Cytolytic leukotoxins of the repeat in toxin (RTX) family are large proteins excreted by gram-negative bacterial pathogens through the type 1 secretion system (T1SS). Due to low yields and poor stability in cultures of the original pathogens, it is useful to purify recombinant fatty-acylated RTX cytolysins from inclusion bodies produced in E. coli. Such preparations are, however, typically contaminated by high amounts of E. coli lipopolysaccharide (LPS or endotoxin). We report a simple procedure for purification of large amounts of biologically active and endotoxin-free RTX toxins. It is based on the common feature of RTX cytolysins that are T1SS-excreted as unfolded polypeptides and fold into a biologically active toxin only upon binding of calcium ions outside of the bacterial cell. Mimicking this process, the RTX proteins are solubilized from inclusion bodies with buffered 8 M urea, bound onto a suitable chromatographic medium under denaturing conditions and the contaminating LPS is removed through extensive on-column washes with buffers containing 6 to 8 M urea and 1% Triton X-100 or Triton X-114. Extensive on-column rinsing with 8 M urea buffer removes residual detergent and the eluted highly active RTX protein preparations then contain only trace amounts of LPS. The procedure is exemplified using four prototypic RTX cytolysins, the Bordetella pertussis CyaA and the hemolysins of Escherichia coli (HlyA), Kingella kingae (RtxA), and Actinobacillus pleuropneumoniae (ApxIA).
- MeSH
- bakteriální proteiny izolace a purifikace toxicita MeSH
- cytotoxiny izolace a purifikace toxicita MeSH
- detergenty chemie MeSH
- erytrocyty účinky léků MeSH
- Escherichia coli metabolismus MeSH
- hemolýza MeSH
- hemolyziny izolace a purifikace toxicita MeSH
- lidé MeSH
- lipopolysacharidy analýza MeSH
- močovina chemie MeSH
- nádorové buněčné linie MeSH
- oktoxynol chemie MeSH
- ovce MeSH
- THP-1 buňky MeSH
- viabilita buněk účinky léků MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
The aim of the present study was to determine effect of two decellularized agents, sodium dodecyl sulphate (SDS) and Triton X-100, to the skeletal muscle tissue. Final scaffold was evaluated by several histological techniques to analyse preservation of essential structures including collagen and elastic fibres, basement membranes, glycosaminoglycans and also to confirm elimination of nuclear and cytoplasmic components which are redundant in effectively prepared decellularized scaffolds. Comparison of tissue scaffolds processed with different detergents proved that SDS is superior to Triton X-100 as it can effectively decellularize muscle tissue.
- MeSH
- barvicí látky MeSH
- dodecylsíran sodný farmakologie MeSH
- elastická tkáň diagnostické zobrazování účinky léků MeSH
- glykosaminoglykany MeSH
- kolagen účinky léků MeSH
- kosterní svaly cytologie účinky léků MeSH
- mikroskopie MeSH
- myši MeSH
- oktoxynol farmakologie MeSH
- povrchově aktivní látky farmakologie MeSH
- tkáňové podpůrné struktury * MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Mucin-associated microbiota are in relatively close contact with the intestinal epithelium and may thus have a more pronounced effect on host health. We have previously developed a simple mucin agar assay to simulate initial mucus colonization by intestinal microbial communities. Adherence of microbiota was estimated using flow cytometry after detachment with Triton X-100. In this study, the effect of this detergent on the cultivability of both virulent and commensal strains was investigated. Mucin attachment of selected strains was evaluated using the mucin adhesion assay. Bacteria were dislodged from the mucin surface by incubation with Triton or from the whole mucin agar layer using a stomacher. Mechanical extraction resulted in 1.24 ± 0.42, 2.69 ± 0.44, and 1.56 ± 0.85 log CFU/mL higher plate counts of Lactobacillus rhamnosus, Bacillus cereus, and Escherichia coli strains, respectively, than the chemical method. The sensitivity of bacteria to Triton varied among microbial species and strains. Among others, Triton inhibited the growth of Salmonella enterica LMG 10396 and Pseudomonas aeruginosa LMG 8029 on laboratory media, although these bacteria maintained their viability during this treatment. Only Gram-positive strains, Enterococcus hirae LMG 6399 and L. rhamnosus GG, were not affected by this detergent. Therefore, the mechanical method is recommended for the extraction of mucin-adhered bacteria that are sensitive to Triton, especially when followed by traditional cultivation techniques. However, this approach can also be recommended for strains that are not affected by this detergent, because it resulted in higher recovery of adhered L. rhamnosus GG compared to the chemical extraction.
- MeSH
- Bacteria účinky léků růst a vývoj MeSH
- bakteriální adheze účinky léků MeSH
- biotest MeSH
- detergenty farmakologie MeSH
- muciny chemie MeSH
- oktoxynol farmakologie MeSH
- prasata MeSH
- střevní sliznice mikrobiologie MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Trichomonas vaginalis has been reported to possess alternative 2-keto acid oxidoreductases (KORs). These enzymes preferentially used indolepyruvate in a reaction that resembled that of pyruvate:ferredoxin oxidoreductase (PFO). However, the KORs did not reduce ferredoxin and remained active in metronidazole-resistant trichomonads lacking PFO. Therefore, it was proposed that the KORs may help trichomonads to survive in the presence of metronidazole. The KORs were identified using activity staining on native gels (Brown DM, Upcroft JA, Dodd HN, et al. Alternative 2-keto acid oxidoreductase activities in T. vaginalis. Mol Biochem Parasitol 1999;98:203-14). In the current study, we showed that the apparent KOR activity was caused by the non-enzymatic reduction of the indicator dye, nitroblue tetrazolium, by indolepyruvate, which is facilitated by Triton X-100 used to prepare the membrane fractions. We could not confirm the presence of KORs in metronidazole-resistant T. vaginalis. The low level indolepyruvate-dependent activity that is present in T. vaginalis strains sensitive to metronidazole is catalyzed by PFO, which was verified using the pure enzyme. Therefore, our results suggest that alternative 2-keto acid oxidoreductases do not exist in T. vaginalis.
- MeSH
- artefakty MeSH
- barvení a značení metody MeSH
- histocytochemie metody MeSH
- indoly metabolismus MeSH
- ketokyseliny metabolismus MeSH
- oktoxynol metabolismus MeSH
- oxidoreduktasy analýza MeSH
- tetrazoliová modř metabolismus MeSH
- Trichomonas vaginalis enzymologie MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
The main components responsible for the mechanical behavior of the arterial wall are collagen, elastin, and smooth muscle cells (SMCs) in the medial layer. We determined the structural and mechanical changes in porcine carotid arteries after administration of Triton® X-100, elastase, and collagenase using the inflation-deflation test. The arteries were intraluminarly pressurized from 0 to 200 mmHg, and the outer diameter of the artery was measured. The pressure-strain elastic modulus was determined based on the pressure/diameter ratio. The intima-media thickness, wall thickness, thickness of the tunica adventitia layer, and the area fractions of SMCs, elastin, and collagen within the arterial wall (A(A)(SMC/elastin/collagen, wall)) were measured using stereological methods. The relative changes in the relevant components of the treated samples were as follows: the decrease in A(A)(SMC, wall) after administration of Triton® X-100 was 11% ± 7%, the decrease in A(A)(elastin, wall) after administration of elastase was 40% ± 22%, and the decrease in A(A)(collagen, wall) after the application of collagenase was 51% ± 22%. The Triton® X-100 treatment led to a decrease in the SMC content that was associated with enlargement of the arterial wall (outer diameter) for pressures up to 120 mmHg, and with mechanical stiffening of the arterial wall at higher pressures. Elastase led to a decrease in the elastin content that was associated with enlargement of the arterial wall, but not with stiffening or softening. Collagenase led to a decrease in collagen content that was associated with a change in the stiffness of the arterial wall, although the exact contribution of mechanical loading and the duration of treatment (enlargement) could not be quantified.
- MeSH
- adventicie anatomie a histologie účinky léků MeSH
- arteriae carotides anatomie a histologie účinky léků fyziologie MeSH
- biomechanika fyziologie MeSH
- elastin metabolismus MeSH
- intimomediální šíře tepenné stěny MeSH
- kolagen metabolismus MeSH
- kolagenasy metabolismus MeSH
- modul pružnosti účinky léků MeSH
- oktoxynol aplikace a dávkování farmakologie MeSH
- Sus scrofa fyziologie MeSH
- svaly hladké cévní účinky léků fyziologie MeSH
- techniky in vitro MeSH
- tlak MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Removal of nonionic surfactants from municipal wastewater using a constructed wetland with a horizontal subsurface flow was studied in 2009 and 2010. Extraction spectrophotometry with 3',3″,5',5″-tetrabromophenolphthalein ethyl ester and KCl served to determine the analyte concentrations. Triton(®) X-100 was used as a standard to express the nonionic-surfactant concentrations. Anionic and cationic surfactants were shown not to interfere during the determination. Nonionic surfactants were degraded (to products undeterminable by the method) with a high average efficiency that reached 98.1% in 2009 and 99.1% in 2010, respectively. The average concentration of nonionic surfactants at the inflow was 0.978 mg/l, while it was close to the limit of quantification at the outflow (0.014 mg/l). A significant fraction of nonionic surfactants (38.7%) was already degraded during the pretreatment, and only 14.0% of the nonionic surfactants remained in the interstitial H(2) O taken in the vegetation bed at a distance of 1 m from the inflow zone at a 50-cm depth. Nonionic surfactants were degraded both under aerobic and anaerobic conditions.
The effect of non-ionic detergents on baclofen (GABAB-R agonist)-stimulated G-protein activity was measured as a [(35)S]GTPgammaS binding assay in the plasma membranes (PM) isolated from the brain tissue. The effect was clearly biphasic--a decrease in the activity was followed by an activation maximum and finally, at high concentrations, drastic inhibition of the G-protein activity was noticed. Contrarily, specific radioligand binding to GABAB-receptor was inhibited in the whole range of detergent concentrations step by step, i.e. it was strictly monophasic. The magnitude of both detergent effects was decreased in the same order of potency: Brij58>Triton X-100>Digitonin. The identical order was found when comparing detergents ability to alter fluorescence anisotropy of the membrane probe 1,6-diphenyl-1,3,5-hexatriene (rDPH) incorporated into the hydrophobic PM interior. Decrease of rDPH, in the order of Brij58>Triton X-100>Digitonin, was reflected as decrease of the S-order parameter and rotation correlation time phi paralleled by an increase of diffusion wobbling constant Dw (analysis by time-resolved fluorescence according to "wobble-in-cone" model). The influence of the detergents on the membrane organization at the polar headgroup region was characterized by Laurdan generalized polarization (GP). As before, the effect of detergents on GP parameters proceeded in the order: Brij58>Triton X-100>Digitonin.
- MeSH
- 2-naftylamin analogy a deriváty MeSH
- buněčná membrána metabolismus účinky léků MeSH
- cetomakrogol farmakologie MeSH
- difenylhexatrien MeSH
- difuze MeSH
- financování organizované MeSH
- fluorescenční barviva MeSH
- fluorescenční spektrometrie MeSH
- krysa rodu rattus MeSH
- laurany MeSH
- mozek metabolismus účinky léků MeSH
- oktoxynol farmakologie MeSH
- proteiny vázající GTP metabolismus MeSH
- receptory GABA-B metabolismus MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- zvířata MeSH
