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51.
52.
The enzymes involved in the protection of plant metabolism in presence of azo dye was characterized by studying activities of the role of antioxidant enzymes in the hairy roots (HRs) of Physalis minima L. during degradation of an azo dye, Reactive Black 8 (RB8). When the HRs were exposed to RB8 (30 mg L?1), a nine fold increase in SOD activity was observed after 24 h, while 22 and 50 fold increase in activity was observed for POX and APX respectively after 72 h, whereas there was no significant change in activity of CAT. The activation of different antioxidant enzymes at different time intervals under dye stress suggests the synchronized functioning of antioxidant machinery to protect the HRs from oxidative damage. FTIR analysis confirmed the degradation of dye and the non-toxic nature of metabolites formed after dye degradation was confirmed by phytotoxicity study. 相似文献
53.
Effect of Sodium-Glucose Cotransport Inhibition on Polycystic Kidney Disease Progression in PCK Rats
Sarika Kapoor Daniel Rodriguez Meliana Riwanto Ilka Edenhofer Stephan Segerer Katharyn Mitchell Rudolf P. Wüthrich 《PloS one》2015,10(4)
The sodium-glucose-cotransporter-2 (SGLT2) inhibitor dapagliflozin (DAPA) induces glucosuria and osmotic diuresis via inhibition of renal glucose reabsorption. Since increased diuresis retards the progression of polycystic kidney disease (PKD), we investigated the effect of DAPA in the PCK rat model of PKD. DAPA (10 mg/kg/d) or vehicle was administered by gavage to 6 week old male PCK rats (n=9 per group). Renal function, albuminuria, kidney weight and cyst volume were assessed after 6 weeks of treatment. Treatment with DAPA markedly increased glucose excretion (23.6 ± 4.3 vs 0.3 ± 0.1 mmol/d) and urine output (57.3 ± 6.8 vs 19.3 ± 0.8 ml/d). DAPA-treated PCK rats had higher clearances for creatinine (3.1 ± 0.1 vs 2.6 ± 0.2 ml/min) and BUN (1.7 ± 0.1 vs 1.2 ± 0.1 ml/min) after 3 weeks, and developed a 4-fold increase in albuminuria. Ultrasound imaging and histological analysis revealed a higher cyst volume and a 23% higher total kidney weight after 6 weeks of DAPA treatment. At week 6 the renal cAMP content was similar between DAPA and vehicle, and staining for Ki67 did not reveal an increase in cell proliferation. In conclusion, the inhibition of glucose reabsorption with the SGLT2-specific inhibitor DAPA caused osmotic diuresis, hyperfiltration, albuminuria and an increase in cyst volume in PCK rats. The mechanisms which link glucosuria to hyperfiltration, albuminuria and enhanced cyst volume in PCK rats remain to be elucidated. 相似文献
54.
Roland Benz Michael D. Jones Farhan Younas Elke Maier Niraj Modi Reinhard Mentele Friedrich Lottspeich Ulrich Kleinekath?fer John Smit 《PloS one》2015,10(11)
Caulobacter crescentus is an oligotrophic bacterium that lives in dilute organic environments such as soil and freshwater. This bacterium represents an interesting model for cellular differentiation and regulation because daughter cells after division have different forms: one is motile while the other is non-motile and can adhere to surfaces. Interestingly, the known genome of C. crescentus does not contain genes predicted to code for outer membrane porins of the OmpF/C general diffusion type present in enteric bacteria or those coding for specific porins selective for classes of substrates. Instead, genes coding for 67 TonB-dependent outer membrane receptors have been identified, suggesting that active transport of specific nutrients may be the norm. Here, we report that high channel-forming activity was observed with crude outer membrane extracts of C. crescentus in lipid bilayer experiments, indicating that the outer membrane of C. crescentus contained an ion-permeable channel with a single-channel conductance of about 120 pS in 1M KCl. The channel-forming protein with an apparent molecular mass of about 20 kDa was purified to homogeneity. Partial protein sequencing of the protein indicated it was a member of the OmpW family of outer membrane proteins from Gram-negative bacteria. This channel was not observed in reconstitution experiments with crude outer membrane extracts of an OmpW deficient C. crescentus mutant. Biophysical analysis of the C. crescentus OmpW suggested that it has features that are special for general diffusion porins of Gram-negative outer membranes because it was not a wide aqueous channel. Furthermore, OmpW of C. crescentus seems to be different to known OmpW porins and has a preference for ions, in particular cations. A putative model for OmpW of C. crescentus was built on the basis of the known 3D-structures of OmpW of Escherichia coli and OprG of Pseudomonas aeruginosa using homology modeling. A comparison of the two known structures with the model of OmpW of C. crescentus suggested that it has a more hydrophilic interior and possibly a larger diameter. 相似文献
55.
Jennifer L. Jones Sarika Saraswati Ashley S. Block Cheryl F. Lichti Maha Mahadevan Alan B. Diekman 《Glycoconjugate journal》2010,27(2):227-236
Galectin-3 is a β-galactoside-binding protein involved in immunomodulation, cell interactions, cancer progression, and pathogenesis
of infectious organisms. We report the identification and characterization of galectin-3 in human semen. In the male reproductive
tract, the ~30 kDa galectin-3 protein was identified in testis, epididymis, vas deferens, prostate, seminal vesicle, and sperm
protein extracts. In seminal plasma, galectin-3 was identified in the soluble fraction and in prostasomes, cholesterol-rich,
membranous vesicles that are secreted by the prostate and incorporated into seminal plasma during ejaculation. Two-dimensional
immunoblot analysis of purified prostasomes identified five galectin-3 isoelectric variants with a pI range of 7.0 to 9.2.
Affinity purification and tandem mass spectrometry of β-galactoside-binding proteins from prostasomes confirmed the presence
of galectin-3 in prostasomes and identified a truncated galectin-3 variant. The intact galectin-3 molecule contains a carbohydrate
recognition domain and a non-lectin domain that interacts with protein and lipid moieties. The identification of a monovalent
galectin-3 fragment with conserved carbohydrate-binding activity indicates the functional relevance of this truncation and
suggests a regulatory mechanism for galectin-3 in prostasomes. Surface biotinylation studies suggested that galectin-3 and
the truncated galectin-3 variant are localized to the prostasome surface. Prostasomes are proposed to function in immunosuppression
and regulation of sperm function in the female reproductive tract, are implicated in facilitating sexually-transmitted infections,
and are indicated in prostate cancer progression. Given the overlap in functional significance, the identification of galectin-3
in prostasomes lays the groundwork for future studies of galectin-3 and prostasomes in reproduction, disease transmission,
and cancer progression. 相似文献
56.
Background
Subcutaneous zygomycosis is a chronic infection caused by fungus of the order Entomophthorales. It can have varying presentations and presents in the nose and face area with gradually progressing subcutaneous swelling that may be difficult to diagnose unless a strong suspicion of fungal involvement is maintained. We present a case of subcutaneous zygomycosis in a 35-year-old male patient, resident of a North Indian state. The patient was diagnosed to be suffering from subcutaneous zygomycosis, the causative agent being Basidiobolus ranarum identified on culture and lactophenol cotton blue mount preparation. He responded well to treatment with Itraconazole and Terbinafine and is asymptomatic on follow-up. 相似文献57.
Polysaccharides excreted by cowpea Rhizobium strains JLn(c) and RA-1 were mixtures of complex acidic exopolysaccharides and low molecular weight neutral glucans. These polymers were fractionated using gel filtration chromatography. Purified fractions of the acidic heteropolymer reacted with peanut agglutinin to give precipitin bands when subjected to Ouchterlony gel diffusion. The acidic exopolysaccharide was found to contain mainly glucose, galactose, glucuronic acid, mannose and fucose. The non-carbohydrate substituents of the acidic heteropolymer were pyruvate, acetate and uronate which were identified by infrared and proton nuclear magnetic resonance spectroscopy as well as by chemical analysis.Abbreviations EPS
Extracellular polysaccharide
- YEM
yeast extract mannitol
- PNA
peanut agglutination
-
1H-NMR
proton nuclear magnetic resonance 相似文献
58.
59.
Fructose-1,6-diphosphatase (FDPase) from unripe mango was separated into two components by ammonium sulfate fractionation, one active at pH 6 (acidic FDPase) and the other at pH 8.5 (alkaline FDPase). The alkaline component had a lower Km. (0.15 × 10?3 M) than the acidic component (1.7 × 10?3 M) towards the substrate (FDP) and the allosteric inhibitor AMP. It also showed greater heat stability and higher activation in the presence of EDTA as compared to the acidic FDPase. Both components showed a higher activation with Mn2+ ions than with Mg2+ ions. 相似文献
60.
Propan-2-ol was used as an acyl acceptor for immobilized lipase-catalyzed preparation of biodiesel. The optimum conditions
for transesterification of crude jatropha (Jatropha curcas), karanj (Pongamia pinnata) and sunflower (Helianthus annuus) oils were 10% Novozym-435 (immobilized Candida antarctica lipase B) based on oil weight, alcohol to oil molar ratio of 4:1 at 50 °C for 8 h. The maximum conversions achieved using
propan-2-ol were 92.8, 91.7 and 93.4% from crude jatropha, karanj and sunflower oils, respectively. Reusability of the lipase
was maintained over 12 repeated cycles with propan-2-ol while it reached to zero by 7th cycle when methanol was used as an acyl acceptor, under standard reaction conditions.
Revisions requested 22 December 2005; Revisions received 26 January 2006 相似文献