Extracellular hemolytic activity in rapidly growing mycobacteria

1994 ◽  
Vol 40 (4) ◽  
pp. 318-321 ◽  
Author(s):  
Takezo Udou
Keyword(s):  
Hemolytic Activity ◽  
Mycobacterium Smegmatis ◽  
Culture Medium ◽  
Maximal Activity ◽  
Mycobacterium Fortuitum ◽  
Mycobacterium Chelonae ◽  
Rapidly Growing Mycobacteria ◽  
Factors Associated ◽  
Reference Strains

Little is known about virulence factors associated with rapidly growing mycobacteria. We evaluated 42 clinical isolates of Mycobacterium fortuitum and Mycobacterium chelonae and 4 reference strains of Mycobacterium smegmatis for the production of hemolysin (or hemolytic substance) as a possible contributor to the pathogenesis of disease caused by these organisms. All the strains tested possessed extracellular hemolytic activity that was stable after heating and proteinase treatment, and the active substance had a molecular weight less than 10 000. The activity accumulated in culture medium during the late exponential to mid stationary phase of growth. Hemolysis in vitro was relatively slow; incubation for 10 h at 35 °C was required to obtain maximal activity. Some specificity of the hemolysis with regard to red blood cells from different animals was observed.Key words: rapidly growing mycobacteria, Mycobacterium fortuitum, Mycobacterium chelonae, Mycobacterium smegmatis, hemolytic activity.

scholarly journals In Vitro Susceptibilities of Rapidly Growing Mycobacteria to Telithromycin (HMR 3647) and Seven Other Antimicrobials

2000 ◽  
Vol 44 (1) ◽  
pp. 181-182 ◽  
Author(s):  
Ricardo Fernández-Roblas ◽  
Jaime Esteban ◽  
Froilán Cabria ◽  
Juan Carlos López ◽  
Maria Soledad Jiménez ◽  
...  
Keyword(s):  
Antimicrobial Activities ◽  
Mycobacterium Abscessus ◽  
Mycobacterium Fortuitum ◽  
Mycobacterium Chelonae ◽  
Rapidly Growing Mycobacteria ◽  
Mycobacterium Mucogenicum

ABSTRACT The antimicrobial activities of telithromycin (HMR 3647) and seven other antimicrobials against 94 strains of rapidly growing mycobacteria were determined. Telithromycin at a concentration of 1 μg/ml inhibited Mycobacterium peregrinum (100%),Mycobacterium chelonae (80%), Mycobacterium abscessus-Mycobacterium mucogenicum (44.4%), andMycobacterium fortuitum (2.1%). All or most strains ofM. peregrinum, M. fortuitum, and M. mucogenicum were inhibited by 2 μg of quinolones per ml.

scholarly journals In Vitro Activities of Isepamicin, Other Aminoglycosides, and Capreomycin against Clinical Isolates of Rapidly Growing Mycobacteria in Taiwan

2007 ◽  
Vol 51 (5) ◽  
pp. 1849-1851 ◽  
Author(s):  
Gwan-Han Shen ◽  
Bo-Da Wu ◽  
Kun-Ming Wu ◽  
Jiann-Hwa Chen
Keyword(s):  
Clinical Isolates ◽  
Mycobacterium Fortuitum ◽  
Mycobacterium Chelonae ◽  
Rapidly Growing Mycobacteria

ABSTRACT The in vitro activities of isepamicin against 117 Mycobacteria abscessus, 48 Mycobacterium fortuitum, and 20 Mycobacterium chelonae isolates were evaluated by a microdilution test. Isepamicin MIC90s were ≤16 μg/ml for the three species. Isepamicin was as active as amikacin and kanamycin and more active than tobramycin, capreomycin, gentamicin, and streptomycin.

scholarly journals In Vitro Activities of Omadacycline against Rapidly Growing Mycobacteria

2019 ◽  
Vol 63 (5) ◽  
Author(s):  
Carolyn Shoen ◽  
David Benaroch ◽  
Mary Sklaney ◽  
Michael Cynamon
Keyword(s):  
Mycobacterium Abscessus ◽  
Mycobacterium Fortuitum ◽  
Mycobacterium Chelonae ◽  
Content Type ◽  
Rapidly Growing Mycobacteria ◽  
Dilution Assay ◽  
Tetracycline Derivative

ABSTRACT The in vitro activity of omadacycline, a new tetracycline derivative, was evaluated against isolates of Mycobacterium abscessus, Mycobacterium chelonae, and Mycobacterium fortuitum using a broth microtiter dilution assay. Omadacycline had MIC90 values of 2 μg/ml, 0.25 μg/ml, and 0.5 μg/ml, respectively. The in vitro activity of omadacycline against rapidly growing mycobacteria indicates that it may have the potential to improve therapy for infections caused by these organisms.

scholarly journals Comparison of In Vitro Activities of Gatifloxacin and Ciprofloxacin against Four Taxa of Rapidly Growing Mycobacteria

2002 ◽  
Vol 46 (10) ◽  
pp. 3283-3285 ◽  
Author(s):  
Barbara A. Brown-Elliott ◽  
Richard J. Wallace ◽  
Christopher J. Crist ◽  
Linda Mann ◽  
Rebecca W. Wilson
Keyword(s):  
Mycobacterium Fortuitum ◽  
Broth Microdilution ◽  
Mycobacterium Chelonae ◽  
Rapidly Growing Mycobacteria

ABSTRACT By using current NCCLS broth microdilution methods, we found that gatifloxacin inhibited 90% of the isolates of the Mycobacterium fortuitum group at ≤0.12 μg/ml and 90% of the Mycobacterium chelonae isolates at ≤4 μg/ml. Gatifloxacin was generally fourfold more active than ciprofloxacin. We recommend that both gatifloxacin and ciprofloxacin be tested routinely against rapidly growing mycobacteria.

scholarly journals Activities of the glycylcyclines N,N-dimethylglycylamido-minocycline and N,N-dimethylglycylamido-6-demethyl-6-deoxytetracycline against Nocardia spp. and tetracycline-resistant isolates of rapidly growing mycobacteria.

1996 ◽  
Vol 40 (4) ◽  
pp. 874-878 ◽  
Author(s):  
B A Brown ◽  
R J Wallace ◽  
G Onyi
Keyword(s):  
Therapeutic Potential ◽  
Sensu Stricto ◽  
Mycobacterium Abscessus ◽  
Mycobacterium Fortuitum ◽  
New Taxon ◽  
Mycobacterium Chelonae ◽  
New Agents ◽  
Rapidly Growing Mycobacteria ◽  
Nocardia Brasiliensis ◽  
Mycobacterium Mucogenicum

Susceptibilities to the new semisynthetic tetracycline (Tet) compounds N,N-dimethylglycylamido-minocycline (DMG-MINO) and N,N-dimethylglycylamido-6-demethyl-6-deoxytetracycline (DMG-DMDOT) were compared with those to doxycycline, minocycline, and Tet for 198 Tet-resistant (Tetr) and 33 Tet-susceptible (Tets) clinical isolates of rapidly growing mycobacteria (RGM) including the Mycobacterium fortuitum group, Mycobacterium abscessus, Mycobacterium chelonae, and Mycobacterium mucogenicum and 68 isolates belonging to six taxa of Nocardia spp. All Tetr RGM were highly susceptible to the glycylcyclines. The MICs at which 50 and 90% of isolates are inhibited were < or = 0.125 and < or = 0.25 microgram/ml, respectively, for DMG-DMDOT and < or = 0.25 and 1 microgram/ml, respectively, for DMG-MINO. The MIC of DMG-DMDOT at which 50% of Tetr strains are inhibited was the same as that for Tets strains for each of the four taxa of RGM. The new agents were less active against Nocardia spp. MICs of DMG-DMDOT were comparable to those of minocycline except for the MICs for Nocardia brasiliensis sensu stricto, the new taxon Nocardia pseudobrasiliensis, and some isolates of Nocardia nova, against which they were four- to eightfold more active. The MICs of DMG-DMDOT were consistently lower than those of DMG-MINO for RGM. This class of drugs offers exciting therapeutic potential for RGM and for selected species of Nocardia.

scholarly journals Role of Porins in the Susceptibility of Mycobacterium smegmatis and Mycobacterium chelonae to Aldehyde-Based Disinfectants and Drugs

2009 ◽  
Vol 53 (9) ◽  
pp. 4015-4018 ◽  
Author(s):  
Zuzana Svetlíková ◽  
Henrieta Škovierová ◽  
Michael Niederweis ◽  
Jean-Louis Gaillard ◽  
Gerald McDonnell ◽  
...  
Keyword(s):  
Mycobacterium Smegmatis ◽  
Resistant Bacteria ◽  
Clinical Settings ◽  
Drug Resistant ◽  
Mycobacterium Chelonae ◽  
Rapidly Growing Mycobacteria ◽  
Drug Resistant Bacteria

ABSTRACT 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.

Development of a nucleic acid chromatography assay for the detection of commonly isolated rapidly growing mycobacteria

2021 ◽  
Vol 70 (12) ◽  
Author(s):  
Yuriko Igarashi ◽  
Kinuyo Chikamatsu ◽  
Sotaro Sano ◽  
Shigehiko Miyamoto ◽  
Akio Aono ◽  
...  
Keyword(s):  
Nucleic Acid ◽  
Type Species ◽  
Target Genes ◽  
Mycobacterium Abscessus ◽  
Heat Denaturation ◽  
Mycobacterium Fortuitum ◽  
Mycobacterium Chelonae ◽  
Content Type ◽  
Rapidly Growing Mycobacteria ◽  
Link Type

Introduction. Non-tuberculosis mycobacterium infections are increasing worldwide, including those caused by rapidly growing mycobacteria (RGM). Gap Statement. The identification of the aetiological agent in the context of infections is essential for the adoption of an adequate therapeutic approach. However, the methods for the rapid distinction of different RGM species are less than optimal. Aim. To develop a nucleic acid chromatography kit to identify clinically common RGM. Methodology. We tried to develop a nucleic acid chromatography kit designed to detect four RGM species (including three subspecies) i.e. Mycobacterium abscessus subsp. abscessus , Mycobacterium abscessus subsp. bolletii (detected as M. abscessus/bolletii) Mycobacterium abscessus subsp. massiliense , Mycobacterium fortuitum , Mycobacterium chelonae and Mycobacterium peregrinum . The amplified target genes for each species/subspecies using multiplex PCR were analysed using a nucleic acid chromatography assay. Results. Among the 159 mycobacterial type strains and 70 RGM clinical isolates tested, the developed assay correctly identified all relevant RGM without any cross-reactivity or false-negatives. The limits of detection for each species were approximately 0.2 pg µl-1. Conclusion. The rapid and simple nucleic acid chromatography method developed here, which does not involve heat denaturation, may contribute to the rapid identification and treatment of RGM infections.

scholarly journals Regulation of in vitro somatic embryogenesis with emphasis on to the role of endogenous hormones

2001 ◽  
Vol 13 (2) ◽  
pp. 196-223 ◽  
Author(s):  
VÍCTOR M. JIMÉNEZ
Keyword(s):  
Somatic Embryogenesis ◽  
Plant Growth ◽  
Growth Regulators ◽  
Culture Medium ◽  
Endogenous Hormones ◽  
Tissue Cultures ◽  
Factors Associated ◽  
General Aspects

Different aspects of the in vitro somatic embryogenesis regulation are reviewed in this paper.work. A description of g General aspects, such as terminology, uses, stages of development and factors associated with the somatic embryogenesis, are described. is carried out. Although a brief description ofn the effects of the addition of different plant growth regulators to the culture medium wasis given, the article is centereds itself on the effect that the endogenous hormone concentrations in the initial explants and in the tissue cultures derived from them could play oin the induction and expression of somatic embryogenesis. It is significant that few to emphasize the low amount of systematic studies have been conducted, in this subject, in which different species and hormone groups were compared in cultures with and without embryogenic capacity. Moreover, the lack of correlation between the results presented in different studies the distinct works indicates that the hormone content of the cultures is not the only factor involved.

Intracellular Antimycobacterial Activity of Ciprofloxacin and Ofloxacin in Mycobacterium Fortuitum Infected Human Polymorphonuclear Leucocytes

1995 ◽  
Vol 8 (3) ◽  
pp. 209-215
Author(s):  
P. Nziramasanga ◽  
P.M. Shah ◽  
W. Stille
Keyword(s):  
Culture Medium ◽  
Brain Heart Infusion ◽  
Antimycobacterial Activity ◽  
Mycobacterium Fortuitum ◽  
Polymorphonuclear Leucocytes ◽  
Atypical Mycobacterium ◽  
Minimal Inhibitory Concentrations ◽  
Quinolone Antibiotics ◽  
Colony Forming Units

The broadspectrum quinolone antibiotics ciprofloxacin and ofloxacin were tested for activity against the atypical mycobacterium M.fortuitum. In vitro minimal inhibitory concentrations (MIC) were done in Brain Heart Infusion broth and intracellular determinations in Medium 199 cell culture medium. The PMNs with intracellular bacteria and controls with or without drugs were incubated for six hours at 37°C. Hourly, 0.1 ml aliquotes were taken for colony forming units (cfu) assays. In vitro and intracellular MIC's for ciprofloxacin were 0.125mg/l and 0.625 mg/l respectively, while for ofloxacin they were 0.2mg/l and 0.4 mg/l, respectively.

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