Cholesterol is accumulated by mycobacteria but its degradation is limited to non-pathogenic fast-growing mycobacteria

2000 ◽  
Vol 46 (9) ◽  
pp. 826-831 ◽  
Author(s):  
Yossef Av-Gay ◽  
Rafat Sobouti
Keyword(s):  
Mycobacterium Tuberculosis ◽  
Carbon Source ◽  
Sole Carbon Source ◽  
Mycobacterial Infection ◽  
Growth Media ◽  
Bacillus Calmette Guerin ◽  
Liquid Media ◽  
Fast Growing ◽  
Solid Media ◽  
Slow Growing

In this report we show that fast-growing non-pathogenic mycobacteria degrade cholesterol from liquid media, and are able to grow on cholesterol as a sole carbon source. In contrast, slow-growing mycobacteria, including pathogenic Mycobacterium tuberculosis and bacillus Calmette-Guérin (BCG), do not degrade and use cholesterol as a carbon source. Nevertheless, pathogenic mycobacteria are able to uptake, modify, and accumulate cholesterol from liquid growth media, and form a zone of clearance around a colony when plated on solid media containing cholesterol. These data suggest that cholesterol may have a role in mycobacterial infection other than its use as carbon source.Key words: mycobacteria, cholesterol, biodegradation.

scholarly journals Sugarcane bagasse as a source of carbon for enzyme production by filamentous fungi1

Hoehnea ◽  
2018 ◽  
Vol 45 (1) ◽  
pp. 134-142 ◽  
Author(s):  
Flaviane Lopes Ferreira ◽  
Cesar Barretta Dall'Antonia ◽  
Emerson Andrade Shiga ◽  
Larissa Juliani Alvim ◽  
Rosemeire Aparecida Bom Pessoni
Keyword(s):  
Carbon Source ◽  
Enzymatic Activity ◽  
Sugarcane Bagasse ◽  
Enzyme Production ◽  
Sole Carbon Source ◽  
Sole Source ◽  
Maximum Activity ◽  
Liquid Media ◽  
Biotechnological Potential ◽  
Efficient Producer

ABSTRACT The aim of the present work was to assess the enzymatic activity of six strains of filamentous fungi grown in liquid media containing 1% sugarcane bagasse as the sole carbon source. All fungal strains were able to use this agro-industrial residue, producing various types of enzymes, such as cellulases, xylanases, amylases, pectinases, and laccases. However, Aspergillus japonicus Saito was the most efficient producer, showing the highest enzymatic activity for laccase (395.73 U L-1), endo-β-1,4-xylanase (3.55 U mL-1) and β-xylosidase (9.74 U mL-1) at seven, fourteen and twenty-one days in culture, respectively. Furthermore, the endo-β-1,4-xylanases and β-xylosidases of A. japonicus showed maximum activity at 50°C, and pH 5.5 and pH 3.5-4.5, respectively. Thus, these results indicate that A. japonicus has a great biotechnological potential for the production of these enzymes using sugarcane bagasse as the sole source of carbon.

scholarly journals Mycobacterium tuberculosis Is Able To Accumulate and Utilize Cholesterol

2009 ◽  
Vol 191 (21) ◽  
pp. 6584-6591 ◽  
Author(s):  
Anna Brzostek ◽  
Jakub Pawelczyk ◽  
Anna Rumijowska-Galewicz ◽  
Bozena Dziadek ◽  
Jaroslaw Dziadek
Keyword(s):  
Cell Wall ◽  
Mycobacterium Tuberculosis ◽  
Carbon Source ◽  
Sole Carbon Source ◽  
Cytoplasmic Membrane ◽  
Degradation Pathway ◽  
Cholesterol Accumulation ◽  
Targeted Disruption ◽  
Future Studies

ABSTRACT It is expected that the obligatory human pathogen Mycobacterium tuberculosis must adapt metabolically to the various nutrients available during its cycle of infection, persistence, and reactivation. Cholesterol, which is an important part of the mammalian cytoplasmic membrane, is a potential energy source. Here, we show that M. tuberculosis grown in medium containing a carbon source other than cholesterol is able to accumulate cholesterol in the free-lipid zone of its cell wall. This cholesterol accumulation decreases the permeability of the cell wall for the primary antituberculosis drug, rifampin, and partially masks the mycobacterial surface antigens. Furthermore, M. tuberculosis was able to grow on mineral medium supplemented with cholesterol as the sole carbon source. Targeted disruption of the Rv3537 (kstD) gene inhibited growth due to inactivation of the cholesterol degradation pathway, as evidenced by accumulation of the intermediate, 9-hydroxy-4-androstene-3,17-dione. Our findings that M. tuberculosis is able to accumulate cholesterol in the presence of alternative nutrients and use it when cholesterol is the sole carbon source in vitro may facilitate future studies into the pathophysiology of this important deadly pathogen.

scholarly journals Effect of Lactose on Soluble-glucan Production and on the Ultrastructure of Sclerotium rolfsii Sacc. Grown in Submerged Culture

Microbiology ◽  
2000 ◽  
Vol 81 (1) ◽  
pp. 145-149 ◽  
Author(s):  
Y. Okon ◽  
I. Chet ◽  
Naomi Kislev ◽  
Y. Henis
Keyword(s):  
Carbon Source ◽  
Submerged Culture ◽  
Sole Carbon Source ◽  
Synthetic Medium ◽  
Sclerotium Rolfsii ◽  
Dry Weight ◽  
Solid Media

SUMMARY A significant increase in mycelial dry weight and a decrease in production of extracellular glucan were observed when lactose was added to a submerged culture of Sclerotium rolfsii grown in a liquid glucose-synthetic medium. When added as a sole carbon source, lactose at 2·5% (w/v) induced the formation of dark, spherical, compact bodies. The ultrastructure of these bodies is compared with that of sclerotia formed on solid media.

Immunobiology of Pediatric Tuberculosis: Lessons Learned and Implications for an Improved TB-Vaccine

2017 ◽  
Vol 13 (02) ◽  
pp. 113-121 ◽  
Author(s):  
Mardi Boer ◽  
Deborah Lewinsohn ◽  
Christina Lancioni
Keyword(s):  
Mycobacterium Tuberculosis ◽  
Immune Responses ◽  
Mycobacterial Infection ◽  
Lessons Learned ◽  
Bacillus Calmette Guerin ◽  
Partial Protection ◽  
Young Infants ◽  
Pediatric Tb ◽  
Pediatric Tuberculosis ◽  
Disseminated Disease

AbstractChildren, especially neonates and young infants, are uniquely vulnerable to tuberculosis (TB) and frequently present with primary progressive pulmonary or disseminated disease. There is an urgent need to understand the unique immunobiology of Mycobacterium tuberculosis (Mtb) in young infants and to identify protective infant immune responses. The existing vaccine against TB, Mycobacterium bovis bacillus Calmette–Guérin (M. bovis BCG), provides a partial protection against TB disease and disseminated forms of TB in infants; however, it is unknown how this partial protection is mediated. To end pediatric TB morbidity and mortality, a fully efficacious next-generation TB-vaccine is needed. Here, we focus on our current understanding of TB immunobiology as it pertains to young infants, and we evaluate what BCG-vaccination, as well as recently trialed novel TB-vaccines, has taught us about the immunobiology of mycobacterial infection in this population.

Acidobacteria from oligotrophic soil from the Cerrado can grow in a wide range of carbon source concentrations

2013 ◽  
Vol 59 (11) ◽  
pp. 746-753 ◽  
Author(s):  
Virgilio Hipólito Lemos de Castro ◽  
Luis Felipe Schroeder ◽  
Betania Ferraz Quirino ◽  
Ricardo Henrique Kruger ◽  
Cristine Chaves Barreto
Keyword(s):  
Carbon Source ◽  
16S Rrna ◽  
Growth Rates ◽  
Carboxymethyl Cellulose ◽  
Sole Carbon Source ◽  
Solid Medium ◽  
Colloidal Chitin ◽  
Brazilian Cerrado ◽  
Liquid Media ◽  
Wide Range

Soils from the Brazilian Cerrado are nutrient-poor, acidic, and aluminum-rich. A previous study revealed that members of the phylum Acidobacteria were predominant in these oligotrophic soils. Five acidobacteria from Cerrado soil were isolated on VL-55 medium containing 0.05% of xylan as carbon source. All isolates belong to the Acidobacteria subdivision 1, and their 16S rRNA showed similarities of 94.2%–96% with Acidobacterium capsulatum or 98.6% with Edaphobacter aggregans. All isolates were able to sustain growth in a wide range of carbon source concentrations. Growth occurred in all concentrations of arabinose, dextrose, and xylose; only one isolate did not grow on fructose. Isolates grew poorly on N-acetyl-d-glucosamine at all concentrations tested. In general, increasing concentrations of these monosaccharides did not inhibit growth rates. Isolates exhibited growth on solid medium containing xylan, carboxymethyl cellulose, and colloidal chitin; however, growth was observed on solid medium that did not contain these polysaccharides. These isolates may be able to use the solidifying agents tested (gellan gum or agar) as carbon source. This interpretation is supported by the absence of growth in liquid media containing chitin or carboxymethyl cellulose at 0.05% as sole carbon source, whereas growth in the same conditions using xylan was confirmed.

scholarly journals Oxadiazoles Have Butyrate-Specific Conditional Activity against Mycobacterium tuberculosis

2016 ◽  
Vol 60 (6) ◽  
pp. 3608-3616 ◽  
Author(s):  
Julie V. Early ◽  
Allen Casey ◽  
Maria Angeles Martinez-Grau ◽  
Isabel C. Gonzalez Valcarcel ◽  
Michal Vieth ◽  
...  
Keyword(s):  
Mycobacterium Tuberculosis ◽  
Carbon Source ◽  
Mammalian Cells ◽  
Sole Carbon Source ◽  
Specific Activity ◽  
Antitubercular Activity ◽  
Content Type ◽  
Phenotypic Screen

Mycobacterium tuberculosisis 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 againstM. tuberculosisgrown with butyrate but not with glucose as the carbon source. Among the hits, we identified an oxadiazole series (six compounds) which had specific activity againstM. tuberculosisbut which lacked cytotoxicity against mammalian cells.

Metabolism of p- and m-xylene by species of Pseudomonas

1968 ◽  
Vol 14 (9) ◽  
pp. 1005-1009 ◽  
Author(s):  
R. S. Davis ◽  
F. E. Hossler ◽  
R. W. Stone
Keyword(s):  
Carbon Source ◽  
Growth Medium ◽  
Oxidative Metabolism ◽  
Sole Carbon Source ◽  
Growth Media ◽  
Toluic Acids

Species of Pseudomonas isolated from soil could utilize m- or p-xylene as the sole carbon source. The respective toluic acids of the xylenes were isolated from growth media and from cells suspended in buffer. Cells grown on either hydrocarbon were capable of "meta" type cleavage of catechol and the methylcatechols. A compound whose properties were consistent with the structure of 2-hydroxy-5-methylmuconic semialdehyde was produced when cell-free extracts of p-xylene-grown cells were confronted with 4-methylcatechol. This muconic semialdehyde was present in the growth medium of p-xylene-grown cells and in buffer suspensions of these cells confronted with p-xylene. Paraxylene-grown cells oxidized p-chlorotoluene and 4-chloro-catechol to a compound with a spectrum similar to those of "meta" cleavage products. Chemical isolations and manometric data are consistent with a pathway for the oxidative metabolism of p-xylene which includes p-methylbenzyl alcohol, p-tolualdehyde, p-toluic acid, 4-methylcatechol, and 2-hydroxy-5-methylmuconic semialdehyde.

scholarly journals Characterization of differentially detectable Mycobacterium tuberculosis in the sputum of subjects with drug sensitive or drug resistant tuberculosis before and after two months of therapy

2021 ◽  
Author(s):  
Kayvan Zainabadi ◽  
Kathleen Frances Walsh ◽  
Stalz Charles Vilbrun ◽  
Laurent Daniel Mathurin ◽  
Myung Hee Lee ◽  
...  
Keyword(s):  
Mycobacterium Tuberculosis ◽  
Drug Resistant ◽  
Second Line ◽  
Liquid Media ◽  
Treatment Regimens ◽  
Resistant Tuberculosis ◽  
Solid Media ◽  
Large Populations ◽  
Before And After

Standard methods for enumerating Mycobacterium tuberculosis (Mtb) in patient sputa can miss large populations of viable Mtb that are unable to grow either on solid media or in liquid media if not extensively diluted. Because these bacteria can be detected in liquid media after limiting dilution, they have been termed differentially culturable or differentially detectable Mtb (DD Mtb). Treatment with isoniazid, rifampin, pyrazinamide and ethambutol (HRZE) for 1-2 weeks has been shown to increase the representation of DD Mtb in the sputum of drug sensitive (DS) tuberculosis (TB) patients. However, little is known about DD Mtb after longer periods of treatment with HRZE, or in patients with drug resistant (DR) TB who receive second-line therapies. Here we measured the proportion of DD Mtb in the sputum of 47 subjects, 29 with DS TB and 18 with DR TB, before initiation of their treatment regimens and at 2 weeks and 2 months thereafter. Prior to treatment, DD Mtb represented the majority of Mtb in the sputum of 21% of subjects with DS TB and this proportion rose to 65% after 2 weeks of treatment with first-line drugs. In subjects with DR TB, DD Mtb was found in the sputum of 29% of subjects prior to treatment initiation, and this proportion remained steady at 31% after 2 weeks of treatment with second-line drugs. By 2 months, DD Mtb was detected in the sputum of only 2/15 (13.3%) subjects with DS TB and 0/15 of subjects with DR TB. One of the DS subjects whose sputum was positive for DD Mtb at month 2 later experienced treatment failure.

Sensitivity of Rhizobium to selected isoflavonoids

1980 ◽  
Vol 26 (4) ◽  
pp. 542-545 ◽  
Author(s):  
C. E. Pankhurst ◽  
D. R. Biggs
Keyword(s):  
Effective Dose ◽  
Inhibitory Activity ◽  
Soft Agar ◽  
Biochanin A ◽  
Liquid Media ◽  
Fast Growing ◽  
Rhizobium Strains ◽  
Slow Growing

Eleven isoflavonoids were tested in both soft agar and liquid media for inhibitory activity against eight Rhizobium strains. Results of the two bioassays showed that pisatin, coumestrol, biochanin A, formononetin, genistein, rotenone, and vestitol lacked significant inhibitory activity. Phaseollin and maackiain were moderately inhibitory (ED50 (mean effective dose) = 30–100 μg/mL), and medicarpin and kievitone were strongly inhibitory (ED50 = 10–60 μg/mL) towards slow-growing R. japonicum and R. lupini and also towards two fast-growing Lotus rhizobia. In contrast, R. trifolii, R. leguminosarum, and R. phaseoli were not affected by these compounds (ED50 > 100 μg/mL), and R. meliloti was inhibited only by kievitone (ED50 = 30–60 μg/mL). At a concentration of 100 μg/mL, medicarpin and kievitone were found to be bactericidal to R. japonicum, R. lupini, and the fast-growing Lotus rhizobia.

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