Effects Of Detergents Research Articles

Effect of detergent binding on cytochrome P450 2B4 structure as analyzed by X-ray crystallography and deuterium-exchange mass spectrometry

Multiple crystal structures of CYP2B4 have demonstrated the binding of the detergent 5-cyclohexyl-1-pentyl-β-D-maltoside (CYMAL-5) in a peripheral pocket located adjacent to the active site. To explore the consequences of detergent binding, X-ray crystal structures of the peripheral pocket mutant CYP2B4 F202W were solved in the presence of hexaethylene glycol monooctyl ether (C8E6) and CYMAL-5. The structure in the presence of CYMAL-5 illustrated a closed conformation indistinguishable from the previously solved wild-type. In contrast, the F202W structure in the presence of C8E6 revealed a detergent molecule that coordinated the heme-iron and extended to the protein surface through the substrate access channel 2f. Despite the overall structural similarity of these detergent complexes, remarkable differences were observed in the A, A′, and H helices, the F-G cassette, the C-D and β4 loop region. Hydrogen-deuterium exchange mass spectrometry (DXMS) was employed to probe these differences and to test the effect of detergents in solution. The presence of either detergent increased the H/D exchange rate across the plastic regions, and the results obtained by DXMS in solution were consistent in general with the relevant structural snapshots. The study provides insight into effect of detergent binding and the interpretation of associated conformational dynamics of CYP2B4.

Effects observation of biomembrane detergent for laparoscopy instruments in Operating Room

Objective To explore the cleaning effects of biomembrane detergent on laparoscopy instruments in order to thoroughly clean the laparoscopy instruments in Operating Room, improve the quality of detergent of surgical instruments and prevent hospital infection. Methods A total of 400 polluted laparoscopy instruments in operating room were randomly divided into experimental group (200 instruments, biomembrane detergent) and control group (200 instruments, multi-enzyme detergent) according to tossing a coin. The cleaning effect were compared between two groups after finishing cleaning. Results The percent of pass of cleaning laparoscopy instruments with biomembrane detergent was 98.5% in experimental group which was better than that (80.5%) in control group with a significant difference between two groups (P<0.05). Conclusions Cleaning laparoscopy instruments with biomembrane detergent can improve the cleaning effect and ensure the quality of detergent of surgical instruments. Key words: Operating Room; Laparoscopy instruments; Cleaning; Biomembrane detergent

Elastic Deformation and Collective Dynamics in Lipid Membranes: A Solid-State 2H NMR Relaxation Study

Biomembrane functioning is significantly influenced by the composition and structure of the liquid-crystalline lipid bilayer [1]. Solid-state 2H NMR spectroscopy provides information about atomistic interactions among the membrane constituents by simultaneously probing structure and dynamics [2]. Here we examine the effect of water, osmolytes, cholesterol, and detergents on the liquid-crystalline properties of lipid membranes using NMR relaxation methods. We performed 2H NMR longitudinal (R1Z) and transverse quadrupolar-echo decay (R2QE) experiments on DMPC-d54 bilayers to study membrane lipid dynamics over the time scale ranging from nanoseconds to milliseconds. Plots of R1Z rates or transverse relaxation rates versus squared segmental order parameters (SCD2) show the emergence of collective lipid dynamics [3]. Such a functional behavior characterizes 3-D order-director fluctuations, due to the onset of membrane elasticity [3]. Yet at high hydration, a further R2QE enhancement and confinement of the functional square-law to the segments deeper in the bilayer is seen. Additional contributions from slower dynamics involving water-mediated membrane deformation are evident over mesoscopic length scales on the order of bilayer thickness. Such structural deformations are also evident from bilayer structural parameters calculated using a statistical mean-torque model [4]. The slow dynamics at high hydration or correspondingly low cholesterol or osmolyte concentration are due to modulation of elastic properties of the lipid bilayer. Analysis of the frequency dispersion of the transverse relaxation as a function of such external parameters reveals viscoelastic properties of the liquid-crystalline membranes. Such studies give insights into lipid rafts and membrane composition relevant for biomembrane function. [1] A. Leftin et al. (2014) Biophys. J. 107, 2274[2] K.J. Mallikarjuniah et al. (2011) Biophys. J.100, 98. [3] A. Leftin et al. (2014) eMagRes 4, 199. [4] J.J. Kinnun et al. (2015) BBA 1848, 246.

Biocatalytic synthesis of 3,4,5,3',5'-pentahydroxy-trans-stilbene from piceatannol by two-component flavin-dependent monooxygenase HpaBC.

HpaBC monooxygenase was previously reported to hydroxylate resveratrol to piceatannol. In this article, we report a novel catalytic activity of HpaBC for the synthesis of a pentahydroxylated stilbene. When Escherichia coli cells expressing HpaBC were incubated with resveratrol, the resulting piceatannol was further converted to a new product. This product was identified by mass spectrometry and NMR spectroscopy as a 5-hydroxylated piceatannol, 3,4,5,3',5'-pentahydroxy-trans-stilbene (PHS), which is a reportedly valuable biologically active stilbene derivative. We attempted to produce PHS from piceatannol on a flask scale. After examining the effects of detergents and buffers on PHS production, E. coli cells expressing HpaBC efficiently hydroxylated piceatannol to PHS in a reaction mixture containing 1.5% (v/v) Tween 80 and 100 mM 3-morpholinopropanesulfonic acid-NaOH buffer at pH 7.5. Under the optimized conditions, the whole cells regioselectively hydroxylated piceatannol, and the production of PHS reached 6.9 mM (1.8 g L(-1)) in 48 h.

Detergent decellularization methods affect the surface molecular functionality of biologic scaffolds

Detergent decellularization methods affect the surface molecular functionality of biologic scaffolds

Changes in Liver Ganglioside Metabolism in Obstructive Cholestasis – the Role of Oxidative Stress

Bile acids have been implicated in cholestatic liver damage, primarily due to their detergent effect on membranes and induction of oxidative stress. Gangliosides can counteract these harmful effects by increasing the rigidity of the cytoplasmic membrane. Induction of haem oxygenase (HMOX) has been shown to protect the liver from increased oxidative stress. The aim of this study was to determine the changes in the synthesis and distribution of liver gangliosides following bile duct ligation (BDL), and to assess the effects of HMOX both on cholestatic liver injury and ganglioside metabolism. Compared to controls, BDL resulted in a significant increase in total as well as complex gangliosides and mRNA expression of corresponding glycosyltransferases ST3GalV, ST8SiaI and B3GalTIV. A marked shift of GM1 ganglioside from the intracellular compartment to the cytoplasmic membrane was observed following BDL. Induction of oxidative stress by HMOX inhibition resulted in a further increase of these changes, while HMOX induction prevented this effect. Compared to BDL alone, HMOX inhibition in combination with BDL significantly increased the amount of bile infarcts, while HMOX activation decreased ductular proliferation. We have demonstrated that cholestasis is accompanied by significant changes in the distribution and synthesis of liver gangliosides. HMOX induction results in attenuation of the cholestatic pattern of liver gangliosides, while HMOX inhibition leads to the opposite effect.

The Toxicity Effect of Detergent on Enzymatic and Protein Activities of African Mud Catfish (Clarias gariepinus)

The toxicities of commercial detergent (Ariel; Linear Alkylbenzene Sulfonate), a household cleaning agent was investigated on some enzymatic and protein activities of juvenile African mud catfish (Clarias gariepinus). Fishes were exposed to lethal and sub-lethal concentrations of detergent for 21 days in a renewal bioassay procedure. The median lethal concentrations (LC50) were derived using Finney probit method while protein and enzymatic activities were determined using Biuret and Randox methods respectively. The LC50 values for 96 hours acute bioassay test was 0.11 g/l. Detergent exposed fish showed significant increase (p ≤ 0.05) in serum AST (109.00 ± 3.79 to 111.00 ± 3.80); liver globulin at 0.008 g/l (2.47 ± 0.03) and 0.013 g/l (2.57 ± 0.03). Significant decrease was recorded in liver AST, (ALP and creatinine 137 ± 4.67 to 151 ± 2.52; 80.67 ± 0.88 to 86.67 ± 3.67 and 0.27 ± 0.07 to 0.60 ± 0.00 respectively across all sub- lethal concentrations. The enzymes and proteins from serum, liver and heart tissues of fish have shown vividly that detergent is capable of inducing adverse effects and impacting on the health of fish. Therefore, the presence of detergent in aquatic ecosystem could be dangerous to fish and subsequently human health.

A green alternative for oily wastewater treatment: lipase from Acinetobacter haemolyticus NS02-30

Biological treatment of wastewater is negatively affected by high concentrations of oil and grease, which decrease the oxygen transfer rate in the aerobic process by forming a layer on the water surface, making removal of oil and grease from manufacturing wastewater essential. However, the most common currently used techniques are inadequate as well as costly, and chemical methods create environmental pollution. By contrast, fermentation can be used to produce extracellular microbial lipases relatively cheaply and in large quantities for industrial use. Biological methods that use lipase enzymes also represent an appropriate, “green” choice for removing oil and grease from wastewater. This study identified and characterized a novel lipase produced from bacteria isolated by screening soil and olive pomace samples for lipolytic activity. The bacteria was subsequently identified as Acinetobacter haemolyticus, and the lipase produced from this bacteria (LipAH02–30) was then purified and characterized. Findings are presented as means ± SD. Enzyme Km and Vmax were 0.8mM and 3.833 mmol/ml/min, respectively. Optimal temperature and pH for enzyme activity were identified as 40°C and 9.0, with good stability exhibited at temperatures ranging between 10 and 30°C and a pH range of 5.0–11.0. The effects of organic solvents, metal ions, surfactants, commercial detergents, enzyme inhibitors, oxidizing agents, protease and boric acid on LipAH02–30 activity were also examined. The enzyme was found to be highly stable at +4°C, displaying 90% activity even after 60 d, and to be effective in hydrolyzing oils found in kitchen wastewater. The high stability demonstrated by LipAH02–30 over a wide range of temperatures and pHs, along with its ability to maintain its activity in the presence of various surfactants, oxidizing agents, proteases and commercial detergents, indicates it to be an effective solution for the treatment of lipid-rich wastewater.

Thermal proteome profiling monitors ligand interactions with cellular membrane proteins.

We extended thermal proteome profiling to detect transmembrane protein-small molecule interactions in cultured human cells. When we assessed the effects of detergents on ATP-binding profiles, we observed shifts in denaturation temperature for ATP-binding transmembrane proteins. We also observed cellular thermal shifts in pervanadate-induced T cell-receptor signaling, delineating the membrane target CD45 and components of the downstream pathway, and with drugs affecting the transmembrane transporters ATP1A1 and MDR1.

Effect of Detergents on Galactoside Binding by Melibiose Permeases.

The effect of various detergents on the stability and function of the melibiose permeases of Escherichia coli (MelBEc) and Salmonella typhimurium (MelBSt) was studied. In n-dodecyl-β-d-maltoside (DDM) or n-undecyl-β-d-maltoside (UDM), WT MelBSt binds melibiose with an affinity similar to that in the membrane. However, with WT MelBEc or MelBSt mutants (Arg141 → Cys, Arg295 → Cys, or Arg363 → Cys), galactoside binding is not detected in these detergents, but binding to the phosphotransferase protein IIA(Glc) is maintained. In the amphiphiles lauryl maltose neopentyl glycol (MNG-3) or glyco-diosgenin (GDN), galactoside binding with all of the MelB proteins is observed, with slightly reduced affinities. MelBSt is more thermostable than MelBEc, and the thermostability of either MelB is largely increased in MNG-3 or GDN. Therefore, the functional defect with DDM or UDM likely results from the relative instability of the sensitive MelB proteins, and stability, as well as galactoside binding, is retained in MNG-3 or GDN. Furthermore, isothermal titration calorimetry of melibiose binding with MelBSt shows that the favorable entropic contribution to the binding free energy is decreased in MNG-3, indicating that the conformational dynamics of MelB is restricted in this detergent.

High Efficacy but Low Potency of δ-Opioid Receptor-G Protein Coupling in Brij-58-Treated, Low-Density Plasma Membrane Fragments.

Principal FindingsHEK293 cells stably expressing PTX-insensitive δ-opioid receptor-Gi1α (C351I) fusion protein were homogenized, treated with low concentrations of non-ionic detergent Brij-58 at 0°C and fractionated by flotation in sucrose density gradient. In optimum range of detergent concentrations (0.025–0.05% w/v), Brij-58-treated, low-density membranes exhibited 2-3-fold higher efficacy of DADLE-stimulated, high-affinity [32P]GTPase and [35S]GTPγS binding than membranes of the same density prepared in the absence of detergent. The potency of agonist DADLE response was significantly decreased. At high detergent concentrations (>0.1%), the functional coupling between δ-opioid receptors and G proteins was completely diminished. The same detergent effects were measured in plasma membranes isolated from PTX-treated cells. Therefore, the effect of Brij-58 on δ-opioid receptor-G protein coupling was not restricted to the covalently bound Gi1α within δ-opioid receptor-Gi1α fusion protein, but it was also valid for PTX-sensitive G proteins of Gi/Go family endogenously expressed in HEK293 cells. Characterization of the direct effect of Brij-58 on the hydrophobic interior of isolated plasma membranes by steady-state anisotropy of diphenylhexatriene (DPH) fluorescence indicated a marked increase of membrane fluidity. The time-resolved analysis of decay of DPH fluorescence by the “wobble in cone” model of DPH motion in the membrane indicated that the exposure to the increasing concentrations of Brij-58 led to a decreased order and higher motional freedom of the dye.SummaryLimited perturbation of plasma membrane integrity by low concentrations of non-ionic detergent Brij-58 results in alteration of δ-OR-G protein coupling. Maximum G protein-response to agonist stimulation (efficacy) is increased; affinity of response (potency) is decreased. The total degradation plasma membrane structure at high detergent concentrations results in diminution of functional coupling between δ-opioid receptors and G proteins.

Ecotoxicological consideration of some industrial chemicals on three biological sentinels

Ecotoxicological effects of industrial detergent (Neatex) and corrosion inhibitor (Norust CR 486) commonly released into the Nigerian environment were studied using laboratory toxicity test. These industrial chemicals are used copiously in the environment as if they do not have any ecotoxicological effects. Fish, shrimp and earthworms were exposed to varying concentrations of the test chemicals using the Organisation for Economic Cooperation and Development (OECD) # 203, 218 and 207 protocols respectively. The methods were employed because they give consistent and reproducible data. The water, sediment and soil ratings indicate that both chemicals were toxic to the organisms and the estimated 4, 10 and 14 days lethal concentration (LC50) showed that the corrosion inhibitor was more toxic than the industrial detergent. In the earthworm bioassay, the estimated LC50 showed that Norust CR 486 (207.61 ± 14.09 mg/kg) was more toxic than Neatex (413.82 ± 0 mg/kg). In the fish bioassay, results showed that death cause to older species may lead to elimination of potentially reproductive organisms. The muscle glycogen levels of fish exposed to the test chemicals significantly decreased when compared with the levels measured in the control group. Depletion in the muscle glycogen level reported was 67% (Neatex) and 75% (Norust CR 486) at the end of the 28-day experiment. Similarly, there was significant difference in surfactant bioaccumulation in fish (gills, gut and muscle tissue) for the test chemicals at levels of (p &lt; 0.05). The observed sensitivity of the test organisms to both chemicals indicate that appropriate safety measures such as adherence to standard operating procedures should be applied before use and disposal of surfactant-containing chemicals since the test chemicals were toxic in the three media. This would ensure that the biotic components of the Nigerian Niger Delta ecosystem are prudently protected.Keywords: Toxicity, fish, shrimp, earthworm, surfactant, muscle glycogen.

집 먼지 진드기에 대한 유칼립투스 세제의 기피효과

The exposure to house dust mites is closely connected with allergic diseases such as atopic dermatitis, allergic rhinitis and asthma. Control of house dust mite populations has been principally achieved by using chemical insecticides. But the risk to human health would be a potential problem. Moreover, house dust mite remain as allergens even after death. Therefore, repelling the house dust mites is more effective method than killing them. The use of plant-derived repellents has been considered as a promising alternative to chemical repellents. Eucalyptus oils are regarded as safe compounds, there have been attempts to commercialize and market the insecticides/repellent products containing Eucalyptus oil as such or based upon them. For that reason, we experimented repellent activity against these mites using laundry detergent with Eucalyptus oil in this experiment. House dust mites (Dermatophagoides farinae and Dermatophagoides pteronyssinus) were exposed at different concentrations (4, 8, 16, 32 L/mL) in fabric treated laundry detergent with Eucalyptus oil for 24 hours. The repellent effects (%) of laundry detergent with Eucalyptus oil exposed at 4, 8, 16, and 32 L/mL were 48.16%, 74.62%, 52.67%, and 44.47%, respectively. These results suggest that laundry detergent with Eucalyptus oil have potential effect to repel the house dust mites.

Effect of Detergent on the Quantification of Grapevine Downy Mildew Sporangia from Leaf Discs

Grapevine downy mildew (DM), caused by the oomycete Plasmopara viticola (Berk. &amp; Curt.) Berlese &amp; de Toni, is a major disease, especially in humid viticultural areas. Development of resistant cultivars is an important objective for grapevine breeding. To establish a reliable and inexpensive quantitative method to aid in breeding for DM resistance, we improved the method for counting the number of sporangia on leaf discs, and developed a method for counting the number of sporangia in solution. To prevent the loss of DM sporangia from adhesion onto plastic ware, we found as little as 0.01% Tween 20 was effective. On the other hand, this detergent was shown to have a severe inhibitory effect upon DM infection of leaves. We developed a sporangia counting method using dried droplets of DM suspensions, and the method was highly correlated with counting by hemacytometer (R2 &gt; 0.96). The nonparametric Spearman’s rank correlations between visual rating and the number of the sporangia were as high as ρ = 0.82 to 0.91, suggesting that evaluation by the visual rating could provide a good estimate of the sporangia numbers on leaf discs. We established a high-throughput and inexpensive method with acceptable accuracy for DM resistance evaluation based on a leaf disc assay, and our results suggested that visual ratings of infected leaf discs provide a good estimate of sporangia numbers.

The Effect of Detergent, Temperature, and Lipid on the Oligomeric State of MscL Constructs: Insights from Mass Spectrometry

The mechanosensitive channel of large conductance (MscL) acts as an emergency release valve for osmotic shock of bacteria preventing cell lysis. The large pore size, essential for function, requires the formation of oligomers with tetramers, pentamers, or hexamers observed depending on the species and experimental approach. We applied non-denaturing (native) mass spectrometry to five different homologs of MscL to determine the oligomeric state under more than 50 different experimental conditions elucidating lipid binding and subunit stoichiometry. We found equilibrium between pentameric and tetrameric species, which can be altered by detergent, disrupted by binding specific lipids, and perturbed by increasing temperature (37°C). We also established the presence of lipopolysaccharide bound to MscL and other membrane proteins expressed in Escherichia coli, revealing a potential source of heterogeneity. More generally, we highlight the use of mass spectrometry in probing membrane proteins under a variety of detergent-lipid environments relevant to structural biology.

Washing oiled marine birds in New Zealand—do we have a detergent that can be used?

An efficacious oiled wildlife response requires quick action to remove external contamination of birds’ plumage in order to minimise ingestion of the oil and reinstitute waterproofing and thermoregulatory abilities, with the ultimate goals of increasing likelihood of release and maximising survival. The accessibility of the preferred detergent used in washing wildlife, Dawn® (Procter & Gamble), is limited for isolated nations such as New Zealand and its continuous availability in an extended oil spill response is a concern. This study investigates eight detergents manufactured in either New Zealand or Australia that are easily accessible, and compares their effectiveness at removing oil contaminants from feathers with Dawn®. Results indicate that none of the locally manufactured detergents was as effective as Dawn®. Availability and effectiveness of detergents for oil spill response are important for New Zealand's oil spill strategy and for rehabilitation of oil-affected marine birds throughout New Zealand.

Whole Cell Bioconversion of Ricinoleic Acid to 12-Ketooleic Acid by Recombinant Corynebacterium glutamicum-Based Biocatalyst.

The biocatalytic efficiency of recombinant Corynebacterium glutamicum ATCC 13032 expressing the secondary alcohol dehydrogenase of Micrococcus luteus NCTC2665 was studied. Recombinant C. glutamicum converts ricinoleic acid to a product, identified by gas chromatography/mass spectrometry as 12-ketooleic acid (12-oxo-cis-9-octadecenoic acid). The effects of pH, reaction temperature, and non-ionic detergent on recombinant C. glutamiucm whole cell bioconversion were examined. The determined optimal conditions for production of 12-ketooleic acid are pH 8.0, 35°C, and 0.05 g/l Tween80. Under these conditions, recombinant C. glutamicum produces 3.3 mM 12-ketooleic acid, with a 72% (mol/mol) maximum conversion yield, and 1.1 g/l/h volumetric productivity in 2 h; and 3.9 mM 12- ketooleic acid, with a 74% (mol/mol) maximum conversion yield, and 0.69 g/l/h maximum volumetric productivity in 4 h of fermentation. This study constitutes the first report of significant production of 12-ketooleic acid using a recombinant Corynebacterium glutamicum-based biocatalyst.

Lipid Transfer Kinetics from Nanolipoprotein Particles to Bicelles

Nanolipoprotein particles (NLPs), also known as nanodiscs, are lipid bilayers bounded by apolipoprotein. We recently showed that lipids and membrane proteins cannot exchange between NLPs. However, addition of bicelles opens NLPs and transfers their contents to bicelles, which freely exchange lipids and proteins. Because monomeric membrane proteins can be prepared in NLPs by cell-free protein synthesis, the bicelle-induced transfer process may provide a new method for studying membrane protein oligomerization. The mechanism of the NLP-bicelle interaction is unknown. We have now tested the effects of bicelle detergent (DHPC), apolipoprotein (MSP1E3D1), and temperature on lipid transfer from NLPs to bicelles, using stopped-flow kinetics. NLPs were prepared with fluorescent lipids (0.02 to 0.05 mole fraction), consisting of FRET donors (NBD-PE) and acceptors (LR-PE) at approximately equal concentrations. NLPs were mixed with a 200-fold molar excess of DHPC/DMPC bicelles (equimolar 6- and 14-carbon acyl chains) in a stopped-flow fluorometer. The rate of lipid transfer was monitored by the appearance of unquenched NBD fluorescence at 520 nm. The observed pseudo-first-order rate constant was surprisingly small (0.26/sec). NLPs did not react with DHPC alone below its critical micelle concentration (cmc). Above the cmc, the reaction was complete within the instrument dead time. Thus, the rate-limiting step is not the reaction of NLPs with DHPC monomers or micelles. Added MSP1E3D1 had no effect on the rate, ruling out free apolipoprotein involvement. The NLP-bicelle mixing rate showed a strong temperature dependence (activation energy = 28 kcal/mol). Near or below the DMPC phase transition temperature, the kinetics were biphasic. The results suggest NLP-bicelle mixing kinetics may be mechanistically similar to lipid mixing via fusion pores.

Effect of non-ionic detergents on pH measurement using a test strip

Effect of non-ionic detergents on pH measurement using a test strip

Effect ofBacillus cereusHemolysin II on Hepatocyte Cells

We investigated the efficiency of increasing the permeability (permeabilization) of cell membranes in primary liver cells by Bacillus cereus hemolysin II. An assessment of the degree of permeabilization was car ried out by measuring the fluorescence intensity of various low molecular weight dyes, which enter through pores into hepatocyte cells cultivated with hemolysin. We uncovered a high efficacy of hemolysin HlyII action on hepatocyte cell walls, which exceeded the effect of nonionic detergent, digitonin, which is commonly employed for pore formation in various cell membranes. Our results also point to the reversibility of membrane permeabilization in primary hepatocytes. The data obtained in this study can be utilized for assessments of pore-forming activity, in studies of hepatic mechanisms of action, and also the determination of the liver toxicity for different low molecular weight drugs.