Ácidos Micólicos/isolamento & purificação , Sílica Gel , Dióxido de Silício/análise , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
13.
J Biol Chem ; 283(3): 1419-1427, 2008 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-18006503

RESUMO

Mycolic acids are major and specific lipid components of the cell envelope of mycobacteria that include the causative agents of tuberculosis and leprosy, Mycobacterium tuberculosis and Mycobacterium leprae, respectively. Subtle structural variations that are known to be crucial for both their virulence and the permeability of their cell envelope occur in mycolic acids. Among these are the introduction of cyclopropyl groups and methyl branches by mycolic acid S-adenosylmethionine-dependent methyltransferases (MA-MTs). While the functions of seven of the M. tuberculosis MA-MTs have been either established or strongly presumed nothing is known of the roles of the remaining umaA gene product and those of M. smegmatis MA-MTs. Mutants of the M. tuberculosis umaA gene and its putative M. smegmatis orthologue, MSMEG0913, were created. The lipid extracts of the resulting mutants were analyzed in detail using a combination of analytical techniques such as matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and proton nuclear magnetic resonance spectroscopy, and chemical degradation methods. The M. smegmatis mutants no longer synthesized subtypes of mycolates containing a methyl branch adjacent to either trans cyclopropyl group or trans double bond at the "proximal" position of both alpha- and epoxy-mycolates. Complementation with MSMEG0913, but not with umaA, fully restored the wild-type phenotype in M. smegmatis. Consistently, no modification was observed in the structures of mycolic acids produced by the M. tuberculosis umaA mutant. These data proved that despite their synteny and high similarity umaA and MSMEG0913 are not functionally orthologous.


Assuntos
Proteínas de Bactérias/metabolismo , Metiltransferases/metabolismo , Mycobacterium smegmatis/enzimologia , Mycobacterium tuberculosis/enzimologia , Ativação Enzimática , Compostos de Epóxi/isolamento & purificação , Ésteres/isolamento & purificação , Teste de Complementação Genética , Espectroscopia de Ressonância Magnética , Mutação/genética , Ácidos Micólicos/química , Ácidos Micólicos/classificação , Ácidos Micólicos/isolamento & purificação , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
14.
Curr Protoc Microbiol ; Chapter 10: Unit 10A.3, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18770604

RESUMO

Mycolic acids are an important constituent of the mycobacterial cell wall. Changes in the structure or composition of mycolic acids have been associated with modification of cell wall permeability and attenuation of pathogenic Mycobacterium tuberculosis strains. This unit describes the isolation of M. tuberculosis mycolic acids and their analysis by either thin-layer chromatography or high-performance liquid chromatography. Both techniques have been extensively used to study (1) mycolic acid biosynthesis, (2) the role of mycolic acids in mycobacterial virulence, (3) the effect of antituberculosis drugs targeting the cell wall, and (4) taxonomic purposes.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Cromatografia em Camada Fina/métodos , Mycobacterium tuberculosis/química , Ácidos Micólicos/análise , Ácidos Micólicos/isolamento & purificação , Técnicas Bacteriológicas , Parede Celular/química , Humanos , Mycobacterium tuberculosis/classificação , Mycobacterium tuberculosis/metabolismo , Ácidos Micólicos/química
15.
Int J Syst Evol Microbiol ; 55(Pt 3): 1139-1147, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15879246

RESUMO

A group of slowly growing photochromogenic mycobacteria was isolated from Chesapeake Bay striped bass (Morone saxatilis) during an epizootic of mycobacteriosis. Growth characteristics, acid-fastness and 16S rRNA gene sequencing results were consistent with those of the genus Mycobacterium. Biochemical reactions, growth characteristics and mycolic acid profiles (HPLC) resembled those of Mycobacterium shottsii, a non-pigmented mycobacterium also isolated during the same epizootic. Sequencing of the 16S rRNA genes, the gene encoding the exported repeated protein (erp) and the gene encoding the 65 kDa heat-shock protein (hsp65) and restriction enzyme analysis of the hsp65 gene demonstrated that this group of isolates is unique. Insertion sequences associated with Mycobacterium ulcerans, IS2404 and IS2606, were detected by PCR. These isolates could be differentiated from other slowly growing pigmented mycobacteria by their inability to grow at 37 degrees C, production of niacin and urease, absence of nitrate reductase, negative Tween 80 hydrolysis and resistance to isoniazid (1 mug ml(-1)), p-nitrobenzoic acid, thiacetazone and thiophene-2-carboxylic hydrazide. On the basis of this polyphasic study, it is proposed that these isolates represent a novel species, Mycobacterium pseudoshottsii sp. nov. The type strain, L15(T), has been deposited in the American Type Culture Collection as ATCC BAA-883(T) and the National Collection of Type Cultures (UK) as NCTC 13318(T).


Assuntos
Bass/microbiologia , Mycobacterium/classificação , Mycobacterium/isolamento & purificação , Animais , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Técnicas de Tipagem Bacteriana , Chaperonina 60 , Chaperoninas/genética , Elementos de DNA Transponíveis , DNA Bacteriano/química , DNA Bacteriano/isolamento & purificação , DNA Ribossômico/química , DNA Ribossômico/isolamento & purificação , Genes de RNAr , Dados de Sequência Molecular , Mycobacterium/fisiologia , Ácidos Micólicos/análise , Ácidos Micólicos/isolamento & purificação , Filogenia , Polimorfismo de Fragmento de Restrição , RNA Bacteriano/genética , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Virginia
16.
Antonie Van Leeuwenhoek ; 87(2): 149-53, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15723176

RESUMO

The bacterial strain J3 was isolated from soil by selective enrichment on mineral medium containing 4-nitrocatechol as the sole carbon and energy source. This strain was identified as Rhodococcus wratislaviensis on the basis of morphology, biochemical, physiological and chemotaxonomic characterization and complete sequencing of the 16S rDNA gene. The isolated bacterium could utilize 4-nitrocatechol, 3-nitrophenol and 5-nitroguaiacol as sole carbon and energy sources. Stoichiometric release of nitrites was measured during degradation of 4-nitrocatechol both in growing cultures and for stationary phase cells. The J3 strain was unable to degrade 4-nitroguaiacol, 2-nitrophenol, 4-nitrophenol, 2,4-dinitrobenzoic acid, 4,5-dimethoxy-2-nitrobenzoic acid and 2,3-difluoro-6-nitrophenol. The J3 strain is deposited in the Czech Collection of Microorganisms as CCM 4930.


Assuntos
Catecóis/metabolismo , Nitrocompostos/metabolismo , Nitrofenóis/metabolismo , Rhodococcus/classificação , Rhodococcus/metabolismo , Técnicas de Tipagem Bacteriana , DNA Bacteriano/química , DNA Bacteriano/isolamento & purificação , DNA Ribossômico/química , DNA Ribossômico/isolamento & purificação , Ácidos Graxos/análise , Ácidos Graxos/isolamento & purificação , Genes de RNAr , Dados de Sequência Molecular , Ácidos Micólicos/análise , Ácidos Micólicos/isolamento & purificação , Nitritos/análise , Nitritos/metabolismo , Filogenia , RNA Bacteriano/genética , RNA Ribossômico 16S/genética , Rhodococcus/isolamento & purificação , Análise de Sequência de DNA , Microbiologia do Solo
17.
Syst Appl Microbiol ; 27(6): 653-60, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15612622

RESUMO

Mycobacterium strain FA4T was isolated with fluoranthene as the single carbon source from soil of a former coal gas plant, polluted with polycyclic aromatic hydrocarbons. The physiological properties, fatty acid pattern, and the 16S ribosomal RNA gene sequence indicated membership to the genus Mycobacterium, but were different from all type strains of Mycobacterium species. Based on comparative 16S rRNA gene sequence analyses strain FA4T could be assigned to the Mycobacterium neoaurum taxon showing 98% sequence similarity to M. diernhoferi as its closest neighbour. The occurrence of epoxymycolate in the cell wall differentiates FA4 from all members of this taxon which synthesize wax-ester mycolates in addition to alpha-mycolates. Strain FA4T is able to degrade aflatoxin B1. This biological attribute might be useful in biological detoxification processes of foods and feeds. From the investigated characteristics it is concluded that strain FA4T represents a new species, for which we propose the name Mycobacterium fluoranthenivorans sp. nov. The type strain of Mycobacterium fluoranthenivorans is FA4T (DSM 44556T = CIP 108203T).


Assuntos
Aflatoxina B1/metabolismo , Fluorenos/metabolismo , Mycobacterium/classificação , Mycobacterium/isolamento & purificação , Hidrocarbonetos Policíclicos Aromáticos , Microbiologia do Solo , Poluentes do Solo , Técnicas de Tipagem Bacteriana , Biodegradação Ambiental , Parede Celular/química , DNA Bacteriano/química , DNA Bacteriano/isolamento & purificação , DNA Ribossômico/química , DNA Ribossômico/isolamento & purificação , Ácidos Graxos/análise , Ácidos Graxos/isolamento & purificação , Genes de RNAr , Dados de Sequência Molecular , Mycobacterium/metabolismo , Ácidos Micólicos/análise , Ácidos Micólicos/isolamento & purificação , Filogenia , RNA Bacteriano/genética , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
18.
Int J Syst Evol Microbiol ; 54(Pt 6): 2057-2060, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15545434

RESUMO

The characterization of a novel slowly growing, scotochromogenic Mycobacterium species is reported. This previously undescribed mycobacterial species was isolated from five different patients with symptomatic pulmonary infections. All isolates were acid-fast-positive and the mycolic acid profiles were unique and supported placement into the genus Mycobacterium. Phenotypic characteristics of each strain included optimal growth after 3 weeks at a temperature range of 30-35 degrees C, yellow pigmentation after incubation in the dark and production of a heat-stable catalase. The 16S rRNA gene and internal transcribed spacer 1 sequences were identical for all five strains, but distinct from all known mycobacterial species. Phylogenetic analysis based on the 16S rRNA gene sequence placed the novel species within the slowly growing mycobacteria group in close proximity to Mycobacterium malmoense, Mycobacterium avium, Mycobacterium kansasii and Mycobacterium scrofulaceum. These data support the conclusion that the related five described organisms represent a novel Mycobacterium species, for which the name Mycobacterium nebraskense sp. nov. is proposed, with the type strain UNMC-MY1349(T) (=ATCC BAA-837(T)=DSM 44803(T)).


Assuntos
Infecções por Mycobacterium/microbiologia , Mycobacterium/classificação , Mycobacterium/isolamento & purificação , Escarro/microbiologia , Catalase/análise , DNA Bacteriano/química , DNA Bacteriano/isolamento & purificação , DNA Ribossômico/química , DNA Ribossômico/isolamento & purificação , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/isolamento & purificação , Estabilidade Enzimática , Genes de RNAr , Humanos , Dados de Sequência Molecular , Mycobacterium/química , Mycobacterium/fisiologia , Mycobacterium avium/genética , Mycobacterium kansasii/genética , Mycobacterium scrofulaceum/genética , Ácidos Micólicos/análise , Ácidos Micólicos/isolamento & purificação , Filogenia , Pigmentos Biológicos/biossíntese , RNA Bacteriano/genética , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Temperatura
19.
Int J Syst Evol Microbiol ; 54(Pt 6): 2313-2317, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15545477

RESUMO

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.


Assuntos
Mycobacterium/classificação , Mycobacterium/isolamento & purificação , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Microbiologia do Solo , Técnicas de Tipagem Bacteriana , Biodegradação Ambiental , Impressões Digitais de DNA , DNA Bacteriano/química , DNA Bacteriano/isolamento & purificação , DNA Ribossômico/química , DNA Ribossômico/isolamento & purificação , DNA Espaçador Ribossômico/análise , Ácidos Graxos/análise , Ácidos Graxos/isolamento & purificação , Genes de RNAr , Alemanha , Dados de Sequência Molecular , Mycobacterium/genética , Mycobacterium/metabolismo , Ácidos Micólicos/análise , Ácidos Micólicos/isolamento & purificação , Filogenia , RNA Bacteriano/genética , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
20.
Int J Syst Evol Microbiol ; 54(Pt 6): 2385-2391, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15545488

RESUMO

Four isolates of a rapidly growing Mycobacterium species had a mycolic acid pattern similar to that of Mycobacterium smegmatis, as determined by HPLC analyses. Three of the isolates were from footbath drains and a sink at a nail salon located in Atlanta, GA, USA; the fourth was obtained from a granulomatous subdermal lesion of a female patient in Venezuela who was undergoing mesotherapy. By random amplified polymorphic DNA electrophoresis and PFGE of large restriction fragments, the three isolates from the nail salon were shown to be the same strain but different from the strain from the patient in Venezuela. Polymorphisms in regions of the rpoB, hsp65 and 16S rRNA genes that were shown to be useful for species identification matched for the two strains but were different from those of other Mycobacterium species. The 16S rRNA gene sequence placed the strains in a taxonomic group along with Mycobacterium frederiksbergense, Mycobacterium hodleri, Mycobacterium diernhoferi and Mycobacterium neoaurum. The strains produced a pale-yellow pigment when grown in the dark at the optimal temperature of 35 degrees C. Biochemical testing showed that the strains were positive for iron uptake, nitrate reduction and utilization of d-mannitol, d-xylose, iso-myo-inositol, l-arabinose, citrate and d-trehalose. The strains were negative for d-sorbitol utilization and production of niacin and 3-day arylsulfatase, although arylsulfatase activity was observed after 14 days. The isolates grew on MacConkey agar without crystal violet but not on media containing 5 % (w/v) NaCl or at 45 degrees C. They were susceptible to ciprofloxacin, amikacin, tobramycin, cefoxitin, clarithromycin, doxycycline, sulfamethoxazole and imipenem. The name Mycobacterium cosmeticum sp. nov. is proposed for this novel species; two strains, LTA-388(T) (=ATCC BAA-878(T)=CIP 108170(T)) (the type strain) and 2003-11-06 (=ATCC BAA-879=CIP 108169) have been designated, respectively, for the strains of the patient in Venezuela and from the nail salon in Atlanta, GA, USA.


Assuntos
Indústria da Beleza , Técnicas Cosméticas , Infecções por Mycobacterium/microbiologia , Mycobacterium/classificação , Mycobacterium/isolamento & purificação , Unhas , Dermatopatias Bacterianas/microbiologia , Proteínas de Bactérias/genética , Técnicas de Tipagem Bacteriana , Chaperonina 60 , Chaperoninas/genética , Impressões Digitais de DNA , DNA Bacteriano/química , DNA Bacteriano/isolamento & purificação , DNA Ribossômico/química , DNA Ribossômico/isolamento & purificação , RNA Polimerases Dirigidas por DNA/genética , Feminino , Genes de RNAr , Humanos , Injeções Subcutâneas , Microinjeções , Dados de Sequência Molecular , Mycobacterium/química , Mycobacterium/fisiologia , Ácidos Micólicos/análise , Ácidos Micólicos/isolamento & purificação , Hibridização de Ácido Nucleico , Filogenia , Pigmentos Biológicos/biossíntese , Polimorfismo Genético , Polimorfismo de Fragmento de Restrição , RNA Bacteriano/genética , RNA Ribossômico 16S/genética , Técnica de Amplificação ao Acaso de DNA Polimórfico , Análise de Sequência de DNA , Temperatura , Estados Unidos , Venezuela
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