Sample records for detergents

  1. Detergent-compatible proteases: microbial production, properties, and stain removal analysis.

    PubMed

    Niyonzima, Francois Niyongabo; More, Sunil

    2015-01-01

    Proteases are one of the most important commercial enzymes used in various industrial domains such as detergent and leather industries. The alkaline proteases as well as other detergent-compatible enzymes such as lipases and amylases serve now as the key components in detergent formulations. They break down various stains during fabric washing. The search for detergent-compatible proteases with better properties is a continuous exercise. The current trend is to use detergent-compatible proteases that are stable over a wide temperature range. Although the proteases showing stability at elevated pH have the capacity to be used in detergent formulations, their usage can be significant if they are also stable and compatible with detergent and detergent ingredients, and also able to remove protein stains. Despite the existence of some reviews on alkaline proteases, there is no specification for the use of alkaline proteases as detergent additives. The present review describes the detergent-compatible proteases tested as detergent additives. An overview was provided for screening, optimization, purification, and properties of detergent compatible proteases, with an emphasis on the stability and compatibility of the alkaline proteases with the detergent and detergent compounds, as well as stain removal examination methods.

  2. Coproduction of detergent compatible bacterial enzymes and stain removal evaluation.

    PubMed

    Niyonzima, Francois N; More, Sunil S

    2015-10-01

    Most of the detergents that are presently produced contain the detergent compatible enzymes to improve and accelerate the washing performance by removing tough stains. The process is environment friendly as the use of enzymes in the detergent formulation reduces the utilization of toxic detergent constituents. The current trend is to use the detergent compatible enzymes that are active at low and ambient temperature in order to save energy and maintain fabric quality. As the detergent compatible bacterial enzymes are used together in the detergent formulation, it is important to co-produce the detergent enzymes in a single fermentation medium as the enzyme stability is assured, and production cost gets reduced enormously. The review reports on the production, purification, characterization and application of detergent compatible amylases, lipases, and proteases are available. However, there is no specific review or minireview on the concomitant production of detergent compatible amylases, lipases, and proteases. In this minireview, the coproduction of detergent compatible enzymes by bacterial species, enzyme stability towards detergents and detergent components, and stain release analysis were discussed. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Detergent-compatible bacterial amylases.

    PubMed

    Niyonzima, Francois N; More, Sunil S

    2014-10-01

    Proteases, lipases, amylases, and cellulases are enzymes used in detergent formulation to improve the detergency. The amylases are specifically supplemented to the detergent to digest starchy stains. Most of the solid and liquid detergents that are currently manufactured contain alkaline enzymes. The advantages of using alkaline enzymes in the detergent formulation are that they aid in removing tough stains and the process is environmentally friendly since they reduce the use of toxic detergent ingredients. Amylases active at low temperature are preferred as the energy consumption gets reduced, and the whole process becomes cost-effective. Most microbial alkaline amylases are used as detergent ingredients. Various reviews report on the production, purification, characterization, and application of amylases in different industry sectors, but there is no specific review on bacterial or fungal alkaline amylases or detergent-compatible amylases. In this mini-review, an overview on the production and property studies of the detergent bacterial amylases is given, and the stability and compatibility of the alkaline bacterial amylases in the presence of the detergents and the detergent components are highlighted.

  4. Availability of manufacturers' information on efficacy and compatibility of detergents used for cleaning dental instruments.

    PubMed

    Calvert, G; Murray, C A; Smith, A J; Hurrell, D

    2012-05-25

    To review physico-chemical data supplied for commercially available detergents marketed for manual and/or ultrasonic cleansing of reusable dental instruments. Manufacturers/suppliers of commercially available detergents for manual or ultrasonic cleaning of dental instruments within primary dental care were invited to supply product information. A structured questionnaire requested details on a range of physical and chemical properties for each detergent. Seventeen detergent manufacturers/suppliers, encompassing 31 commercially available detergents were identified. Ten of the 17 manufacturers provided information on 23 (74%) of the detergent formulations. Nine detergents were of neutral pH, ten mild alkalis (pH 7.5-10.5) and four strong alkalis (pH >10.5). Sixteen detergents were recommended for ultrasonic and manual cleaning, four stated ultrasonic use and three manual only. Ten detergents cited enzymatic activity as their main mode of action, but only six manufacturers provided detailed information. Four detergents recommended by manufacturers as suitable for manual washing had a strong alkaline pH (>10.5), presenting chemical hazards to users. Two strong alkaline detergents did not warn users of potential adverse effects of such alkaline solutions (corrosion) upon aluminium containing instruments. Only one detergent had investigated the potential toxicity of detergent residuals remaining on instruments after reprocessing. It has proven challenging to collate physico-chemical data on detergents suitable for use in manual and/or ultrasonic cleaning of dental instruments in general dental practice. Standardisation of information on the nature and efficacy of dental detergents in a readily accessible form would be beneficial to dental practice.

  5. Summary of: availability of manufacturers' information on efficacy and compatibility of detergents used for cleaning dental instruments.

    PubMed

    Barker, Chris

    2012-05-25

    To review physico-chemical data supplied for commercially available detergents marketed for manual and/or ultrasonic cleansing of reusable dental instruments. Manufacturers/suppliers of commercially available detergents for manual or ultrasonic cleaning of dental instruments within primary dental care were invited to supply product information. A structured questionnaire requested details on a range of physical and chemical properties for each detergent. Seventeen detergent manufacturers/suppliers, encompassing 31 commercially available detergents were identified. Ten of the 17 manufacturers provided information on 23 (74%) of the detergent formulations. Nine detergents were of neutral pH, ten mild alkalis (pH 7.5-10.5) and four strong alkalis (pH >10.5). Sixteen detergents were recommended for ultrasonic and manual cleaning, four stated ultrasonic use and three manual only. Ten detergents cited enzymatic activity as their main mode of action, but only six manufacturers provided detailed information. Four detergents recommended by manufacturers as suitable for manual washing had a strong alkaline pH (>10.5), presenting chemical hazards to users. Two strong alkaline detergents did not warn users of potential adverse effects of such alkaline solutions (corrosion) upon aluminium containing instruments. Only one detergent had investigated the potential toxicity of detergent residuals remaining on instruments after reprocessing. It has proven challenging to collate physico-chemical data on detergents suitable for use in manual and/or ultrasonic cleaning of dental instruments in general dental practice. Standardisation of information on the nature and efficacy of dental detergents in a readily accessible form would be beneficial to dental practice.

  6. Experimenting with Detergents

    ERIC Educational Resources Information Center

    Mitchell, Gail; Phillips, Donald B.

    1977-01-01

    Lists materials and procedures for experimenting with detergents. Included are methods for determination of the densities of dry detergents, ph values of detergent solutions, and a discussion of the ability of detergents to remove iodine stains from cloth. (CS)

  7. Movement and fate of detergents in groundwater: a field study

    USGS Publications Warehouse

    Thurman, E.M.; Barber, L.B.; LeBlanc, D.

    1986-01-01

    The major cations, anions, and detergents in a plume of contaminated groundwater at Otis Air Base on Cape Cod (Mass., U.S.A.) have moved approximately 3.5 km down gradient from the disposal beds. We hypothesize that the detergents form two distinct plumes, which consist of alkyl benzene sulfonates (ABS) detergents and linear alkyl sulfonates (LAS) and sodium dodecyl sulfate (NaLS) detergents. The ABS detergents were deposited from approximately 1940 through 1965, when ABS detergents were banned. From 1965 to the present, LAS and NaLS detergents were in the sewage. The ABS detergents appear to be transported in the aquifer at the same rate as the specific conductance (major cations and anions) and boron, which are currently used as conservative tracers of the plume of contaminated groundwater. There appears to be little or no biological degradation of the ABS detergents in the aquifer, based on their concentration in the plume. On the other hand, the LAS and NaLS detergents have degraded rapidly and have been detected only 0.6 km down gradient. The roleof the detergents in the transport of other organic compounds in the plume is nuclear. There is a separation of the ABS detergent plume and the volatile organic compound plume; however, the time of entry of the detergents and the volatile organic compounds is unknown. Therefore, it is not possible to conclude on the interaction of these two classes of compounds. ?? 1986.

  8. Effects of wastewater sludge and its detergents on the stability of rotavirus

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ward, R.L.; Ashley, C.S.

    1980-06-01

    Wastewater sludge reduced the heat required to inactivate rotavirus SA-11, and ionic detergents were identified as the sludge components responsible for this effect. A similar result was found previously with reovirus. The quantitative effects of individual ionic detergents on rotavirus and reovirus were very different, and rotavirus was found to be extremely sensitive to several of these detergents. However, neither virus was destabilized by nonionic detergents. On the contrary, rotavirus was stabilized by a nonionic detergent against the potent destabilizing effects of the ionic detergent sodium dodecyl sulfate. The destabilizing effects of both cationic and anionic detergents on rotavirus weremore » greatly altered by changes in the pH of the medium.« less

  9. The Effect of Detergents on the Morphology and Immunomodulatory Activity of Malassezia furfur.

    PubMed

    Kim, Su-Han; Ko, Hyun-Chang; Kim, Moon-Bum; Kwon, Kyung-Sool; Oh, Chang-Keun

    2009-05-01

    Several workers have found that Malassezia are capable of suppressing cytokine release and downregulating the phagocytic function of monocytes. But lipid-depleted Malassezia furfur (M. furfur) extracts have also been shown to induce increased production of TNF-alpha, IL-6 and IL-1beta in monocytes. We thought that the detergents in shampoos or soaps could change the composition of the lipid in the M. furfur cell wall. We studied whether detergents affect the morphology of M. furfur and if the inflammatory cytokine profiles change in the monocytes treated with detergent-treated M. furfur. Commonly used detergents such as sodium lauryl sulfate, ammonium lauryl sulfate and tween-80 were respectively added to the modified Leeming-Notman's media. M. furfur was cultivated in each media (detergent-added or untreated). Thereafter, the surface morphology of the yeast was evaluated by scanning and transmission electron microscopy. The cytokine profiles of monocytes, which were treated by M. furfur with or without detergents, were also evaluated. The detergent-treated M. furfur were similar to the lipid-extracted form of M. furfur on the electron microscopic study, with a recessed, withered surface and with thinner and rather electron transparent cell walls than the detergent-untreated M. furfur. The levels of TNF-alpha were higher in monocytes treated with detergent-treated Malassezia than that in the monocytes treated with the detergent-untreated Malassezia (p<0.05). According to the findings in this study, it could be inferred that the detergents in shampoos or soaps affect the lipid layers of the Malassezia cell wall and these lipid-extracted Malassezia induce or aggravate some inflammatory conditions. But to correlate the relationship between detergents and Malassezia-associated diseases, in vivo experiments that will focus on short-term contact with detergents in real life conditions should be done.

  10. Refractive index-based determination of detergent concentration and its application to the study of membrane proteins

    PubMed Central

    Strop, Pavel; Brunger, Axel T.

    2005-01-01

    The concentration of detergent in membrane protein preparations can have a critical role on protein stability, function, and the potential for crystallization. Unfortunately, dialysis or protein concentration can lead to an unknown amount of detergent in the final membrane protein preparations. Here we present a method for the determination of detergent concentration based on refractive index of the detergent solution. This method was applied to quantitate the amount of detergent remaining in solution after concentration in various concentrators. We found that the ability of the tested detergents to pass through the molecular weight cutoff membrane correlates well with detergent micelle size. Therefore, the micelle size can be used as a rough guide to estimate the retention of a given detergent in various molecular weight cutoff concentrators. The refractive index method is exceptionally informative when coupled with size exclusion chromatography and light scattering, and can be used to determine the oligomeric state of the membrane protein, the size of a protein-associated micelle, as well as the amount and size of the unbound detergent micelle. PMID:16046633

  11. Refractive index-based determination of detergent concentration and its application to the study of membrane proteins.

    PubMed

    Strop, Pavel; Brunger, Axel T

    2005-08-01

    The concentration of detergent in membrane protein preparations can have a critical role on protein stability, function, and the potential for crystallization. Unfortunately, dialysis or protein concentration can lead to an unknown amount of detergent in the final membrane protein preparations. Here we present a method for the determination of detergent concentration based on refractive index of the detergent solution. This method was applied to quantitate the amount of detergent remaining in solution after concentration in various concentrators. We found that the ability of the tested detergents to pass through the molecular weight cutoff membrane correlates well with detergent micelle size. Therefore, the micelle size can be used as a rough guide to estimate the retention of a given detergent in various molecular weight cutoff concentrators. The refractive index method is exceptionally informative when coupled with size exclusion chromatography and light scattering, and can be used to determine the oligomeric state of the membrane protein, the size of a protein-associated micelle, as well as the amount and size of the unbound detergent micelle.

  12. Affinity Chromatography in Nonionic Detergent Solutions

    NASA Astrophysics Data System (ADS)

    Robinson, Jack B.; Strottmann, James M.; Wick, Donald G.; Stellwagen, Earle

    1980-10-01

    Anionic dye affinity chromatography is commonly unproductive in the presence of nonionic detergents used to extract particulate proteins. Using lactate dehydrogenase as a model protein, Cibacron blue F3GA as a model dye, and Triton X-100 as a model detergent, we find that the dye is encapsulated in nonionic detergent micelles, rendering the dye incapable of ligation with the enzyme. However, the dye can be liberated from the micelles without altering the nonionic detergent concentration by addition of an anionic detergent, such as deoxycholate or sodium dodecyl sulfate, forming mixed anionic/nonionic micelles that displace the anionic dye. Encapsulation of the anionic detergents prevents their activity as protein denaturants. These observations have been successfully translated to the dye affinity chromatography of a detergent extract of brain particulate cyclic nucleotide phosphodiesterase.

  13. [Evaluation of the mutagenicity of detergents by tests on bacteria, plant cells and human leucocytes.].

    PubMed

    Feretti, Donatella; Pedrazzani, Roberta; Ceretti, Elisabetta; Zerbini, Ilaria; Gozio, Eleonora; Belotti, Caterina; Alias, Carlotta; Donato, Francesco; Gelatti, Umberto

    2009-01-01

    The aim of this study was to evaluate the mutagenicity of several traditional detergents and that of newer more biodegradable detergents, by using a bacterial test (Ames test), a plant cell test (Allium cepa micronuclei test) and a human leucocyte test (Comet test). All tests were conducted using a wide range of doses (1-2000 mg/l). None of the examined detergents induced mutations in S.typhimurium. One traditional detergent showed a genotoxic effect with the A. cepa test, while all newer detergents and one traditional detergent were shown by the Comet test to be capable of inducing DNA damage.

  14. Detergents compared with each other and with antiseptics as skin 'degerming' agents.

    PubMed Central

    Lilly, H. A.; Lowbury, E. J.; Wilkins, M. D.

    1979-01-01

    Three detergent preparations (bar soap, 'Hibiscrub' base and 'LIC 76'), TWO ANTISEPTic preparations (0.5% chlorhexidine in 95% ethyl alcohol and an alcohol jelly, 'Alcogel'), and one antiseptic-detergent solution (4% chlorhexidine gluconate in a detergent base, 'Hibiscrub') were compared for their effectiveness, on a single use, in reducing the yield of bacteria from the hands of volunteers. The antiseptic and antiseptic--detergent preparations were more effective than the detergents, with a mean reduction in yield of skin bacteria of 96.0% after use of alcoholic chlorhexidine and of 81.2% after use of Hibiscrub. One of the detergents, LIC 76, appeared more effective than the others, causing a mean reduction in the yield of skin bacteria of 41.5%, compared with reductions of 4.6% by the Hibiscrub detergent base and an increase of 3.2% with bar soap; unlike the other detergents, LIC 76 was found to have appreciable bacteristatic and bactericidal properties. PMID:762408

  15. Dissociation, aggregation of sesame alpha-globulin in nonionic detergent solution.

    PubMed

    Lakshmi, T S; Nandi, P K

    1978-10-01

    Nonionic detergents Triton X-100 and Brij 36T induce dissociation and aggregation of the protein sesame alpha-globulin above the critical micelle concentrations (cmc) of the detergents. Spectrophotometric titration in Triton shows no change in the pKInt value of the tyrosyl groups at 1x10-3 M detergent where both dissociation and aggregation of the protein are observed. Fluorescence measurement does not indicate any change in the environment of the tryptophan groups of the protein in Brij. Viscosity measurements show no major conformational change of the protein in the detergent solution. Binding measurements suggest that perhaps micelles of the detergent predominantly bind to the protein. The detergent micelles preferentially bind to the exposed hydrophobic surfaces of the protein subunits. The association of the protein detergent complex through electrostatic interaction is probably responsible for the formation of the aggregates.

  16. Solubilization of glycoproteins of envelope viruses by detergents

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Berezin, V.E.; Zaides, V.M.; Artamsnov, A.F.

    1986-11-20

    The action of a number of known ionic and nonionic detergents, as well as the new nonionic detergent MESK, on envelope viruses was investigated. It was shown that the nonionic detergents MESK, Triton X-100, and octyl-..beta..-D-glucopyranoside selectively solubilize the outer glycoproteins of the virus particles. The nonionic detergent MESK has the mildest action. Using MESK, purified glycoproteins of influenza, parainfluenza, Venezuelan equine encephalomyelitis, vesicular stomatitis, rabies, and herpes viruses were obtained. The procedure for obtaining glycoproteins includes incubation of the virus suspension with the detergent MESK, removal of subvirus structures by centrifuging, and purification of glycoproteins from detergents by dialysis.more » Isolated glycoproteins retain a native structure and biological activity and possess high immunogenicity. The detergent MESK is promising for laboratory tests and with respect to the production of subunit vaccines.« less

  17. Effectiveness of dishwashing liquids in removing chlorothalonil and chlorpyrifos residues from cherry tomatoes.

    PubMed

    Wang, Zhiwei; Huang, Jiexun; Chen, Jinyuan; Li, Feili

    2013-08-01

    Washing is the most practical way to remove pesticide residues in fruits and vegetables. Two commonly used kitchen dishwashing liquids (detergents) in Chinese market were tested for enhanced removal of chlorpyrifos (CHP) and chlorothalonil (CHT) in cherry tomatoes by soaking the cherry tomatoes in the detergent solutions. The critical micelle concentrations of detergent A and detergent B were about 250 mg L(-1) and 444 mg L(-1), respectively. Detergent A had a higher solubilizing ability for pesticides and hence washing effectiveness than detergent B. The apparent solubility of CHP increased with increasing detergent concentration, while that of CHT remained comparatively invariant independent of detergent concentration within the tested range. The apparent solubility of CHP was also consistently higher in solutions of both detergents as compared to CHT. Due probably to its lower logKow value, CHT was more readily washed off cherry tomatoes than CHP. In terms of washing, a duration of 10-20 min was sufficient for removal of pesticides on cherry tomatoes in distilled water and detergent solutions. The effectiveness of removing pesticides increased with increasing detergent concentration from 50 mg L(-1) to 5 g L(-1), with up to 80% CHT and 42% CHP removed. Multiple washing further increased pesticide removal. Adding 10% acetic acid to lower pH or increasing washing temperature favored pesticide removal, but 10% NaCl produced the shielding effect and substantially reduced the effectiveness of detergent A for pesticide removal. Copyright © 2013 Elsevier Ltd. All rights reserved.

  18. Laundry detergents: an overview.

    PubMed

    Bajpai, Divya; Tyagi, V K

    2007-01-01

    Nowadays laundry detergents are becoming increasingly popular as they can be metered automatically into the washing machine, impart softness, antistaticness, resiliency to fabrics, mild to eyes and skins and shows good dispersibility in water. Because it is consumed when it is used, the sale of laundry detergent is a rather large business. There are many different kinds or brands of laundry detergent sold, many of them claiming some special qualities as selling points. A Laundry detergent composition is a formulated mixture of raw materials that can be classified into different types based on their properties and function in the final product. The different classes of raw materials are surfactants, builders, bleaching agents, enzymes, and minors which remove dirt, stain, and soil from surfaces or textiles gave them pleasant feel and odour. The physico-chemical properties of surfactants make them suitable for laundry purposes. Laundry detergent has traditionally been a powdered or granular solid, but the use of liquid laundry detergents has gradually increased over the years, and these days use of liquid detergent equals or even exceeds use of solid detergent. This review paper describes the history, composition, types, mechanism, consumption, environmental effects and consumption of laundry detergents.

  19. Evaluation of a New Lipase from Staphylococcus sp. for Detergent Additive Capability

    PubMed Central

    Chauhan, Mamta; Chauhan, Rajinder Singh; Garlapati, Vijay Kumar

    2013-01-01

    Lipases are the enzymes of choice for laundry detergent industries owing to their triglyceride removing ability from the soiled fabric which eventually reduces the usage of phosphate-based chemical cleansers in the detergent formulation. In the present study, a partially purified bacterial lipase from Staphylococcus arlettae JPBW-1 isolated from the rock salt mine has been assessed for its triglyceride removing ability by developing a presoak solution so as to use lipase as an additive in laundry detergent formulations. The effects of selected surfactants, commercial detergents, and oxidizing agents on lipase stability were studied in a preliminary evaluation for its further usage in the industrial environment. Partially purified lipase has shown good stability in presence of surfactants, commercial detergents, and oxidizing agents. Washing efficiency has been found to be enhanced while using lipase with 0.5% nonionic detergent than the anioinic detergent. The wash performance using 0.5% wheel with 40 U lipase at 40°C in 45 min results in maximum oil removal (62%) from the soiled cotton fabric. Hence, the present study opens the new era in enzyme-based detergent sector for formulation of chemical-free detergent using alkaline bacterial lipase. PMID:24106703

  20. Evaluation of a new lipase from Staphylococcus sp. for detergent additive capability.

    PubMed

    Chauhan, Mamta; Chauhan, Rajinder Singh; Garlapati, Vijay Kumar

    2013-01-01

    Lipases are the enzymes of choice for laundry detergent industries owing to their triglyceride removing ability from the soiled fabric which eventually reduces the usage of phosphate-based chemical cleansers in the detergent formulation. In the present study, a partially purified bacterial lipase from Staphylococcus arlettae JPBW-1 isolated from the rock salt mine has been assessed for its triglyceride removing ability by developing a presoak solution so as to use lipase as an additive in laundry detergent formulations. The effects of selected surfactants, commercial detergents, and oxidizing agents on lipase stability were studied in a preliminary evaluation for its further usage in the industrial environment. Partially purified lipase has shown good stability in presence of surfactants, commercial detergents, and oxidizing agents. Washing efficiency has been found to be enhanced while using lipase with 0.5% nonionic detergent than the anioinic detergent. The wash performance using 0.5% wheel with 40 U lipase at 40°C in 45 min results in maximum oil removal (62%) from the soiled cotton fabric. Hence, the present study opens the new era in enzyme-based detergent sector for formulation of chemical-free detergent using alkaline bacterial lipase.

  1. Correlating Detergent Fiber Analysis and Dietary Fiber Analysis Data for Corn Stover

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wolfrum, E. J.; Lorenz, A. J.; deLeon, N.

    There exist large amounts of detergent fiber analysis data [neutral detergent fiber (NDF), acid detergent fiber (ADF), acid detergent lignin (ADL)] for many different potential cellulosic ethanol feedstocks, since these techniques are widely used for the analysis of forages. Researchers working in the area of cellulosic ethanol are interested in the structural carbohydrates in a feedstock (principally glucan and xylan), which are typically determined by acid hydrolysis of the structural fraction after multiple extractions of the biomass. These so-called dietary fiber analysis methods are significantly more involved than detergent fiber analysis methods. The purpose of this study was to determinemore » whether it is feasible to correlate detergent fiber analysis values to glucan and xylan content determined by dietary fiber analysis methods for corn stover. In the detergent fiber analysis literature cellulose is often estimated as the difference between ADF and ADL, while hemicellulose is often estimated as the difference between NDF and ADF. Examination of a corn stover dataset containing both detergent fiber analysis data and dietary fiber analysis data predicted using near infrared spectroscopy shows that correlations between structural glucan measured using dietary fiber techniques and cellulose estimated using detergent techniques, and between structural xylan measured using dietary fiber techniques and hemicellulose estimated using detergent techniques are high, but are driven largely by the underlying correlation between total extractives measured by fiber analysis and NDF/ADF. That is, detergent analysis data is correlated to dietary fiber analysis data for structural carbohydrates, but only indirectly; the main correlation is between detergent analysis data and solvent extraction data produced during the dietary fiber analysis procedure.« less

  2. Harmful effect of detergents on lipase.

    PubMed

    Fatima, Sadaf; Ajmal, Rehan; Badr, Gamal; Khan, Rizwan H

    2014-11-01

    In order to study effects of detergents at molecular level, we have done activity measurements of wheat germ lipase in increasing concentration of some commercial detergents. Conformational changes in protein structure using circular dichroism and fluorescence spectroscopy were studied in increasing concentration of sodium dodecyl sulfate. Our study proves that detergents may lead to loss of enzymatic activity and structure of plant enzymes. Since detergents are common source of pollution in water bodies and the water from these resources can be used in fields, our study may prove helpful in creating awareness about harmful action of detergents.

  3. The Effect of Detergents on the Morphology and Immunomodulatory Activity of Malassezia furfur

    PubMed Central

    Kim, Su-Han; Ko, Hyun-Chang; Kwon, Kyung-Sool; Oh, Chang-Keun

    2009-01-01

    Background Several workers have found that Malassezia are capable of suppressing cytokine release and downregulating the phagocytic function of monocytes. But lipid-depleted Malassezia furfur (M. furfur) extracts have also been shown to induce increased production of TNF-α, IL-6 and IL-1β in monocytes. We thought that the detergents in shampoos or soaps could change the composition of the lipid in the M. furfur cell wall. Objective We studied whether detergents affect the morphology of M. furfur and if the inflammatory cytokine profiles change in the monocytes treated with detergent-treated M. furfur. Methods Commonly used detergents such as sodium lauryl sulfate, ammonium lauryl sulfate and tween-80 were respectively added to the modified Leeming-Notman's media. M. furfur was cultivated in each media (detergent-added or untreated). Thereafter, the surface morphology of the yeast was evaluated by scanning and transmission electron microscopy. The cytokine profiles of monocytes, which were treated by M. furfur with or without detergents, were also evaluated. Results The detergent-treated M. furfur were similar to the lipid-extracted form of M. furfur on the electron microscopic study, with a recessed, withered surface and with thinner and rather electron transparent cell walls than the detergent-untreated M. furfur. The levels of TNF-α were higher in monocytes treated with detergent-treated Malassezia than that in the monocytes treated with the detergent-untreated Malassezia (p<0.05). Conclusion According to the findings in this study, it could be inferred that the detergents in shampoos or soaps affect the lipid layers of the Malassezia cell wall and these lipid-extracted Malassezia induce or aggravate some inflammatory conditions. But to correlate the relationship between detergents and Malassezia-associated diseases, in vivo experiments that will focus on short-term contact with detergents in real life conditions should be done. PMID:20523770

  4. Laundry pod and non-pod detergent related emergency department visits occurring in children in the USA.

    PubMed

    Swain, Thomas A; McGwin, Gerald; Griffin, Russell

    2016-12-01

    Previous studies have reported that children are at risk of severe injuries from exposure to laundry detergent pods. For the first time, this study sought to compare demographic and exposure characteristics and risk among children exposed to pod and non-pod laundry detergents presenting to emergency departments (EDs). Data from the National Electronic Injury Surveillance System (NEISS) from 2012-2014 were used. All observations with injuries involving laundry detergent (NEISS code 0949) were included in this study. The χ 2 test was used for bivariate analysis and logistic regression was used to determine the OR and 95% CI of hospitalisation for pod related versus non-pod laundry detergent exposures. From 2012-2014, there were an estimated 26 062 non-pod and 9814 pod laundry detergent related exposures among those aged 18 years and younger. For pod detergent, children aged 0-5 years had the most injuries. Poisoning (71.3%) was the most common diagnosis for pod detergent while contact dermatitis (72.2%) was most common for non-pod detergent. Hospitalisation occurred in 12.5% of pod detergent cases and just 3.0% of non-pod cases. Compared with non-pod detergent, those exposed to pod detergent were 4 times as likely to be hospitalised (OR 4.02; 95% CI 1.96 to 8.24). A greater effort should be made to appropriately educate the public about the dangers of laundry detergents, specifically pods, so a safe home environment can be established. While new regulations such as childproof containers, opaque packaging, and less appealing and colourful pods could reduce the number of pod related ED visits for children, caregivers should store detergents, along with other chemicals, in a secure location where children cannot easily access them. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  5. Detergent effects on enzyme activity and solubilization of lipid bilayer membranes.

    PubMed

    Womack, M D; Kendall, D A; MacDonald, R C

    1983-09-07

    Over 50 detergents were tested to establish which would be most effective in releasing proteins from membrane-bounded compartments without denaturing them. Various concentrations each of detergent were tested for two activities: (1) solubilization of egg phospholipid liposomes as measured by reduction of turbidity and (2) effect of detergent concentration on the activities of soluble, hydrolytic enzymes. Those detergents most effective in solubilizing 0.2% lipid and least detrimental to enzymes were five pure, synthetic compounds recently introduced: CHAPS, CHAPSO, Zwittergents 310 and 312, and octylglucoside. Industrial detergents were generally much inferior, insofar as they solubilized membranes inefficiently and/or inactivated certain hydrolytic enzymes readily. The five detergents were characterized by (a) an unusually high critical micelle concentration and (b) a preference for forming mixed micelles with lipids instead of forming pure micelles, as indicated by an ability to solubilize lipid at concentrations of detergent significantly below the critical micelle concentration. This characteristic permits solubilization of high concentrations of membrane below the critical micelle concentration of the detergent so that protein denaturation is minimized. A generally applicable guideline that emerged from this study is that detergents should be used at approximately their critical micelle concentration which should not be exceeded by the concentration of membrane. Similar considerations should apply to the use of detergents in purifying and reconstituting intrinsic membrane proteins.

  6. NMR spectroscopic and analytical ultracentrifuge analysis of membrane protein detergent complexes.

    PubMed

    Maslennikov, Innokentiy; Kefala, Georgia; Johnson, Casey; Riek, Roland; Choe, Senyon; Kwiatkowski, Witek

    2007-11-08

    Structural studies of integral membrane proteins (IMPs) are hampered by inherent difficulties in their heterologous expression and in the purification of solubilized protein-detergent complexes (PDCs). The choice and concentrations of detergents used in an IMP preparation play a critical role in protein homogeneity and are thus important for successful crystallization. Seeking an effective and standardized means applicable to genomic approaches for the characterization of PDCs, we chose 1D-NMR spectroscopic analysis to monitor the detergent content throughout their purification: protein extraction, detergent exchange, and sample concentration. We demonstrate that a single NMR measurement combined with a SDS-PAGE of a detergent extracted sample provides a useful gauge of the detergent's extraction potential for a given protein. Furthermore, careful monitoring of the detergent content during the process of IMP production allows for a high level of reproducibility. We also show that in many cases a simple sedimentation velocity measurement provides sufficient data to estimate both the oligomeric state and the detergent-to-protein ratio in PDCs, as well as to evaluate the homogeneity of the samples prior to crystallization screening. The techniques presented here facilitate the screening and selection of the extraction detergent, as well as help to maintain reproducibility in the detergent exchange and PDC concentration procedures. Such reproducibility is particularly important for the optimization of initial crystallization conditions, for which multiple purifications are routinely required.

  7. NMR spectroscopic and analytical ultracentrifuge analysis of membrane protein detergent complexes

    PubMed Central

    Maslennikov, Innokentiy; Kefala, Georgia; Johnson, Casey; Riek, Roland; Choe, Senyon; Kwiatkowski, Witek

    2007-01-01

    Background Structural studies of integral membrane proteins (IMPs) are hampered by inherent difficulties in their heterologous expression and in the purification of solubilized protein-detergent complexes (PDCs). The choice and concentrations of detergents used in an IMP preparation play a critical role in protein homogeneity and are thus important for successful crystallization. Results Seeking an effective and standardized means applicable to genomic approaches for the characterization of PDCs, we chose 1D-NMR spectroscopic analysis to monitor the detergent content throughout their purification: protein extraction, detergent exchange, and sample concentration. We demonstrate that a single NMR measurement combined with a SDS-PAGE of a detergent extracted sample provides a useful gauge of the detergent's extraction potential for a given protein. Furthermore, careful monitoring of the detergent content during the process of IMP production allows for a high level of reproducibility. We also show that in many cases a simple sedimentation velocity measurement provides sufficient data to estimate both the oligomeric state and the detergent-to-protein ratio in PDCs, as well as to evaluate the homogeneity of the samples prior to crystallization screening. Conclusion The techniques presented here facilitate the screening and selection of the extraction detergent, as well as help to maintain reproducibility in the detergent exchange and PDC concentration procedures. Such reproducibility is particularly important for the optimization of initial crystallization conditions, for which multiple purifications are routinely required. PMID:17988403

  8. Membrane protein stability can be compromised by detergent interactions with the extramembranous soluble domains

    PubMed Central

    Yang, Zhengrong; Wang, Chi; Zhou, Qingxian; An, Jianli; Hildebrandt, Ellen; Aleksandrov, Luba A; Kappes, John C; DeLucas, Lawrence J; Riordan, John R; Urbatsch, Ina L; Hunt, John F; Brouillette, Christie G

    2014-01-01

    Detergent interaction with extramembranous soluble domains (ESDs) is not commonly considered an important determinant of integral membrane protein (IMP) behavior during purification and crystallization, even though ESDs contribute to the stability of many IMPs. Here we demonstrate that some generally nondenaturing detergents critically destabilize a model ESD, the first nucleotide-binding domain (NBD1) from the human cystic fibrosis transmembrane conductance regulator (CFTR), a model IMP. Notably, the detergents show equivalent trends in their influence on the stability of isolated NBD1 and full-length CFTR. We used differential scanning calorimetry (DSC) and circular dichroism (CD) spectroscopy to monitor changes in NBD1 stability and secondary structure, respectively, during titration with a series of detergents. Their effective harshness in these assays mirrors that widely accepted for their interaction with IMPs, i.e., anionic > zwitterionic > nonionic. It is noteworthy that including lipids or nonionic detergents is shown to mitigate detergent harshness, as will limiting contact time. We infer three thermodynamic mechanisms from the observed thermal destabilization by monomer or micelle: (i) binding to the unfolded state with no change in the native structure (all detergent classes); (ii) native state binding that alters thermodynamic properties and perhaps conformation (nonionic detergents); and (iii) detergent binding that directly leads to denaturation of the native state (anionic and zwitterionic). These results demonstrate that the accepted model for the harshness of detergents applies to their interaction with an ESD. It is concluded that destabilization of extramembranous soluble domains by specific detergents will influence the stability of some IMPs during purification. PMID:24652590

  9. Detection of antibiotics in goat's milk: effect of detergents on the response of microbial inhibitor tests.

    PubMed

    Romero, Tamara; Beltrán, María Carmen; Althaus, Rafael Lisandro; Molina, María Pilar

    2014-08-01

    The aim of the study was to evaluate the interference of acid and alkaline detergents employed in the cleaning of milking equipment of caprine dairy farms on the performance of microbial tests used in antibiotic control (BRT MRL, Delvotest MCS, and Eclipse 100). Eight concentrations of commercial detergents, five acid (0-0.25%) and five alkaline (0-1%) were add to antimicrobial-free goat's milk to evaluate the detergent effect on the response of microbial inhibitor tests. To evaluate the effect of detergents on the detection capability of microbial tests two detergents at 0.5 ml/l (one acid and one basic) and eight concentrations of four β-lactam antibiotics (ampicillin, amoxicillin, cloxacillin and benzylpenicillin) were used. Milk without detergents was used as control. The spiked samples were analysed twelve times by three microbial tests. The results showed that the presence of acid detergents did not affect the response of microbial tests for any of the concentrations tested. However, at concentrations equal to or greater than 2 ml/l alkaline detergents positive results were found in microbial tests (16.7-100%). The detection limits of the screening tests for penicillins were not modified substantially by the presence of detergents. In general, the presence of acid and alkaline detergents in goat's milk did not produce a great interference in the microbial tests, only high concentrations of detergents could cause non-compliant results, but these concentrations are difficult to find in practice if proper cleaning procedures are applied in goat dairy farms.

  10. Detergent-mediated protein aggregation

    PubMed Central

    Neale, Chris; Ghanei, Hamed; Holyoake, John; Bishop, Russell E.; Privé, Gilbert G.; Pomès, Régis

    2016-01-01

    Because detergents are commonly used to solvate membrane proteins for structural evaluation, much attention has been devoted to assessing the conformational bias imparted by detergent micelles in comparison to the native environment of the lipid bilayer. Here, we conduct six 500-ns simulations of a system with >600,000 atoms to investigate the spontaneous self assembly of dodecylphosphocholine detergent around multiple molecules of the integral membrane protein PagP. This detergent formed equatorial micelles in which acyl chains surround the protein’s hydrophobic belt, confirming existing models of the detergent solvation of membrane proteins. In addition, unexpectedly, the extracellular and periplasmic apical surfaces of PagP interacted with the headgroups of detergents in other micelles 85 and 60% of the time, respectively, forming complexes that were stable for hundreds of nanoseconds. In some cases, an apical surface of one molecule of PagP interacted with an equatorial micelle surrounding another molecule of PagP. In other cases, the apical surfaces of two molecules of PagP simultaneously bound a neat detergent micelle. In these ways, detergents mediated the non-specific aggregation of folded PagP. These simulation results are consistent with dynamic light scattering experiments, which show that, at detergent concentrations ≥600 mM, PagP induces the formation of large scattering species that are likely to contain many copies of the PagP protein. Together, these simulation and experimental results point to a potentially generic mechanism of detergent-mediated protein aggregation. PMID:23466535

  11. 40 CFR 80.141 - Interim detergent gasoline program.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...) “Carburetor Cleanliness Test Procedure, State-of-the-Art Summary, Report: 1973-1981”, Coordinating Research... ultimate consumer; (ii) All additized post-refinery component (PRC); and (iii) All detergent additives sold... who manufacture, supply, or transfer detergent additives or detergent-additized post-refinery...

  12. Identification of detergents for forensic fiber analysis.

    PubMed

    Heider, Emily C; Mujumdar, Nirvani; Campiglia, Andres D

    2016-11-01

    Trace fibers are an important form of trace evidence, and identification of exogenous substances on textile fibers provides valuable information about the origin of the fiber. Laundering textiles can provide a unique fluorescent spectral signature of the whitening agent in the detergent that adsorbs to the fiber. Using fluorescence microscopy, the spectral characteristics of seven detergents adsorbed to single fibers drawn from laundered textiles were investigated, and principal component analysis of clusters was used to characterize the type of detergent on the fiber. On dyed nylon fibers, spectra from eight different detergent pairs could be resolved and washed validation fibers correctly classified. On dyed acrylic fibers, five different detergent pairs could be resolved and identified. Identification of the detergent type may prove useful in matching a trace fiber to its bulk specimen of origin.

  13. Effect of dodecyl maltoside detergent on rhodopsin stability and function.

    PubMed

    Ramon, Eva; Marron, Jordi; del Valle, Luis; Bosch, Laia; Andrés, Anna; Manyosa, Joan; Garriga, Pere

    2003-12-01

    Detergent-solubilized bovine rhodopsin produces mixed detergent/lipid/protein micelles. The effect of dodecyl maltoside detergent on the thermal stability of dark-state rhodopsin, and upon formation of the different intermediates after rhodopsin photobleaching (metarhodopsin II and metarhodopsin III), and upon transducin activation has been studied. No significant effect is observed for the thermal stability of dark-state rhodopsin in the range of detergent concentrations studied, but a decrease in the stability of metarhodopsin II and an increase in metarhodopsin III formation is observed with decreasing detergent concentrations. The transducin activation process is also affected by the presence of detergent indicating that this process is dependent on the lipid micro-environment and membrane fluidity, and this stresses the importance of the native lipid environment in rhodopsin normal function.

  14. Detergent enhances binding of a secreted HLA-A2 molecule to solid phase peptides.

    PubMed

    Tussey, L G; Frelinger, J A

    1991-11-01

    We have constructed a secreted analogue (sA2) of the human class I molecule HLA-A2. sA2 was affinity purified both in the presence and absence of detergent and the effects of detergent on the magnitude and specificity of A2 binding to solid phase peptides tested. sA2 purified in the presence of detergent and detergent-solubilized A2 are shown to function comparably in the binding of the synthetic peptide M.Y + 57-68, a known T-cell epitope derived from the influenza A matrix protein. The molecules binding to M.Y + 57-68 typically represent 8% to 10% of the added protein. In contrast, less than 1% of sA2 protein purified in the absence of detergent binds M.Y + 57-68. This reduced binding is not due to a change in the affinity of sA2 for M.Y + 57-68. Addition of detergent at various stages of the purification and iodination procedures indicates that the longer the sA2 molecules are exposed to detergent the better they bind. However, the concentration of detergent during the actual binding assay does not appear to be critical. We also find that while the sA2-detergent and the sA2-no detergent molecules differ in the extent to which they bind various peptides, they do not differ in their patterns of binding. We conclude that detergent probably does not influence the specificity of class I/peptide binding but does increase the number of sA2 molecules that can participate in the binding of peptide either by generating and stabilizing "empty" sA2 molecules or by stabilizing a structure that is more amenable to binding peptide.

  15. Deuterated detergents for structural and functional studies of membrane proteins: Properties, chemical synthesis and applications.

    PubMed

    Hiruma-Shimizu, Kazumi; Shimizu, Hiroki; Thompson, Gary S; Kalverda, Arnout P; Patching, Simon G

    2015-01-01

    Detergents are amphiphilic compounds that have crucial roles in the extraction, purification and stabilization of integral membrane proteins and in experimental studies of their structure and function. One technique that is highly dependent on detergents for solubilization of membrane proteins is solution-state NMR spectroscopy, where detergent micelles often serve as the best membrane mimetic for achieving particle sizes that tumble fast enough to produce high-resolution and high-sensitivity spectra, although not necessarily the best mimetic for a biomembrane. For achieving the best quality NMR spectra, detergents with partial or complete deuteration can be used, which eliminate interfering proton signals coming from the detergent itself and also eliminate potential proton relaxation pathways and strong dipole-dipole interactions that contribute line broadening effects. Deuterated detergents have also been used to solubilize membrane proteins for other experimental techniques including small angle neutron scattering and single-crystal neutron diffraction and for studying membrane proteins immobilized on gold electrodes. This is a review of the properties, chemical synthesis and applications of detergents that are currently commercially available and/or that have been synthesized with partial or complete deuteration. Specifically, the detergents are sodium dodecyl sulphate (SDS), lauryldimethylamine-oxide (LDAO), n-octyl-β-D-glucoside (β-OG), n-dodecyl-β-D-maltoside (DDM) and fos-cholines including dodecylphosphocholine (DPC). The review also considers effects of deuteration, detergent screening and guidelines for detergent selection. Although deuterated detergents are relatively expensive and not always commercially available due to challenges associated with their chemical synthesis, they will continue to play important roles in structural and functional studies of membrane proteins, especially using solution-state NMR.

  16. [Response of the algae Gymnodinium kovalevskii (Dinophyta) to exposure to synthetic detergents and distillation].

    PubMed

    Aĭzdaĭcher, N A

    2000-01-01

    The effects of synthetic detergents and combined effects of synthetic detergents and water freshening on growth characteristics of the alga Gymnodinium kovalevskii (Dinophyta) were studied. Low concentrations of synthetic detergents (0.1 and 1.0 mg/l) stimulated the algal growth. Elevated concentrations inhibited cell division, affected their motility and induced morphological changes. Contamination with synthetic detergents adversely affected the adaptation plasticity of algae with respect to salinity.

  17. Designing Mixed Detergent Micelles for Uniform Neutron Contrast

    DOE PAGES

    Oliver, Ryan C.; Pingali, Sai Venkatesh; Urban, Volker S.

    2017-09-29

    Micelle-forming detergents provide an amphipathic environment that mimics lipid bilayers and are important tools used to solubilize and stabilize membrane proteins in solution for in vitro structural investigations. Small-angle neutron scattering (SANS) performed at the neutron contrast match point of detergent molecules allows observing the scattering signal from membrane proteins unobstructed by contributions from the detergent. However, we show here that even for a perfectly average-contrast matched detergent there arises significant core-shell scattering from the contrast difference between aliphatic detergent tails and hydrophilic head groups. This residual signal at the average detergent contrast match point interferes with interpreting structural datamore » of membrane proteins. This complication is often made worse by the presence of excess empty (protein-free) micelles. Here, we present an approach for the rational design of mixed micelles containing a deuterated detergent analog, which eliminates neutron contrast between core and shell, and allows the micelle scattering to be fully contrast matched to unambiguously resolve membrane protein structure using solution SANS.« less

  18. Designing Mixed Detergent Micelles for Uniform Neutron Contrast

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Oliver, Ryan C.; Pingali, Sai Venkatesh; Urban, Volker S.

    Micelle-forming detergents provide an amphipathic environment that mimics lipid bilayers and are important tools used to solubilize and stabilize membrane proteins in solution for in vitro structural investigations. Small-angle neutron scattering (SANS) performed at the neutron contrast match point of detergent molecules allows observing the scattering signal from membrane proteins unobstructed by contributions from the detergent. However, we show here that even for a perfectly average-contrast matched detergent there arises significant core-shell scattering from the contrast difference between aliphatic detergent tails and hydrophilic head groups. This residual signal at the average detergent contrast match point interferes with interpreting structural datamore » of membrane proteins. This complication is often made worse by the presence of excess empty (protein-free) micelles. Here, we present an approach for the rational design of mixed micelles containing a deuterated detergent analog, which eliminates neutron contrast between core and shell, and allows the micelle scattering to be fully contrast matched to unambiguously resolve membrane protein structure using solution SANS.« less

  19. Designer lipid-like peptides: a class of detergents for studying functional olfactory receptors using commercial cell-free systems.

    PubMed

    Corin, Karolina; Baaske, Philipp; Ravel, Deepali B; Song, Junyao; Brown, Emily; Wang, Xiaoqiang; Wienken, Christoph J; Jerabek-Willemsen, Moran; Duhr, Stefan; Luo, Yuan; Braun, Dieter; Zhang, Shuguang

    2011-01-01

    A crucial bottleneck in membrane protein studies, particularly G-protein coupled receptors, is the notorious difficulty of finding an optimal detergent that can solubilize them and maintain their stability and function. Here we report rapid production of 12 unique mammalian olfactory receptors using short designer lipid-like peptides as detergents. The peptides were able to solubilize and stabilize each receptor. Circular dichroism showed that the purified olfactory receptors had alpha-helical secondary structures. Microscale thermophoresis suggested that the receptors were functional and bound their odorants. Blot intensity measurements indicated that milligram quantities of each olfactory receptor could be produced with at least one peptide detergent. The peptide detergents' capability was comparable to that of the detergent Brij-35. The ability of 10 peptide detergents to functionally solubilize 12 olfactory receptors demonstrates their usefulness as a new class of detergents for olfactory receptors, and possibly other G-protein coupled receptors and membrane proteins.

  20. Wheat germ cell-free expression: Two detergents with a low critical micelle concentration allow for production of soluble HCV membrane proteins.

    PubMed

    Fogeron, Marie-Laure; Badillo, Aurélie; Jirasko, Vlastimil; Gouttenoire, Jérôme; Paul, David; Lancien, Loick; Moradpour, Darius; Bartenschlager, Ralf; Meier, Beat H; Penin, François; Böckmann, Anja

    2015-01-01

    Membrane proteins are notoriously difficult to express in a soluble form. Here, we use wheat germ cell-free expression in the presence of various detergents to produce the non-structural membrane proteins 2, 4B and 5A of the hepatitis C virus (HCV). We show that lauryl maltose neopentyl glycol (MNG-3) and dodecyl octaethylene glycol ether (C12E8) detergents can yield essentially soluble membrane proteins at detergent concentrations that do not inhibit the cell-free reaction. This finding can be explained by the low critical micelle concentration (CMC) of these detergents, which keeps the monomer concentrations low while at the same time providing the necessary excess of detergent concentration above CMC required for full target protein solubilization. We estimate that a tenfold excess of detergent micelles with respect to the protein concentration is sufficient for solubilization, a number that we propose as a guideline for detergent screening assays. Copyright © 2014 Elsevier Inc. All rights reserved.

  1. Designer Lipid-Like Peptides: A Class of Detergents for Studying Functional Olfactory Receptors Using Commercial Cell-Free Systems

    PubMed Central

    Corin, Karolina; Baaske, Philipp; Ravel, Deepali B.; Song, Junyao; Brown, Emily; Wang, Xiaoqiang; Wienken, Christoph J.; Jerabek-Willemsen, Moran; Duhr, Stefan; Luo, Yuan; Braun, Dieter; Zhang, Shuguang

    2011-01-01

    A crucial bottleneck in membrane protein studies, particularly G-protein coupled receptors, is the notorious difficulty of finding an optimal detergent that can solubilize them and maintain their stability and function. Here we report rapid production of 12 unique mammalian olfactory receptors using short designer lipid-like peptides as detergents. The peptides were able to solubilize and stabilize each receptor. Circular dichroism showed that the purified olfactory receptors had alpha-helical secondary structures. Microscale thermophoresis suggested that the receptors were functional and bound their odorants. Blot intensity measurements indicated that milligram quantities of each olfactory receptor could be produced with at least one peptide detergent. The peptide detergents' capability was comparable to that of the detergent Brij-35. The ability of 10 peptide detergents to functionally solubilize 12 olfactory receptors demonstrates their usefulness as a new class of detergents for olfactory receptors, and possibly other G-protein coupled receptors and membrane proteins. PMID:22132066

  2. A high-throughput differential filtration assay to screen and select detergents for membrane proteins

    PubMed Central

    Vergis, James M.; Purdy, Michael D.; Wiener, Michael C.

    2015-01-01

    Structural studies on integral membrane proteins are routinely performed on protein–detergent complexes (PDCs) consisting of purified protein solubilized in a particular detergent. Of all the membrane protein crystal structures solved to date, a subset of only four detergents has been used in more than half of these structures. Unfortunately, many membrane proteins are not well behaved in these four detergents and/or fail to yield well-diffracting crystals. Identification of detergents that maintain the solubility and stability of a membrane protein is a critical step and can be a lengthy and “protein-expensive” process. We have developed an assay that characterizes the stability and size of membrane proteins exchanged into a panel of 94 commercially available and chemically diverse detergents. This differential filtration assay (DFA), using a set of filtered microplates, requires sub-milligram quantities of purified protein and small quantities of detergents and other reagents and is performed in its entirety in several hours. PMID:20667442

  3. Concentrated liquid detergent pod ingestion in children.

    PubMed

    Sidhu, Natasha; Jaeger, Matthew W

    2014-12-01

    Concentrated liquid detergent pods are an emerging public health hazard, especially in pediatric patients. Ingestion is a more common route of exposure for liquid detergent pods compared with non-pod detergents and it tends to be associated with more severe adverse effects. We present 3 cases that demonstrate the varied clinical symptoms resulting from detergent pod ingestion. These cases not only demonstrate findings such as gastrointestinal and respiratory symptoms but also show more rare neurological symptoms. The cases highlight the dangers of concentrated liquid detergent pod ingestion. To help prevent further life-threatening injuries, there is a need for more consumer information and provider knowledge about the potential adverse complications.

  4. Perturbations of Native Membrane Protein Structure in Alkyl Phosphocholine Detergents: A Critical Assessment of NMR and Biophysical Studies

    PubMed Central

    2018-01-01

    Membrane proteins perform a host of vital cellular functions. Deciphering the molecular mechanisms whereby they fulfill these functions requires detailed biophysical and structural investigations. Detergents have proven pivotal to extract the protein from its native surroundings. Yet, they provide a milieu that departs significantly from that of the biological membrane, to the extent that the structure, the dynamics, and the interactions of membrane proteins in detergents may considerably vary, as compared to the native environment. Understanding the impact of detergents on membrane proteins is, therefore, crucial to assess the biological relevance of results obtained in detergents. Here, we review the strengths and weaknesses of alkyl phosphocholines (or foscholines), the most widely used detergent in solution-NMR studies of membrane proteins. While this class of detergents is often successful for membrane protein solubilization, a growing list of examples points to destabilizing and denaturing properties, in particular for α-helical membrane proteins. Our comprehensive analysis stresses the importance of stringent controls when working with this class of detergents and when analyzing the structure and dynamics of membrane proteins in alkyl phosphocholine detergents. PMID:29488756

  5. Irritancy potential of 17 detergents used commonly by the Indian household.

    PubMed

    Austoria, A J; Lakshmi, Chembolli; Srinivas, C R; Anand, C V; Mathew, A C

    2010-01-01

    Detergents are used by almost every household in the developed and developing world. Soap and most detergents are anionic surfactants and attack the horny layer of the skin and increase its permeability with little or no inflammatory change and may result in hand eczema, which is very distressing and incapacitating. To evaluate the irritant potential of common household detergents (laundry and dish wash) used by the Indian population using a 24-hour patch test and to convincingly educate the patients on the detergents less likely to cause irritation in the particular individual. Seventeen commonly used detergents found in Indian market were included in the study, of which, 12 were laundry detergents (powders--seven, bar soap--five) and five were dish wash detergents (powder--one, liquid--one, bar soap--three). The irritant potential of the 17 detergents were evaluated in 30 volunteers. Thirty microliters of each of the detergent bar solutions, distilled water (negative control), and 20% SDS (positive control) were applied to Finn chambers with a micropipette and occluded for 24 hours. Erythema, scaling, and edema were graded in comparison to the reaction at the negative control site (distilled water) for each volunteer separately. The scoring of erythema/dryness and wrinkling on a 0-4 point scale and edema on another 0-4 point scale was based on the Draize scale. The pH of each of the detergent solutions was determined using litmus papers (Indikrom papers from Qualigens fine chemicals). The difference between detergents (F value) was significant for erythema/dryness and wrinkling (F = 3.374; p = 0.000), but not significant for edema (F = 1.297; p = 0.194). [Table 2] lists the means for erythema/dryness and wrinkling, and edema. The F value of the totals of the means for erythema/dryness and wrinkling and edema was significant (F = 2.495; p = 0.001). The pH of all the detergents was found to be alkaline except Pril utensil cleaner which tested acidic (pH 6). The positive control, 20% SDS also tested acidic (pH 6). Similar to patch testing in allergic contact dermatitis, 24-hour patch testing with detergent solutions (8% w/v), will educate the patient on what detergent to avoid. This may bring down the total medication requirement and frequent hospital consultations for these patients.

  6. 40 CFR 417.160 - Applicability; description of the manufacture of liquid detergents subcategory.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... manufacture of liquid detergents subcategory. 417.160 Section 417.160 Protection of Environment ENVIRONMENTAL... CATEGORY Manufacture of Liquid Detergents Subcategory § 417.160 Applicability; description of the manufacture of liquid detergents subcategory. The provisions of this subpart are applicable to discharges...

  7. 76 FR 9013 - Agency Information Collection Activities; Proposed Collection; Comment Request; Detergent Gasoline

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-16

    ... Activities; Proposed Collection; Comment Request; Detergent Gasoline AGENCY: Environmental Protection Agency... this action are those who (1) Manufacture gasoline, post-refinery component, or detergent additives, (2) blend detergent additives into gasoline or post-refinery component, or (3) transport or receive a...

  8. 40 CFR 417.150 - Applicability; description of the manufacture of spray dried detergents subcategory.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... manufacture of spray dried detergents subcategory. 417.150 Section 417.150 Protection of Environment... POINT SOURCE CATEGORY Manufacture of Spray Dried Detergents Subcategory § 417.150 Applicability; description of the manufacture of spray dried detergents subcategory. The provisions of this subpart are...

  9. 40 CFR 417.180 - Applicability; description of the manufacture of drum dried detergents subcategory.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... manufacture of drum dried detergents subcategory. 417.180 Section 417.180 Protection of Environment... POINT SOURCE CATEGORY Manufacture of Drum Dried Detergents Subcategory § 417.180 Applicability; description of the manufacture of drum dried detergents subcategory. The provisions of this subpart are...

  10. 40 CFR 80.156 - Liability for violations of the interim detergent program controls and prohibitions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ..., or detergent-additized post-refinery component satisfied relevant requirements when it left their... detergent satisfied all relevant requirements when it left the detergent manufacturer's control; and (B... manufactured. (2) The test results must accurately establish that, when it left the manufacturer's control, the...

  11. 40 CFR 80.163 - Detergent certification options.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 16 2010-07-01 2010-07-01 false Detergent certification options. 80... options. To be used to satisfy the detergency requirements under § 80.161(a), a detergent additive must be certified in accordance with the requirements of one or more of the options and suboptions described in this...

  12. 40 CFR 417.170 - Applicability; description of the manufacture of detergents by dry blending subcategory.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... manufacture of detergents by dry blending subcategory. 417.170 Section 417.170 Protection of Environment... POINT SOURCE CATEGORY Manufacture of Detergents by Dry Blending Subcategory § 417.170 Applicability; description of the manufacture of detergents by dry blending subcategory. The provisions of this subpart are...

  13. 40 CFR 417.190 - Applicability; description of the manufacture of detergent bars and cakes subcategory.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... manufacture of detergent bars and cakes subcategory. 417.190 Section 417.190 Protection of Environment... POINT SOURCE CATEGORY Manufacture of Detergent Bars and Cakes Subcategory § 417.190 Applicability; description of the manufacture of detergent bars and cakes subcategory. The provisions of this subpart are...

  14. 40 CFR 80.156 - Liability for violations of the interim detergent program controls and prohibitions.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... base gasoline component, the detergent component, or the detergent-additized post-refinery component of... component of any post-refinery component or gasoline in the storage tank containing gasoline found to be in... evidence, that the gasoline or detergent carrier caused the violation. (2) Post-refinery component non...

  15. 40 CFR 80.161 - Detergent additive certification program.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... requirements. For a detergent additive package to be certified as eligible for use by detergent blenders in...: (i) The compositional data required under § 79.21(a) of this chapter shall include the information... chapter shall be reported to EPA in units of gallons of detergent additive package per 1000 gallons of...

  16. 40 CFR 80.161 - Detergent additive certification program.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... requirements. For a detergent additive package to be certified as eligible for use by detergent blenders in...: (i) The compositional data required under § 79.21(a) of this chapter shall include the information... chapter shall be reported to EPA in units of gallons of detergent additive package per 1000 gallons of...

  17. 40 CFR 80.161 - Detergent additive certification program.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... requirements. For a detergent additive package to be certified as eligible for use by detergent blenders in...: (i) The compositional data required under § 79.21(a) of this chapter shall include the information... chapter shall be reported to EPA in units of gallons of detergent additive package per 1000 gallons of...

  18. Cellular localization and detergent dependent oligomerization of rice allene oxide synthase-1.

    PubMed

    Yoeun, Sereyvath; Kim, Jeong-Il; Han, Oksoo

    2015-01-01

    Allene oxide synthase-1 from Oryza sativa (OsAOS1) localizes to the chloroplast, but lacks a putative chloroplast targeting sequence typically found in dicot AOS. Here, kinetic parameters and the oligomerization state/subunit composition of OsAOS1 were characterized in vitro in the absence or presence of detergent micelles. The catalytic efficiency (k(cat)/K(m)) of OsAOS1 reached a maximum near the critical micelle concentration for polyoxyethylene 10 tridecyl ether. Native gel analysis showed that OsAOS1 exists as a multimer in the absence of detergent micelles. The multimeric form of OsAOS1 was stably cross-linked in the absence of detergents, while only monomeric OsAOS1 was detected in the presence of detergent micelles. Gel filtration analysis indicated that the oligomeric state of OsAOS1 depends strongly on the detergents and that the monomer becomes the predominant form in the presence of detergent micelles. These data suggest that the detergent-dependent oligomeric state of OsAOS1 is an important factor for the regulation of its catalytic efficiency.

  19. Submicrometer Emitter ESI Tips for Native Mass Spectrometry of Membrane Proteins in Ionic and Nonionic Detergents

    NASA Astrophysics Data System (ADS)

    Susa, Anna C.; Lippens, Jennifer L.; Xia, Zijie; Loo, Joseph A.; Campuzano, Iain D. G.; Williams, Evan R.

    2018-01-01

    Native mass spectrometry (native-MS) of membrane proteins typically requires a detergent screening protocol, protein solubilization in the preferred detergent, followed by protein liberation from the micelle by collisional activation. Here, submicrometer nano-ESI emitter tips are used for native-MS of membrane proteins solubilized in both nonionic and ionic detergent solutions. With the submicrometer nano-ESI emitter tips, resolved charge-state distributions of membrane protein ions are obtained from a 150 mM NaCl, 25 mM Tris-HCl with 1.1% octyl glucoside solution. The relative abundances of NaCl and detergent cluster ions at high m / z are significantly reduced with the submicrometer emitters compared with larger nano-ESI emitters that are commonly used. This technique is beneficial for significantly decreasing the abundances (by two to three orders of magnitude compared with the larger tip size: 1.6 μm) of detergent cluster ions formed from aqueous ammonium acetate solutions containing detergents that can overlap with the membrane protein ion signal. Resolved charge-state distributions of membrane protein ions from aqueous ammonium acetate solutions containing ionic detergents were obtained with the submicrometer nano-ESI emitters; this is the first report of native-MS of membrane proteins solubilized by ionic detergents. [Figure not available: see fulltext.

  20. Submicrometer Emitter ESI Tips for Native Mass Spectrometry of Membrane Proteins in Ionic and Nonionic Detergents.

    PubMed

    Susa, Anna C; Lippens, Jennifer L; Xia, Zijie; Loo, Joseph A; Campuzano, Iain D G; Williams, Evan R

    2018-01-01

    Native mass spectrometry (native-MS) of membrane proteins typically requires a detergent screening protocol, protein solubilization in the preferred detergent, followed by protein liberation from the micelle by collisional activation. Here, submicrometer nano-ESI emitter tips are used for native-MS of membrane proteins solubilized in both nonionic and ionic detergent solutions. With the submicrometer nano-ESI emitter tips, resolved charge-state distributions of membrane protein ions are obtained from a 150 mM NaCl, 25 mM Tris-HCl with 1.1% octyl glucoside solution. The relative abundances of NaCl and detergent cluster ions at high m /z are significantly reduced with the submicrometer emitters compared with larger nano-ESI emitters that are commonly used. This technique is beneficial for significantly decreasing the abundances (by two to three orders of magnitude compared with the larger tip size: 1.6 μm) of detergent cluster ions formed from aqueous ammonium acetate solutions containing detergents that can overlap with the membrane protein ion signal. Resolved charge-state distributions of membrane protein ions from aqueous ammonium acetate solutions containing ionic detergents were obtained with the submicrometer nano-ESI emitters; this is the first report of native-MS of membrane proteins solubilized by ionic detergents. Graphical Abstract.

  1. The potential of fluorinated surfactants in membrane biochemistry.

    PubMed

    Shepherd, F H; Holzenburg, A

    1995-01-01

    Detergents are important reagents in membrane biochemistry. Since each membrane system studied places different demands on the detergent in terms of desirous physicochemical properties, detergents new to biochemistry must continuously be sought. Ammonium perfluorooctanoate (APFO) was investigated, as representative of fluorinated surfactants, in terms of its suitability as a "biological detergent." It did not interfere with the Markwell modification of the Lowry procedure at detergent concentrations of up to 2% (w/v). Critical micellization concentration (cmc) values (0.013-0.0275 M) for this detergent were determined in a number of buffers of biological interest. It was demonstrated that the detergent can be removed by dialysis, albeit slowly. This slow removal may be particularly useful for reconstitution/crystallization studies. Solubilization studies on several membrane systems containing the proteins listed (the major protein of the membrane sector of the vacuolar H(+)-ATPase (16 kDa protein); photosystem II; equine herpes virus (EHV) envelope proteins) indicate that it is a potent solubilizing agent, likely to enhance the yield in cases where solubilization has already been demonstrated, and, in other cases, to solubilize proteins formerly recalcitrant to solubilization. The removal of APFO from solubilized 16-kDa protein by means of Extracti-Gel D resin as a means of exchanging detergents quickly and with a minimum requirement for second detergent was investigated.

  2. Opposite behavior of two isozymes when refolding in the presence of non-ionic detergents.

    PubMed Central

    Doñate, F.; Artigues, A.; Iriarte, A.; Martinez-Carrion, M.

    1998-01-01

    GroEL has a greater affinity for the mitochondrial isozyme (mAAT) of aspartate aminotransferase than for its cytosolic counterpart (cAAT) (Mattingly JR Jr, Iriarte A, Martinez-Carrion M, 1995, J Biol Chem 270:1138-1148), two proteins that share a high degree of sequence similarity and an almost identical spatial structure. The effect of detergents on the refolding of these large, dimeric isozymes parallels this difference in behavior. The presence of non-ionic detergents such as Triton X-100 or lubrol at concentrations above their critical micelle concentration (CMC) interferes with reactivation of mAAT unfolded in guanidinium chloride but increases the yield of cAAT refolding at low temperatures. The inhibitory effect of detergents on the reactivation of mAAT decreases progressively as the addition of detergents is delayed after starting the refolding reaction. The rate of disappearance of the species with affinity for binding detergents coincides with the slowest of the two rate-limiting steps detected in the refolding pathway of mAAT. Limited proteolysis studies indicate that the overall structure of the detergent-bound mAAT resembles that of the protein in a complex with GroEL. The mAAT folding intermediates trapped in the presence of detergents can resume reactivation either upon dilution of the detergent below its CMC or by adding beta-cyclodextrin. Thus, isolation of otherwise transient productive folding intermediates for further characterization is possible through the use of detergents. PMID:10082379

  3. Opposite behavior of two isozymes when refolding in the presence of non-ionic detergents.

    PubMed

    Doñate, F; Artigues, A; Iriarte, A; Martinez-Carrion, M

    1998-08-01

    GroEL has a greater affinity for the mitochondrial isozyme (mAAT) of aspartate aminotransferase than for its cytosolic counterpart (cAAT) (Mattingly JR Jr, Iriarte A, Martinez-Carrion M, 1995, J Biol Chem 270:1138-1148), two proteins that share a high degree of sequence similarity and an almost identical spatial structure. The effect of detergents on the refolding of these large, dimeric isozymes parallels this difference in behavior. The presence of non-ionic detergents such as Triton X-100 or lubrol at concentrations above their critical micelle concentration (CMC) interferes with reactivation of mAAT unfolded in guanidinium chloride but increases the yield of cAAT refolding at low temperatures. The inhibitory effect of detergents on the reactivation of mAAT decreases progressively as the addition of detergents is delayed after starting the refolding reaction. The rate of disappearance of the species with affinity for binding detergents coincides with the slowest of the two rate-limiting steps detected in the refolding pathway of mAAT. Limited proteolysis studies indicate that the overall structure of the detergent-bound mAAT resembles that of the protein in a complex with GroEL. The mAAT folding intermediates trapped in the presence of detergents can resume reactivation either upon dilution of the detergent below its CMC or by adding beta-cyclodextrin. Thus, isolation of otherwise transient productive folding intermediates for further characterization is possible through the use of detergents.

  4. Manifestation of cryptic fibroblast tissue factor occurs at detergent concentrations which dissolve the plasma membrane.

    PubMed

    Carson, S D

    1996-04-01

    Cultured fibroblasts treated with increasing concentrations of detergents expressed only encrypted levels of tissue factor activity (measured by fX activation in the presence of fVIIa), characteristic of undamaged cells, until each detergent reached a critical concentration at which the cryptic tissue factor activity was manifested. Beyond the narrow ranges of concentrations over which the detergents stimulated tissue factor activity, the detergents were inhibitory. Studies with Triton X-100 and octyl glucoside revealed that manifestation of tissue factor activity coincided with breakdown of the plasma membrane. The magnitude of the increased tissue factor activity differed among detergents, with octyl glucoside giving the largest response. The tissue factor that was active after Triton X-100 treatment remained mostly associated with the insoluble cell residue, whereas the concentration of octyl glucoside which stimulated activity released tissue factor activity into the supernatant. Radiolabeled antibody against human tissue factor was used to show that a small percentage of the total accessible tissue factor remained in the insoluble fraction after treatment with either non-ionic detergent. Chromatographic analysis of lipids extracted from cells treated with detergents and dansyl chloride showed dansyl-reactivity of phosphatidylserine on intact cells, and solubilization of membrane lipids at sublytic concentrations of detergents. These findings reveal that there is a critical level of detergent-induced membrane damage at which tissue factor activity is maximally expressed, in essentially an all-or-none manner. The results are consistent with a major role for phospholipid asymmetry in regulation of tissue factor specific activity, but require either maintenance of asymmetry during sublytic detergent perturbation of the plasma membrane or additional control mechanisms.

  5. Surveillance of paediatric exposures to liquid laundry detergent pods in Italy

    PubMed Central

    Settimi, Laura; Giordano, Felice; Lauria, Laura; Celentano, Anna; Sesana, Fabrizio; Davanzo, Franca

    2018-01-01

    Objective To analyse paediatric exposures to pod and traditional laundry detergents in Italy and changes in exposure trends. Methods Analyses of a series of patients aged <5 years and exposed to laundry detergents between September 2010 and June 2015, identified by the National Poison Control in Milan. Results In comparison with patients exposed to traditional laundry detergents (n=1150), a higher proportion of those exposed to pods (n=1649) were managed in hospital (68% vs 42%), had clinical effects (75% vs 22%) and moderate/high severity outcomes (13% vs <1%). Exposure rates were stable over time for traditional detergents (average 0.65 cases/day), but an abrupt decline in major company pods was seen in December 2012, 4 months after the introduction of opaque outer packaging (from 1.03 to 0.36 cases/day and from 1.88 to 0.86 cases/million units sold). The odds of clinical effects was higher for exposure to pods than for traditional detergents (OR=10.8; 95% CI 9.0 to 12.9). Among patients exposed to pods, the odds of moderate/high severity outcomes was four times higher for children aged <1 years than for the other age groups (OR=3.9; 95% CI 2.2 to 7.0). Ten children exposed to laundry detergent pods had high severity outcomes while no children exposed to traditional laundry detergents developed high severity effects. Conclusions The study confirms that exposure to laundry detergent pods is more dangerous than exposure to traditional detergents. In Italy, 4 months after the introduction of opaque outer packaging by a major company, product-specific exposure rates decreased sharply, suggesting that reducing visibility of laundry detergent pods may be an effective preventive measure. Further efforts are needed to improve safety. PMID:28188147

  6. Determining the Residual Characteristics of Alkylphenols, Arsenic, and Lead as well as Assessing the Exposures of 1,4-Dioxane from Household Food Detergents.

    PubMed

    Lin, Wan-Ting; Chen, Wun-Ling; Cheng, Wei-Chih; Chang, Hui-Chuan; Tsai, Shih-Wei

    2017-07-01

    Food detergents are commonly used in households. The main components of detergents include surfactants and water. It has been found that certain compounds, which may cause health concerns, appear in food detergents, such as alkylphenols, arsenic, and lead. After applying food detergents is when people may be exposed to various levels of these chemicals when there are residues. In this study, the Taguchi experimental design was performed to determine the possible factors that might affect the residual characteristics of food detergent on dishware, fruits, and vegetables. The results showed that the variety of detergent was found to be the most significant factor affecting the residue amounts of arsenic (62.9%) and lead (71.6%) on fruits and vegetables, whereas the concentration of detergent used affected the amount of lead residue only (10.5%). On the other hand, dishware material, the concentration of analytes, immersion time, and type of surfactant contributed to arsenic residues on dishware, whereas technical nonylphenol isomer residues on dishware increased as the concentration of spiked analyte increased. In addition, the occurrence of 1,4-dioxane, a possible human carcinogen, in household food detergents in Taiwan was also determined in this research by solid-phase microextraction and GC-MS. Among the 80 detergent samples, 71 contained different concentrations ranges of 1,4-dioxane, from 0.03 to ~3.73 µg/g. In the exposure assessment, it was estimated that the maximum amounts of 1,4-dioxane in contact with the skin from the use of household food detergent in Taiwan was 0.015 µg/kg/day.

  7. The solubilisation of boar sperm membranes by different detergents - a microscopic, MALDI-TOF MS, 31P NMR and PAGE study on membrane lysis, extraction efficiency, lipid and protein composition

    PubMed Central

    2009-01-01

    Background Detergents are often used to isolate proteins, lipids as well as "detergent-resistant membrane domains" (DRMs) from cells. Different detergents affect different membrane structures according to their physico-chemical properties. However, the effects of different detergents on membrane lysis of boar spermatozoa and the lipid composition of DRMs prepared from the affected sperm membranes have not been investigated so far. Results Spermatozoa were treated with the selected detergents Pluronic F-127, sodium cholate, CHAPS, Tween 20, Triton X-100 and Brij 96V. Different patterns of membrane disintegration were observed by light and electron microscopy. In accordance with microscopic data, different amounts of lipids and proteins were released from the cells by the different detergents. The biochemical methods to assay the phosphorus and cholesterol contents as well as 31P NMR to determine the phospholipids were not influenced by the presence of detergents since comparable amounts of lipids were detected in the organic extracts from whole cell suspensions after exposure to each detergent. However, matrix-assisted laser desorption and ionization time-of-flight mass spectrometry applied to identify phospholipids was essentially disturbed by the presence of detergents which exerted particular suppression effects on signal intensities. After separation of the membrane fractions released by detergents on a sucrose gradient only Triton X-100 and sodium cholate produced sharp turbid DRM bands. Only membrane solubilisation by Triton X-100 leads to an enrichment of cholesterol, sphingomyelin, phosphatidylinositol and phosphatidylethanolamine in a visible DRM band accompanied by a selective accumulation of proteins. Conclusion The boar sperm membranes are solubilised to a different extent by the used detergents. Particularly, the very unique DRMs isolated after Triton X-100 exposure are interesting candidates for further studies regarding the architecture of sperm. PMID:19906304

  8. [An experimental evaluation of the efficacy of 4 types of detergents for 3 types of dyes to which workers in color-printing plants are exposed].

    PubMed

    Terzaghi, G F; Settimi, L; Peverelli, C; Sevosi, L; Duca, P G

    1996-01-01

    The efficacy of 4 commercial cleansing products was tested with 3 colouring agents widely used in the dyeing industry in a randomised double blind trail involving 8 workers each time. A between-detergents statistically significant difference was observed; the interaction (detergents x colouring agents) was significant. The efficacy of type A detergent was higher for type I-III dyers, while the efficacy of type C detergent, which widely used was lowest.

  9. Screening of detergents for solubilization, purification and crystallization of membrane proteins: a case study on succinate:ubiquinone oxidoreductase from Escherichia coli

    PubMed Central

    Shimizu, Hironari; Nihei, Coh-ichi; Inaoka, Daniel Ken; Mogi, Tatushi; Kita, Kiyoshi; Harada, Shigeharu

    2008-01-01

    Succinate:ubiquinone oxidoreductase (SQR) was solubilized and purified from Escherichia coli inner membranes using several different detergents. The number of phospholipid molecules bound to the SQR molecule varied greatly depending on the detergent combination that was used for the solubilization and purification. Crystallization conditions were screened for SQR that had been solubilized and purified using 2.5%(w/v) sucrose monolaurate and 0.5%(w/v) Lubrol PX, respectively, and two different crystal forms were obtained in the presence of detergent mixtures composed of n-alkyl-oligoethylene glycol monoether and n-alkyl-maltoside. Crystallization took place before detergent phase separation occurred and the type of detergent mixture affected the crystal form. PMID:18765923

  10. Stabilization of photosystem II reaction centers: influence of bile salt detergents and low pH.

    PubMed

    Gall, B; Scheer, H

    1998-07-17

    Rapid deterioration of samples is a major obstacle in research on the isolated reaction center of photosystem II. Its stability was tested systematically using a wide range of detergents, varying pH and temperature. Stability and activity did not depend on ionic properties of detergents or on critical micellar concentration. However, both were significantly increased by bile salt detergents in the dark as well as in the light. Low pH (5.5) and low temperature further improved stability. The results suggest that in particular the zwitterionic bile salt detergent, CHAPS, in pH 5.5 buffers is a very useful detergent and even superior to dodecylmaltoside for work with photosystem II reaction centers.

  11. Screening of detergents for solubilization, purification and crystallization of membrane proteins: a case study on succinate:ubiquinone oxidoreductase from Escherichia coli.

    PubMed

    Shimizu, Hironari; Nihei, Coh-ichi; Inaoka, Daniel Ken; Mogi, Tatushi; Kita, Kiyoshi; Harada, Shigeharu

    2008-09-01

    Succinate:ubiquinone oxidoreductase (SQR) was solubilized and purified from Escherichia coli inner membranes using several different detergents. The number of phospholipid molecules bound to the SQR molecule varied greatly depending on the detergent combination that was used for the solubilization and purification. Crystallization conditions were screened for SQR that had been solubilized and purified using 2.5%(w/v) sucrose monolaurate and 0.5%(w/v) Lubrol PX, respectively, and two different crystal forms were obtained in the presence of detergent mixtures composed of n-alkyl-oligoethylene glycol monoether and n-alkyl-maltoside. Crystallization took place before detergent phase separation occurred and the type of detergent mixture affected the crystal form.

  12. Detergents as selective inhibitors and inactivators of enzymes.

    PubMed

    Vincenzini, M T; Favilli, F; Stio, M; Vanni, P; Treves, C

    1985-01-01

    In order to study the detergent-enzyme interaction and to clarify whether such an interaction produces specific or non-specific effects, we investigated the action of natural and synthetic detergents on enzymatic systems of different levels of complexity (crystalline enzymes, crude homogenates, organ preparations, organisms in toto i.e. rats and germinating seeds). The enzyme-detergent interaction was examined both as a time-independent phenomenon (inhibition) and as a time-dependent phenomenon (inactivation). In in vitro experiments a clear inhibition of pyridine-dependent dehydrogenases by long-chain anionic detergents was found. Cationic detergents have their greatest effect on lipase, LDH, MDH and ICDH from rat liver homogenates. At low concentrations SDS inactivates all the dehydrogenase enzymes studied. With high concentrations (10 mM) of SDS and dodecyltrimethylammonium bromide (C12), there was a sharp and non-specific decrease of enzymatic activities. In the in vivo studies, rats were given detergents to drink; the cationic detergent (C12) was far more effective than SDS with enzymes from both intestine and liver homogenates. SDS and C12 do not seem to interfere with enzyme activities at the beginning of the germination of Pinus pinea and Triticum durum seeds. However a marked reduction of activities does occur at the respective maximum germination times of these seeds. The nonionic detergent is ineffective both as inhibitor and as inactivator.

  13. GDP-GTP exchange processes of G{alpha}i1 protein are accelerated/decelerated depending on the type and the concentration of added detergents.

    PubMed

    Kubota, Makoto; Tanaka, Takeshi; Kohno, Toshiyuki; Wakamatsu, Kaori

    2009-12-01

    Although detergents have been widely used in G-protein studies to increase solubility and stability of the protein, we noticed that detergents modulate the nucleotide-binding properties of G-proteins. Hence, we analysed the effects of detergents on guanine nucleotide exchange reactions of Galpha(i1). Lubrol PX, a non-ionic detergent, which has been widely used in nucleotide dissociation/binding assays, was found to accelerate both GDP dissociation and GTPgammaS binding from/to Galpha in parallel at above its critical micelle concentration (cmc). Sodium cholate, an anionic detergent, which have been used to extract G-proteins from animal tissues, decelerated and accelerated GDP dissociation below and above its cmc, respectively. Surprisingly, micellar cholate decelerated GTPgammaS binding, and the binding rate constant was decreased by three orders of magnitude in the presence of 2% cholate. These results demonstrate that the guanine nucleotide exchange reactions of Galpha(i1) are drastically modulated by detergents differently depending on the type and the state (monomeric or micellar) of the detergents and that dissociation of GDP from Galpha(i1) does not necessarily lead to immediate binding of GTP to Galpha(i1) in some cases. These effects of detergents on G-proteins must be taken into account in G-protein experiments.

  14. Synthesis and Properties of Dodecyl Trehaloside Detergents for Membrane Protein Studies

    PubMed Central

    Tao, Houchao; Fu, Yu; Thompson, Aaron; Lee, Sung Chang; Mahoney, Nicholas; Stevens, Raymond C.; Zhang, Qinghai

    2012-01-01

    Sugar-based detergents, mostly derived from maltose or glucose, prevail in the extraction, solubilization, stabilization and crystallization of membrane proteins. Inspired by the broad use of trehalose for protecting biological macromolecules and lipid bilayer structures, we synthesized new trehaloside detergents for potential applications in membrane protein research. We devised an efficient synthesis of four dodecyl trehalosides, each with the 12-carboned alkyl chain attached to different hydroxyl groups of trehalose, thus presenting a structurally diverse but related family of detergents. The detergent physical properties, including solubility, hydrophobicity, critical micelle concentration (CMC) and size of micelles, were evaluated and compared with the most popular maltoside analog, β- D-dodecylmaltoside (DDM), which varied from each other due to distinct molecular geometries and possible polar group interactions in resulting micelles. Crystals of 2-dodecyl trehaloside (2-DDTre) were also obtained in methanol, and the crystal packing revealed multiple H-bonded interactions among adjacent trehalose groups. The few trehaloside detergents were tested for the solubilization and stabilization of the nociceptin/orphanin FQ peptide receptor (ORL1) and MsbA, which belong to the G-protein coupled receptor (GPCR) and ATP-binding cassette transporter families, respectively. Our results demonstrated the utility of trehaloside detergents as membrane protein solubilization reagents with the optimal detergents being protein dependent. Continuing development and investigations of trehaloside detergents are attractive given their interesting and unique chemical-physical properties and potential interactions with membrane lipids. PMID:22780816

  15. Optimisation of saponin extraction conditions with Camellia sinensis var. assamica seed and its application for a natural detergent.

    PubMed

    Gong, Wanying; Huang, Yewei; Ji, Aibing; Peng, Wenshu; Liu, Cong; Zeng, Yin; Yang, Ruijuan; Yan, Liang; Wang, Xuanjun; Sheng, Jun

    2018-04-01

    Camellia sinensis var. assamica seed cake (a by-product of tea-seed oil) is an abundant resource with poor utilisation. C. sinensis var. assamica seed saponin (CSS) is one kind of non-ionic surfactant. In this study, the CSS extraction conditions were optimised by response surface methodology (RSM) and then the CSS detergent was developed. Additionally, the safety and decontamination ability of the developed detergent were evaluated. The optimised extraction conditions were including the extracting temperature of 40.04 °C, extraction time of 4.97 h, ethanol concentration of 64.11% and liquid-solid ratio of 14.57:1 mL g -1 . The formula of the CSS detergent was as follows: 20% crude CSS, 0.3% oxidised tea polyphenols (OTPs), 0.2% nisin, 0.3% sodium dehydroacetate, 0.7% sodium alginate and 0.5% sodium polyacrylate. The LD 50 of the CSS detergent exceeds 14 g kg -1 in mice, indicating the detergent was non-toxic. Both of the emulsifying and the pesticide residues removal abilities of the CSS detergent were significantly stronger than the commercial detergent. A natural tea seed saponin detergent with good safety and decontamination ability was successfully developed. This can make better use of the tea seed cake, thereby creating added value in the tea seed oil industry. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  16. Biodegradability, toxicity and mutagenicity of detergents: Integrated experimental evaluations.

    PubMed

    Pedrazzani, Roberta; Ceretti, Elisabetta; Zerbini, Ilaria; Casale, Rosario; Gozio, Eleonora; Bertanza, Giorgio; Gelatti, Umberto; Donato, Francesco; Feretti, Donatella

    2012-10-01

    The widespread use of detergents has raised concern with regard to the environmental pollution caused by their active ingredients, which are biorefractory, toxic and persistent. Since detergents are complex mixtures of different substances, in which synergistic effects may occur, we aimed to assess the mutagenicity of different detergent formulations, taking into account aquatic toxicity and ready biodegradability. We performed a ready biodegradability test (OECD 301 F), Daphnia magna and Vibrio fischeri toxicity tests, and mutagenicity tests (Salmonella/microsome test, Allium cepa test and comet assay). Six detergent formulations were examined, 3 pre-manufacture and 3 commercially available. All detergents presented ready biodegradability. EC50 values varied for all products, according to the marker organism used, but were always higher than the more stringent value considered for aquatic toxicity assessment (V. fischeri 10-60 mg/L; D. magna 25-300 mg/L; A. cepa 250-2000 mg/L). None of the detergents caused mutations in bacteria. However, one commercial ecolabelled product induced an increase in micronucleus frequency in A. cepa root cells. All pre-manufacture detergents and one commercial one, which gave negative results in the Ames and A. cepa tests, induced DNA damage in human leukocytes. A more accurate evaluation of the environmental impact of complex mixtures such as detergents requires a battery of tests to describe degradation, as well as toxicological and mutagenic features. Copyright © 2012 Elsevier Inc. All rights reserved.

  17. Characterization of the Protease Activity of Detergents: Laboratory Practicals for Studying the Protease Profile and Activity of Various Commercial Detergents

    ERIC Educational Resources Information Center

    Valls, Cristina; Pujadas, Gerard; Garcia-Vallve, Santi; Mulero, Miquel

    2011-01-01

    Detergent enzymes account for about 30% of the total worldwide production of enzymes and are one of the largest and most successful applications of modern industrial biotechnology. Proteases can improve the wash performance of household, industrial, and institutional laundry detergents used to remove protein-based stains such as blood, grass, body…

  18. Detergents: Friends not foes for high-performance membrane proteomics toward precision medicine.

    PubMed

    Zhang, Xi

    2017-02-01

    Precision medicine, particularly therapeutics, emphasizes the atomic-precise, dynamic, and systems visualization of human membrane proteins and their endogenous modifiers. For years, bottom-up proteomics has grappled with removing and avoiding detergents, yet faltered at the therapeutic-pivotal membrane proteins, which have been tackled by classical approaches and are known for decades refractory to single-phase aqueous or organic denaturants. Hydrophobicity and aggregation commonly challenge tissue and cell lysates, biofluids, and enriched samples. Frequently, expected membrane proteins and peptides are not identified by shotgun bottom-up proteomics, let alone robust quantitation. This review argues the cause of this proteomic crisis is not detergents per se, but the choice of detergents. Recently, inclusion of compatible detergents for membrane protein extraction and digestion has revealed stark improvements in both quantitative and structural proteomics. This review analyzes detergent properties behind recent proteomic advances, and proposes that rational use of detergents may reconcile outstanding membrane proteomics dilemmas, enabling ultradeep coverage and minimal artifacts for robust protein and endogenous PTM measurements. The simplicity of detergent tools confers bottom-up membrane proteomics the sophistication toward precision medicine. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Effect of synthetic detergents on the swelling and the ATPase of mitochondria isolated from rat liver.

    PubMed

    WITTER, R F; MINK, W

    1958-01-25

    A study was made of the effects of various types of detergents on the swelling of isolated mitochondria and on mitochondrial ATPases which are activated by Mg or DNP respectively. The rate of swelling was measured in the Beckman spectrophotometer by following the decrease in turbidity of dilute suspensions of these organelles. It was found that non-ionic detergents containing a nonyl phenoxy side chain or anionic detergents caused swelling of the mitochondria and activation of Mg-ATPase. On the other hand, cationic detergents promoted the clumping of mitochondria and did not activate Mg-ATPase. DNP-ATPase was inhibited by all of the detergents tested. It would appear from these observations that the inhibition of DNP-ATPase is not related to a gross change in the morphology of the organelles; in contrast, the activation of Mg-ATPase definitely is correlated with swelling of the isolated mitochondria. These data also suggest that the ionic detergents combine with charged sites on the protein moiety of the lipoprotein in the mitochondrial surface, whereas the non-ionic detergents form inclusion compounds with the lipide moiety, thereby altering the mitochondrial structure and permeability.

  20. Greatly decreased susceptibility of nonmetabolizing cells towards detergents.

    PubMed Central

    Komor, E; Weber, H; Tanner, W

    1979-01-01

    The addition of different detergents to Chlorella cells that had previously accumulated 6-deoxyglucose causes a rapid release of the hexose analogue into the medium. This effect is independent of the nature of the detergent and is observed only when the cells are in an energized state. Thus, in the presence of the uncoupler p-trifluoromethoxycarbonylcyanide phenylhydrazone or of inhibitors such as N-ethylmaleimide, the cells show a greatly reduced susceptibility towards detergents. Similarly, the detergent-induced loss of accumulated alpha-aminoisobutyric acid from Saccharomyces cerevisiae and of potassium from Escherichia coli is also strongly affected by the energy state of the cells. The differential susceptibility of energized and nonenergized cells was observed at all detergent concentrations tested. Measurements of substrate efflux at different concentrations of Triton indicated that only Triton monomers are responsible for the increase in permeability. The absorption of [14C]Triton X-100 by Chlorella and the binding of detergent to the cells were measured in the presence of metabolic inhibitors. Again, nonenergized cells bound a significantly lower amount of Triton X-100. The amphiphilic antibiotic nystatin produced effects on cell permeability similar to those of detergents, whereas toluene, which is apolar, gave opposite results. PMID:377284

  1. Effect of Detergent on Electrical Properties of Squid Axon Membrane

    PubMed Central

    Kishimoto, Uichiro; Adelman, William J.

    1964-01-01

    The effects of detergents on squid giant axon action and resting potentials as well as membrane conductances in the voltage clamp have been studied. Anionic detergents (sodium lauryl sulfate, 0.1 to 1.0 mM; dimethyl benzene sulfonate, 1 to 20 mM, pH 7.6) cause a temporary increase and a later decrease of action potential height and the value of the resting potential. Cationic detergent (cetyl trimethyl ammonium chloride, 6 x 10-5 M or more, pH 7.6) generally brings about immediate and irreversible decreases in the action and resting potentials. Non-ionic detergent (tween 80, 0.1 M, pH 7.6) causes a slight reversible reduction of action potential height without affecting the value of the resting potential. Both anionic and cationic detergents generally decrease the sodium and potassium conductances irreversibly. The effect of non-ionic detergent is to decrease the sodium conductance reversibly, leaving the potassium conductance almost unchanged. PMID:14158665

  2. A robust method to screen detergents for membrane protein stabilization, revisited.

    PubMed

    Champeil, Philippe; Orlowski, Stéphane; Babin, Simon; Lund, Sten; le Maire, Marc; Møller, Jesper; Lenoir, Guillaume; Montigny, Cédric

    2016-10-15

    This report is a follow up of our previous paper (Lund, Orlowski, de Foresta, Champeil, le Maire and Møller (1989), J Biol Chem 264:4907-4915) showing that solubilization in detergent of a membrane protein may interfere with its long-term stability, and proposing a protocol to reveal the kinetics of such irreversible inactivation. We here clarify the fact that when various detergents are tested for their effects, special attention has of course to be paid to their critical micelle concentration. We also investigate the effects of a few more detergents, some of which have been recently advertised in the literature, and emphasize the role of lipids together with detergents. Among these detergents, lauryl maltose neopentyl glycol (LMNG) exerts a remarkable ability, even higher than that of β-dodecylmaltoside (DDM), to protect our test enzyme, the paradigmatic P-type ATPase SERCA1a from sarcoplasmic reticulum. Performing such experiments for one's favourite protein probably remains useful in pre-screening assays testing various detergents. Copyright © 2016 Elsevier Inc. All rights reserved.

  3. Effects of household detergent on anaerobic fermentation of kitchen wastewater from food waste disposer.

    PubMed

    Lee, K H; Park, K Y; Khanal, S K; Lee, J W

    2013-01-15

    This study examines the effects of household detergent on anaerobic methane fermentation of wastewater from food waste disposers (FWDs). Anaerobic toxicity assay (ATA) demonstrated that methane production substantially decreased at a higher detergent concentration. The Gompertz three-parameter model fitted well with the ATA results, and both the extent of methane production (M) and methane production rate (R(m)) obtained from the model were strongly affected by the concentration of the detergent. The 50% inhibitory concentration (IC(50)) of the detergent was 603 mg/L based on R(m). Results from fatty acid methyl esters (FAMEs) analysis of microbial culture revealed that deterioration of methane fermentation was attributed to impaired structure of anaerobic microbial membrane due to detergent. This study suggests that wastewater from FWD could be used for methane production, but it is necessary to reduce the concentration of detergent prior to anaerobic fermentation. Copyright © 2012 Elsevier B.V. All rights reserved.

  4. Removal of detergents from proteins and peptides in a spin-column format.

    PubMed

    Antharavally, Babu S

    2012-08-01

    To enable downstream analysis, it is critical to remove unbound detergents from protein and peptide samples. This unit describes the use of a high-performance resin that offers exceptional detergent removal for proteins and peptides. The easy-to-use spin format significantly improves results over the standard drip column and batch methodologies, with >95% removal of 1% to 5% detergents, including SDS, sodium deoxycholate, CHAPS, Triton X-100, Triton X-114, NP-40, Brij-35, octyl glucoside, octyl thioglucoside, and lauryl maltoside, with high recovery of proteins and peptides. Detergent removal efficiency is evaluated using colorimetric methods and mass spectrometry (MS). BSA tryptic peptides have been successfully analyzed by liquid chromatography-tandem mass spectrometry (LC-MS/MS) and matrix-assisted laser desorption/ionization (MALDI)-MS for identification of protein, following detergent removal using the resin. Advantages of this method include speed (less than 15 min), efficient detergent removal, and high recovery of proteins and peptides. © 2012 by John Wiley & Sons, Inc.

  5. Respiratory symptoms and pulmonary function impairment among detergent plant workers in Jos, Northern Nigeria.

    PubMed

    Babashani, M; Iliyasu, Z; Ukoli, C O

    2008-01-01

    The industrial process of detergent production could be deleterious to lung function. This study describes respiratory symptoms and ventilatory function impairment among detergent workers in Jos, Northern Nigeria. Two hundred detergent plant workers and controls were studied for the presence of respiratory symptoms and ventilatory function impairment using the MRC questionnaire and Spirometry. A significantly higher proportion of exposed detergent workers 178 (87.0%) reported respiratory symptoms compared to 52 (26.0%) controls [OR=23; 95% CI=12.9-41.3] (P<0.001). Commonest symptoms include rhinitis (57.5% versus 11.0%) and cough (48.5% versus 15%). Symptoms were most prevalent in the packaging section. FEV1, FVC and PEFR were significantly reduced among exposed detergent workers. Similarly, the predicted values of PEFR, FVC and FEV1, were significantly reduced among smokers (P<0. 001). Respiratory symptoms are highly prevalent among detergent workers. This was associated with impaired pulmonary function. Protective equipment and periodic lung function tests could reduce these effects.

  6. Improved detergent-based recovery of polyhydroxyalkanoates (PHAs).

    PubMed

    Yang, Yung-Hun; Brigham, Christopher; Willis, Laura; Rha, ChoKyun; Sinskey, Anthony

    2011-05-01

    Extracting polyhydroxyalkanoate (PHA) polymer from bacterial cells often involves harsh conditions, including use of environmentally harmful solvents. We evaluated different detergents under various conditions to extract PHA from Ralstonia eutropha and Escherichia coli cells. Most detergents tested recovered highly pure PHA polymer from cells in amounts that depended on the percentage of polymer present in the cell. Detergents such as linear alkylbenzene sulfonic acid (LAS-99) produced a high yield of high purity polymer, and less detergent was needed compared to the amount of SDS to produce comparable yields. LAS-99 also has the advantage of being biodegradable and environmentally safe. Chemical extraction of PHA with detergents could potentially minimize or eliminate the need to use harsh organic solvents, thus making industrial PHA production a cleaner technology process. © Springer Science+Business Media B.V. 2011

  7. Systematic analysis of protein–detergent complexes applying dynamic light scattering to optimize solutions for crystallization trials

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Meyer, Arne; Dierks, Karsten; XtalConcepts, Marlowring 19, 22525 Hamburg

    Application of in situ dynamic light scattering to solutions of protein–detergent complexes permits characterization of these complexes in samples as small as 2 µl in volume. Detergents are widely used for the isolation and solubilization of membrane proteins to support crystallization and structure determination. Detergents are amphiphilic molecules that form micelles once the characteristic critical micelle concentration (CMC) is achieved and can solubilize membrane proteins by the formation of micelles around them. The results are presented of a study of micelle formation observed by in situ dynamic light-scattering (DLS) analyses performed on selected detergent solutions using a newly designed advancedmore » hardware device. DLS was initially applied in situ to detergent samples with a total volume of approximately 2 µl. When measured with DLS, pure detergents show a monodisperse radial distribution in water at concentrations exceeding the CMC. A series of all-transn-alkyl-β-d-maltopyranosides, from n-hexyl to n-tetradecyl, were used in the investigations. The results obtained verify that the application of DLS in situ is capable of distinguishing differences in the hydrodynamic radii of micelles formed by detergents differing in length by only a single CH{sub 2} group in their aliphatic tails. Subsequently, DLS was applied to investigate the distribution of hydrodynamic radii of membrane proteins and selected water-insoluble proteins in presence of detergent micelles. The results confirm that stable protein–detergent complexes were prepared for (i) bacteriorhodopsin and (ii) FetA in complex with a ligand as examples of transmembrane proteins. A fusion of maltose-binding protein and the Duck hepatitis B virus X protein was added to this investigation as an example of a non-membrane-associated protein with low water solubility. The increased solubility of this protein in the presence of detergent could be monitored, as well as the progress of proteolytic cleavage to separate the fusion partners. This study demonstrates the potential of in situ DLS to optimize solutions of protein–detergent complexes for crystallization applications.« less

  8. High-Melting Lipid Mixtures and the Origin of Detergent-Resistant Membranes Studied with Temperature-Solubilization Diagrams

    PubMed Central

    Sot, Jesús; Manni, Marco M.; Viguera, Ana R.; Castañeda, Verónica; Cano, Ainara; Alonso, Cristina; Gil, David; Valle, Mikel; Alonso, Alicia; Goñi, Félix M.

    2014-01-01

    The origin of resistance to detergent solubilization in certain membranes, or membrane components, is not clearly understood. We have studied the solubilization by Triton X-100 of binary mixtures composed of egg sphingomyelin (SM) and either ceramide, diacylglycerol, or cholesterol. Solubilization has been assayed in the 4–50°C range, and the results are summarized in a novel, to our knowledge, form of plots, that we have called temperature-solubilization diagrams. Despite using a large detergent excess (lipid/detergent 1:20 mol ratio) and extended solubilization times (24–48 h) certain mixtures were not amenable to Triton X-100 solubilization at one or more temperatures. DSC of all the lipid mixtures, and of all the lipid + detergent mixtures revealed that detergent resistance was associated with the presence of gel domains at the assay temperature. Once the system melted down, solubilization could occur. In general adding high-melting lipids limited the solubilization, whereas the addition of low-melting lipids promoted it. Lipidomic analysis of Madin-Darby canine kidney cell membranes and of the corresponding detergent-resistant fraction indicated a large enrichment of the nonsolubilized components in saturated diacylglycerol and ceramide. SM-cholesterol mixtures were special in that detergent solubilization was accompanied, for certain temperatures and compositions, by an independent phenomenon of reassembly of the partially solubilized lipid bilayers. The temperature at which lysis and reassembly prevailed was ∼25°C, thus for some SM-cholesterol mixtures solubilization occurred both above and below 25°C, but not at that temperature. These observations can be at the origin of the detergent resistance effects observed with cell membranes, and they also mean that cholesterol-containing detergent-resistant membrane remnants cannot correspond to structures existing in the native membrane before detergent addition. PMID:25517149

  9. [Determination of the detergent efficiency of the detergents disinfecting for surfaces].

    PubMed

    Santucci, R; Kuntzmann, X; Mesli, N; Meunier, O

    2009-01-01

    Since the disinfecting activity of disinfectants is evaluated by standards, the intrinsic detergent activity is not easily quantifiable and no standard have been suggested yet. Beyond the physicochemical parameters like wettability or foaming presented by the manufacturers, it appears necessary to us to objectively measure the real effect of the detergent agent. The objective of our work is to propose a simple, fast and reproducible method to evaluate detersive activity of the disinfecting detergents. We measured three factors (total amount of extracted bacteria, extraction efficiency and slope of extracting curve) by using Rodac prints technique on two different supports (PVC, stainless steel) that have been contaminated by either E. coli or S. aureus. An increasing mark from 1 to 6 is given to each of these factors in case of statistically differences. The three factors allowed us to calculate a "Specific Index of detersion" (SI) for each germ/support couple (3 to 18). Addition of the marks given to each couple for each disinfecting detergent allowed to calculate a "Globally Index of detersion" (GI) (9 to 72). We tested 4 commercialised disinfecting detergents: Surfanios, Aniosurf, Major C100 and Ecodiol. All detergents may be classified according to their effectiveness on a bacterium/support couple (value of the SI). This enlights a specific spectrum for each disinfecting detergents. As a result, Ecodiol seems to be the most effective deterging agent on 3 of the 4 germ/support couples (S. aureus/PVC, E. coli/PVC and E. coli/stainless steel), whereas Aniosurf is most effective on the S. aureus/stainless steel couple. The GI is very useful to choose the best compromise between activities for all situations. GI rankings of the tested agents were as follows: water < Aniosurf < Surfanios < neutralizing < Major C100 < Ecodiol. This experimental model will be used to test and compare the intrinsic detergent activities of other commercialised products which are usually used for the biocleaning of the medical devices (i.e. endoscopes or reusable dialysis device).

  10. Structure formation in binary mixtures of lipids and detergents: self-assembly and vesicle division.

    PubMed

    Noguchi, Hiroshi

    2013-01-14

    Self-assembly dynamics in binary surfactant mixtures and structure changes of lipid vesicles induced by detergent solution are studied using coarse-grained molecular simulations. Disk-shaped micelles, the bicelles, are stabilized by detergents surrounding the rim of a bilayer disk of lipids. The self-assembled bicelles are considerably smaller than bicelles formed from vesicle rupture, and their size is determined by the concentrations of lipids and detergents and the interactions between the two species. The detergent-adsorption induces spontaneous curvature of the vesicle bilayer and results in vesicle division into two vesicles or vesicle rupture into worm-like micelles. The division occurs mainly via the inverse pathway of the modified stalk model. For large spontaneous curvature of the monolayers of the detergents, a pore is often opened, thereby leading to vesicle division or worm-like micelle formation.

  11. The variable detergent sensitivity of proteases that are utilized for recombinant protein affinity tag removal

    PubMed Central

    Vergis, James M.; Wiener, Michael C.

    2011-01-01

    Recombinant proteins typically include one or more affinity tags to facilitate purification and/or detection. Expression constructs with affinity tags often include an engineered protease site for tag removal. Like other enzymes, the activities of proteases can be affected by buffer conditions. The buffers used for integral membrane proteins contain detergents, which are required to maintain protein solubility. We examined the detergent sensitivity of six commonly-used proteases (Enterokinase, Factor Xa, Human Rhinovirus 3C Protease, SUMOstar, Tobacco Etch Virus Protease, and Thrombin) by use of a panel of ninety-four individual detergents. Thrombin activity was insensitive to the entire panel of detergents, thus suggesting it as the optimal choice for use with membrane proteins. Enterokinase and Factor Xa were only affected by a small number of detergents, making them good choices as well. PMID:21539919

  12. A new high-performance thin layer chromatography-based assay of detergents and surfactants commonly used in membrane protein studies.

    PubMed

    Barret, Laurie-Anne; Polidori, Ange; Bonneté, Françoise; Bernard-Savary, Pierre; Jungas, Colette

    2013-03-15

    The hydrophobic nature of membrane proteins (MPs) necessitates the use of detergents for their extraction, solubilization and purification. Because the concentration of amphiphiles is crucial in the crystallization process, detergent quantification is essential to routine analysis. Here we describe a quantitative high-performance thin-layer chromatography (HPTLC) method we developed for the detection of small quantities of detergent bound to solubilized MPs. After optimization of aqueous deposit conditions, we show that most detergents widely used in membrane protein crystallography display distinctive mobilities in a mixture of dichloromethane, methanol and acetic acid 32:7.6:0.4 (v/v/v). Migration and derivatization conditions were optimized with n-dodecyl-β-D-maltoside (DDM), the most popular detergent for membrane protein crystallization. A linear calibration curve very well fits our data from 0.1 to 1.6 μg of DDM in water with a limit of detection of 0.05 μg. This limit of detection is the best achieved to date for a routine detergent assay, being not modified by the addition of NaCl, commonly used in protein buffers. With these chromatographic conditions, no prior treatment is required to assess the quantities of detergent bound to purified MPs, thus enabling the quantification of close structure detergents via a single procedure. This HPTLC method, which is fast and requires low sample volume, is fully suitable for routine measurements. Copyright © 2013 Elsevier B.V. All rights reserved.

  13. Concentrating membrane proteins using ultrafiltration without concentrating detergents.

    PubMed

    Feroz, Hasin; Vandervelden, Craig; Ikwuagwu, Bon; Ferlez, Bryan; Baker, Carol S; Lugar, Daniel J; Grzelakowski, Mariusz; Golbeck, John H; Zydney, Andrew L; Kumar, Manish

    2016-10-01

    Membrane proteins (MPs) are of rapidly growing interest in the design of pharmaceutical products, novel sensors, and synthetic membranes. Ultrafiltration (UF) using commercially available centrifugal concentrators is typically employed for laboratory-scale concentration of low-yield MPs, but its use is accompanied by a concomitant increase in concentration of detergent micelles. We present a detailed analysis of the hydrodynamic processes that control detergent passage during ultrafiltration of MPs and propose methods to optimize detergent passage during protein concentration in larger-scale membrane processes. Experiments were conducted using nonionic detergents, octyl-β-D glucoside (OG), and decyl-β-D maltoside (DM) with the bacterial water channel protein, Aquaporin Z (AqpZ) and the light driven chloride pump, halorhodopsin (HR), respectively. The observed sieving coefficient (So ), a measure of detergent passage, was evaluated in both stirred cell and centrifugal systems. So for DM and OG increased with increasing filtrate flux and decreasing shear rates in the stirred cell, that is, with increasing concentration polarization (CP). Similar effects were observed during filtration of MP-detergent (MPD) micelles. However, lower transmission was observed in the centrifugal system for both detergent and MPD systems. This is attributed to free convection-induced shear and hence reduced CP along the membrane surface during centrifugal UF. Thus to concentrate MPs without retention of detergent, design of UF systems that promote CP is required. Biotechnol. Bioeng. 2016;113: 2122-2130. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  14. Acetylcholinesterase from Apis mellifera head. Evidence for amphiphilic and hydrophilic forms characterized by Triton X-114 phase separation.

    PubMed Central

    Belzunces, L P; Toutant, J P; Bounias, M

    1988-01-01

    The polymorphism of bee acetylcholinesterase was studied by sucrose-gradient-sedimentation analysis and non-denaturing electrophoretic analysis of fresh extracts. Lubrol-containing extracts exhibited only one form, which sedimented at 5 S when analysed on high-salt Lubrol-containing gradients and 6 S when analysed on low-salt Lubrol-containing gradients. The 5 S/6 S form aggregated upon removal of the detergent when sedimented on detergent-free gradients and was recovered in the detergent phase after Triton X-114 phase separation. Thus the 5 S/6 S enzyme corresponds to an amphiphilic acetylcholinesterase form. In detergent-free extracts three forms, whose apparent sedimentation coefficients are 14 S, 11 S and 7 S, were observed when sedimentations were performed on detergent-free gradients. Sedimentation analyses on detergent-containing gradients showed only a 5 S peak in high-salt detergent-free extracts and a 6 S peak, with a shoulder at about 7 S, in low-salt detergent-free extracts. Electrophoretic analysis in the presence of detergent demonstrated that the 14 S and 11 S peaks corresponded to aggregates of the 5 S/6 S form, whereas the 7 S peak corresponded to a hydrophilic acetylcholinesterase form which was recovered in the aqueous phase following Triton X-114 phase separation. The 5 S/6 S amphiphilic form could be converted into a 7.1 S hydrophilic form by phosphatidylinositol-specific phospholipase C digestion. Images Fig. 3. Fig. 6. PMID:2849414

  15. Effects of Lipid-Analog Detergent Solubilization on the Functionality and Lipidic Cubic Phase Mobility of the Torpedo californica Nicotinic Acetylcholine Receptor

    PubMed Central

    Padilla-Morales, Luis F.; Morales-Pérez, Claudio L.; De La Cruz-Rivera, Pamela C.; Asmar-Rovira, Guillermo; Báez-Pagán, Carlos A.

    2011-01-01

    Over the past three decades, the Torpedo californica nicotinic acetylcholine receptor (nAChR) has been one of the most extensively studied membrane protein systems. However, the effects of detergent solubilization on nAChR stability and function are poorly understood. The use of lipid-analog detergents for nAChR solubilization has been shown to preserve receptor stability and functionality. The present study used lipid-analog detergents from phospholipid-analog and cholesterol-analog detergent families for solubilization and affinity purification of the receptor and probed nAChR ion channel function using planar lipid bilayers (PLBs) and stability using analytical size exclusion chromatography (A-SEC) in the detergent-solubilized state. We also examined receptor mobility on the lipidic cubic phase (LCP) by measuring the nAChR mobile fraction and diffusion coefficient through fluorescence recovery after photobleaching (FRAP) experiments using lipid-analog and non-lipid-analog detergents. Our results show that it is possible to isolate stable and functional nAChRs using lipid-analog detergents, with characteristic ion channel currents in PLBs and minimal aggregation as observed in A-SEC. Furthermore, fractional mobility and diffusion coefficient values observed in FRAP experiments were similar to the values observed for these parameters in the recently LCP-crystallized β2-adrenergic receptor. The overall results show that phospholipid-analog detergents with 16 carbon acyl-chains support nAChR stability, functionality and LCP mobility. PMID:21922299

  16. Ligand-induced association of surface immunoglobulin with the detergent insoluble cytoskeleton may involve an 89K protein

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gupta, S.K.; Woda, B.

    1986-03-01

    Membrane immunoglobulin of B-lymphocytes is thought to play an important role in antigen recognition and cellular activation. Binding of cross-linking ligands to surface immunoglobulin (SIg) on intact cells converts it to a detergent insoluble state, and this conversion is associated with the transmission of a mitogenic signal. Insolubilized membrane proteins may be solubilized by incubating the detergent insoluble cytoskeletons in buffers which convert F-actin to G-actin ((Buffer 1), 0.34M sucrose, 0.5mM ATP, 0.5mM Dithiothrietol and lmM EDTA). Immunoprecipitation of SIg from the detergent soluble fraction of /sup 35/S-methionine labeled non ligand treated rat B-cells results in the co-isolation of anmore » 89K protein and a 44K protein, presumably actin. The 89K protein is not associated with the fraction of endogenous detergent insoluble SIg. On treatment of rat B cells with cross-linking ligand (anti-Ig) the 89K protein becomes detergent insoluble along with most of the SIg and co-isolates with SIg on immunoprecipitation of the detergent insoluble, buffer l solubilized fraction. The migration of the SIg-associated 89K protein from the detergent soluble fraction to the detergent insoluble fraction after ligand treatment, suggests that this protein might be involved in linking SIg to the underlying cytoskeleton and could be involved in the transmission of a mitogenic signal.« less

  17. Characterization of the Activity and Stability of Amylase from Saliva and Detergent: Laboratory Practicals for Studying the Activity and Stability of Amylase from Saliva and Various Commercial Detergents

    ERIC Educational Resources Information Center

    Valls, Cristina; Rojas, Cristina; Pujadas, Gerard; Garcia-Vallve, Santi; Mulero, Miquel

    2012-01-01

    This article presents two integrated laboratory exercises intended to show students the role of [alpha]-amylases (AAMYs) in saliva and detergents. These laboratory practicals are based on the determination of the enzymatic activity of amylase from saliva and different detergents using the Phadebas test (quantitative) and the Lugol test…

  18. All-atom molecular dynamics simulation of a photosystem i/detergent complex.

    PubMed

    Harris, Bradley J; Cheng, Xiaolin; Frymier, Paul

    2014-10-09

    All-atom molecular dynamics (MD) simulation was used to investigate the solution structure and dynamics of the photosynthetic pigment-protein complex photosystem I (PSI) from Thermosynechococcus elongatus embedded in a toroidal belt of n-dodecyl-β-d-maltoside (DDM) detergent. Evaluation of root-mean-square deviations (RMSDs) relative to the known crystal structure show that the protein complex surrounded by DDM molecules is stable during the 200 ns simulation time, and root-mean-square fluctuation (RMSF) analysis indicates that regions of high local mobility correspond to solvent-exposed regions such as turns in the transmembrane α-helices and flexible loops on the stromal and lumenal faces. Comparing the protein-detergent complex to a pure detergent micelle, the detergent surrounding the PSI trimer is found to be less densely packed but with more ordered detergent tails, contrary to what is seen in most lipid bilayer models. We also investigated any functional implications for the observed conformational dynamics and protein-detergent interactions, discovering interesting structural changes in the psaL subunits associated with maintaining the trimeric structure of the protein. Importantly, we find that the docking of soluble electron mediators such as cytochrome c6 and ferredoxin to PSI is not significantly impacted by the solubilization of PSI in detergent.

  19. Detergent Disposal into Our Environmentand Its Impact on Marine Microbes

    NASA Astrophysics Data System (ADS)

    Effendi, I.; Nedi, S.; Ellizal; Nursyirwani; Feliatra; Fikar; Tanjung; Pakpahan, R.; Pratama

    2017-12-01

    Detergents figure in an extensive array of industrial and home cleaning applications, released into the flow of wastewater coming from the home, can far-reaching environmental impacts. Microorganisms are crucial to nutrient recycling in ecosystems as they act as decomposers, pathogen, antibiotic producer, biodegradation of pollutants etc. The research is aimed to examine effect detergent disposal to bacterial population growth in marine environment both in vitro and in situ condition. Seawater samples were collected from Sungai Kayu Ara Village, and Dumai River estuary, Siak Regency and Dumai City, Riau Province. Experimental method with complete randomized design (RAL) 2 (two) factors; a detergent brand (a1: ATTACK, a2; RINSO and a3; SURF) and b concentration of detergent concentration with 5 (five) concentration level, b1 (0%) as control, b2 (0.3%), b3 (0.6%), b4 (0.9%) and b5 (1.2%) wass applied. The study showed that there was an effect of detergent addition, periode of exposure, and doses to the growth of bacterial population both in vitro and in situ conditions. The higher levels of detergent in the water column and the longer contamination duration, causing more and more depressed bacterial populations. It is suggested to run a further research on identification, and growth optimatioan of the species capable of degrading detergent.

  20. All-atom molecular dynamics simulation of a photosystem I/detergent complex

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Harris, Bradley J.; Cheng, Xiaolin; Frymier, Paul

    2014-09-18

    All-atom molecular dynamics (MD) simulation was used to investigate the solution structure and dynamics of the photosynthetic pigment protein complex photosystem I (PSI) from Thermosynechococcus elongatus embedded in a toroidal belt of n-dodecyl-β-d-maltoside (DDM) detergent. Evaluation of root-mean-square deviations (RMSDs) relative to the known crystal structure show that the protein complex surrounded by DDM molecules is stable during the 200 ns simulation time, and root-mean-square fluctuation (RMSF) analysis indicates that regions of high local mobility correspond to solvent-exposed regions such as turns in the transmembrane α-helices and flexible loops on the stromal and lumenal faces. Comparing the protein detergent complexmore » to a pure detergent micelle, the detergent surrounding the PSI trimer is found to be less densely packed but with more ordered detergent tails, contrary to what is seen in most lipid bilayer models. We also investigated any functional implications for the observed conformational dynamics and protein detergent interactions, discovering interesting structural changes in the psaL subunits associated with maintaining the trimeric structure of the protein. Moreover, we find that the docking of soluble electron mediators such as cytochrome c 6 and ferredoxin to PSI is not significantly impacted by the solubilization of PSI in detergent.« less

  1. Ecotoxicity evaluation of a liquid detergent using the automatic biotest ECOTOX.

    PubMed

    Azizullah, Azizullah; Richter, Peter; Ullah, Waheed; Ali, Imran; Häder, Donat-Peter

    2013-08-01

    Synthetic detergents are common pollutants reaching aquatic environments in different ways after usage at homes, institutions and industries. In this study a liquid detergent, used for dish washing, was evaluated for its toxicity during long- and short-term tests using the automatic biotest ECOTOX. Different parameters of Euglena gracilis like motility, swimming velocity, gravitactic orientation, cell compactness and cell growth were used as end points. In short-term experiments, the maximum adverse effects on motility, velocity, cell shape and gravitaxis were observed after 1 h of exposure. With further increase in exposure time to the detergent a slight recovery of these parameters was observed. In long-term experiments, the detergent caused severe disturbances to E. gracilis. Motility, cell growth and cell compactness (shape) with EC50 values of 0.064, 0.18 and 2.05 %, respectively, were found as the most sensitive parameters to detergent stress. There was a slight positive effect on gravitactic orientation at the lowest two concentrations; at higher concentrations of the detergent cells orientation was highly impaired giving EC50 values of 1.75 and 2.52 % for upward swimming and r-value, respectively.

  2. Isomeric Detergent Comparison for Membrane Protein Stability: Importance of Inter-Alkyl-Chain Distance and Alkyl Chain Length

    PubMed Central

    Cho, Kyung Ho; Hariharan, Parameswaran; Mortensen, Jonas S.; Du, Yang; Nielsen, Anne K.; Byrne, Bernadette; Kobilka, Brian K.; Loland, Claus J.; Guan, Lan

    2017-01-01

    Membrane proteins encapsulated by detergent micelles are widely used for structural study. Because of their amphipathic property, detergents have the ability to maintain protein solubility and stability in an aqueous medium. However, conventional detergents have serious limitations in their scope and utility, particularly for eukaryotic membrane proteins and membrane protein complexes. Thus, a number of new agents have been devised; some have made significant contributions to membrane protein structural studies. However, few detergent design principles are available. In this study, we prepared meta and ortho isomers of the previously reported para-substituted xylene-linked maltoside amphiphiles (XMAs), along with alkyl chain-length variation. The isomeric XMAs were assessed with three membrane proteins, and the meta isomer with a C12 alkyl chain was most effective at maintaining solubility/stability of the membrane proteins. We propose that interplay between the hydrophile–lipophile balance (HLB) and alkyl chain length is of central importance for high detergent efficacy. In addition, differences in inter-alkyl-chain distance between the isomers influence the ability of the detergents to stabilise membrane proteins. PMID:27981750

  3. Detection and quantification of anionic detergent (lissapol) in milk using attenuated total reflectance-Fourier Transform Infrared spectroscopy.

    PubMed

    Jaiswal, Pranita; Jha, Shyam Narayan; Kaur, Jaspreet; Borah, Anjan

    2017-04-15

    Adulteration of milk to gain economic benefit is rampant. Addition of detergent in milk can cause food poisoning and other complications. Fourier Transform Infrared spectroscopy was evaluated as rapid method for detection and quantification of anionic detergent (lissapol) in milk. Spectra of pure and artificially adulterated milk (0.2-2.0% detergent) samples revealed clear differences in wavenumber range of 4000-500cm -1 . The apparent variations observed in region of 1600-995 and 3040-2851cm -1 corresponds to absorption frequencies of common constituents of detergent (linear alkyl benzene sulphonate). Principal component analysis showed discrete clustering of samples based on level of detergent (p⩽0.05) in milk. The classification efficiency for test samples were recorded to be >93% using Soft Independent Modelling of Class Analogy approach. Maximum coefficient of determination for prediction of detergent was 0.94 for calibration and 0.93 for validation, using partial least square regression in wavenumber combination of 1086-1056, 1343-1333, 1507-1456, 3040-2851cm -1 . Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Dry Skin

    MedlinePlus

    ... bars such as Neutrogena ® ) instead of harsh true “soaps.” Detergents are not the same as soap and are not necessarily bad; in fact, most bath bars are detergents and not soaps. Often, detergents are able to control the acid/ ...

  5. The Effect Of Additional Detergent In Crude Palm Oil In The Process Of Separation Stearin

    NASA Astrophysics Data System (ADS)

    Rezekyah Hasibuan, Vina; aini, Nur; Febriyanti; Ayubi Pane, Salahudin Al

    2018-03-01

    This study aims to find out how much stearin is formed from the addition of detergent and to understand the process of separation of crude olein with crude stearin from raw material of crude palm oil (CPO). Using a detergent fractionation system, detergent fractionation is a continuous crystallization of oil with controlled cooling and the separation of fractions by weight or centrifuge after supplementing surfactant.

  6. Comparative studies on ecotoxicology of synthetic detergents.

    PubMed

    Lal, H; Misra, V; Viswanathan, P N; Krishna Murti, C R

    1983-12-01

    To predict the comparative toxicological response of synthetic detergents on aquatic ecosystems, the effects of various concentrations of neutralized alkyl benzene sulfonate were studied. The median tolerance limit at 48 hr, 95% confidence limit, slope function, presumable harmless concentration, and rate of survival of different species of aquatic fauna such as water fleas (Daphnia magna), mosquito larvae (Culex pipiens), slug worms (Tubifex rivulorum), snails (Lymnaea vulgaris), tadpoles (Rana cyanophlyctis), and fish fingerlings (Cirrhina mrigala) were followed at 0, 24, 48, 72, and 96 hr. Any effect on quality of the water was also tested after the addition of various concentrations of detergents. The results showed that water fleas are more susceptible to detergent toxicity than fish fingerlings, tadpoles, slug worms, snails, and mosquito larvae. Behavioral changes were also observed as an index for detergent toxicity. The relative toxicity of the detergents to various species is discussed in relation to selective ecotoxicological response.

  7. Chronic toxicity of a laundry detergent to the freshwater flagellate Euglena gracilis.

    PubMed

    Azizullah, Azizullah; Richter, Peter; Jamil, Muhammad; Häder, Donat-Peter

    2012-10-01

    Chronic toxicity of the common laundry detergent Ariel on the freshwater alga Euglena gracilis was investigated by growing the alga in a medium containing the detergent for 7 days. Cell density, motility, swimming velocity, gravitactic orientation, cell shape, photosynthesis and concentration of light-harvesting pigments were used as end point parameters for the assessment of toxicity. Cell density was significantly reduced at a concentration of 1 mg l(-1) or above. Among the other tested parameters, with the exception of cell shape, gravitaxis and chlorophyll b, all were adversely affected by the detergent at concentrations exceeding 1 mg l(-1). It is concluded that long-term (7-days) exposure to the detergent caused significant toxicity to E. gracilis. Furthermore, long-term tests with E. gracilis can be used as sensitive indicator for the toxicity assessment of laundry detergents in aquatic environments.

  8. Efficacy of Detergent and Water Versus Bleach for the Disinfection of Direct Contact Ophthalmic Lenses

    PubMed Central

    Abbey, Ashkan M.; Gregori, Ninel Z.; Surapaneni, Krishna; Miller, Darlene

    2014-01-01

    Purpose While manufacturers recommend cleaning ophthalmic lenses with detergent and water and then a specific disinfectant, disinfectants are rarely used in ophthalmic practices. The aim of this pilot study was to evaluate the efficacy of detergent and water versus bleach, a recommended disinfectant, to eliminate common ocular bacteria and viruses from ophthalmic lenses. Methods Three bacterial strains (Staphylococcus epidermidis, Corynebacterium straitum, and methicillin-resistant Staphylococcus aureus (MRSA) and two viral strains (adenovirus and herpes simplex virus (HSV) type-1) were individually inoculated to 20 gonioscopy and laser lenses. Lenses were washed with detergent and water and then disinfected with 10% bleach. All lenses were cultured after inoculation, after detergent and water, and after the bleach. Bacterial cultures in thioglycollate broth were observed for 3 weeks and viral cultures for 2 weeks. The presence of viruses was also detected by multiplex polymerase chain reaction (PCR). Results All 20 lenses inoculated with Staphylococcus epidermidis, Corynebacterium straitum, adenovirus, and HSV-1 showed growth after inoculation, but no growth after detergent/water and after the bleach. All lenses showed positive HSV and adenovirus PCR after inoculation and negative PCR after detergent/water and after bleach. All MRSA contaminated lenses showed growth after inoculation and no growth after detergent and water. However, one lens showed positive growth after bleach. Conclusions Cleaning with detergent and water appeared to effectively eliminate bacteria and viruses from the surface of contaminated ophthalmic lenses. Further studies are warranted to design practical disinfection protocols that minimize lens damage. PMID:24747806

  9. Self-Assembling Peptide Detergents Stabilize Isolated Photosystem Ion a Dry Surface for an Extended Time

    PubMed Central

    Kiley, Patrick; Zhao, Xiaojun; Vaughn, Michael; Baldo, Marc A; Bruce, Barry D

    2005-01-01

    We used a class of designed peptide detergents to stabilize photosystem I (PS-I) upon extended drying under N2 on a gold-coated-Ni-NTA glass surface. PS-I is a chlorophyll-containing membrane protein complex that is the primary reducer of ferredoxin and the electron acceptor of plastocyanin. We isolated the complex from the thylakoids of spinach chloroplasts using a chemical detergent. The chlorophyll molecules associated with the PS-I complex provide an intrinsic steady-state emission spectrum between 650 and 800 nm at −196.15 °C that reflects the organization of the pigment-protein interactions. In the absence of detergents, a large blue shift of the fluorescence maxima from approximately 735 nm to approximately 685 nm indicates a disruption in light-harvesting subunit organization, thus revealing chlorophyll−protein interactions. The commonly used membrane protein-stabilizing detergents, N-dodecyl-β-D-maltoside and N-octyl-β-D-glucoside, only partially stabilized the approximately 735-nm complex with approximately 685-nm spectroscopic shift. However, prior to drying, addition of the peptide detergent acetyl- AAAAAAK at increasing concentration significantly stabilized the PS-I complex. Moreover, in the presence of acetyl- AAAAAAK, the PS-I complex is stable in a dried form at room temperature for at least 3 wk. Another peptide detergent, acetyl-VVVVVVD, also stabilized the complex but to a lesser extent. These observations suggest that the peptide detergents may effectively stabilize membrane proteins in the solid-state. These designed peptide detergents may facilitate the study of diverse types of membrane proteins. PMID:15954800

  10. Characterization of the protease activity of detergents: laboratory practicals for studying the protease profile and activity of various commercial detergents.

    PubMed

    Valls, Cristina; Pujadas, Gerard; Garcia-Vallve, Santi; Mulero, Miquel

    2011-07-01

    Detergent enzymes account for about 30% of the total worldwide production of enzymes and are one of the largest and most successful applications of modern industrial biotechnology. Proteases can improve the wash performance of household, industrial, and institutional laundry detergents used to remove protein-based stains such as blood, grass, body fluids, and food soils. This article describes two easy and cheap laboratory exercises to study the presence, profile, and basic enzymology of detergent proteases. These laboratory practicals are based on the determination of the detergent protease activity of various commercial detergents using the N-succinyl-L-alanyl-L-alanyl-L-prolyl-L-phenylalanine p-nitroanilide method and the bovine serum albumin degradation capacity. Students are also required to elucidate the enzymatic subtype of detergent proteases by studying the inhibitory potential of several types of protease inhibitors revealed by the same experimental methodology. Additionally, the results of the exercises can be used to provide additional insights on elementary enzymology by studying the influence of several important parameters on protease activity such as temperature (in this article) and the influence of pH and effects of surfactants and oxidizers (proposed). Students also develop laboratory skills, problem-solving capacities, and the ability to write a laboratory report. The exercises are mainly designed for an advanced undergraduate project in the biochemistry and biotechnology sciences. Globally, these laboratory practicals show students the biotechnological applications of proteases in the detergent industry and also reinforce important enzymology concepts. Copyright © 2010 Wiley Periodicals, Inc.

  11. Determination and residual characteristic of alkylphenols in household food detergents of Taiwan.

    PubMed

    Pan, Yi-Ping; Tsai, Shih-Wei

    2009-07-01

    The non-ionic surfactants are mostly composed of alkylphenols for the ingredients of synthetic food detergents. Due to the ability to mimic hormones, it has been noticed that the exposures of alkylphenols might cause a variety of adverse effects. To assess the associate risks from possible exposures, concentrations of alkylphenols, including 4-nonylphenol (4-NP), technical nonylphenol isomers (t-NP(S)), and 4-tert-octylphenol (4-t-OP), in household food detergents of Taiwan were determined. Gas chromatography with mass spectrometer (GC/MS) was used to analyze alkylphenols in samples. The Taguchi experimental design was utilized to study the possible factors that might affect the residual characteristics of alkylphenols from detergents on dishware and fruits. By the analysis of variance, the orders of importance of different parameters were determined. The results showed that the concentrations of alkylphenols in food detergents ranged from 1.71 x 10(-5) to 2.13 x 10(-3) (APs/detergent, mgg(-1)). For residual characteristics, the cleaning temperature was found to be the only significant factor that will affect the 4-t-OP left on the dishware, while the concentrations of detergents used will affect the left of t-NPs and 4-NP on dishware as well. On the other hand, the varieties of fruits, the concentrations of detergents, and the concentrations of alkylphenols were found to have significant effects for the t-NPs left on fruits. As for the exposure assessments, the maximum dose of APs exposures from the use of household food detergents in Taiwan was also estimated in the study.

  12. Soaps and Detergents--A 'Social' Treatment.

    ERIC Educational Resources Information Center

    Rust, S. C.

    1979-01-01

    Describes how social aspects of science can be incorporated into teaching soap and detergents in British secondary chemistry and general science courses. Historical background to the use and production of soap and the development of detergents are also presented. (HM)

  13. Detergent-Specific Membrane Protein Crystallization Screens

    NASA Technical Reports Server (NTRS)

    Wiener, Michael

    2007-01-01

    A suite of reagents has been developed for three-dimensional crystallization of integral membranes present in solution as protein-detergent complexes (PDCs). The compositions of these reagents have been determined in part by proximity to the phase boundaries (lower consolute boundaries) of the detergents present in the PDCs. The acquisition of some of the requisite phase-boundary data and the preliminary design of several of the detergent- specific screens was supported by a NASA contract. At the time of expiration of the contract, a partial set of preliminary screens had been developed. This work has since been extended under non-NASA sponsorship, leading to near completion of a set of 20 to 30 different and unique detergent- specific 96-condition screens.

  14. Is chronic detergent ingestion harmful to the gut?

    PubMed Central

    Mercurius-Taylor, L A; Jayaraj, A P; Clark, C G

    1984-01-01

    Synthetic detergents are used in large quantities as household and industrial cleaners. Because of the common practice of leaving dishes washed in detergent solutions to dry without rinsing these compounds are ingested. We have calculated that an adult takes in about 1 mg/kg detergent a day and babies can be administered between seven and 10 mg/kg a day. Rats were fed a dose of 100 mg/kg a day in a pilot experiment and gross abnormalities were found in the gastrointestinal tract, the most striking being subtotal villous atrophy of the small bowel mucosa and glandular atrophy in the colon. These changes were not reversible 12 weeks after cessation of detergent administration. Images PMID:6722057

  15. Improved efficiency of budesonide nebulization using surface-active agents.

    PubMed

    Bouwman, A M; Heijstra, M P; Schaefer, N C; Duiverman, E J; Lesouëf, P N; Devadason, S G

    2006-01-01

    Our aim was to improve the efficiency of nebulised budesonide using surface-active agents. Cationic, anionic, and nonionic detergents were added to commercial budesonide suspension, and the particle size distribution during nebulization was measured using both cascade impaction and laser diffraction. Our results showed that the emitted dose was increased after addition of cationic (p < 0.001) and nonionic detergents (p < 0.01) compared with the commercial formulation alone. The respirable fraction was increased for all detergent formulations (p < 0.001) compared with the commercial formulation. We concluded that cationic and nonionic detergent increased the total output of budesonide from the Sidestream. All detergent formulations increased the respirable fraction of nebulized budesonide.

  16. [Membrane lipids and electron transfer. Effects of four detergents on NADH-ferricyanide reductase and NADH-cytochrome c reductase activities of potato tuber microsomes].

    PubMed

    Jolliot, A; Mazliak, P

    1977-10-17

    The NADH-ferricyanure reductase activity of Potato microsomes is stimulated by non ionic detergents (Triton X100 and Tween80) and is partially inhibited by ionic detergents (sodium-cholate and deoxycholate). All these four detergents progressively decreased the NADH-cytochrome c reductase in the following order: sodium deoxycholate greater than Triton X100 greater than sodium cholate greater than Tween80.

  17. Effect of Detergents on the Thermal Behavior of Elastin-like Polypeptides

    PubMed Central

    Thapa, Arjun; Han, Wei; Simons, Robin H.; Chilkoti, Ashutosh; Chi, Eva Y.; López, Gabriel P.

    2012-01-01

    Elastin-like polypeptide (ELP) fusions have been designed to allow large scale, non-chromatographic purification of many soluble proteins using the inverse transition cycling (ITC) method; however, the sensitivity of the aqueous lower critical solubility phase transition temperature (Tt) of ELPs to the addition of cosolutes, including detergents, may be a potential hindrance in purification of proteins with surface hydrophobicity in such a manner. To identify detergents that are known to solubilize such proteins (e.g., membrane proteins) and that have little effect on the Tt of the ELP, we screened a number of detergents with respect to their effects on the Tt and secondary structures of a model ELP (denoted here as ELP180). We found that mild detergents (e.g., DDM, Triton-X100, and CHAPS) do not alter the phase transition behavior or structure (as probed by circular dichroism) of ELP180. This result is in contrast to previous studies that showed a strong effect of other detergents (e.g., SDS) on the Ttof ELPs. Our results clearly indicate that mild detergents do not preclude ITC-based separation of ELPs, and thus that ELP fusions may prove to be useful in the purification of detergent-solubilized recombinant hydrophobic proteins, including membrane proteins, which are otherwise notoriously difficult to extract and purify by conventional separation methods (e.g., chromatography). PMID:23097230

  18. Detergents modify proteinase K resistance of PrPSc in different transmissible spongiform encephalopathies (TSEs)

    PubMed Central

    Breyer, Johanna; Wemheuer, Wiebke M.; Wrede, Arne; Graham, Catherine; Benestad, Sylvie L.; Brenig, Bertram; Richt, Jürgen A.; Schulz-Schaeffer, Walter J.

    2012-01-01

    Prion diseases are diagnosed by the detection of their proteinase K-resistant prion protein fragment (PrPSc). Various biochemical protocols use different detergents for the tissue preparation. We found that the resistance of PrPSc against proteinase K may vary strongly with the detergent used. In our study, we investigated the influence of the most commonly used detergents on eight different TSE agents derived from different species and distinct prion disease forms. For a high throughput we used a membrane adsorbtion assay to detect small amounts of prion aggregates, as well as Western blotting. Tissue lysates were prepared using DOC, SLS, SDS or Triton X-100 in different concentrations and these were digested with various amounts of proteinase K. Detergents are able to enhance or diminish the detectability of PrPSc after proteinase K digestion. Depending on the kind of detergent, its concentration - but also on the host species that developed the TSE and the disease form or prion type - the detectability of PrPSc can be very different. The results obtained here may be helpful during the development or improvement of a PrPSc detection method and they point towards a detergent effect that can be additionally used for decontamination purposes. A plausible explanation for the detergent effects described in this article could be an interaction with the lipids associated with PrPSc that may stabilize the aggregates. PMID:22226540

  19. [Exposure to liquid detergent capsules: a study of the cases reported to the Paris Poison Center, 2011-2012].

    PubMed

    Villa, A; Médernach, C; Arropetian, N; Lagrange, F; Langrand, J; Garnier, R

    2014-06-01

    To evaluate the toxicity of liquid detergent capsules for children. Analysis of 684 consecutive cases from the Paris Poison Center (2011-2012). Most enquiries (97 %) concerned children 5 years of age or younger. The main circumstances of exposure were ingestion alone (72.4 %) or together with eye or skin contact (7.5 % and 7.3 %, respectively). The effects observed were generally due to the irritating properties of concentrated detergents: minor digestive disturbances (particularly vomiting in nearly 50 % of cases) after ingestion and conjunctivitis and/or keratitis after eye contact. The main complications were 24 cases of keratitis and one case of pulmonary toxicity after ingestion. A rash was observed in nine patients; it was delayed in two. The effects observed with liquid detergent capsules were very similar to those resulting from exposure to other detergents. However, exposure to these agents are very frequent and often results in eye contact, which may be responsible for keratitis, and after ingestion detergent inhalation is a possible complication. All cases with eye symptoms or cough after liquid detergent capsule exposure deserve prompt medical examination and assistance. Greater awareness of both health professionals and consumers on the dangers and risks of these laundry detergent pods is required for better treatment of exposure accidents and for their prevention. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  20. Analysis of the solution structure of Thermosynechococcus elongatus photosystem I in n-dodecyl-β-d-maltoside using small-angle neutron scattering and molecular dynamics simulation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Le, Rosemary K.; Harris, Bradley J.; Iwuchukwu, Ifeyinwa J.

    2014-05-01

    Small-angle neutron scattering (SANS) and molecular dynamics (MD) simulation were used to investigate the structure of trimeric photosystem I (PSI) from Thermosynechococcus elongatus (T. elongatus) stabilized in n-dodecyl-β-d-maltoside (DDM) detergent solution. Scattering curves of detergent and protein–detergent complexes were measured at 18% D2O, the contrast match point for the detergent, and 100% D2O, allowing observation of the structures of protein/detergent complexes. It was determined that the maximum dimension of the PSI–DDM complex was consistent with the presence of a monolayer belt of detergent around the periphery of PSI. A dummy-atom reconstruction of the shape of the complex from the SANSmore » data indicates that the detergent envelope has an irregular shape around the hydrophobic periphery of the PSI trimer rather than a uniform, toroidal belt around the complex. A 50 ns MD simulation model (a DDM ring surrounding the PSI complex with extra interstitial DDM) of the PSI–DDM complex was developed for comparison with the SANS data. The results suggest that DDM undergoes additional structuring around the membrane-spanning surface of the complex instead of a simple, relatively uniform belt, as is generally assumed for studies that use detergents to solubilize membrane proteins.« less

  1. Control of occupational asthma and allergy in the detergent industry.

    PubMed

    Sarlo, Katherine

    2003-05-01

    To provide an overview of how a comprehensive preclinical, clinical, and industrial hygiene program has been successfully used to control allergy and asthma to enzymes used in the detergent industry. The author performed a PubMed and ToxLine search of English-language articles with the keywords enzymes, occupational allergy, occupational asthma, detergent, and detergent industry from January 1, 1995, to January 1, 2002. Scientific meeting abstracts, books, and industry association papers on allergy and asthma in the detergent industry were also reviewed. In addition, the practical experience of one major detergent company was included in the review. All published work on this topic was reviewed, and the work that discussed the key highlights of control of occupational allergy and asthma to enzymes used in the detergent industry was selected for this review. The detergent industry has developed guidelines for the safety assessment of enzymes, control of exposure to enzymes, and medical surveillance of enzyme-exposed workers. Because of these guidelines, occupational allergy and asthma to enzymes used in the detergent industry have become uncommon events. Cases of disease have been documented in some manufacturing sites that have had poor adherence to the guidelines. Those manufacturing sites that have adhered to the guidelines have had few cases of allergy and asthma to enzymes among exposed workers. A review of medical data from these sites has shown that workers who have developed IgE antibody to enzymes can continue to work with enzymes and remain symptom free. Occupational allergy and asthma to enzymes used in the detergent industry have been successfully controlled via the use of preclinical, clinical, and industrial hygiene safety programs designed to minimize sensitization to enzymes and development of disease. The basic principles of these programs can be applied to other industries where occupational allergy and asthma to proteins are common.

  2. Preservatives and fragrances in selected consumer-available cosmetics and detergents.

    PubMed

    Yazar, Kerem; Johnsson, Stina; Lind, Marie-Louise; Boman, Anders; Lidén, Carola

    2011-05-01

    Preservatives and fragrances are important and frequent skin sensitizers, found in a wide range of products intended for personal and occupational use. To examine the use of preservatives and fragrances in certain cosmetics and detergents on the market. The product types studied were shampoos, hair conditioners, liquid soaps, wet tissues, washing-up liquids, and multi-purpose cleaners. Ingredient labels of 204 cosmetic products and ingredient data sheets of 97 detergents, available on company websites, were examined. The preservatives most frequently identified were phenoxyethanol, methylparaben, sodium benzoate, propylparaben, and methylchloroisothiazolinone/methylisothiazolinone. Parabens were found in 44% of cosmetics and 9% of detergents; formaldehyde-releasers in 25% of cosmetics and 8% of detergents; and isothiazolinones in 23% of cosmetics and 28% of detergents. The fragrances most frequently identified were linalool, limonene, hexyl cinnamal, butylphenyl methylpropional, and citronellol. Eighty-eight per cent of the products contained fragrances, and any of the 26 fragrances requiring labelling were found in half of the cosmetics and one-third of the detergents. Several preservatives and fragrances with well-known skin-sensitizing potential were common in the examined product types. Such products may be used several times a day by consumers and workers. © 2010 John Wiley & Sons A/S.

  3. Isomeric Detergent Comparison for Membrane Protein Stability: Importance of Inter-Alkyl-Chain Distance and Alkyl Chain Length.

    PubMed

    Cho, Kyung Ho; Hariharan, Parameswaran; Mortensen, Jonas S; Du, Yang; Nielsen, Anne K; Byrne, Bernadette; Kobilka, Brian K; Loland, Claus J; Guan, Lan; Chae, Pil Seok

    2016-12-14

    Membrane proteins encapsulated by detergent micelles are widely used for structural study. Because of their amphipathic property, detergents have the ability to maintain protein solubility and stability in an aqueous medium. However, conventional detergents have serious limitations in their scope and utility, particularly for eukaryotic membrane proteins and membrane protein complexes. Thus, a number of new agents have been devised; some have made significant contributions to membrane protein structural studies. However, few detergent design principles are available. In this study, we prepared meta and ortho isomers of the previously reported para-substituted xylene-linked maltoside amphiphiles (XMAs), along with alkyl chain-length variation. The isomeric XMAs were assessed with three membrane proteins, and the meta isomer with a C 12 alkyl chain was most effective at maintaining solubility/stability of the membrane proteins. We propose that interplay between the hydrophile-lipophile balance (HLB) and alkyl chain length is of central importance for high detergent efficacy. In addition, differences in inter-alkyl-chain distance between the isomers influence the ability of the detergents to stabilise membrane proteins. © 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. 40 CFR 80.140 - Definitions.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... post-refinery component in order to create detergent-additized gasoline or detergent-additized post..., a truck or individual storage tank) at which detergent is blended with gasoline or post-refinery... post-refinery component blended with gasoline, in order to control deposit formation. Carrier oil means...

  5. [Status of the upper respiratory tract of workers in the synthetic detergent industry].

    PubMed

    Artamonova, V G; Barsukov, A F; Galzhiev, A S

    1991-01-01

    Otorhinolaryngologic examinations and functional studies were performed among 99 workers engaged in the production of synthetic detergents. The studies revealed disorders in the barrier and decontamination functions of the nasal ciliary epithelium caused by synthetic detergent dusts.

  6. Quantitative Determination of NTA and Other Chelating Agents in Detergents by Potentiometric Titration with Copper Ion Selective Electrode.

    PubMed

    Ito, Sana; Morita, Masaki

    2016-01-01

    Quantitative analysis of nitrilotriacetate (NTA) in detergents by titration with Cu 2+ solution using a copper ion selective electrode was achieved. This method tolerates a wide range of pH and ingredients in detergents. In addition to NTA, other chelating agents, having relatively lower stability constants toward Cu 2+ , were also qualified with sufficient accuracy by this analytical method for model detergent formulations. The titration process was automated by automatic titrating systems available commercially.

  7. Harmful Effects of Synthetic Surface-Active Detergents against Atopic Dermatitis.

    PubMed

    Deguchi, Hajime; Aoyama, Riho; Takahashi, Hideaki; Isobe, Yoshinari; Tsutsumi, Yutaka

    2015-01-01

    We report herein two cases of intractable atopic dermatitis successfully treated by simply avoiding the contact with surface-active detergents in the daily life and living. The detergents were closely related to the exacerbation and remission of the disease. Steroid ointment was no longer used. We discuss that the removal of horny layer lipids by surface-active detergents accelerates the transepidermal water loss and disturbs the barrier function of the epidermis and thus is intimately involved in the pathogenesis of atopic dermatitis.

  8. Efficacy of detergent and water versus bleach for disinfection of direct contact ophthalmic lenses.

    PubMed

    Abbey, Ashkan M; Gregori, Ninel Z; Surapaneni, Krishna; Miller, Darlene

    2014-06-01

    Although manufacturers recommend cleaning ophthalmic lenses with detergent and water and then with a specific disinfectant, disinfectants are rarely used in ophthalmic practices. The aim of this pilot study was to evaluate the efficacy of detergent and water versus that of bleach, a recommended disinfectant, to eliminate common ocular bacteria and viruses from ophthalmic lenses. Three bacterial strains (Staphylococcus epidermidis, Corynebacterium straitum, and methicillin-resistant Staphylococcus aureus and 2 viral strains (adenovirus and herpes simplex virus [HSV] type-1) were individually inoculated onto 20 gonioscopy and laser lenses. The lenses were washed with detergent and water and then disinfected with 10% bleach. All the lenses were cultured after inoculation, after washing with detergent and water, and after disinfecting with the bleach. Bacterial cultures in thioglycollate broth were observed for 3 weeks, and viral cultures were observed for 2 weeks. The presence of viruses was also detected by multiplex polymerase chain reaction (PCR). All 20 lenses inoculated with S. epidermidis, C. straitum, adenovirus, and HSV-1 showed growth after inoculation but no growth after washing with detergent/water and after disinfecting with the bleach. All lenses showed positive HSV and adenovirus PCR results after inoculation and negative PCR results after washing with detergent/water and after disinfecting with bleach. All methicillin-resistant S. aureus-contaminated lenses showed growth after inoculation and no growth after washing with detergent and water. However, 1 lens showed positive growth after disinfecting with bleach. Cleaning with detergent and water seemed to effectively eliminate bacteria and viruses from the surface of contaminated ophthalmic lenses. Further studies are warranted to design practical disinfection protocols that minimize lens damage.

  9. A compilation of life cycle studies for six household detergent product categories in Europe: the basis for product-specific A.I.S.E. Charter Advanced Sustainability Profiles.

    PubMed

    Golsteijn, Laura; Menkveld, Rimousky; King, Henry; Schneider, Christine; Schowanek, Diederik; Nissen, Sascha

    2015-01-01

    A.I.S.E., the International Association for Soaps, Detergents and Maintenance Products, launched the 'A.I.S.E. Charter for Sustainable Cleaning' in Europe in 2005 to promote sustainability in the cleaning and maintenance products industry. This Charter is a proactive programme for translating the concept of sustainable innovation into reality and actions. Per product category, life cycle assessments (LCA) are used to set sustainability criteria that are ambitious, but also achievable by all market players. This paper presents and discusses LCAs of six household detergent product categories conducted for the Charter, i.e.: manual dishwashing detergents, powder and tablet laundry detergents, window glass trigger spray cleaners, bathroom trigger spray cleaners, acid toilet cleaners, and bleach toilet cleaners. Relevant impact categories are identified, as well as the life cycle stages with the largest contribution to the environmental impact. It was concluded that the variables that mainly drive the results (i.e. the environmental hotspots) for manual dishwashing detergents and laundry detergents were the water temperature, water consumption (for manual dishwashing detergents), product dosage (for laundry detergents), and the choice and amount of surfactant. By contrast, for bathroom trigger sprays, acid and bleach toilet cleaners, the driving factors were plastic packaging, transportation to retailer, and specific ingredients. Additionally, the type of surfactant was important for bleach toilet cleaners. For window glass trigger sprays, the driving factors were the plastic packaging and the type of surfactant, and the other ingredients were of less importance. A.I.S.E. used the results of the studies to establish sustainability criteria, the so-called 'Charter Advanced Sustainability Profiles', which led to improvements in the marketplace.

  10. Maltose Neopentyl Glycol-3 (MNG-3) Analogues for Membrane Protein Study

    PubMed Central

    Cho, Kyung Ho; Husri, Mohd; Amin, Anowarul; Gotfryd, Kamil; Lee, Ho Jin; Go, Juyeon; Kim, Jin Woong; Loland, Claus J.; Guan, Lan; Byrne, Bernadette

    2015-01-01

    Detergents are typically used to both extract membrane proteins (MPs) from the lipid bilayer and maintain them in solution. However, MPs encapsulated in detergent micelles are often prone to denaturation and aggregation. Thus, development of novel agents with enhanced stabilization characteristics is necessary to advance MP research. Maltose neopentyl glycol-3 (MNG-3) has contributed to >10 crystal structures including G-protein coupled receptors. Here we prepared MNG-3 analogues and characterised their properties using selected MPs. Most MNGs behaved superior to a conventional detergent, n–dodecyl–β–D–maltopyranoside (DDM), in terms of membrane protein stabilization efficacy. Interestingly, optimal stabilization was achieved with different MNG-3 analogues depending on the target MP. The origin for such detergent specificity could be explained by a novel concept: compatibility between detergent hydrophobicity and MP tendency to denature and aggregate. This set of MNGs represents viable alternatives to currently available detergents for handling MPs, and can be also used as tools to estimate MP sensitivity to denaturation and aggregation. PMID:25813698

  11. Maltose neopentyl glycol-3 (MNG-3) analogues for membrane protein study.

    PubMed

    Cho, Kyung Ho; Husri, Mohd; Amin, Anowarul; Gotfryd, Kamil; Lee, Ho Jin; Go, Juyeon; Kim, Jin Woong; Loland, Claus J; Guan, Lan; Byrne, Bernadette; Chae, Pil Seok

    2015-05-07

    Detergents are typically used to both extract membrane proteins (MPs) from the lipid bilayers and maintain them in solution. However, MPs encapsulated in detergent micelles are often prone to denaturation and aggregation. Thus, the development of novel agents with enhanced stabilization characteristics is necessary to advance MP research. Maltose neopentyl glycol-3 (MNG-3) has contributed to >10 crystal structures including G-protein coupled receptors. Here, we prepared MNG-3 analogues and characterised their properties using selected MPs. Most MNGs were superior to a conventional detergent, n-dodecyl-β-D-maltopyranoside (DDM), in terms of membrane protein stabilization efficacy. Interestingly, optimal stabilization was achieved with different MNG-3 analogues depending on the target MP. The origin for such detergent specificity could be explained by a novel concept: compatibility between detergent hydrophobicity and MP tendency to denature and aggregate. This set of MNGs represents viable alternatives to currently available detergents for handling MPs, and can be also used as tools to estimate MP sensitivity to denaturation and aggregation.

  12. SANS with contrast variation study of the bacteriorhodopsin-octyl glucoside complex

    NASA Astrophysics Data System (ADS)

    Mo, Yiming; Heller, William T.

    2010-11-01

    Membrane proteins (MPs), which play vital roles in trans-membrane trafficking and signalling between cells and their external environment, comprise a major fraction of the expressed proteomes of many organisms. MP production for biophysical characterization requires detergents for extracting MPs from their native membrane and to solubilize the MP in solution for purification and study. In a proper detergent solution, the detergent-associated MPs retain their native fold and oligomerization state, key requirements for biophysical characterization and crystallization. SANS with contrast variation was performed to characterize BR in complex with OG to better understand the MP-detergent complex. Contrast variation makes it possible to not only probe the conformation of the entire structure but also investigate the conformation of the polypeptide chain within the BR-OG complex. The BR-OG SANS contrast variation series is not consistent with a compact structure, such as a trimeric BR complex surrounded by a belt of detergent. The data strongly suggest that the protein is partially unfolded through its association with the detergent micelles.

  13. The influence of detergents and active components of detergent on bioproduction of organic matters and enzymatic activity of some species of fungi.

    PubMed

    Stojanović, Jelica; Stojanović, Marina; Iles, Deana; Mijusković, Zoran

    2004-01-01

    Detergent (Merix, "Merima " Krusevac) applied in concentration of 1% vol. showed specific influence on the bioproduction of some 15 different amino acids and on the enzyme activity of the species of fungi A. niger, A. alternata and T. roseum. Detergent has significantly stimulated the production of 15 analyzed amino acids of the fungi species A. niger. The same applied concentration of detergent has decreased or considerably decreased the production of some 14 of totally 15 analyzed amino acids of investigated fungi species A. alternata and T. roseum. The enzyme activity of the fungi A. niger was more intensive in relation to the species A. alternata and T. roseum during the experimental period or in some phases of the experimental period. The detergent component, ethoxyled oleyl-cetyl alcohol, in concentration of 0.01%, 0.1% and 1% showed an inhibitory effect, or significant inhibitory effect on the enzyme activity of the examined species of fungi (A. niger, A. alternata and T. roseum).

  14. Detergents enhance EspB secretion from Escherichia coli strains harboring the locus for the enterocyte effacement (LEE) gene.

    PubMed

    Nakasone, Noboru; Toma, Claudia; Higa, Naomi; Koizumi, Yukiko; Ogura, Yasunori; Suzuki, Toshihiko

    2011-02-01

    The effects of detergents (cholic acid, deoxycholic acid, Triton X-100, and Nonidet P-40) on the secretion of EspB from the locus for enterocyte effacement (LEE) gene-positive Escherichia coli strains were examined. Clinical isolates of eight EPEC strains and seven STEC strains were used to detect EspB after they had been cultivated in Luria-Bertani (LB) broth containing one of the detergents. When the bacteria were cultured in LB broth supplemented with one of the detergents, the amount of EspB produced was increased by 2-32-fold depending on the detergent and the strain used. EspB was detected in all strains when they were cultured in LB broth containing all of the detergents. The results obtained in this study can be applied to immunological diagnostic methods for detecting EspB and also to the production of EspB for research purposes. © 2010 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

  15. Effects of a detergent micelle environment on P-glycoprotein (ABCB1)-ligand interactions

    PubMed Central

    Shukla, Suneet; Abel, Biebele; Chufan, Eduardo E.; Ambudkar, Suresh V.

    2017-01-01

    P-glycoprotein (P-gp) is a multidrug transporter that uses energy from ATP hydrolysis to export many structurally dissimilar hydrophobic and amphipathic compounds, including anticancer drugs from cells. Several structural studies on purified P-gp have been reported, but only limited and sometimes conflicting information is available on ligand interactions with the isolated transporter in a dodecyl-maltoside detergent environment. In this report we compared the biochemical properties of P-gp in native membranes, detergent micelles, and when reconstituted in artificial membranes. We found that the modulators zosuquidar, tariquidar, and elacridar stimulated the ATPase activity of purified human or mouse P-gp in a detergent micelle environment. In contrast, these drugs inhibited ATPase activity in native membranes or in proteoliposomes, with IC50 values in the 10–40 nm range. Similarly, a 30–150-fold decrease in the apparent affinity for verapamil and cyclic peptide inhibitor QZ59-SSS was observed in detergent micelles compared with native or artificial membranes. Together, these findings demonstrate that the high-affinity site is inaccessible because of either a conformational change or binding of detergent at the binding site in a detergent micelle environment. The ligands bind to a low-affinity site, resulting in altered modulation of P-gp ATPase activity. We, therefore, recommend studying structural and functional aspects of ligand interactions with purified P-gp and other ATP-binding cassette transporters that transport amphipathic or hydrophobic substrates in a detergent-free native or artificial membrane environment. PMID:28283574

  16. Dendronic trimaltoside amphiphiles (DTMs) for membrane protein study† †Electronic supplementary information (ESI) available. See DOI: 10.1039/c7sc03700g

    PubMed Central

    Sadaf, Aiman; Du, Yang; Santillan, Claudia; Mortensen, Jonas S.; Molist, Iago; Seven, Alpay B.; Hariharan, Parameswaran; Skiniotis, Georgios; Loland, Claus J.; Kobilka, Brian K.; Guan, Lan; Byrne, Bernadette

    2017-01-01

    The critical contribution of membrane proteins in normal cellular function makes their detailed structure and functional analysis essential. Detergents, amphipathic agents with the ability to maintain membrane proteins in a soluble state in aqueous solution, have key roles in membrane protein manipulation. Structural and functional stability is a prerequisite for biophysical characterization. However, many conventional detergents are limited in their ability to stabilize membrane proteins, making development of novel detergents for membrane protein manipulation an important research area. The architecture of a detergent hydrophobic group, that directly interacts with the hydrophobic segment of membrane proteins, is a key factor in dictating their efficacy for both membrane protein solubilization and stabilization. In the current study, we developed two sets of maltoside-based detergents with four alkyl chains by introducing dendronic hydrophobic groups connected to a trimaltoside head group, designated dendronic trimaltosides (DTMs). Representative DTMs conferred enhanced stabilization to multiple membrane proteins compared to the benchmark conventional detergent, DDM. One DTM (i.e., DTM-A6) clearly outperformed DDM in stabilizing human β2 adrenergic receptor (β2AR) and its complex with Gs protein. A further evaluation of this DTM led to a clear visualization of β2AR-Gs complex via electron microscopic analysis. Thus, the current study not only provides novel detergent tools useful for membrane protein study, but also suggests that the dendronic architecture has a role in governing detergent efficacy for membrane protein stabilization. PMID:29619178

  17. Characterization of Protein Detergent Complexes by NMR, Light Scattering, and Analytical Ultracentrifugation

    PubMed Central

    Maslennikov, Innokentiy; Krupa, Martin; Dickson, Christopher; Esquivies, Luis; Blain, Katherine; Kefala, Georgia; Choe, Senyon; Kwiatkowski, Witek

    2009-01-01

    Bottlenecks in expression, solubilization, purification and crystallization hamper the structural study of integral membrane proteins (IMPs). Successful crystallization is critically dependent on the purity, stability and oligomeric homogeneity of an IMP sample. These characteristics are in turn strongly influenced by the type and concentration of the detergents used in IMP preparation. By utilizing the techniques and analytical tools we earlier developed for the characterization of protein-detergent complexes (PDCs) (Maslennikov et al., 2007), we demonstrate that for successful protein extraction from E. coli membrane fractions, the solubilizing detergent associates preferentially to IMPs rather than to membrane lipids. Notably, this result is contrary to the generally accepted mechanism of detergent-mediated IMP solubilization. We find that for one particular member of the family of proteins studied (E. coli receptor kinases, which is purified in mixed multimeric states and oligomerizes through its transmembrane region), the protein oligomeric composition is largely unaffected by a 10-fold increase in protein concentration, by alteration of micelle properties through addition of other detergents to the PDC sample, or by a 20-fold variation in the detergent concentration used for solubilization of the IMP from the membrane. We observed that the conditions used for expression of the IMP, which impact protein density in the membrane, has the greatest influence on the IMP oligomeric structure. Finally, we argue that for concentrating PDCs smaller than 30 kDa, stirred concentration cells are less prone to over-concentration of detergent and are therefore more effective than centrifugal ultrafiltration devices. PMID:19214777

  18. Properties of Zeolite A Obtained from Powdered Laundry Detergent: An Undergraduate Experiment.

    ERIC Educational Resources Information Center

    Smoot, Alison L.; Lindquist, David A.

    1997-01-01

    Presents experiments that introduce students to the myriad properties of zeolites using the sodium form of zeolite A (Na-A) from laundry detergent. Experiments include extracting Na-A from detergent, water softening properties, desiccant properties, ion-exchange properties, and Zeolite HA as a dehydration catalyst. (JRH)

  19. 40 CFR 417.150 - Applicability; description of the manufacture of spray dried detergents subcategory.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 29 2011-07-01 2009-07-01 true Applicability; description of the manufacture of spray dried detergents subcategory. 417.150 Section 417.150 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS SOAP AND DETERGENT MANUFACTURING...

  20. 40 CFR 417.150 - Applicability; description of the manufacture of spray dried detergents subcategory.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 30 2012-07-01 2012-07-01 false Applicability; description of the manufacture of spray dried detergents subcategory. 417.150 Section 417.150 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS SOAP AND DETERGENT MANUFACTURING...

  1. 40 CFR 417.150 - Applicability; description of the manufacture of spray dried detergents subcategory.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 29 2014-07-01 2012-07-01 true Applicability; description of the manufacture of spray dried detergents subcategory. 417.150 Section 417.150 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS SOAP AND DETERGENT MANUFACTURING...

  2. Evaluation of Liquid Detergents and Methods Used for Airfield Rubber Removal

    DTIC Science & Technology

    2012-07-31

    friction. Each detergent is applied to the pavement surface in controlled 50’ x 30’ patches. There were three patches placed for each detergent with...Measurements ..........................................................................................................16 6.3. Periodic Pavement Wetting...19 Figure 14. Pre-Cleaning Micro -Texture Data Graph (GT View Data

  3. 21 CFR 740.17 - Foaming detergent bath products.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 7 2014-04-01 2014-04-01 false Foaming detergent bath products. 740.17 Section 740.17 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) COSMETICS COSMETIC PRODUCT WARNING STATEMENTS Warning Statements § 740.17 Foaming detergent bath products...

  4. 21 CFR 740.17 - Foaming detergent bath products.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 7 2013-04-01 2013-04-01 false Foaming detergent bath products. 740.17 Section 740.17 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) COSMETICS COSMETIC PRODUCT WARNING STATEMENTS Warning Statements § 740.17 Foaming detergent bath products...

  5. 21 CFR 740.17 - Foaming detergent bath products.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 7 2011-04-01 2010-04-01 true Foaming detergent bath products. 740.17 Section 740.17 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) COSMETICS COSMETIC PRODUCT WARNING STATEMENTS Warning Statements § 740.17 Foaming detergent bath products...

  6. 21 CFR 740.17 - Foaming detergent bath products.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 7 2010-04-01 2010-04-01 false Foaming detergent bath products. 740.17 Section 740.17 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) COSMETICS COSMETIC PRODUCT WARNING STATEMENTS Warning Statements § 740.17 Foaming detergent bath products...

  7. 21 CFR 740.17 - Foaming detergent bath products.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 7 2012-04-01 2012-04-01 false Foaming detergent bath products. 740.17 Section 740.17 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) COSMETICS COSMETIC PRODUCT WARNING STATEMENTS Warning Statements § 740.17 Foaming detergent bath products...

  8. Advising parents on washing babies' clothes.

    PubMed

    Scowen, P

    1996-01-01

    Detergents and other laundry products are generally effective and safe for all the family, but use carefully according to the maker's instructions and keep out of the reach of children. Rinse thoroughly to remove detergent residue from fabrics. If handwashing clothes, dissolve detergent before immersing hands. Wear rubber gloves if possible. Wash, rinse and dry hands thoroughly after contact with detergent. If a baby or parent has eczema, it may be necessary to try different products to see which one the client can tolerate. A non-perfumed, non-enzyme product may be found less irritating.

  9. Advances in protease engineering for laundry detergents.

    PubMed

    Vojcic, Ljubica; Pitzler, Christian; Körfer, Georgette; Jakob, Felix; Ronny Martinez; Maurer, Karl-Heinz; Schwaneberg, Ulrich

    2015-12-25

    Proteases are essential ingredients in modern laundry detergents. Over the past 30 years, subtilisin proteases employed in the laundry detergent industry have been engineered by directed evolution and rational design to tailor their properties towards industrial demands. This comprehensive review discusses recent success stories in subtilisin protease engineering. Advances in protease engineering for laundry detergents comprise simultaneous improvement of thermal resistance and activity at low temperatures, a rational strategy to modulate pH profiles, and a general hypothesis for how to increase promiscuous activity towards the production of peroxycarboxylic acids as mild bleaching agents. The three protease engineering campaigns presented provide in-depth analysis of protease properties and have identified principles that can be applied to improve or generate enzyme variants for industrial applications beyond laundry detergents. Copyright © 2015 Elsevier B.V. All rights reserved.

  10. Visualization of Detergent Solubilization of Membranes: Implications for the Isolation of Rafts

    PubMed Central

    Garner, Ashley E.; Smith, D. Alastair; Hooper, Nigel M.

    2008-01-01

    Although different detergents can give rise to detergent-resistant membranes of different composition, it is unclear whether this represents domain heterogeneity in the original membrane. We compared the mechanism of action of five detergents on supported lipid bilayers composed of equimolar sphingomyelin, cholesterol, and dioleoylphosphatidylcholine imaged by atomic force microscopy, and on raft and nonraft marker proteins in live cells imaged by confocal microscopy. There was a marked correlation between the detergent solubilization of the cell membrane and that of the supported lipid bilayers. In both systems Triton X-100 and CHAPS (3-[(3-cholamidopropyl)dimethylammonio]-1-propanesulfonate) distinguished between the nonraft liquid-disordered (ld) and raft liquid ordered (lo) lipid phases by selectively solubilizing the ld phase. A higher concentration of Lubrol was required, and not all the ld phase was solubilized. The solubilization by Brij 96 occurred by a two-stage mechanism that initially resulted in the solubilization of some ld phase and then progressed to the solubilization of both ld and lo phases simultaneously. Octyl glucoside simultaneously solubilized both lo and ld phases. These data show that the mechanism of membrane solubilization is unique to an individual detergent. Our observations have significant implications for using different detergents to isolate membrane rafts from biological systems. PMID:17933878

  11. Visualization of detergent solubilization of membranes: implications for the isolation of rafts.

    PubMed

    Garner, Ashley E; Smith, D Alastair; Hooper, Nigel M

    2008-02-15

    Although different detergents can give rise to detergent-resistant membranes of different composition, it is unclear whether this represents domain heterogeneity in the original membrane. We compared the mechanism of action of five detergents on supported lipid bilayers composed of equimolar sphingomyelin, cholesterol, and dioleoylphosphatidylcholine imaged by atomic force microscopy, and on raft and nonraft marker proteins in live cells imaged by confocal microscopy. There was a marked correlation between the detergent solubilization of the cell membrane and that of the supported lipid bilayers. In both systems Triton X-100 and CHAPS (3-[(3-cholamidopropyl)dimethylammonio]-1-propanesulfonate) distinguished between the nonraft liquid-disordered (l(d)) and raft liquid ordered (l(o)) lipid phases by selectively solubilizing the l(d) phase. A higher concentration of Lubrol was required, and not all the l(d) phase was solubilized. The solubilization by Brij 96 occurred by a two-stage mechanism that initially resulted in the solubilization of some l(d) phase and then progressed to the solubilization of both l(d) and l(o) phases simultaneously. Octyl glucoside simultaneously solubilized both l(o) and l(d) phases. These data show that the mechanism of membrane solubilization is unique to an individual detergent. Our observations have significant implications for using different detergents to isolate membrane rafts from biological systems.

  12. Memprot: a program to model the detergent corona around a membrane protein based on SEC–SAXS data

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Pérez, Javier, E-mail: javier.perez@synchrotron-soleil.fr; Koutsioubas, Alexandros; Synchrotron SOLEIL, L’Orme des Merisiers, BP 48, Saint-Aubin, 91192 Gif-sur-Yvette

    Systematic SAXS simulations have been analysed over a wide range of parameters in order to better understand the detergent corona around a membrane protein. The application of small-angle X-ray scattering (SAXS) to structural investigations of transmembrane proteins in detergent solution has been hampered by two main inherent hurdles. On the one hand, the formation of a detergent corona around the hydrophobic region of the protein strongly modifies the scattering curve of the protein. On the other hand, free micelles of detergent without a precisely known concentration coexist with the protein–detergent complex in solution, therefore adding an uncontrolled signal. To gainmore » robust structural information on such systems from SAXS data, in previous work, advantage was taken of the online combination of size-exclusion chromatography (SEC) and SAXS, and the detergent corona around aquaporin-0, a membrane protein of known structure, could be modelled. A precise geometrical model of the corona, shaped as an elliptical torus, was determined. Here, in order to better understand the correlations between the corona model parameters and to discuss the uniqueness of the model, this work was revisited by analyzing systematic SAXS simulations over a wide range of parameters of the torus.« less

  13. Effects of Detergents on Catalytic Activity of Human Endometase/Matrilysin-2, a Putative Cancer Biomarker†

    PubMed Central

    Park, Hyun I.; Lee, Seakwoo; Ullah, Asad; Cao, Qiang; Sang, Qing-Xiang Amy

    2009-01-01

    Matrix metalloproteinases (MMPs) are a family of hydrolytic enzymes that play significant roles in development, morphogenesis, inflammation, and cancer invasion. Endometase (matrilysin 2 or MMP-26) is a putative early biomarker for human carcinomas. The effects of the ionic and nonionic detergents on catalytic activity of endometase were investigated. The hydrolytic activity of endometase was detergent concentration-dependent exhibiting a bell-shaped curve with its maximum activity near the critical micelle concentration (CMC) of nonionic detergents tested. The effect of Brij-35 on human gelatinase B (MMP-9), matirilysin (MMP-7), and membrane-type 1 MMP (MT1-MMP) was further explored. Their maximum catalysis was observed near the CMC of Brij-35 (~90 μM). Their IC50 values were above the CMC. The inhibition mechanism of MMP-7, MMP-9, and MT1-MMP by Brij-35 was mixed-type as determined by Dixon’s plot, however, that of endometase was non-competitive with a Ki value of 240 μM. The catalytic activities of MMPs are influenced by detergents. Monomer of detergents may activate and stabilize MMPs to enhance catalysis, but micelle of detergents may sequester enzyme and block substrate binding site to impede catalysis. Under physiological conditions lipid or membrane microenvironment may regulate enzymatic activity. PMID:19818727

  14. Identification and absolute quantification of enzymes in laundry detergents by liquid chromatography tandem mass spectrometry.

    PubMed

    Gaubert, Alexandra; Jeudy, Jérémy; Rougemont, Blandine; Bordes, Claire; Lemoine, Jérôme; Casabianca, Hervé; Salvador, Arnaud

    2016-07-01

    In a stricter legislative context, greener detergent formulations are developed. In this way, synthetic surfactants are frequently replaced by bio-sourced surfactants and/or used at lower concentrations in combination with enzymes. In this paper, a LC-MS/MS method was developed for the identification and quantification of enzymes in laundry detergents. Prior to the LC-MS/MS analyses, a specific sample preparation protocol was developed due to matrix complexity (high surfactant percentages). Then for each enzyme family mainly used in detergent formulations (protease, amylase, cellulase, and lipase), specific peptides were identified on a high resolution platform. A LC-MS/MS method was then developed in selected reaction monitoring (SRM) MS mode for the light and corresponding heavy peptides. The method was linear on the peptide concentration ranges 25-1000 ng/mL for protease, lipase, and cellulase; 50-1000 ng/mL for amylase; and 5-1000 ng/mL for cellulase in both water and laundry detergent matrices. The application of the developed analytical strategy to real commercial laundry detergents enabled enzyme identification and absolute quantification. For the first time, identification and absolute quantification of enzymes in laundry detergent was realized by LC-MS/MS in a single run. Graphical Abstract Identification and quantification of enzymes by LC-MS/MS.

  15. Quantifying structural modifications of gills of two fish species Astyanax altiparanae (Lambari) and Prochilodus lineatus (Curimbatá) after exposure to biodegradable detergents in urban lake water.

    PubMed

    Fiorelini Pereira, Bruno; Alves, Anderson Luis; Senhorini, José Augusto; Hakime Scalize, Priscilla; Tocchini De Figueiredo, Fellipe Augusto; Pitol, Dimítrius Leonardo; Caetano, Flávio Henrique

    2017-01-01

    Anthropic actions in rivers and urban lakes are a cause for concern to our ecosystem. The effects on fauna and flora of substances discharged into waterways have become a focus for investigations globally. Biodegradable detergents are widely used in residences and small industries, but little is known regarding the consequences on fish fauna. The objective of the present study was to identify modifications in gill structure in two fish species, Astyanax altiparanae and Prochilodus lineatus, after treatment with water obtained from an urban lake and an exposure to 1 ppm diluted biodegradable detergents (linear alkylbenzene sulfonate). Data demonstrated exposure to urban lake produced various alterations in gill functions such as lamellar fusions, aneurysms, mucous, and chlorine cell proliferation, which may be attributed to the presence of detergents in the water but may also be a consequence of synergetic actions of detergents with other pollutants. Results showed that the levels of NO - 2 , Na, F - , Cl - , and Fe were significantly higher in urban lake water but in the presence of detergents Ni was also detected. Evidence indicates that biodegradable detergents produce damage to gill functions, which subsequently alters the fish physiology and reduces the ability to cope with stress and survival.

  16. Effect of ionic detergents, nonionic detergents, and chaotropic agents on polyphenol oxidase activity from dormant saffron (Crocus sativus L.) corms.

    PubMed

    Saeidian, Shahriar; Keyhani, Ezzatollah; Keyhani, Jacqueline

    2007-05-02

    Polyphenol oxidase (PPO; EC 1.14.18.1) catalyzes the hydroxylation of monophenols to o-diphenols (cresolase activity) and the oxidation of o-diphenols to o-quinones (catecholase activity), leading to browning in plants and produce. Further interest in the enzyme has been triggered by the active role that it plays in plant defense systems. PPO can be found in latent forms and is activated in vitro by various agents including urea, detergents, and proteases. The activation of PPO from several sources by sodium dodecyl sulfate (SDS) has been extensively investigated, but reports on the effect of other detergents or on the differential effect of detergents on each of PPO's activities are scarce. In addition, investigations on the enzyme in other plant parts besides fruits and vegetables are also scarce. Here, the effect of various detergents and chaotropic agents on PPO from dormant saffron (Crocus sativus L.) corm extract was investigated. SDS and sarkosyl activated the cresolase activity, while only SDS activated the catecholase activity. All other detergents tested, in milli- or micromolar concentrations, inhibited the cresolase activity but barely affected the catecholase activity. In contrast, urea and guanidine-HCl drastically inhibited the catecholase activity but moderately inhibited the cresolase activity. The same effects were obtained on the partially purified enzyme. Results identified a PPO, present in dormant corms, which was activated only by anionic detergents and was inhibited by other reputed activating agents such as urea. Results also emphasized the differences in structure and accessibility of the active sites for cresolase and catecholase activities.

  17. Biochemical characterization of detergent-resistant membranes: a systematic approach

    PubMed Central

    Babiychuk, Eduard B.; Draeger, Annette

    2006-01-01

    Lateral segregation of cholesterol- and sphingomyelin-rich rafts and glycerophospholipid-containing non-raft microdomains has been proposed to play a role in a variety of biological processes. The most compelling evidence for membrane segregation is based on the observation that extraction with non-ionic detergents leads to solubilization of a subset of membrane components only. However, one decade later, a large body of inconsistent detergent-extraction data is threatening the very concept of membrane segregation. We have assessed the validity of the existing paradigms and we show the following. (i) The localization of a membrane component within a particular fraction of a sucrose gradient cannot be taken as a yardstick for its solubility: a variable localization of the DRMs (detergent-resistant membranes) in sucrose gradients is the result of complex associations between the membrane skeleton and the lipid bilayer. (ii) DRMs of variable composition can be generated by using a single detergent, the increasing concentration of which gradually extracts one protein/lipid after another. Therefore any extraction pattern obtained by a single concentration experiment is bound to be ‘investigator-specific’. It follows that comparison of DRMs obtained by different detergents in a single concentration experiment is prone to misinterpretations. (iii) Depletion of cholesterol has a graded effect on membrane solubility. (iv) Differences in detergent solubility of the members of the annexin protein family arise from their association with chemically different membrane compartments; however, these cannot be attributed to the ‘brick-like’ raft-building blocks of fixed size and chemical composition. Our findings demonstrate a need for critical re-evaluation of the accumulated detergent-extraction data. PMID:16608442

  18. Biochemical characterization of detergent-resistant membranes: a systematic approach.

    PubMed

    Babiychuk, Eduard B; Draeger, Annette

    2006-08-01

    Lateral segregation of cholesterol- and sphingomyelin-rich rafts and glycerophospholipid-containing non-raft microdomains has been proposed to play a role in a variety of biological processes. The most compelling evidence for membrane segregation is based on the observation that extraction with non-ionic detergents leads to solubilization of a subset of membrane components only. However, one decade later, a large body of inconsistent detergent-extraction data is threatening the very concept of membrane segregation. We have assessed the validity of the existing paradigms and we show the following. (i) The localization of a membrane component within a particular fraction of a sucrose gradient cannot be taken as a yardstick for its solubility: a variable localization of the DRMs (detergent-resistant membranes) in sucrose gradients is the result of complex associations between the membrane skeleton and the lipid bilayer. (ii) DRMs of variable composition can be generated by using a single detergent, the increasing concentration of which gradually extracts one protein/lipid after another. Therefore any extraction pattern obtained by a single concentration experiment is bound to be 'investigator-specific'. It follows that comparison of DRMs obtained by different detergents in a single concentration experiment is prone to misinterpretations. (iii) Depletion of cholesterol has a graded effect on membrane solubility. (iv) Differences in detergent solubility of the members of the annexin protein family arise from their association with chemically different membrane compartments; however, these cannot be attributed to the 'brick-like' raft-building blocks of fixed size and chemical composition. Our findings demonstrate a need for critical re-evaluation of the accumulated detergent-extraction data.

  19. Comparative lipidomics and proteomics analysis of platelet lipid rafts using different detergents.

    PubMed

    Rabani, Vahideh; Davani, Siamak; Gambert-Nicot, Ségolène; Meneveau, Nicolas; Montange, Damien

    2016-11-01

    Lipid rafts play a pivotal role in physiological functions of platelets. Their isolation using nonionic mild detergents is considered as the gold standard method, but there is no consensual detergent for lipid raft studies. We aimed to investigate which detergent is the most suitable for lipid raft isolation from platelet membrane, based on lipidomics and proteomics analysis. Platelets were obtained from healthy donors. Twelve sucrose fractions were extracted by three different detergents, namely Brij 35, Lubrol WX, and Triton X100, at 0.05% and 1%. After lipidomics analysis and determination of fractions enriched in cholesterol (Ch) and sphingomyelin (SM), proteomics analysis was performed. Lipid rafts were mainly observed in 1-4 fractions, and non-rafts were distributed on 5-12 fractions. Considering the concentration of Ch and SM, Lubrol WX 1% and Triton X100 1% were more suitable detergents as they were able to isolate lipid raft fractions that were more enriched than non-raft fractions. By proteomics analysis, overall, 822 proteins were identified in platelet membrane. Lipid raft fractions isolated with Lubrol WX 0.05% and Triton X100 1% contained mainly plasma membrane proteins. However, only Lubrol WX 0.05 and 1% and Triton X100 1% were able to extract non-denaturing proteins with more than 10 transmembrane domains. Our results suggest that Triton X100 1% is the most suitable detergent for global lipid and protein studies on platelet plasma membrane. However, the detergent should be adapted if investigation of an association between specific proteins and lipid rafts is planned.

  20. Use of anionic denaturing detergents to purify insoluble proteins after overexpression

    PubMed Central

    2012-01-01

    Background Many proteins form insoluble protein aggregates, called “inclusion bodies”, when overexpressed in E. coli. This is the biggest obstacle in biotechnology. Ever since the reversible denaturation of proteins by chaotropic agents such as urea or guanidinium hydrochloride had been shown, these compounds were predominantly used to dissolve inclusion bodies. Other denaturants exist but have received much less attention in protein purification. While the anionic, denaturing detergent sodiumdodecylsulphate (SDS) is used extensively in analytical SDS-PAGE, it has rarely been used in preparative purification. Results Here we present a simple and versatile method to purify insoluble, hexahistidine-tagged proteins under denaturing conditions. It is based on dissolution of overexpressing bacterial cells in a buffer containing sodiumdodecylsulfate (SDS) and whole-lysate denaturation of proteins. The excess of detergent is removed by cooling and centrifugation prior to affinity purification. Host- and overexpressed proteins do not co-precipitate with SDS and the residual concentration of detergent is compatible with affinity purification on Ni/NTA resin. We show that SDS can be replaced with another ionic detergent, Sarkosyl, during purification. Key advantages over denaturing purification in urea or guanidinium are speed, ease of use, low cost of denaturant and the compatibility of buffers with automated FPLC. Conclusion Ionic, denaturing detergents are useful in breaking the solubility barrier, a major obstacle in biotechnology. The method we present yields detergent-denatured protein. Methods to refold proteins from a detergent denatured state are known and therefore we propose that the procedure presented herein will be of general application in biotechnology. PMID:23231964

  1. Pediatric exposure to laundry detergent pods.

    PubMed

    Valdez, Amanda L; Casavant, Marcel J; Spiller, Henry A; Chounthirath, Thiphalak; Xiang, Huiyun; Smith, Gary A

    2014-12-01

    Laundry detergent pods are a new product in the US marketplace. This study investigates the epidemiologic characteristics and outcomes of laundry detergent pod exposures among young children in the United States. Using data from the National Poison Data System, exposures to laundry detergent pods among children younger than 6 years of age during 2012-2013 were investigated. There were 17 230 children younger than 6 years exposed to laundry detergent pods in 2012-2013. From March 2012 to April 2013, the monthly number of exposures increased by 645.3%, followed by a 25.1% decrease from April to December 2013. Children younger than 3 years accounted for 73.5% of cases. The major route of exposure was ingestion, accounting for 79.7% of cases. Among exposed children, 4.4% were hospitalized and 7.5% experienced a moderate or major medical outcome. A spectrum of clinical effects from minor to serious was seen with ingestion and ocular exposures. There were 102 patients (0.6%) exposed to a detergent pod via ingestion, aspiration, or a combination of routes, including ingestion, who required tracheal intubation. There was 1 confirmed death. Laundry detergent pods pose a serious poisoning risk to young children. This nationwide study underscores the need for increased efforts to prevent exposure of young children to these products, which may include improvements in product packaging and labeling, development of a voluntary product safety standard, and public education. Product constituent reformulation is another potential strategy to mitigate the severity of clinical effects of laundry detergent pod exposure. Copyright © 2014 by the American Academy of Pediatrics.

  2. 40 CFR 80.161 - Detergent additive certification program.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... the subject detergent additive in each test fuel, and the corresponding test results (percent flow... penalties in §§ 80.169 and 80.172. (iii) If both parties submit the required information, EPA will evaluate... customers who use the disqualified detergent. Failure to do so may subject the certifier to liabilities for...

  3. Imidazoline fuel detergents

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bonazza, B. R.; Holtz, H. D.

    1981-01-27

    A detergent additive imidazoline prepared by reacting carboxylic acid with polyamine is combined into fuel for an internal combustion engine or lubricating oil as a composition suitable for reducing deposits in an internal combustion engine. In an embodiment of the invention, the imidazoline is further combined with a sulfonic acid to obtain a fuel detergent of improved operability.

  4. 40 CFR 180.1022 - Iodine-detergent complex; exemption from the requirement of a tolerance.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Iodine-detergent complex; exemption... FOOD Exemptions From Tolerances § 180.1022 Iodine-detergent complex; exemption from the requirement of a tolerance. The aqueous solution of hydriodic acid and elemental iodine, including one or both of...

  5. 40 CFR 80.169 - Liability for violations of the detergent certification program controls and prohibitions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...-additized PRC satisfied relevant requirements when it left the party's control; and (iii) That the party has... satisfied all relevant requirements when it left the detergent manufacturer's control. (B) Written blending... was manufactured. (2) To establish that, when it left the manufacturer's control, the detergent...

  6. Production of functional bacteriorhodopsin by an Escherichia coli cell-free protein synthesis system supplemented with steroid detergent and lipid.

    PubMed

    Shimono, Kazumi; Goto, Mie; Kikukawa, Takashi; Miyauchi, Seiji; Shirouzu, Mikako; Kamo, Naoki; Yokoyama, Shigeyuki

    2009-10-01

    Cell-free expression has become a highly promising tool for the efficient production of membrane proteins. In this study, we used a dialysis-based Escherichia coli cell-free system for the production of a membrane protein actively integrated into liposomes. The membrane protein was the light-driven proton pump bacteriorhodopsin, consisting of seven transmembrane alpha-helices. The cell-free expression system in the dialysis mode was supplemented with a combination of a detergent and a natural lipid, phosphatidylcholine from egg yolk, in only the reaction mixture. By examining a variety of detergents, we found that the combination of a steroid detergent (digitonin, cholate, or CHAPS) and egg phosphatidylcholine yielded a large amount (0.3-0.7 mg/mL reaction mixture) of the fully functional bacteriorhodopsin. We also analyzed the process of functional expression in our system. The synthesized polypeptide was well protected from aggregation by the detergent-lipid mixed micelles and/or lipid disks, and was integrated into liposomes upon detergent removal by dialysis. This approach might be useful for the high yield production of functional membrane proteins.

  7. A new hydrogen peroxide--based medical-device detergent with germicidal properties: comparison with enzymatic cleaners.

    PubMed

    Alfa, M J; Jackson, M

    2001-06-01

    The objective of this study was to evaluate the efficacy of the cleaning and bacterial killing ability of a new non-enzyme-based formulation (killing detergent solution [KDS]) compared with commercially available enzymatic detergents that included Metrizyme (Metrex Research Division of Sybron Canada Ltd. Morrisburg, Ontario) and Gzyme (Germiphene Corp, Brantford, Ontario). KDS is a hydrogen peroxide-based detergent formulation that combines cleaning efficacy with the ability to kill microorganisms. The KDS formulation helps ensure the protection of the health care worker from infectious risk during the soaking and cleaning stages of medical device reprocessing and reduces the bioburden on devices before sterilization/disinfection. Test organisms that included Enterococcus faecalis, Salmonella choleraesuis, Staphylococcus aureus, and Pseudomonas aeruginosa were suspended in artificial test soil (ATS-B; patent submitted), inoculated at 10(6) colonyforming units per carrier and dried overnight before detergent exposure. The ATS-B mimics the blood, protein, carbohydrate, and endotoxin levels of patient-used medical devices. Plastic lumen carriers and a flexible colonoscope were used for surface and simulated-use testing, respectively. The results for the microbial challenge dried onto polyvinyl chloride (PVC) carriers demonstrated that the ability of KDS to remove protein, blood, carbohydrate, and endotoxin from surface test carriers was as effective as the enzyme detergents that were evaluated. Furthermore, KDS was able to effect approximately a 5-Log(10) reduction in microbial loads with a 3-minute exposure at room temperature, whereas none of the other detergents were as effective. In simulated-use testing of a soiled colonoscope, KDS was significantly better at ensuring microbial killing compared with Gzyme and Metrizyme and was equivalent to the enzymatic detergents in cleaning ability. In summary the KDS has excellent microbial-killing ability in 3-minute exposures at room temperature and cleans as well as the existing enzymatic detergent formulations that were tested.

  8. Insight into the Structure of Light Harvesting Complex II and its Stabilization in Detergent Solution

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Cardoso, Mateus B; Smolensky, Dmitriy; Heller, William T

    2009-01-01

    The structure of spinach light-harvesting complex II (LHC II), stabilized in a solution of the detergent n-octyl-{beta}-d-glucoside (BOG), was investigated by small-angle neutron scattering (SANS). Physicochemical characterization of the isolated complex indicated that it was pure (>95%) and also in its native trimeric state. SANS with contrast variation was used to investigate the properties of the protein-detergent complex at three different H{sub 2}O/D{sub 2}O contrast match points, enabling the scattering properties of the protein and detergent to be investigated independently. The topological shape of LHC II, determined using ab initio shape restoration methods from the SANS data at the contrastmore » match point of BOG, was consistent with the X-ray crystallographic structure of LHC II (Liu et al. Nature 2004 428, 287-292). The interactions of the protein and detergent were investigated at the contrast match point for the protein and also in 100% D{sub 2}O. The data suggested that BOG micelle structure was altered by its interaction with LHC II, but large aggregate structures were not formed. Indirect Fourier transform analysis of the LHC II/BOG scattering curves showed that the increase in the maximum dimension of the protein-detergent complex was consistent with the presence of a monolayer of detergent surrounding the protein. A model of the LHC II/BOG complex was generated to interpret the measurements made in 100% D{sub 2}O. This model adequately reproduced the overall size of the LHC II/BOG complex, but demonstrated that the detergent does not have a highly regular shape that surrounds the hydrophobic periphery of LHC II. In addition to demonstrating that natively structured LHC II can be produced for functional characterization and for use in artificial solar energy applications, the analysis and modeling approaches described here can be used for characterizing detergent-associated {alpha}-helical transmembrane proteins.« less

  9. Evaluation of eco-friendly zwitterionic detergents for enveloped virus inactivation.

    PubMed

    Conley, Lynn; Tao, Yinying; Henry, Alexis; Koepf, Edward; Cecchini, Douglas; Pieracci, John; Ghose, Sanchayita

    2017-04-01

    Inclusion of a detergent in protein biotherapeutic purification processes is a simple and very robust method for inactivating enveloped viruses. The detergent Triton X-100 has been used for many years and is part of the production process of several commercial therapeutic proteins. However, recent ecological studies have suggested that Triton X-100 and its break-down products can potentially behave as endocrine disrupters in aquatic organisms, raising concerns from an environmental impact perspective. As such, discharge of Triton X-100 into the waste water treatment plants is regulated in some jurisdictions, and alternative detergents for viral inactivation are required. In this work, we report on the identification and evaluation of more eco-friendly detergents as viable replacements for Triton X-100. Five detergent candidates with low to moderate environmental impact were initially identified and evaluated with respect to protein stability, followed by proof-of-concept virus inactivation studies using a model enveloped virus. From the set of candidates lauryldimethylamine N-oxide (LDAO) was identified as the most promising detergent due to its low ecotoxicity, robust anti-viral activity (LRV >4 at validation set-point conditions with X-MuLX), and absence of any negative impact on protein function. This detergent exhibited effective and robust virus inactivation in a broad range of protein concentrations, solution conductivities, pHs, and in several different cell culture fluid matrices. The only process parameter which correlated with reduced virus inactivation potency was LDAO concentration, and then only when the concentration was reduced to below the detergent's critical micelle concentration (CMC). Additionally, this work also demonstrated that LDAO was cleared to below detectable levels after Protein A affinity chromatography, making it suitable for use in a platform process that utilizes this chromatographic mode for protein capture. All these findings suggest that LDAO may be a practical alternative to Triton X-100 for use in protein therapeutic production processes for inactivating enveloped viruses. Biotechnol. Bioeng. 2017;114: 813-820. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  10. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Li, Liang; Nachtergaele, Sigrid; Seddon, Annela M.

    This paper utilizes cyclodextrin-based host-guest chemistry in a microfluidic device to modulate the crystallization of membrane proteins and the process of concentration of membrane protein samples. Methyl-{beta}-cyclodextrin (MBCD) can efficiently capture a wide variety of detergents commonly used for the stabilization of membrane proteins by sequestering detergent monomers. Reaction Center (RC) from Blastochloris viridis was used here as a model system. In the process of concentrating membrane protein samples, MBCD was shown to break up free detergent micelles and prevent them from being concentrated. The addition of an optimal amount of MBCD to the RC sample captured loosely bound detergentmore » from the protein-detergent complex and improved sample homogeneity, as characterized by dynamic light scattering. Using plug-based microfluidics, RC crystals were grown in the presence of MBCD, giving a different morphology and space group than crystals grown without MBCD. The crystal structure of RC crystallized in the presence of MBCD was consistent with the changes in packing and crystal contacts hypothesized for removal of loosely bound detergent. The incorporation of MBCD into a plug-based microfluidic crystallization method allows efficient use of limited membrane protein sample by reducing the amount of protein required and combining sparse matrix screening and optimization in one experiment. The use of MBCD for detergent capture can be expanded to develop cyclodextrin-derived molecules for fine-tuned detergent capture and thus modulate membrane protein crystallization in an even more controllable way.« less

  11. Intermolecular detergent-membrane protein noes for the characterization of the dynamics of membrane protein-detergent complexes.

    PubMed

    Eichmann, Cédric; Orts, Julien; Tzitzilonis, Christos; Vögeli, Beat; Smrt, Sean; Lorieau, Justin; Riek, Roland

    2014-12-11

    The interaction between membrane proteins and lipids or lipid mimetics such as detergents is key for the three-dimensional structure and dynamics of membrane proteins. In NMR-based structural studies of membrane proteins, qualitative analysis of intermolecular nuclear Overhauser enhancements (NOEs) or paramagnetic resonance enhancement are used in general to identify the transmembrane segments of a membrane protein. Here, we employed a quantitative characterization of intermolecular NOEs between (1)H of the detergent and (1)H(N) of (2)H-perdeuterated, (15)N-labeled α-helical membrane protein-detergent complexes following the exact NOE (eNOE) approach. Structural considerations suggest that these intermolecular NOEs should show a helical-wheel-type behavior along a transmembrane helix or a membrane-attached helix within a membrane protein as experimentally demonstrated for the complete influenza hemagglutinin fusion domain HAfp23. The partial absence of such a NOE pattern along the amino acid sequence as shown for a truncated variant of HAfp23 and for the Escherichia coli inner membrane protein YidH indicates the presence of large tertiary structure fluctuations such as an opening between helices or the presence of large rotational dynamics of the helices. Detergent-protein NOEs thus appear to be a straightforward probe for a qualitative characterization of structural and dynamical properties of membrane proteins embedded in detergent micelles.

  12. Impact of Detergents on Membrane Protein Complex Isolation.

    PubMed

    Lee, Yu-Chen; Bååth, Jenny Arnling; Bastle, Ryan M; Bhattacharjee, Sonali; Cantoria, Mary Jo; Dornan, Mark; Gamero-Estevez, Enrique; Ford, Lenzie; Halova, Lenka; Kernan, Jennifer; Kürten, Charlotte; Li, Siran; Martinez, Jerahme; Sachan, Nalani; Sarr, Medoune; Shan, Xiwei; Subramanian, Nandhitha; Rivera, Keith; Pappin, Darryl; Lin, Sue-Hwa

    2018-01-05

    Detergents play an essential role during the isolation of membrane protein complexes. Inappropriate use of detergents may affect the native fold of the membrane proteins, their binding to antibodies, or their interaction with partner proteins. Here we used cadherin-11 (Cad11) as an example to examine the impact of detergents on membrane protein complex isolation. We found that mAb 1A5 could immunoprecipitate Cad11 when membranes were solubilized by dodecyl maltoside (DDM) but not by octylglucoside, suggesting that octylglucoside interferes with Cad11-mAb 1A5 interaction. Furthermore, we compared the effects of Brij-35, Triton X-100, cholate, CHAPSO, Zwittergent 3-12, Deoxy BIG CHAP, and digitonin on Cad11 solubilization and immunoprecipitation. We found that all detergents except Brij-35 could solubilize Cad11 from the membrane. Upon immunoprecipitation, we found that β-catenin, a known cadherin-interacting protein, was present in Cad11 immune complex among the detergents tested except Brij-35. However, the association of p120 catenin with Cad11 varied depending on the detergents used. Using isobaric tag for relative and absolute quantitation (iTRAQ) to determine the relative levels of proteins in Cad11 immune complexes, we found that DDM and Triton X-100 were more efficient than cholate in solubilization and immunoprecipitation of Cad11 and resulted in the identification of both canonical and new candidate Cad11-interacting proteins.

  13. Factors Affecting the Discharge of Micro-Plastic Fibers from Household Laundry

    NASA Astrophysics Data System (ADS)

    Lange, N.

    2017-12-01

    Every day millions of loads of laundry are done in in the United States alone. Many, if not most, include synthetic fibers. During washing, micro-plastic fibers are released from the fabric, and discharged into the wastewater. These fibers have been detected in fresh water throughout the world and all of the oceans. These micro-plastic fibers are an emerging environmental contaminant that can adversely affect wildlife and are highly bio-accumulated in aquatic food-chains. Additionally, like other plastics, micro-fibers are not readily biodegraded and persist in the environment for a long time. In this research, I explored the effect of the way we wash clothes on the amount of micro-plastic fibers that are shed by common clothing materials containing man-made fibers. I collected discharge samples from wash and rinse cycles of a washing machine. I collected samples from a control wash using no detergent and then repeated five times. Next, I repeated the experiment five times using four different types of detergent. Large amounts of micro-plastic fibers were released during all wash cycles. However, the numbers decreased during the later rinse cycles. The use of laundry detergent increased the number of micro-plastic fibers released into the wash-water. Deep cleaning detergents produced over ten times more fibers than the no-detergent control. The gentlest detergent only released two times more fibers than the control. Therefore, it would be possible to affect the number of fibers released into the wastewater simply by selection of detergent. The ultimate goal of my research is to develop an optimized detergent that minimizes the number of micro-plastic fibers generated by washing and still effectively clean clothes.

  14. Experimental Analysis of Detergency Phenomena and Investigation of a Next-generation Detergency System.

    PubMed

    Gotoh, Keiko

    2017-01-01

    The detergency of products, mainly textiles, was evaluated using various experimental systems and discussed from the viewpoint of interfacial phenomena. The detergency phenomena observed for geometrically simple model systems were explained in terms of the total potential energy of interaction between the soil and the substrate, which was calculated as the sum of the electrical double layer, Lifshitzvan der Waals, and acid-base interactions using electrokinetic potentials and surface free energy components. Cleaning experiments using artificially soiled fabrics were performed using electro-osmotic flow and ultrasound as mechanical actions for soil removal, and the results were compared with those obtained with mechanical actions commonly used in textile washing. Simultaneous hydrophilization of the substrate and soil by an atmospheric pressure plasma jet remarkably improved the detergency in aqueous solutions. The application of the atmospheric pressure plasma jet to anti-fouling textiles was also proposed.

  15. Membrane preparation and solubilization.

    PubMed

    Roy, Ankita

    2015-01-01

    Membrane proteins play an essential role in several biological processes like ion transport, signal transduction, and electron transfer to name a few. For structural and functional studies of integral membrane proteins, it is critically important to isolate proteins from the membrane using biological detergents. Detergents disrupt the native lipid components of the native membrane and encase the membrane protein in an unnatural environment in aqueous solution. However, a particular membrane protein is best solubilized in a specific detergent; therefore, screening for the optimal detergent is essential. Apart from keeping the membrane protein monodispered in solution, the detergent has to be compatible with downstream processes to isolate and characterize a membrane protein. Over the past several years, a number of membrane proteins have been successfully isolated for structural and functional studies that allowed an outline of general strategies for isolating a novel membrane protein of interest. © 2015 Elsevier Inc. All rights reserved.

  16. Mixing and Matching Detergents for Membrane Protein NMR Structure Determination

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Columbus, Linda; Lipfert, Jan; Jambunathan, Kalyani

    2009-10-21

    One major obstacle to membrane protein structure determination is the selection of a detergent micelle that mimics the native lipid bilayer. Currently, detergents are selected by exhaustive screening because the effects of protein-detergent interactions on protein structure are poorly understood. In this study, the structure and dynamics of an integral membrane protein in different detergents is investigated by nuclear magnetic resonance (NMR) and electron paramagnetic resonance (EPR) spectroscopy and small-angle X-ray scattering (SAXS). The results suggest that matching of the micelle dimensions to the protein's hydrophobic surface avoids exchange processes that reduce the completeness of the NMR observations. Based onmore » these dimensions, several mixed micelles were designed that improved the completeness of NMR observations. These findings provide a basis for the rational design of mixed micelles that may advance membrane protein structure determination by NMR.« less

  17. Optimized formation of detergent micelles of beta-carotene and retinal production using recombinant human beta,beta-carotene 15,15'-monooxygenase.

    PubMed

    Kim, Nam-Hee; Kim, Yeong-Su; Kim, Hye-Jung; Oh, Deok-Kun

    2008-01-01

    The formation of beta-carotene detergent micelles and their conversion into retinal by recombinant human beta,beta-carotene 15,15'-monooxygenase was optimized under aqueous conditions. Toluene was the most hydrophobic among the organic solvents tested; thus, it was used to dissolve beta-carotene, which is a hydrophobic compound. Tween 80 was selected as the detergent because it supported the highest level of retinal production among all of the detergents tested. The maximum production of retinal was achieved in detergent micelles containing 200 mg/L of beta-carotene and 2.4% (w/v) Tween 80. Under these conditions, the recombinant enzyme produced 97 mg/L of retinal after 16 h with a conversion yield of 48.5% (w/w). The amount of retinal produced, which is the highest ever reported, is a result of the ability of our system to dissolve large amounts of beta-carotene.

  18. Impact of detergent systems on bacterial survival on laundered fabrics.

    PubMed Central

    Jaska, J M; Fredell, D L

    1980-01-01

    The survival of Staphylococcus aureus was determined from inoculated swatches laundered in either a phosphate or a phosphate-substitute detergent. In a Plackett-Burman design study, the independent variables of detergent type, concentration, and variation, wash water temperature, soil load, cycle time, and water hardness were assigned high and low values. Wash water temperatures of 27, 38, 49, and 60 degrees C were employed. Viable bacteria were recovered from macerated swatches. Statistical analysis disclosed that there was no practical difference in the ability of phosphate or phosphate-substitute detergents to reduce the level of S. aureus on the laundered swatches in this controlled design. Analysis did reveal that water temperature was the most significant independent variables. The remaining variables did not appear to have any practical significance upon bacterial reduction. This bacteriological study did not evaluate other essential detergent properties. PMID:7377775

  19. Proteolytic Enzymes in Detergents: Evidence of Their Presence through Activity Measurements Based on Electrophoresis

    ERIC Educational Resources Information Center

    Saperas, Nuria; Fonfria-Subiros, Elsa

    2011-01-01

    This laboratory exercise uses a problem-based approach to expose students to some basic concepts relating to proteins and enzymes. One of the main applications of enzymes at the industrial level is their use in the detergent market. The students examine a detergent sample to ascertain whether proteolytic enzymes are a component and, if so, which…

  20. 21 CFR 701.20 - Detergent substances, other than soap, intended for use in cleansing the body.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 7 2013-04-01 2013-04-01 false Detergent substances, other than soap, intended... Ingredients § 701.20 Detergent substances, other than soap, intended for use in cleansing the body. (a) In its definition of the term cosmetic, the Federal Food, Drug, and Cosmetic Act specifically excludes soap. The...

  1. 21 CFR 701.20 - Detergent substances, other than soap, intended for use in cleansing the body.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 7 2012-04-01 2012-04-01 false Detergent substances, other than soap, intended... Ingredients § 701.20 Detergent substances, other than soap, intended for use in cleansing the body. (a) In its definition of the term cosmetic, the Federal Food, Drug, and Cosmetic Act specifically excludes soap. The...

  2. 21 CFR 701.20 - Detergent substances, other than soap, intended for use in cleansing the body.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 7 2014-04-01 2014-04-01 false Detergent substances, other than soap, intended... Ingredients § 701.20 Detergent substances, other than soap, intended for use in cleansing the body. (a) In its definition of the term cosmetic, the Federal Food, Drug, and Cosmetic Act specifically excludes soap. The...

  3. [Effect of natural or synthetic detergents on the transport of D-glucose in the membranes of vesicles of the brush border of the intestine of the rabbit].

    PubMed

    Favilli, F; Iantomasi, T; Stio, M; Treves, C; Vanni, P; Vincenzini, M T

    1988-01-01

    We describe here the effects of natural and synthetic detergents on the D-glucose transport into brush-border membranes of vesicles of rabbit's intestine. Two synthetic detergents: Triton X-100 and dodecyltrimethylammonium bromide have been found very strong inhibitors (more than 50 p. 100 of inhibition of maximal D-glucose uptake). Kinetic studies showed that these detergents behaved as mixed type inhibitors. The Na+-dependent transport of amino acids (aspartic acid, lysine, phenylalanine) is only poorly affected by dodecyltrimethylammonium bromide, while Triton X-100 inhibits unspecifically all the transport studied.

  4. Membrane solubilisation and reconstitution by octylglucoside: comparison of synthetic lipid and natural lipid extract by isothermal titration calorimetry.

    PubMed

    Krylova, Oxana O; Jahnke, Nadin; Keller, Sandro

    2010-08-01

    We have studied the solubilisation and reconstitution of lipid membranes composed of either synthetic phosphatidylcholine or Escherichia. coli polar lipid extract by the non-ionic detergent octylglucoside. For both lipid systems, composition-dependent transformations of unilamellar vesicles into micelles or vice versa were followed by high-sensitivity isothermal titration calorimetry. Data obtained over a range of detergent and lipid concentrations could be rationalised in terms of a three-stage phase separation model involving bilayer, bilayer/micelle coexistence, and micellar ranges, yielding the detergent/lipid phase diagrams and the bilayer-to-micelle partition coefficients of both detergent and lipid. The most notable difference between the lipids investigated was a substantial widening of the bilayer/micelle coexistence range for E. coli lipid, which was due to an increased preference of the detergent and a decreased affinity of the lipid for the micellar phase as compared with the bilayer phase. These effects on the bilayer-to-micelle partition coefficients could be explained by the high proportion in E. coli membranes of lipids possessing negative spontaneous curvature, which hampers both their transfer into strongly curved micellar structures as well as the insertion of detergent into condensed bilayers.

  5. Extensive sphingolipid depletion does not affect lipid raft integrity or lipid raft localization and efflux function of the ABC transporter MRP1.

    PubMed

    Klappe, Karin; Dijkhuis, Anne-Jan; Hummel, Ina; van Dam, Annie; Ivanova, Pavlina T; Milne, Stephen B; Myers, David S; Brown, H Alex; Permentier, Hjalmar; Kok, Jan W

    2010-09-15

    We show that highly efficient depletion of sphingolipids in two different cell lines does not abrogate the ability to isolate Lubrol-based DRMs (detergent-resistant membranes) or detergent-free lipid rafts from these cells. Compared with control, DRM/detergent-free lipid raft fractions contain equal amounts of protein, cholesterol and phospholipid, whereas the classical DRM/lipid raft markers Src, caveolin-1 and flotillin display the same gradient distribution. DRMs/detergent-free lipid rafts themselves are severely depleted of sphingolipids. The fatty acid profile of the remaining sphingolipids as well as that of the glycerophospholipids shows several differences compared with control, most prominently an increase in highly saturated C(16) species. The glycerophospholipid headgroup composition is unchanged in sphingolipid-depleted cells and cell-derived detergent-free lipid rafts. Sphingolipid depletion does not alter the localization of MRP1 (multidrug-resistance-related protein 1) in DRMs/detergent-free lipid rafts or MRP1-mediated efflux of carboxyfluorescein. We conclude that extensive sphingolipid depletion does not affect lipid raft integrity in two cell lines and does not affect the function of the lipid-raft-associated protein MRP1.

  6. Extensive sphingolipid depletion does not affect lipid raft integrity or lipid raft localization and efflux function of the ABC transporter MRP1

    PubMed Central

    Klappe, Karin; Dijkhuis, Anne-Jan; Hummel, Ina; vanDam, Annie; Ivanova, Pavlina T.; Milne, Stephen B.; Myers, David S.; Brown, H. Alex; Permentier, Hjalmar; Kok, Jan W.

    2013-01-01

    We show that highly efficient depletion of sphingolipids in two different cell lines does not abrogate the ability to isolate Lubrol-based DRMs (detergent-resistant membranes) or detergent-free lipid rafts from these cells. Compared with control, DRM/detergent-free lipid raft fractions contain equal amounts of protein, cholesterol and phospholipid, whereas the classical DRM/lipid raft markers Src, caveolin-1 and flotillin display the same gradient distribution. DRMs/detergent-free lipid rafts themselves are severely depleted of sphingolipids. The fatty acid profile of the remaining sphingolipids as well as that of the glycerophospholipids shows several differences compared with control, most prominently an increase in highly saturated C16 species. The glycerophospholipid headgroup composition is unchanged in sphingolipid-depleted cells and cell-derived detergent-free lipid rafts. Sphingolipid depletion does not alter the localization of MRP1 (multidrug-resistance-related protein 1) in DRMs/detergent-free lipid rafts or MRP1-mediated efflux of carboxyfluorescein. We conclude that extensive sphingolipid depletion does not affect lipid raft integrity in two cell lines and does not affect the function of the lipid-raft-associated protein MRP1. PMID:20604746

  7. Membrane proteins, detergents and crystals: what is the state of the art?

    PubMed Central

    Loll, Patrick J.

    2014-01-01

    At the time when the first membrane-protein crystal structure was determined, crystallization of these molecules was widely perceived as extremely arduous. Today, that perception has changed drastically, and the process is regarded as routine (or nearly so). On the occasion of the International Year of Crystallography 2014, this review presents a snapshot of the current state of the art, with an emphasis on the role of detergents in this process. A survey of membrane-protein crystal structures published since 2012 reveals that the direct crystallization of protein–detergent complexes remains the dominant method­ology; in addition, lipidic mesophases have proven immensely useful, particularly in specific niches, and bicelles, while perhaps undervalued, have provided important contributions as well. Evolving trends include the addition of lipids to protein–detergent complexes and the gradual incorporation of new detergents into the standard repertoire. Stability has emerged as a critical parameter controlling how a membrane protein behaves in the presence of detergent, and efforts to enhance stability are discussed. Finally, although discovery-based screening approaches continue to dwarf mechanistic efforts to unravel crystallization, recent technical advances offer hope that future experiments might incorporate the rational manipulation of crystallization behaviors. PMID:25484203

  8. Detergents with different chemical properties induce variable degree of cytotoxicity and mRNA expression of lipid-metabolizing enzymes and differentiation markers in cultured keratinocytes.

    PubMed

    Wei, Tianling; Geijer, Sophia; Lindberg, Magnus; Berne, Berit; Törmä, Hans

    2006-12-01

    The knowledge how detergents with different chemical properties influence epidermal keratinocytes is sparse. In the present study, the effects of five detergents were examined with respect to cell-toxicity and mRNA expression of key-enzymes in barrier lipid production and keratinocyte differentiation markers. First, the LD(50) for each detergent were determined. Secondly, keratinocytes were exposed to sub-toxic concentrations and the mRNA expression was analysed by real-time PCR after 24 h exposure to the detergents. SLS and CAPB induced a concentration-dependent increase in the expression of enzymes producing cholesterol and ceramides, while transcripts of enzymes producing fatty acids were unaffected. SLES and cocoglucoside increased the expression of certain enzymes involved in cholesterol and fatty acid synthesis while sodium cocoamphoacetate (SCAA) stimulated expression of transcripts involved in fatty acid synthesis. The expression of differentiation markers were increased by SLS, SLES and CAPB, while SCAA and cocoglucoside exhibited no effect. The present findings show that detergents have variable effects on lipid synthesis and keratinocyte differentiation, which could partly explain their barrier destruction potential in vivo.

  9. Sublethal detergent concentrations increase metabolization of recalcitrant polyphosphonates by the cyanobacterium Spirulina platensis.

    PubMed

    Forlani, Giuseppe; Bertazzini, Michele; Giberti, Samuele; Wieczorek, Dorota; Kafarski, Paweł; Lipok, Jacek

    2013-05-01

    As a consequence of increasing industrial applications, thousand tons of polyphosphonates are introduced every year into the environment. The inherent stability of the C-P bond results in a prolonged half-life. Moreover, low uptake rates limit further their microbial metabolization. To assess whether low detergent concentrations were able to increase polyphosphonate utilization by the cyanobacterium Spirulina platensis, tolerance limits to the exposure to various detergents were determined by measuring the growth rate in the presence of graded levels below the critical micellar concentration. Then, the amount of hexamethylenediamine-N,N,N',N'-tetrakis(methylphosphonic acid) that is metabolized in the absence or in the presence of sublethal detergent concentrations was quantified by (31)P NMR analysis on either P-starved or P-fed cyanobacterial cultures. The strain tolerated the presence of detergents in the order: nonionic > anionic > cationic. When added to the culture medium at the highest concentrations showing no detrimental effects upon cell viability, detergents either improved or decreased polyphosphonate utilization, the anionic sodium dodecyl sulfate being the most beneficial. Metabolization was not lower in P-fed cells--a result that strengthens the possibility of using, in the future, this strain for bioremediation purposes.

  10. Disinfection of the Skin with Detergent Preparations of Irgasan DP 300 and Other Antiseptics

    PubMed Central

    Lilly, H. A.; Lowbury, E. J. L.

    1974-01-01

    An evaluation of the relative effectiveness of 2% hexachlorophane and 0·75% Irgasan DP 300 bar soaps in disinfection of the hands showed that the former caused a significantly larger reduction in natural skin bacteria than the latter after one handwash and after six handwashings, three on each of two successive days. Repeated use of Irgasan DP 300 bar soap caused a significantly greater reduction in skin flora than repeated handwashings with unmedicated bar soap, but a single handwash gave no significant reduction in skin flora compared with a single use of the unmedicated soap. In a comparison of a 4% chlorhexidine detergent solution a 3% hexachlorophane detergent cream and a 2% Irgasan DP 300 detergent solution the 4% chlorhexidine detergent gave the largest mean reduction in skin bacteria after one handwash and after six handwashings and 2% Irgasan DP 300 a poor and erratic reduction after a single handwash. After six handwashings all three preparations gave large reductions in skin bacteria. The 2% Irgasan preparation showed some residual activity on the skin after handwashing though less than that with chlorhexidine and with hexachlorophane-chlorocresol detergent preparations. PMID:4609556

  11. Outcomes Related to the Use of Frozen Plasma or Pooled Solvent/Detergent-Treated Plasma in Critically Ill Children.

    PubMed

    Camazine, Maraya N; Karam, Oliver; Colvin, Ryan; Leteurtre, Stephane; Demaret, Pierre; Tucci, Marisa; Muszynski, Jennifer A; Stanworth, Simon; Spinella, Philip C

    2017-05-01

    To determine if the use of fresh frozen plasma/frozen plasma 24 hours compared to solvent detergent plasma is associated with international normalized ratio reduction or ICU mortality in critically ill children. This is an a priori secondary analysis of a prospective, observational study. Study groups were defined as those transfused with either fresh frozen plasma/frozen plasma 24 hours or solvent detergent plasma. Outcomes were international normalized ratio reduction and ICU mortality. Multivariable logistic regression was used to determine independent associations. One hundred one PICUs in 21 countries. All critically ill children admitted to a participating unit were included if they received at least one plasma unit during six predefined 1-week (Monday to Friday) periods. All children were exclusively transfused with either fresh frozen plasma/frozen plasma 24 hours or solvent detergent plasma. None. There were 443 patients enrolled in the study. Twenty-four patients (5%) were excluded because no plasma type was recorded; the remaining 419 patients were analyzed. Fresh frozen plasma/frozen plasma 24 hours group included 357 patients, and the solvent detergent plasma group included 62 patients. The median (interquartile range) age and weight were 1 year (0.2-6.4) and 9.4 kg (4.0-21.1), respectively. There was no difference in reason for admission, severity of illness score, pretransfusion international normalized ratio, or lactate values; however, there was a difference in primary indication for plasma transfusion (p < 0.001). There was no difference in median (interquartile range) international normalized ratio reduction, between fresh frozen plasma/frozen plasma 24 hours and solvent detergent plasma study groups, -0.2 (-0.4 to 0) and -0.2 (-0.3 to 0), respectively (p = 0.80). ICU mortality was lower in the solvent detergent plasma versus fresh frozen plasma/frozen plasma 24 hours groups, 14.5% versus 29.1%%, respectively (p = 0.02). Upon adjusted analysis, solvent detergent plasma transfusion was independently associated with reduced ICU mortality (odds ratio, 0.40; 95% CI, 0.16-0.99; p = 0.05). Solvent detergent plasma use in critically ill children may be associated with improved survival. This hypothesis-generating data support a randomized controlled trial comparing solvent detergent plasma to fresh frozen plasma/frozen plasma 24 hours.

  12. Insolubility and redistribution of GPI-anchored proteins at the cell surface after detergent treatment.

    PubMed Central

    Mayor, S; Maxfield, F R

    1995-01-01

    A diverse set of cell surface eukaryotic proteins including receptors, enzymes, and adhesion molecules have a glycosylphosphoinositol-lipid (GPI) modification at the carboxy-terminal end that serves as their sole means of membrane anchoring. These GPI-anchored proteins are poorly solubilized in nonionic detergent such as Triton X-100. In addition these detergent-insoluble complexes from plasma membranes are significantly enriched in several cytoplasmic proteins including nonreceptor-type tyrosine kinases and caveolin/VIP-21, a component of the striated coat of caveolae. These observations have suggested that the detergent-insoluble complexes represent purified caveolar membrane preparations. However, we have recently shown by immunofluorescence and electron microscopy that GPI-anchored proteins are diffusely distributed at the cell surface but may be enriched in caveolae only after cross-linking. Although caveolae occupy only a small fraction of the cell surface (< 4%), almost all of the GPI-anchored protein at the cell surface becomes incorporated into detergent-insoluble low-density complexes. In this paper we show that upon detergent treatment the GPI-anchored proteins are redistributed into a significantly more clustered distribution in the remaining membranous structures. These results show that GPI-anchored proteins are intrinsically detergent-insoluble in the milieu of the plasma membrane, and their co-purification with caveolin is not reflective of their native distribution. These results also indicate that the association of caveolae, GPI-anchored proteins, and signalling proteins must be critically re-examined. Images PMID:7579703

  13. Effect of detergents on the H(+)-ATPase activity of inside-out and right-side-out plant plasma membrane vesicles.

    PubMed

    Palmgren, M G; Sommarin, M; Ulvskov, P; Larsson, C

    1990-01-29

    In search for a detergent to be used to assess the sidedness of plant plasma membrane vesicles by enzyme latency we tested the effect of 42 detergents on the ATPase activity of right-side-out and inside-out plasma membrane vesicles from sugar beet leaves. Most of the detergents seemed to inactivate the ATPase in addition to disrupting the permeability barrier to ATP. There were two main exceptions, namely long chain polyoxyethylene acyl ethers, such as detergents of the Brij series and Lubrol WX, and long chain lysophospholipids. These two types of detergents permeabilized the membranes at low concentrations and did not inhibit the ATPase at higher concentrations. Unmasking of latent active sites seemed to explain the activation of the plasma membrane H(+)-ATPase produced by long chain polyoxyethylene acyl ethers. These detergents should therefore be ideal for determination of vesicle orientation based on ATPase latency. By contrast, long chain lysophospholipids were found to be highly specific activators of the enzyme. In addition, long chain fatty acids were found to strongly inhibit ATP-dependent proton accumulation in the vesicles without inhibiting ATP hydrolysis. This uncoupling effect of the fatty acids could be abolished by the addition of fatty acid-free bovine serum albumin (BSA). Similarly, the proton transport capacity of ageing vesicles could be restored by addition of BSA. The latter findings may explain why isolated plasma membranes so often exhibit increased permeability to protons on ageing.

  14. Detergent-associated solution conformations of helical and beta-barrel membrane proteins.

    PubMed

    Mo, Yiming; Lee, Byung-Kwon; Ankner, John F; Becker, Jeffrey M; Heller, William T

    2008-10-23

    Membrane proteins present major challenges for structural biology. In particular, the production of suitable crystals for high-resolution structural determination continues to be a significant roadblock for developing an atomic-level understanding of these vital cellular systems. The use of detergents for extracting membrane proteins from the native membrane for either crystallization or reconstitution into model lipid membranes for further study is assumed to leave the protein with the proper fold with a belt of detergent encompassing the membrane-spanning segments of the structure. Small-angle X-ray scattering was used to probe the detergent-associated solution conformations of three membrane proteins, namely bacteriorhodopsin (BR), the Ste2p G-protein coupled receptor from Saccharomyces cerevisiae, and the Escherichia coli porin OmpF. The results demonstrate that, contrary to the traditional model of a detergent-associated membrane protein, the helical proteins BR and Ste2p are not in the expected, compact conformation and associated with detergent micelles, while the beta-barrel OmpF is indeed embedded in a disk-like micelle in a properly folded state. The comparison provided by the BR and Ste2p, both members of the 7TM family of helical membrane proteins, further suggests that the interhelical interactions between the transmembrane helices of the two proteins differ, such that BR, like other rhodopsins, can properly refold to crystallize, while Ste2p continues to prove resistant to crystallization from an initially detergent-associated state.

  15. Removal of lead contaminated dusts from hard surfaces.

    PubMed

    Lewis, Roger D; Condoor, Sridhar; Batek, Joe; Ong, Kee Hean; Backer, Denis; Sterling, David; Siria, Jeff; Chen, John J; Ashley, Peter

    2006-01-15

    Government guidelines have widely recommended trisodium phosphate (TSP) or "lead-specific" cleaning detergents for removal of lead-contaminated dust (LCD) from hard surfaces, such as floors and window areas. The purpose of this study was to determine if low-phosphate, non-lead-specific cleaners could be used to efficiently remove LCD from 3 types of surfaces (vinyl flooring, wood, and wallpaper). Laboratory methods were developed and validated for simulating the doping, embedding, and sponge cleaning of the 3 surface types with 4 categories of cleaners: lead-specific detergents, nonionic cleaners, anionic cleaners, and trisodium phosphate (TSP). Vinyl flooring and wood were worn using artificial means. Materials were ashed, followed by ultrasound extraction, and anodic stripping voltammetry (ASV). One-way analysis of variance approach was used to evaluate the surface and detergent effects. Surface type was found to be a significant factor in removal of lead (p < 0.001). Vinyl flooring cleaned better than wallpaper by over 14% and wood cleaned better than wallpaper by 13%. There was no difference between the cleaning action of vinyl flooring and wood. No evidence was found to support the use of TSP or lead-specific detergents over all-purpose cleaning detergents for removal of lead-contaminated dusts. No-phosphate, non-lead-specific detergents are effective in sponge cleaning of lead-contaminated hard surfaces and childhood lead prevention programs should consider recommending all-purpose household detergents for removal of lead-contaminated dust after appropriate vacuuming.

  16. Detergent-associated Solution Conformations of Helical and Beta-barrel Membrane Proteins

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mo, Yiming; Lee, Byung-Kwon; Ankner, John Francis

    2008-01-01

    Membrane proteins present major challenges for structural biology. In particular, the production of suitable crystals for high-resolution structural determination continues to be a significant roadblock for developing an atomic-level understanding of these vital cellular systems. The use of detergents for extracting membrane proteins from the native membrane for either crystallization or reconstitution into model lipid membranes for further study is assumed to leave the protein with the proper fold with a belt of detergent encompassing the membrane-spanning segments of the structure. Small-angle X-ray scattering was used to probe the detergent-associated solution conformations of three membrane proteins, namely bacteriorhodopsin (BR), themore » Ste2p G-protein coupled receptor from Saccharomyces cerevisiae, and the Escherichia coli porin OmpF. The results demonstrate that, contrary to the traditional model of a detergent-associated membrane protein, the helical proteins BR and Ste2p are not in the expected, compact conformation and associated with detergent micelles, while the ?-barrel OmpF is indeed embedded in a disk-like micelle in a properly folded state. The comparison provided by the BR and Ste2p, both members of the 7TM family of helical membrane proteins, further suggests that the interhelical interactions between the transmembrane helices of the two proteins differ, such that BR, like other rhodopsins, can properly refold to crystallize, while Ste2p continues to prove resistant to crystallization from an initially detergent-associated state.« less

  17. Detergent solubilization of the EGF receptor from A431 cells

    NASA Technical Reports Server (NTRS)

    Dayanidhi, R.; Rintoul, D. A.; Spooner, B. S. (Principal Investigator)

    1993-01-01

    Functional reconstitution of purified preparations of human epidermal growth factor receptor (EGFR) requires dissociation of the protein from its plasma membrane lipid environment. Solubilization of membrane proteins in this manner requires the use of detergents, which are known to disrupt plasma membrane lipid/protein interactions. We have investigated the ability of three nonionic detergents to solubilize the human EGFR selectively, and have also analyzed the effect of these various treatments on the intrinsic tyrosyl kinase activity of the receptor. The nonionic detergent known as n-octyl glucoside (n-octyl beta-D-glucopyranoside) was found to give the best combination of selectivity, yield, and maintenance of enzymatic activity of the human EGFR.

  18. Effects of Lubrol detergents on adenylate cyclases.

    PubMed

    Bär, H P; Kulshrestha, S

    1975-04-01

    The nonionic detergent Lubrol WX showed diverse, concentration-dependent effects onbasal and stimulated adenylate cyclases. Above concentrations of 0.001-0.01% Lubrol WX, the basal activity of cyclase from Ehrlich ascites cells was inhibed about 50%, and that from rat fat cells was doubled. In both cases, hormonal sensitivity was lost at 0.01%. These effects were reversed upon dilution of the detergent. It is suggested that solubilization of adenylate cyclases at such low concentrations of Lubrol should be attempted since it is conceivable that loss of hormone sensitivity may then be reversible. Different Lubrol-type detergents may also offer centain advantages, since Lubrol PX effects were not identical with those of Lubrol WX.

  19. Effect of synthetic detergents on germination of fern spores

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Devi, Y.; Devi, S.

    Synthetic detergents constitute one of the most important water pollutants by contaminating the lakes and rivers through domestic and industrial use. Considerable information is now available for the adverse effects of detergents an aquatic fauna including fish, algae, and higher aquatic plants. Marked inhibition of germination in orchids and brinjals and of seedlings growth in raddish suggest that rapidly growing systems could be sensitive to detergent polluted water. The present study of the effect of linear alkyl benzene sulphonate on germination of the spores of a fern, Diplazium esculentum aims at the understanding of the effects of water pollution onmore » pteridophytes and the development of spore germination assay for phytoxicity evaluation.« less

  20. Occupational asthma caused by cellulase and lipase in the detergent industry.

    PubMed

    Brant, A; Hole, A; Cannon, J; Helm, J; Swales, C; Welch, J; Taylor, A Newman; Cullinan, P

    2004-09-01

    Three employees from two different detergent companies were investigated for occupational asthma, using skin prick tests, serum specific IgE, and specific bronchial challenge. Two were challenged with lipase and one with cellulase. All three cases had immunological evidence of sensitisation to the detergent enzymes with which they worked. Bronchial challenge in each provoked a reproducible dual asthmatic response, which reproduced their work related symptoms. These are the first reported cases of occupational asthma attributable to cellulase and lipase in the detergent industry. Four of the most common enzymes used in this industry have now been reported to cause occupational asthma; continued vigilance and caution are needed when working with these or other enzymes.

  1. Highly branched penta-saccharide-bearing amphiphiles for membrane protein studies

    PubMed Central

    Ehsan, Muhammad; Du, Yang; Scull, Nicola J.; Tikhonova, Elena; Tarrasch, Jeffrey; Mortensen, Jonas S.; Loland, Claus J.; Skiniotis, Georgios; Guan, Lan; Byrne, Bernadette; Kobilka, Brian K.; Chae, Pil Seok

    2016-01-01

    Detergents are essential tools for membrane protein manipulation. Micelles formed by detergent molecules have the ability to encapsulate the hydrophobic domains of membrane proteins. The resulting protein-detergent complexes (PDCs) are compatible with the polar environments of aqueous media, making structural and functional analysis feasible. Although a number of novel agents have been developed to overcome the limitations of conventional detergents, most of them have traditional head groups such as glucoside or maltoside. In this study, we introduce a class of amphiphiles, the PSA’Es with a novel highly branched penta-saccharide hydrophilic group. The PSA’Es conferred markedly increased stability to a diverse range of membrane proteins compared to conventional detergents, indicating a positive role for the new hydrophilic group in maintaining the native protein integrity. In addition, PDCs formed by PSA’Es were smaller and more suitable for electron microscopic analysis than those formed by DDM, indicating that the new agents have significant potential for the structure-function studies of membrane proteins. PMID:26966956

  2. Maturation of the Gag core decreases the stability of retroviral lipid membranes.

    PubMed

    Davidoff, Candice; Payne, Riley J; Willis, Sharon H; Doranz, Benjamin J; Rucker, Joseph B

    2012-11-25

    To better understand how detergents disrupt enveloped viruses, we monitored the biophysical stability of murine leukemia virus (MLV) virus-like particles (VLPs) against a panel of commonly used detergents using real-time biosensor measurements. Although exposure to many detergents, such as Triton X-100 and Empigen, results in lysis of VLP membranes, VLPs appeared resistant to complete membrane lysis by a significant number of detergents, including Tween 20, Tween 80, Lubrol, and Saponin. VLPs maintained their structural integrity after exposure to Tween 20 at concentrations up to 500-fold above its CMC. Remarkably, VLPs containing immature cores composed of unprocessed (uncleaved) Gag polyprotein were significantly more resistant to detergent lysis than VLPs with mature cores. Although the maturity of retroviral Gag is known to influence the stability of the protein core structure itself, our studies suggest that the maturity of the Gag core also influences the stability of the lipid bilayer surrounding the core. Copyright © 2012 Elsevier Inc. All rights reserved.

  3. Enzymatic detergent formulation containing amylase from Aspergillus niger: a comparative study with commercial detergent formulations.

    PubMed

    Mitidieri, Sydnei; Souza Martinelli, Anne Helene; Schrank, Augusto; Vainstein, Marilene Henning

    2006-07-01

    There is a wide range of biotechnological applications for amylases, including the textile, pharmaceutical, food and laundry industries. Hydrolytic enzymes are 100% biodegradable and enzymatic detergents can achieve effective cleaning with lukewarm water. Microorganisms and culture media were tested for amylase production and the best producer was Aspergillus niger L119 (3.9 U ml(-1) +/- 0.2) in submerged culture and its amylase demonstrated excellent activity at 50-55 degrees C and pH 4.0, remaining stable at 53 degrees C for up to 200 h. In order to establish the potential uses of this enzyme in detergents, different formulations were tested using the A. niger amylase extract. Enzyme activity was compared with three commercial formulations. The detergents are used in hospitals to clean surgical and endoscopy equipment. The presence of amylase in the formulation is because of its action within hospital drainage system, whether or not it has any function in cleaning the equipment.

  4. Maturation of the Gag core decreases the stability of retroviral lipid membranes

    PubMed Central

    Davidoff, Candice; Payne, Riley; Willis, Sharon H.; Doranz, Benjamin J.; Rucker, Joseph B.

    2012-01-01

    To better understand how detergents disrupt enveloped viruses, we monitored the biophysical stability of murine leukemia virus (MLV) virus-like particles (VLPs) against a panel of commonly used detergents using real-time biosensor measurements. Although exposure to many detergents, such as Triton X-100 and Empigen, results in lysis of VLP membranes, VLPs appeared resistant to complete membrane lysis by a significant number of detergents, including Tween 20, Tween 80, Lubrol, and Saponin. VLPs maintained their structural integrity after exposure to Tween 20 at concentrations up to 500-fold above its CMC. Remarkably, VLPs containing immature cores composed of unprocessed (uncleaved) Gag polyprotein were significantly more resistant to detergent lysis than VLPs with mature cores. Although the maturity of retroviral Gag is known to influence the stability of the protein core structure itself, our studies suggest that the maturity of the Gag core also influences the stability of the lipid bilayer surrounding the core. PMID:22995186

  5. Soaps and detergents: understanding their composition and effect.

    PubMed

    Kirsner, R S; Froelich, C W

    1998-03-01

    Soaps have been used for thousands of years as part of religious ceremonies and daily life. Derived from fatty acids or triglycerides (fats or oils) into their alkali derivatives through a process called saponification, soaps are important for healthcare professionals in preventing the spread of disease. Partly due to their alkaline nature, soaps are limited by their irritancy to the skin and their tendency to form insoluble and inactive salts when combined with either hard water or sea water. Therefore, soap alternatives or synthetic detergents have been developed. Detergents are classified into four groups: anionic, cationic, amphoteric, and non-ionic. These four groups are based on the hydrophilic qualities and surfactants they possess. Each group has characteristics that pertain to its main uses, irritancy, and toxicity. Understanding soaps and detergents may assist clinicians in making intelligent choices when using these agents on their patients as either skin cleansers or wound cleansers. Understanding the characteristics of soaps and detergents is especially important when dealing with at-risk patients such as the elderly.

  6. Evaluation of SDS depletion using an affinity spin column and IMS-MS detection

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hengel, Shawna M.; Floyd, Erica A.; Baker, Erin Shammel

    2012-11-01

    While the use of detergents is necessary for a variety of protein isolation preparation protocols, often prior to mass spectral (MS) analysis, they are not compatible with MS analysis due to ion suppression and adduct formation. This manuscript describes optimization of detergent removal, using commercially available SDS depletion spin columns containing an affinity resin, providing for both increased protein recovery and thorough SDS removal. Ion mobility spectrometry coupled with mass spectrometry (IMS-MS) allowed for a concurrent analysis of both analyte and detergent. In the case of both proteins and peptides, higher detergent concentrations than previously reported provided an increase ofmore » sample recovery; however there was a limit as SDS was detected by IMS-MS at higher levels of SDS indicating incomplete detergent depletion. The results also suggest optimal conditions for SDS removal are dependent on the sample concentration. Overall, this study provides a useful guide for proteomic studies where SDS is required for efficient sample preparation.« less

  7. [On health regulation of synthetic detergents].

    PubMed

    Frolova, A D; Sidorin, G I; Lukovnikova, L V; Skhodkina, N I; D'iakova, L I; Shaposhnikova, E S

    1999-01-01

    The authors present materials on hygienic regulation of such synthetic detergents as "Losk", "Dixan" in air of workplace and populated area, demonstrate results concerning evaluation of "Losk" effects. Discussion covers ways to evaluate chemical load caused by simultaneous emission of synthetic detergents from various environmental objects. For testing reliability of hygienic regulation for complex emission exemplified by "Losk", the authors suggest a model for express evaluation of complex exposure to chemicals.

  8. Determination of the topological shape of integral membrane protein light-harvesting complex LH2 from photosynthetic bacteria in the detergent solution by small-angle X-ray scattering.

    PubMed

    Hong, Xinguo; Weng, Yu-Xiang; Li, Ming

    2004-02-01

    The topological shape of the integral membrane protein light-harvesting complex LH2 from photosynthetic bacteria Rhodobacter spheroides 2.4.1 in detergent solution has been determined from synchrotron small-angle X-ray scattering data using direct curve-fitting by the ellipsoid, ab initio shape determination methods of simulated annealing algorithm and multipole expansion, respectively. The results indicate that the LH2 protein in aqueous solution is encapsulated by a monolayered detergent shell. The detergent-stabilized structure has the shape of an oblate plate, with a thickness of 40 A, a long axis of 110 A, and a short axis of 85 A. After correction for the detergent shell, the shape of the LH2 core is also an oblate plate with a height of 40 A, a long axis of 80 A, and a short axis of 55 A. In contrast to the cylindrical crystal structure with a height of 40 A and a diameter of 68 A, the molecular shape of the LH2 complex in detergent solution clearly deviates from the ringlike crystal structure, with an eccentricity found to be 0.59-consistent with the result of single molecular spectroscopy study of the isolated single LH2 molecules.

  9. Determination of the Topological Shape of Integral Membrane Protein Light-Harvesting Complex LH2 from Photosynthetic Bacteria in the Detergent Solution by Small-Angle X-Ray Scattering

    PubMed Central

    Hong, Xinguo; Weng, Yu-Xiang; Li, Ming

    2004-01-01

    The topological shape of the integral membrane protein light-harvesting complex LH2 from photosynthetic bacteria Rhodobacter spheroides 2.4.1 in detergent solution has been determined from synchrotron small-angle X-ray scattering data using direct curve-fitting by the ellipsoid, ab initio shape determination methods of simulated annealing algorithm and multipole expansion, respectively. The results indicate that the LH2 protein in aqueous solution is encapsulated by a monolayered detergent shell. The detergent-stabilized structure has the shape of an oblate plate, with a thickness of 40 Å, a long axis of 110 Å, and a short axis of 85 Å . After correction for the detergent shell, the shape of the LH2 core is also an oblate plate with a height of 40 Å, a long axis of 80 Å, and a short axis of 55 Å. In contrast to the cylindrical crystal structure with a height of 40 Å and a diameter of 68 Å, the molecular shape of the LH2 complex in detergent solution clearly deviates from the ringlike crystal structure, with an eccentricity found to be 0.59—consistent with the result of single molecular spectroscopy study of the isolated single LH2 molecules. PMID:14747343

  10. Proteomic determination of widespread detergent-insolubility including Abeta but not tau early in the pathogenesis of Alzheimer's disease.

    PubMed

    Woltjer, Randall L; Cimino, P J; Boutté, Angela M; Schantz, Aimee M; Montine, Kathleen S; Larson, Eric B; Bird, Thomas; Quinn, Joseph F; Zhang, Jing; Montine, Thomas J

    2005-11-01

    Biochemical characterization of the major detergent-insoluble proteins that comprise hallmark histopathologic lesions initiated the molecular era of Alzheimer's disease (AD) research. Here, we reinvestigated detergent-insoluble proteins in AD using modern proteomic techniques. Using liquid chromatography (LC)-mass spectrometry (MS)-MS-based proteomics, we robustly identified 125 proteins in the detergent-insoluble fraction of late-onset AD (LOAD) temporal cortex that included several proteins critical to Abeta production, components of synaptic scaffolding, and products of genes linked to an increased risk of LOAD; we verified 15 of 15 of these proteins by Western blot. Following multiple analyses, we estimated that these represent ~80% of detergent-insoluble proteins in LOAD detectable by our method. Abeta, tau, and 7 of 8 other newly identified detergent-insoluble proteins were disproportionately increased in temporal cortex from patients with LOAD and AD derived from mutations in PSEN1 and PSEN2; all of these except tau were elevated in individuals with prodromal dementia, while none except Abeta were elevated in aged APPswe mice. These results are consistent with the amyloid hypothesis of AD and extend it to include widespread protein insolubility, not exclusively Abeta insolubility, early in AD pathogenesis even before the onset of clinical dementia.

  11. [Development and validation of an analytical method to quantify residues of cleaning products able to inactivate prion].

    PubMed

    Briot, T; Robelet, A; Morin, N; Riou, J; Lelièvre, B; Lebelle-Dehaut, A-V

    2016-07-01

    In this study, a novel analytical method to quantify prion inactivating detergent in rinsing waters coming from the washer-disinfector of a hospital sterilization unit has been developed. The final aim was to obtain an easy and functional method in a routine hospital process which does not need the cleaning product manufacturer services. An ICP-MS method based on the potassium dosage of the washer-disinfector's rinsing waters was developed. Potassium hydroxide is present on the composition of the three prion inactivating detergent currently on the French market. The detergent used in this study was the Actanios LDI(®) (Anios laboratories). A Passing and Bablok regression compares concentrations measured with this developed method and with the HPLC-UV manufacturer method. According to results obtained, the developed method is easy to use in a routine hospital process. The Passing and Bablok regression showed that there is no statistical difference between the two analytical methods during the second rinsing step. Besides, both methods were linear on the third rinsing step, with a 1.5ppm difference between the concentrations measured for each method. This study shows that the ICP-MS method developed is nonspecific for the detergent, but specific for the potassium element which is present in all prion inactivating detergent currently on the French market. This method should be functional for all the prion inactivating detergent containing potassium, if the sensibility of the method is sufficient when the potassium concentration is very low in the prion inactivating detergent formulation. Copyright © 2016. Published by Elsevier Masson SAS.

  12. Leptospira santorosai Serovar Shermani detergent extract induces an increase in fibronectin production through a Toll-like receptor 2-mediated pathway.

    PubMed

    Tian, Ya-Chung; Hung, Cheng-Chieh; Li, Yi-Jung; Chen, Yung-Chang; Chang, Ming-Yang; Yen, Tzung-Hai; Hsu, Hsiang-Hao; Wu, Mai-Szu; Phillips, Aled; Yang, Chih-Wei

    2011-03-01

    Leptospirosis can activate inflammatory responses through Toll-like receptors (TLRs) and may cause renal tubulointerstitial fibrosis characterized by the accumulation of extracellular matrix (ECM). We have previously demonstrated that Leptospira santorosai serovar Shermani detergent extract stimulates ECM accumulation in vitro. The aim of this study was to examine the mechanistic basis of these previous observations and, in particular, to examine the potential involvement of TLRs. The addition of serovar Shermani detergent extract led to an increase in fibronectin gene expression and production. Inhibition of TLR2 but not TLR4 expression abrogated serovar Shermani detergent extract-mediated increases in fibronectin production. This response was also blocked by the knockdown of the gene expression of the TLR2 downstream transducers myeloid differentiation factor 88 (MyD88) and tumor necrosis factor receptor-associated factor 6 (TRAF6). Serovar Shermani detergent extract also activated nuclear factor-κB, and its inhibition by curcumin-attenuated serovar Shermani detergent extract induced increases in fibronectin production. These effects were also mimicked by the specific TLR2 agonist, Pam(3)CsK(4), a response that was also abrogated by the knockdown of MyD88 and TRAF6. Similarly, the administration of live leptospires to cells also induced fibronectin production that was blocked by inhibition of TLR2 and MyD88 expression. In conclusion, serovar Shermani detergent extract can induce fibronectin production through the TLR2-associated cascade, providing evidence of an association between TLRs and leptospirosis-mediated ECM deposition.

  13. A Survey of Detergents for the Purification of Stable, Active Human Cystic Fibrosis Transmembrane Conductance Regulator (CFTR)

    PubMed Central

    Hildebrandt, Ellen; Zhang, Qinghai; Cant, Natasha; Ding, Haitao; Dai, Qun; Peng, Lingling; Fu, Yu; DeLucas, Lawrence J.; Ford, Robert; Kappes, John C.; Urbatsch, Ina L.

    2014-01-01

    Structural knowledge of the cystic fibrosis transmembrane conductance regulator (CFTR) requires developing methods to purify and stabilize this aggregation-prone membrane protein above 1 mg/ml. Starting with green fluorescent protein- and epitope-tagged human CFTR produced in mammalian cells known to properly fold and process CFTR, we devised a rapid tandem affinity purification scheme to minimize CFTR exposure to detergent in order to preserve its ATPase function. We compared a panel of detergents, including widely used detergents (maltosides, neopentyl gycols (MNG), C12E8, lysolipids, Chaps) and innovative detergents (branched alkylmaltosides, facial amphiphiles) for CFTR purification, function, monodispersity and stability. ATPase activity after reconstitution into proteoliposomes was 2–3 times higher when CFTR was purified using facial amphiphiles. ATPase activity was also demonstrated in purified CFTR samples without detergent removal using a novel lipid supplementation assay. By electron microscopy, negatively stained CFTR samples were monodisperse at low concentration, and size exclusion chromatography showed a predominance of monomer even after CFTR concentration above 1 mg/ml. Rates of CFTR aggregation quantified in an electrophoretic mobility shift assay showed that detergents which best preserved reconstituted ATPase activity also supported the greatest stability, with CFTR monomer half-lives of 6–9 days in MNG or Chaps, and 12–17 days in facial amphiphile. Cryoelectron microscopy of concentrated CFTR in MNG or facial amphiphile confirmed mostly monomeric protein, producing low resolution reconstructions in conformity with similar proteins. These protocols can be used to generate samples of pure, functional, stable CFTR at concentrations amenable to biophysical characterization. PMID:25065669

  14. Comparative study of the interaction of CHAPS and Triton X-100 with the erythrocyte membrane.

    PubMed

    Rodi, P M; Bocco Gianello, M D; Corregido, M C; Gennaro, A M

    2014-03-01

    The zwitterionic detergent CHAPS, a derivative of the bile salts, is widely used in membrane protein solubilization. It is a "facial" detergent, having a hydrophilic side and a hydrophobic back. The objective of this work is to characterize the interaction of CHAPS with a cell membrane. To this aim, erythrocytes were incubated with a wide range of detergent concentrations in order to determine CHAPS partition behavior, and its effects on membrane lipid order, hemolytic effects, and the solubilization of membrane phospholipids and cholesterol. The results were compared with those obtained with the nonionic detergent Triton X-100. It was found that CHAPS has a low affinity for the erythrocyte membrane (partition coefficient K=0.06mM(-1)), and at sub-hemolytic concentrations it causes little effect on membrane lipid order. CHAPS hemolysis and phospholipid solubilization are closely correlated. On the other side, binding of Triton X-100 disorders the membrane at all levels, and has independent mechanisms for hemolysis and solubilization. Differential behavior was observed in the solubilization of phospholipids and cholesterol. Thus, the detergent resistant membranes (DRM) obtained with the two detergents will have different composition. The behaviors of the two detergents are related to the differences in their molecular structures, suggesting that CHAPS does not penetrate the lipid bilayer but binds in a flat position on the erythrocyte surface, both in intact and cholesterol depleted erythrocytes. A relevant result for Triton X-100 is that hemolysis is not directly correlated with the solubilization of membrane lipids, as it is usually assumed. Copyright © 2013 Elsevier B.V. All rights reserved.

  15. Trends in Thermostability Provide Information on the Nature of Substrate, Inhibitor, and Lipid Interactions with Mitochondrial Carriers*

    PubMed Central

    Crichton, Paul G.; Lee, Yang; Ruprecht, Jonathan J.; Cerson, Elizabeth; Thangaratnarajah, Chancievan; King, Martin S.; Kunji, Edmund R. S.

    2015-01-01

    Mitochondrial carriers, including uncoupling proteins, are unstable in detergents, which hampers structural and mechanistic studies. To investigate carrier stability, we have purified ligand-free carriers and assessed their stability with a fluorescence-based thermostability assay that monitors protein unfolding with a thiol-reactive dye. We find that mitochondrial carriers from both mesophilic and thermophilic organisms exhibit poor stability in mild detergents, indicating that instability is inherent to the protein family. Trends in the thermostability of yeast ADP/ATP carrier AAC2 and ovine uncoupling protein UCP1 allow optimal conditions for stability in detergents to be established but also provide mechanistic insights into the interactions of lipids, substrates, and inhibitors with these proteins. Both proteins exhibit similar stability profiles across various detergents, where stability increases with the size of the associated detergent micelle. Detailed analysis shows that lipids stabilize carriers indirectly by increasing the associated detergent micelle size, but cardiolipin stabilizes by direct interactions as well. Cardiolipin reverses destabilizing effects of ADP and bongkrekic acid on AAC2 and enhances large stabilizing effects of carboxyatractyloside, revealing that this lipid interacts in the m-state and possibly other states of the transport cycle, despite being in a dynamic interface. Fatty acid activators destabilize UCP1 in a similar way, which can also be prevented by cardiolipin, indicating that they interact like transport substrates. Our controls show that carriers can be soluble but unfolded in some commonly used detergents, such as the zwitterionic Fos-choline-12, which emphasizes the need for simple validation assays like the one used here. PMID:25653283

  16. Protein unfolding in detergents: effect of micelle structure, ionic strength, pH, and temperature.

    PubMed Central

    Otzen, Daniel E

    2002-01-01

    The 101-residue monomeric protein S6 unfolds in the anionic detergent sodium dodecyl sulfate (SDS) above the critical micelle concentration, with unfolding rates varying according to two different modes. Our group has proposed that spherical micelles lead to saturation kinetics in unfolding (mode 1), while cylindrical micelles prevalent at higher SDS concentrations induce a power-law dependent increase in the unfolding rate (mode 2). Here I investigate in more detail how micellar properties affect protein unfolding. High NaCl concentrations, which induce cylindrical micelles, favor mode 2. This is consistent with our model, though other effects such as electrostatic screening cannot be discounted. Furthermore, unfolding does not occur in mode 2 in the cationic detergent LTAB, which is unable to form cylindrical micelles. A strong retardation of unfolding occurs at higher LTAB concentrations, possibly due to the formation of dead-end protein-detergent complexes. A similar, albeit much weaker, effect is seen in SDS in the absence of salt. Chymotrypsin inhibitor 2 exhibits the same modes of unfolding in SDS as S6, indicating that this type of protein unfolding is not specific for S6. The unfolding process in mode 1 has an activation barrier similar in magnitude to that in water, while the activation barrier in mode 2 is strongly concentration-dependent. The strong pH-dependence of unfolding in SDS and LTAB suggests that the rate of unfolding in anionic detergent is modulated by repulsion between detergent headgroups and anionic side chains, while cationic side chains modulate unfolding rates in cationic detergents. PMID:12324439

  17. Efficacy of detergents and fresh produce disinfectants against microorganisms associated with mixed raw vegetables.

    PubMed

    Samadi, Nasrin; Abadian, Neda; Bakhtiari, Donya; Fazeli, Mohammad Reza; Jamalifar, Hossein

    2009-07-01

    Efficacy of commercial detergent and disinfectants to eliminate microorganisms associated with fresh vegetables eaten raw in Iran, including radish, parsley, basil, coriander (cilantro), Allium porrum (leek), and peppermint were studied. The raw vegetables were subjected to a triple wash treatment of washing in tap water for mud removal, washing in water containing a detergent (dishwashing liquid) or disinfectant individually, and rinsing in tap water. The population of total mesophilic microbes on the surface of untreated vegetables ranged from 10(5) to 10(6) CFU/g. Washing in tap water or treatment with detergent (333 ppm for 10 min) or benzalkonium chloride (92 ppm for 15 min) reduced the total microbial count, most probable number (MPN) of coliforms, MPN of fecal coliforms, and MPN of fecal streptococci by about 1.2 to 2.3 log. No significant differences in microbial populations were found on vegetables after decontamination with tap water, detergent, or benzalkonium chloride (P > 0.05). Treatments with peracetic acid (100 ppm for 15 min) and hydrogen peroxide (133 ppm for 30 min) reduced the total mesophilic microbial counts by about 2.8 log. The microbial reductions with calcium hypochlorite (300 ppm for 15 min) and combined hydrogen peroxide and silver ion (133 ppm for 30 min) were significantly higher than those obtained after rinsing in tap water or after detergent or benzalkonium chloride wash (P < 0.05). Pretreatment with detergent slightly enhanced the efficacy of all decontamination treatments, but results were not significantly different from those obtained after individual application of disinfectants.

  18. Waste prevention in liquid detergent distribution: a comparison based on life cycle assessment.

    PubMed

    Nessi, Simone; Rigamonti, Lucia; Grosso, Mario

    2014-11-15

    The distribution of liquid detergents through self-dispensing systems has been adopted in some Italian retail stores over the last few years. By enabling the consumer to refill several times the same container, it is proposed as a less waste-generating and more environmentally friendly alternative to the traditional distribution with single-use plastic containers. For this reason, its implementation is encouraged by the national waste prevention programme recently adopted in Italy. In order to assess such claims, a life cycle assessment was carried out to evaluate whether detergent distribution through self-dispensing systems actually allows to achieve the expected reduction in waste generation and environmental impacts. The focus was on the distribution within the large-scale retail trade and on the categories of laundry detergents, fabric softeners and hand dishwashing detergents. For each of them, a set of baseline single-use scenarios were compared with two alternative waste prevention scenarios, where the detergent is distributed through self-dispensing systems. Beyond waste generation, also the Cumulative Energy Demand and thirteen midpoint-level potential impact indicators were calculated for the comparison. Results showed that a reduction in waste generation up to 98% can be achieved, depending on the category of detergent, on the baseline scenario of comparison and on the number of times the refillable container is used. A progressive reduction in the energy demand and in most of the potential impacts was also observed, starting from a minimum number of uses of the refillable container. Copyright © 2014 Elsevier B.V. All rights reserved.

  19. Using detergent to enhance detection sensitivity of African trypanosomes in human CSF and blood by loop-mediated isothermal amplification (LAMP).

    PubMed

    Grab, Dennis J; Nikolskaia, Olga V; Inoue, Noboru; Thekisoe, Oriel M M; Morrison, Liam J; Gibson, Wendy; Dumler, J Stephen

    2011-08-01

    The loop-mediated isothermal amplification (LAMP) assay, with its advantages of simplicity, rapidity and cost effectiveness, has evolved as one of the most sensitive and specific methods for the detection of a broad range of pathogenic microorganisms including African trypanosomes. While many LAMP-based assays are sufficiently sensitive to detect DNA well below the amount present in a single parasite, the detection limit of the assay is restricted by the number of parasites present in the volume of sample assayed; i.e. 1 per µL or 10(3) per mL. We hypothesized that clinical sensitivities that mimic analytical limits based on parasite DNA could be approached or even obtained by simply adding detergent to the samples prior to LAMP assay. For proof of principle we used two different LAMP assays capable of detecting 0.1 fg genomic DNA (0.001 parasite). The assay was tested on dilution series of intact bloodstream form Trypanosoma brucei rhodesiense in human cerebrospinal fluid (CSF) or blood with or without the addition of the detergent Triton X-100 and 60 min incubation at ambient temperature. With human CSF and in the absence of detergent, the LAMP detection limit for live intact parasites using 1 µL of CSF as the source of template was at best 10(3) parasites/mL. Remarkably, detergent enhanced LAMP assay reaches sensitivity about 100 to 1000-fold lower; i.e. 10 to 1 parasite/mL. Similar detergent-mediated increases in LAMP assay analytical sensitivity were also found using DNA extracted from filter paper cards containing blood pretreated with detergent before card spotting or blood samples spotted on detergent pretreated cards. This simple procedure for the enhanced detection of live African trypanosomes in biological fluids by LAMP paves the way for the adaptation of LAMP for the economical and sensitive diagnosis of other protozoan parasites and microorganisms that cause diseases that plague the developing world.

  20. Synthetic detergents induced-biochemical and histological changes in skin of guinea pigs.

    PubMed

    Agarwal, C; Mathur, A K; Gupta, B N; Singh, A; Shanker, R

    1990-06-01

    The linear alkylbenzene sulphonate (LAS) based synthetic detergents-induced decrease in lipid peroxydation and increase in histamine content in exposed skin of guinea pigs in a dose-dependent manner. Histopathological alterations of exposed skin included moderate degree of hyperkeratinization at lower concentration but necrosis, scarring, sloughing as well as discontinuity of epidermis at higher concentrations. The results shows that the contact of skin with detergents causes dermal toxicity.

  1. Effect of some detergents, humate, and composition of seedbed on crop of tomato plants in a hydroponic culture

    NASA Technical Reports Server (NTRS)

    Guminka, A. Z.; Gracz-Nalepka, M.; Lukasiewicz, B.; Sobolewicz, E.; Turkiewicz, I. T.

    1978-01-01

    It is established that single detergent doses distinctly stimulate vegetative development of plants in the initial stage when humates are available. When detergents are applied every four weeks in a hydroponic culture, in which the seedbed does not contain active humates, the crop is reduced by 50%. This adverse effect does not occur when the seedbed is a mixture of brown coal and peat.

  2. Physical-chemical features of non-detergent sulfobetaines active as protein-folding helpers.

    PubMed

    Expert-Bezançon, Nicole; Rabilloud, Thierry; Vuillard, Laurent; Goldberg, Michel E

    2003-01-01

    Some non-detergent sulfobetaines had been shown to prevent aggregation and improve the yield of active proteins when added to the buffer during in vitro protein renaturation. With the aim of designing more efficient folding helpers, a series of non-detergent sulfobetaines have been synthesized and their efficiency in improving the renaturation of a variety of proteins (E. coli tryptophan synthase and beta-D-galactosidase, hen lysozyme, bovine serum albumin, a monoclonal antibody) have been investigated. Attempts to correlate the structure of each sulfobetaines with its effect on folding revealed some molecular features that appear important in helping renaturation. This enabled us to design and synthesize new non-detergent sulfobetaines that act as potent folding helpers.

  3. Optimal Irrigation and Debridement of Infected Joint Implants

    PubMed Central

    Schwechter, Evan M.; Folk, David; Varshney, Avanish K.; Fries, Bettina C.; Kim, Sun Jin; Hirsh, David M.

    2014-01-01

    Acute postoperative and acute, late hematogenous prosthetic joint infections have been treated with 1-stage irrigation and debridement with polyethylene exchange. Success rates, however, are highly variable. Reported studies demonstrate that detergents are effective at decreasing bacterial colony counts on orthopedic implants. Our hypothesis is that the combination of a detergent and an antiseptic would be more effective than using a detergent alone to decrease colony counts from a methicillin-resistant Staphylococcus aureus biofilm-coated titanium alloy disk simulating an orthopedic implant. In our study of various agents tested, chlorhexidine gluconate scrub (antiseptic and detergent) was the most effective at decreasing bacterial colony counts both prereincubation and postreincubation of the disks; pulse lavage and scrubbing were not more effective than pulse lavage alone. PMID:21641757

  4. Differential effects of non-ionic detergents on microsomal and sarcolemmal adenylate cyclase in cardiac muscle

    PubMed Central

    Sulakhe, Prakash V.; Narayanan, Njanoor

    1978-01-01

    1. About 4 and 23% of the homogenate adenylate cyclase activity was recovered in the microsomal and sarcolemmal fractions isolated from guinea-pig heart ventricles. 2. Cardiac microsomal adenylate cyclase activity [basal as well as p[NH]ppG (guanyl-5′-yl imidodiphosphate)- and NaF-stimulated] was increased over 2-fold in the presence of Lubrol-PX (0.01–0.1%). 3. The sarcolemmal enzyme, however, showed concentration-dependent inhibition caused by the detergent under all assay conditions, except when p[NH]ppG was included in the assay. In the latter case, the detergent (0.01–0.02%) caused a modest increase (30–45%) in enzyme activity. 4. Another non-ionic detergent, Triton X-100, also stimulated the microsomal cyclase and inhibited the sarcolemmal enzyme. 5. With either membrane fraction, Lubrol-PX solubilized the enzyme when the detergent/membrane protein ratio was 2.5 (μmol of detergent/mg of protein). 6. The findings with homogenate and a washed particulate fraction resembled those obtained with sarcolemma, and those with isolated sarcoplasmic reticulum resembled those with microsomal preparations. 7. p[NH]ppG, and to some extent NaF, protected the detergent-induced inactivation of the enzyme observed at higher detergent concentrations (0.5% Lubrol-PX and 0.05–0.5% Triton X-100). 8. In the absence of detergents, p[NH]ppG increased the basal enzyme activity about 2-fold in microsomal fractions, but did not appreciably stimulate the sarcolemmal enzyme. Isoproterenol, on the other hand, increased the sarcolemmal enzyme activity (>2-fold) in the presence of p[NH]ppG and caused only moderate stimulation (31%) of the microsomal enzyme under these conditions. 9. These findings support the view that, although the bulk of adenylate cyclase resides in heart sarcolemma (plasma membrane), the microsomal activity cannot be accounted for solely by contamination of the microsomal fraction with sarcolemma, as has been suggested by others [Besch, Jones & Watanabe (1976) Circ. Res. 39, 586–595; Engelhard, Plut & Storm (1976) Biochim. Biophys. Acta 451, 48–61]. Further, the results of this study show that cardiac sarcoplasmic-reticulum membranes possess this enzyme. PMID:736892

  5. Calibration transfer of a Raman spectroscopic quantification method from at-line to in-line assessment of liquid detergent compositions.

    PubMed

    Brouckaert, D; Uyttersprot, J-S; Broeckx, W; De Beer, T

    2017-06-08

    The industrial production of liquid detergent compositions entails delicate balance of ingredients and process steps. In order to assure high quality and productivity in the manufacturing line, process analytical technology tools such as Raman spectroscopy are to be implemented. Marked chemical specificity, negligible water interference and high robustness are ascribed to this process analytical technique. Previously, at-line calibration models have been developed for determining the concentration levels of the being studied liquid detergents main ingredients from Raman spectra. A strategy is now proposed to transfer such at-line developed regression models to an in-line set-up, allowing real-time dosing control of the liquid detergent composition under production. To mimic in-line manufacturing conditions, liquid detergent compositions are created in a five-liter vessel with an overhead mixer. Raman spectra are continuously acquired by pumping the detergent under production via plastic tubing towards a Raman superhead probe, which is incorporated into a metal frame with a sapphire window facing the detergent fluid. Two at-line developed partial least squares (PLS) models are aimed at transferring, predicting the concentration of surfactant 1 and polymer 2 in the examined liquid detergent composition. A univariate slope/bias correction (SBC) is investigated, next to three well-acknowledged multivariate transformation methods: direct, piecewise and double-window piecewise direct standardization. Transfer is considered successful when the magnitude of the validation sets root mean square error of prediction (RMSEP) is similar to or smaller than the corresponding at-line prediction error. The transferred model offering the most promising outcome is further subjected to an exhaustive statistical evaluation, in order to appraise the applicability of the suggested calibration transfer method. Interval hypothesis tests are thereby performed for method comparison. It is illustrated that the investigated transfer approach yields satisfactory results, provided that the original at-line calibration model is thoroughly validated. Both SBC transfer models return lower RMSEP values than their corresponding original models. The surfactant 1 assay met all relevant evaluation criteria, demonstrating successful transfer to the in-line set-up. The in-line quantification of polymer 2 levels in the liquid detergent composition could not be statistically validated, due to the poorer performance of the at-line model. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Bile salts stimulate mucin secretion by cultured dog gallbladder epithelial cells independent of their detergent effect.

    PubMed

    Klinkspoor, J H; Yoshida, T; Lee, S P

    1998-05-15

    1. Bile salts stimulate mucin secretion by the gallbladder epithelium. We have investigated whether this stimulatory effect is due to a detergent effect of bile salts. 2. The bile salts taurocholic acid (TC) and tauroursodeoxycholic acid (TUDC) and the detergents Triton X-100 (12.5-400 microM) and Tween-20 (0.1-3.2 mM) were applied to monolayers of cultured dog gallbladder epithelial cells. Mucin secretion was studied by measuring the secretion of [3H]N-acetyl-d-glucosamine-labelled glycoproteins. We also attempted to alter the fluidity of the apical membrane of the cells through extraction of cholesterol with beta-cyclodextrin (2.5-15 mM). The effect on TUDC-induced mucin secretion was studied. Cell viability was assessed by measuring lactate dehydrogenase (LDH) leakage or 51Cr release. 3. In contrast with the bile salts, the detergents were not able to cause an increase in mucin secretion without causing concomitant cell lysis. Concentrations of detergent that increased mucin release (>100 microM Triton X-100, >0.8 mM Tween-20), caused increased LDH release. Incubation with beta-cyclodextrin resulted in effective extraction of cholesterol without causing an increase in 51Cr release. However, no effect of the presumed altered membrane fluidity on TUDC (10 mM)-induced mucin secretion was observed. 4. The stimulatory effect of bile salts on mucin secretion by gallbladder epithelial cells is not affected by the fluidity of the apical membrane of the cells and also cannot be mimicked by other detergents. We conclude that the ability of bile salts to cause mucin secretion by the gallbladder epithelium is not determined by their detergent properties.

  7. Lack of type 1 sensitization to laundry detergent enzymes among consumers in the Philippines: results of a 2-year study in atopic subjects.

    PubMed

    Cormier, Ethel M; Sarlo, Katherine; Scott, Laurie A; MacKenzie, David P; Payne, Nicholas S; Carr, Gregory J; Smith, Laurence A; Cua-Lim, Felicidad; Bunag, Filipino C; Vasunia, Kersi

    2004-05-01

    Enzymes have been safely used in laundry products for many years. The risk of developing adverse responses to enzymes in laundry detergents among consumers in countries where hand laundry predominates is expected to be low. To understand how consumers in hand laundry markets used detergent products; to show that use of enzyme-containing detergents did not lead to sensitization in an atopic population with compromised skin; and to show that enzyme detergents did not have an adverse effect on skin condition. Women in the rural Philippines were chosen since they do hand laundry for several hours a day, every day. The skin prick test (SPT) tested for the presence of IgE antibody to common aeroallergens and to enzymes in detergent product. Atopic women used enzyme-containing laundry bars for hand laundry and personal cleansing. They also used enzyme-containing laundry granules for hand laundry. All subjects were evaluated by SPT with enzymes over 2 years. Hand and body skin conditions were also evaluated. None of the 1,980 subjects screened for eligibility into the 2-year study were SPT positive to enzymes, including 655 women who used enzyme-containing detergent for up to 1 year. None of the subjects in the study developed IgE to the enzymes. Enzymes had no adverse effect on skin condition or on the development of erosions on the hands. The 2-year study confirms that enzymes are safe for use in laundry products at or below levels tested in the study even when used by atopic consumers under extremely harsh conditions.

  8. A survey of detergents for the purification of stable, active human cystic fibrosis transmembrane conductance regulator (CFTR).

    PubMed

    Hildebrandt, Ellen; Zhang, Qinghai; Cant, Natasha; Ding, Haitao; Dai, Qun; Peng, Lingling; Fu, Yu; DeLucas, Lawrence J; Ford, Robert; Kappes, John C; Urbatsch, Ina L

    2014-11-01

    Structural knowledge of the cystic fibrosis transmembrane conductance regulator (CFTR) requires developing methods to purify and stabilize this aggregation-prone membrane protein above 1mg/ml. Starting with green fluorescent protein- and epitope-tagged human CFTR produced in mammalian cells known to properly fold and process CFTR, we devised a rapid tandem affinity purification scheme to minimize CFTR exposure to detergent in order to preserve its ATPase function. We compared a panel of detergents, including widely used detergents (maltosides, neopentyl glycols (MNG), C12E8, lysolipids, Chaps) and innovative detergents (branched alkylmaltosides, facial amphiphiles) for CFTR purification, function, monodispersity and stability. ATPase activity after reconstitution into proteoliposomes was 2-3 times higher when CFTR was purified using facial amphiphiles. ATPase activity was also demonstrated in purified CFTR samples without detergent removal using a novel lipid supplementation assay. By electron microscopy, negatively stained CFTR samples were monodisperse at low concentration, and size exclusion chromatography showed a predominance of monomer even after CFTR concentration above 1mg/ml. Rates of CFTR aggregation quantified in an electrophoretic mobility shift assay showed that detergents which best preserved reconstituted ATPase activity also supported the greatest stability, with CFTR monomer half-lives of 6-9days in MNG or Chaps, and 12-17days in facial amphiphile. Cryoelectron microscopy of concentrated CFTR in MNG or facial amphiphile confirmed mostly monomeric protein, producing low resolution reconstructions in conformity with similar proteins. These protocols can be used to generate samples of pure, functional, stable CFTR at concentrations amenable to biophysical characterization. Copyright © 2014 Elsevier B.V. All rights reserved.

  9. Effect of three decellularisation protocols on the mechanical behaviour and structural properties of sheep aortic valve conduits.

    PubMed

    Khorramirouz, Reza; Sabetkish, Shabnam; Akbarzadeh, Aram; Muhammadnejad, Ahad; Heidari, Reza; Kajbafzadeh, Abdol-Mohammad

    2014-09-01

    To determine the best method for decellularisation of aortic valve conduits (AVCs) that efficiently removes the cells while preserving the extracellular matrix (ECM) by examining the valvular and conduit sections separately. Sheep AVCs were decellularised by using three different protocols: detergent-based (1% SDS+1% SDC), detergent and enzyme-based (Triton+EDTA+RNase and DNase), and enzyme-based (Trypsin+RNase and DNase) methods. The efficacy of the decellularisation methods to completely remove the cells while preserving the ECM was evaluated by histological evaluation, scanning electron microscopy (SEM), hydroxyproline analysis, tensile test, and DAPI staining. The detergent-based method completely removed the cells and left the ECM and collagen content in the valve and conduit sections relatively well preserved. The detergent and enzyme-based protocol did not completely remove the cells, but left the collagen content in both sections well preserved. ECM deterioration was observed in the aortic valves (AVs), but the ultrastructure of the conduits was well preserved, with no media distortion. The enzyme-based protocol removed the cells relatively well; however, mild structural distortion and poor collagen content was observed in the AVs. Incomplete cell removal (better than that observed with the detergent and enzyme-based protocol), poor collagen preservation, and mild structural distortion were observed in conduits treated with the enzyme-based method. The results suggested that the detergent-based methods are the most effective protocols for cell removal and ECM preservation of AVCs. The AVCs treated with this detergent-based method may be excellent scaffolds for recellularisation. Copyright © 2014 Medical University of Bialystok. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

  10. The impact of detergents on the tissue decellularization process: A ToF-SIMS study.

    PubMed

    White, Lisa J; Taylor, Adam J; Faulk, Denver M; Keane, Timothy J; Saldin, Lindsey T; Reing, Janet E; Swinehart, Ilea T; Turner, Neill J; Ratner, Buddy D; Badylak, Stephen F

    2017-03-01

    Biologic scaffolds are derived from mammalian tissues, which must be decellularized to remove cellular antigens that would otherwise incite an adverse immune response. Although widely used clinically, the optimum balance between cell removal and the disruption of matrix architecture and surface ligand landscape remains a considerable challenge. Here we describe the use of time of flight secondary ion mass spectroscopy (ToF-SIMS) to provide sensitive, molecular specific, localized analysis of detergent decellularized biologic scaffolds. We detected residual detergent fragments, specifically from Triton X-100, sodium deoxycholate and sodium dodecyl sulphate (SDS) in decellularized scaffolds; increased SDS concentrations from 0.1% to 1.0% increased both the intensity of SDS fragments and adverse cell outcomes. We also identified cellular remnants, by detecting phosphate and phosphocholine ions in PAA and CHAPS decellularized scaffolds. The present study demonstrates ToF-SIMS is not only a powerful tool for characterization of biologic scaffold surface molecular functionality, but also enables sensitive assessment of decellularization efficacy. We report here on the use of a highly sensitive analytical technique, time of flight secondary ion mass spectroscopy (ToF-SIMS) to characterize detergent decellularized scaffolds. ToF-SIMS detected cellular remnants and residual detergent fragments; increased intensity of the detergent fragments correlated with adverse cell matrix interactions. This study demonstrates the importance of maintaining a balance between cell removal and detergent disruption of matrix architecture and matrix surface ligand landscape. This study also demonstrates the power of ToF-SIMS for the characterization of decellularized scaffolds and capability for assessment of decellularization efficacy. Future use of biologic scaffolds in clinical tissue reconstruction will benefit from the fundamental results described in this work. Copyright © 2016 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  11. Effects of dietary neutral detergent fiber and starch ratio on rumen epithelial cell morphological structure and gene expression in dairy cows.

    PubMed

    Ma, L; Zhao, M; Zhao, L S; Xu, J C; Loor, J J; Bu, D P

    2017-05-01

    This study was designed to investigate the effect of dietary neutral detergent fiber to starch ratio on rumen epithelial morphological structure and gene expression. Eight primiparous dairy cows including 4 ruminally fistulated cows were assigned to 4 total mixed rations with neutral detergent fiber to starch ratios of 0.86, 1.18, 1.63, and 2.34 in a replicated 4 × 4 Latin square design. The duration of each period was 21 d including 14 d for adaptation and 7 d for sampling. Rumen epithelial papillae were collected from the ruminally fistulated cows for morphological structure examination and mRNA expression analysis using quantitative real-time PCR of several genes related to volatile fatty acid absorption and metabolism, and cellular growth. Increasing dietary neutral detergent fiber to starch ratio resulted in a linear increase in the thickness of the stratum spinosum and basale. In contrast, expression of HMGCS2 (encoding the rate-limiting enzyme in the synthesis of ketone bodies) decreased linearly, whereas the expression of MCT2 (encoding a transporter of volatile fatty acid) increased linearly with increasing dietary neutral detergent fiber to starch ratio. As dietary neutral detergent fiber to starch ratio increased, expression of IGFBP5 (a gene related to the growth of rumen epithelial papillae) decreased, whereas IGFBP6 expression increased. Both of these IGFBP genes are regulated by short-chain fatty acids. Overall, the data indicate that dietary neutral detergent fiber to starch ratio can alter the thickness of the rumen epithelial papillae partly through changes in expression of genes associated with regulating volatile fatty acid absorption, metabolism, and cell growth. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  12. Evaluation of detergents for the soluble expression of alpha-helical and beta-barrel-type integral membrane proteins by a preparative scale individual cell-free expression system.

    PubMed

    Klammt, Christian; Schwarz, Daniel; Fendler, Klaus; Haase, Winfried; Dötsch, Volker; Bernhard, Frank

    2005-12-01

    Cell-free expression has become a highly promising tool for the fast and efficient production of integral membrane proteins. The proteins can be produced as precipitates that solubilize in mild detergents usually without any prior denaturation steps. Alternatively, membrane proteins can be synthesized in a soluble form by adding detergents to the cell-free system. However, the effects of a representative variety of detergents on the production, solubility and activity of a wider range of membrane proteins upon cell-free expression are currently unknown. We therefore analyzed the cell-free expression of three structurally very different membrane proteins, namely the bacterial alpha-helical multidrug transporter, EmrE, the beta-barrel nucleoside transporter, Tsx, and the porcine vasopressin receptor of the eukaryotic superfamily of G-protein coupled receptors. All three membrane proteins could be produced in amounts of several mg per one ml of reaction mixture. In general, the detergent 1-myristoyl-2-hydroxy-sn-glycero-3-[phospho-rac-(1-glycerol)] was found to be most effective for the resolubilization of membrane protein precipitates, while long chain polyoxyethylene-alkyl-ethers proved to be most suitable for the soluble expression of all three types of membrane proteins. The yield of soluble expressed membrane protein remained relatively stable above a certain threshold concentration of the detergents. We report, for the first time, the high-level cell-free expression of a beta-barrel type membrane protein in a functional form. Structural and functional variations of the analyzed membrane proteins are evident that correspond with the mode of expression and that depend on the supplied detergent.

  13. Reported toxicity in 1486 liquid detergent capsule exposures to the UK National Poisons Information Service 2009-2012, including their ophthalmic and CNS effects.

    PubMed

    Williams, Hayley; Jones, Stephen; Wood, Kelly; Scott, Robert A H; Eddleston, Michael; Thomas, Simon H L; Thompson, John Paul; Vale, J Allister

    2014-02-01

    CONTEXT. Data on the ophthalmic and central nervous system (CNS) adverse effects of liquid detergent capsules (liquid laundry pods) are limited. OBJECTIVE. To ascertain the reported toxicity of liquid detergent capsules, particularly their ophthalmic and CNS adverse effects, in a large case series. METHODS. Between 1 May 2009 and 30 July 2012 the UK National Poisons Information Service collected prospectively 1509 telephone enquiries (involving 1486 exposures) relating to liquid detergent capsules. RESULTS. The majority of patients (95.6%) were children aged less than 5. Exposure to these products occurred mainly as a result of ingestion alone (n = 1215; 81.8%), with eye contact alone (n = 110; 7.4%), and skin contact alone (n = 20; 1.3%) being less common; multiple routes of exposure were involved in 141 (9.5%) cases. Following ocular exposure (n = 212), features suggesting conjunctivitis (n = 145; 68.4%) and corneal ulceration (n = 6; 2.8%) developed. The most common features reported following ingestion alone were nausea and vomiting (n = 721; 59.3%), followed by coughing (n = 53; 4.4%), drowsiness/CNS depression (n = 49; 42 of these were children were aged 2 years or less) and foaming at the mouth (n = 47; 3.9%). A rash occurred in 22 patients where ingestion was considered to be the route of exposure. Twenty patients were exposed via the dermal route alone and developed erythema (n = 9), rash (n = 6) and burn (n = 3). CONCLUSIONS. Ocular exposure to liquid detergent capsules may lead to conjunctivitis and corneal ulceration; detergent ingestion may result in central nervous system (CNS)depression. Greater consumer awareness is required to reduce injury from liquid detergent capsules, particularly that involving the eye.

  14. False-positive pregnancy test after transfusion of solvent/detergent-treated plasma.

    PubMed

    Jilma-Stohlawetz, Petra; Wreford-Bush, Tim; Mills, Francesca; Davidson, Fiona; Kursten, Friedrich W; Jilma, Bernd; Birchall, Janet

    2017-12-01

    The transmission of pathogens, antibodies, and proteins is a possible consequence of blood product transfusion. A female patient had an unexpected positive serum β-human chorionic gonadotropin result, indicative of pregnancy, after she had received a transfusion with 1 unit of platelet concentrate, 4 units of red blood cells, and 4 units of pooled solvent/detergent-treated plasma (Octaplas). To investigate the possibility of passive transfusion of β-human chorionic gonadotropin from the plasma transfusion, one additional unit from the same batch was thawed and analyzed. To validate the β-human chorionic gonadotropin assay for use in solvent/detergent-treated plasma and to investigate any interference in the assay, dilution experiments were performed using the implicated plasma batch diluted with male and non-pregnant female sera. Also, plasma from a known pregnant woman was diluted with Octaplas (tested negative for β-human chorionic gonadotropin) and with a male serum to validate the assay for use in solvent/detergent-treated plasma. The implicated solvent/detergent-treated plasma had a mean β-human chorionic gonadotropin level of 91.5 mIU/mL. Results from the dilution experiments revealed an excellent correlation (r > 0.99) between β-human chorionic gonadotropin measurement in solvent/detergent-treated plasma and male serum and no over or under recovery of the expected results. Further measurements of β-human chorionic gonadotropin levels in the female recipient revealed an estimated half-life of 6 hours. This case demonstrates the importance of considering the possibility of passive transmission of analytes to a patient from the transfusion of blood products. Furthermore, the measurement of β-human chorionic gonadotropin is valid in solvent/detergent-treated plasma using a Roche Cobas analyzer. © 2017 AABB.

  15. Influence of detergents on water drift in cooling towers

    NASA Astrophysics Data System (ADS)

    Vitkovicova, Rut

    An influence of detergents on the water drift from the cooling tower was experimentally investigated. For this experimental measurements was used a model cooling tower, especially an experimental aerodynamic line, which is specially designed for the measurement and monitoring of processes taking place around the eliminators of the liquid phase. The effect of different concentrations of detergent in the cooling water on the drift of water droplets from a commonly used type eliminator was observed with visualization methods.

  16. A comparative spectroscopic and kinetic study of photoexcitations in detergent-isolated and membrane-embedded LH2 light-harvesting complexes.

    PubMed

    Freiberg, Arvi; Rätsep, Margus; Timpmann, Kõu

    2012-08-01

    Integral membrane proteins constitute more than third of the total number of proteins present in organisms. Solubilization with mild detergents is a common technique to study the structure, dynamics, and catalytic activity of these proteins in purified form. However beneficial the use of detergents may be for protein extraction, the membrane proteins are often denatured by detergent solubilization as a result of native lipid membrane interactions having been modified. Versatile investigations of the properties of membrane-embedded and detergent-isolated proteins are, therefore, required to evaluate the consequences of the solubilization procedure. Herein, the spectroscopic and kinetic fingerprints have been established that distinguish excitons in individual detergent-solubilized LH2 light-harvesting pigment-protein complexes from them in the membrane-embedded complexes of purple photosynthetic bacteria Rhodobacter sphaeroides. A wide arsenal of spectroscopic techniques in visible optical range that include conventional broadband absorption-fluorescence, fluorescence anisotropy excitation, spectrally selective hole burning and fluorescence line-narrowing, and transient absorption-fluorescence have been applied over broad temperature range between physiological and liquid He temperatures. Significant changes in energetics and dynamics of the antenna excitons upon self-assembly of the proteins into intracytoplasmic membranes are observed, analyzed, and discussed. This article is part of a Special Issue entitled: Photosynthesis Research for Sustainability: from Natural to Artificial. Copyright © 2011. Published by Elsevier B.V.

  17. Synthetic detergents: 100 years of history.

    PubMed

    Kogawa, Ana Carolina; Cernic, Beatriz Gamberini; do Couto, Leandro Giovanni Domingos; Salgado, Hérida Regina Nunes

    2017-09-01

    In the year 2016 the synthetic detergents complete 100 years and in this story they evolved as cleaners. They are already part of the routine of thousands of people worldwide. For a higher power of cleaning of the detergent, today, are added phosphates, the main responsible for environmental problems. After 100 years of synthetic detergents, the effect of the combination of various cleaners on the environment is a gap. Legislation and guidelines about the other components of the formula of cleaners still missing. Even the term biodegradable can be best placed on the diversity of products currently entitled biodegradable. A lot attitudes can still be taken to continuously improve the relationship between the parties involved, animals, plants, waters and men, so that in another 100 years continues to exist this interaction with the environment without destroying it. The marketing used by synthetic detergent companies evolved a lot over the years and showed maturity to deal with changes in theories and strategies for promotion and even with the constant social reform that its consumer lived, accompanying them intelligently to be able to capture their changing needs and desires, and so assemble the best way to connect to them. This paper focuses on the subject synthetic detergents as well as (i) types and applications, (ii) threats, (iii) sustainability, (iv) legislation, (v) packaging and (vi) marketing strategies.

  18. Fluorophore Absorption Size Exclusion Chromatography (FA-SEC): An Alternative Method for High-Throughput Detergent Screening of Membrane Proteins.

    PubMed

    Lin, Sung-Yao; Sun, Xing-Han; Hsiao, Yu-Hsuan; Chang, Shao-En; Li, Guan-Syun; Hu, Nien-Jen

    2016-01-01

    Membrane proteins play key roles in many fundamental functions in cells including ATP synthesis, ion and molecule transporter, cell signalling and enzymatic reactions, accounting for ~30% genes of whole genomes. However, the hydrophobic nature of membrane proteins frequently hampers the progress of structure determination. Detergent screening is the critical step in obtaining stable detergent-solubilized membrane proteins and well-diffracting protein crystals. Fluorescence Detection Size Exclusion Chromatography (FSEC) has been developed to monitor the extraction efficiency and monodispersity of membrane proteins in detergent micelles. By tracing the FSEC profiles of GFP-fused membrane proteins, this method significantly enhances the throughput of detergent screening. However, current methods to acquire FSEC profiles require either an in-line fluorescence detector with the SEC equipment or an off-line spectrofluorometer microplate reader. Here, we introduce an alternative method detecting the absorption of GFP (FA-SEC) at 485 nm, thus making this methodology possible on conventional SEC equipment through the in-line absorbance spectrometer. The results demonstrate that absorption is in great correlation with fluorescence of GFP. The comparably weaker absorption signal can be improved by using a longer path-length flow cell. The FA-SEC profiles were congruent with the ones plotted by FSEC, suggesting FA-SEC could be a comparable and economical setup for detergent screening of membrane proteins.

  19. Detergent protease exposure and respiratory disease: case-referent analysis of a retrospective cohort.

    PubMed

    Brant, A; Upchurch, S; van Tongeren, M; Zekveld, C; Helm, J; Barnes, F; Newman Taylor, A J; Cullinan, P

    2009-11-01

    To examine the relationship between protease exposure and respiratory disease in a cohort of detergent enzyme manufacturers. Case-referent analysis of a cohort of employees working in a European detergent factory between 1989 and 2002. Cases with new lower or upper respiratory disease were ascertained by examination of occupational health records and matched to referents on date of first employment. Personal exposures to airborne detergent protease were estimated, using a job exposure matrix, from >12,000 measurements taken in the factory during the period of study. We found clear, monotonic relationships between estimated protease exposure and both lower and upper respiratory disease. After control for age, sex and smoking, the odds ratio of lower respiratory disease was significantly elevated (1.98, 95% CI 1.04 to 3.79) in those employees working in jobs in the highest quartile of protease exposure (geometric mean 7.9 ng x m(-3)). For employees with upper respiratory disease, the risk was significantly elevated at a lower level of estimated protease exposure (geometric mean 2.3 ng x m(-3)). These findings provide strong evidence of an association between detergent enzyme exposure and the development of respiratory disease in an occupational setting. Using the routinely collected information on specific sensitisation and the close attention to workplace exposures that are characteristic of this industry, it should be possible to derive meaningful occupational exposure standards for most detergent enzymes.

  20. Impact of wash cycle time, temperature and detergent formulation on the hygiene effectiveness of domestic laundering.

    PubMed

    Honisch, M; Stamminger, R; Bockmühl, D P

    2014-12-01

    Investigation of the effect of temperature and duration of the laundering process with and without activated oxygen bleach (AOB)-containing detergent on the hygienic effectiveness of laundering. Cotton test swatches were contaminated with Staphylococcus aureus, Enterococcus hirae, Pseudomonas aeruginosa, Candida albicans and Trichophyton mentagrophytes and were washed in a household washing machine using temperatures between 20 and 60°C and different wash cycle times. The logarithmic microbial reduction factor and cross-contamination (i.e. transfer from contaminated to sterile swatches) were used to indicate the hygienic effectiveness of the washing process. For all tested micro-organisms, the temperature needed for decontamination depended on washing time and detergent type. Hygiene effectiveness of laundering was enhanced by inclusion of AOB even at lowest temperatures, except for C. albicans, which was virtually unaffected by AOB. The use of AOB-containing detergents as well as high washing temperatures reduced cross-contamination to sterile swatches included in the load. Depending on the type of organism, longer wash cycle times or the use of AOB-containing detergents can be used to enhance the hygiene effectiveness of laundering. The study demonstrates that it is possible to compensate for the loss of hygiene effectiveness of laundering at lower temperatures using detergents with activated oxygen bleach or by extending the wash cycle time. © 2014 The Society for Applied Microbiology.

  1. Stability of thermostable alkaline protease from Bacillus licheniformis RP1 in commercial solid laundry detergent formulations.

    PubMed

    Sellami-Kamoun, Alya; Haddar, Anissa; Ali, Nedra El-Hadj; Ghorbel-Frikha, Basma; Kanoun, Safia; Nasri, Moncef

    2008-01-01

    The stability of crude extracellular protease produced by Bacillus licheniformis RP1, isolated from polluted water, in various solid laundry detergents was investigated. The enzyme had an optimum pH and temperature at pH 10.0-11.0 and 65-70 degrees C. Enzyme activity was inhibited by PMSF, suggesting that the preparation contains a serine-protease. The alkaline protease showed extreme stability towards non-ionic (5% Tween 20% and 5% Triton X-100) and anionic (0.5% SDS) surfactants, which retained 100% and above 73%, respectively, of its initial activity after preincubation 60 min at 40 degrees C. The RP1 protease showed excellent stability and compatibility with a wide range of commercial solid detergents at temperatures from 40 to 50 degrees C, suggesting its further application in detergent industry. The enzyme retained 95% of its initial activity with Ariel followed by Axion (94%) then Dixan (93.5%) after preincubation 60 min at 40 degrees C in the presence of 7 mg/ml of detergents. In the presence of Nadhif and New Det, the enzyme retained about 83.5% of the original activity. The effects of additives such as maltodextrin, sucrose and PEG 4000 on the stability of the enzyme during spray-drying and during subsequent storage in New Det detergent were also examined. All additives tested enhanced stability of the enzyme.

  2. Characterization of the activity and stability of amylase from saliva and detergent: laboratory practicals for studying the activity and stability of amylase from saliva and various commercial detergents.

    PubMed

    Valls, Cristina; Rojas, Cristina; Pujadas, Gerard; Garcia-Vallve, Santi; Mulero, Miquel

    2012-07-01

    This article presents two integrated laboratory exercises intended to show students the role of α-amylases (AAMYs) in saliva and detergents. These laboratory practicals are based on the determination of the enzymatic activity of amylase from saliva and different detergents using the Phadebas test (quantitative) and the Lugol test (qualitative) under different conditions (e.g. variations in temperature and alkalinity). This work also proposes the study of enzyme stability in the presence of several surfactants and oxidizing agents using the same technical approach. The proposed laboratory exercises promote the understanding of the physiological function of this enzyme and the biotechnological applications of AAMYs in the detergent industry. The exercises also promote the understanding that the enzymatic stability and performance are dependent on the organism of origin, and if necessary, these properties could be modified by genetic engineering. In addition, this article reinforces the development of laboratory skills, problem-solving capabilities, and the ability to write a laboratory report. The exercises are proposed primarily as an undergraduate project for advanced students in the biochemical and biotechnological sciences. These laboratory practicals are complementary to the previously published BAMBED article (Biochemistry and Molecular Biology Education Vol. 39, No. 4, pp. 280-290, 2011) on detergent proteases. Copyright © 2012 Wiley Periodicals, Inc.

  3. Biodegradation of a keratin waste and the concomitant production of detergent stable serine proteases from Paecilomyces lilacinus.

    PubMed

    Cavello, I A; Cavalitto, S F; Hours, R A

    2012-07-01

    Paecilomyces lilacinus (LPS 876) efficiently degraded keratin in chicken feather during submerged cultivation producing extracellular proteases. Characterization of crude protease activity was done including its compatibility in commercial detergents. Optimum pH and temperature were 10.0 and 60 °C, respectively. Protease activity was enhanced by Ca²⁺ but was strongly inhibited by PMSF and by Hg²⁺ suggesting the presence of thiol-dependent serine proteases. The crude protease showed extreme stability toward non-ionic (Tween 20, Tween 85, and Triton X-100) and anionic (SDS) surfactants, and relative stability toward oxidizing agent (H₂O₂ and sodium perborate). In addition, it showed excellent stability and compatibility with various solid and liquid commercial detergents from 30 to 50 °C. The enzyme preparation retained more than 95% of its initial activity with solid detergents (Ariel™ and Drive™) and 97% of its original activity with a liquid detergent (Ace™) after pre-incubation at 40 °C. The protective effect of polyols (propylene glycol, PEG 4000, and glycerol) on the heat inactivation was also examined and the best results were obtained with glycerol from 50 to 60 °C. Considering its promising properties, P. lilacinus enzymatic preparation may be considered as a candidate for use in biotechnological processes (i.e., as detergent additive) and in the processing of keratinous wastes.

  4. Decellularized Rat Lung Scaffolds Using Sodium Lauryl Ether Sulfate for Tissue Engineering.

    PubMed

    Ma, Jinhui; Ju, Zhihai; Yu, Jie; Qiao, Yeru; Hou, Chenwei; Wang, Chen; Hei, Feilong

    Perfusion decellularization with detergents is effective to maintain the architecture and proteins of extracellular matrix (ECM) for use in the field of lung tissue engineering (LTE). However, it is unclear which detergent is ideal to produce an acellular lung scaffold. In this study, we obtained two decellularized rat lung scaffolds using a novel detergent sodium lauryl ether sulfate (SLES) and a conventional detergent sodium dodecyl sulfate (SDS). Both decellularized lung scaffolds were assessed by histology, immunohistochemistry, scanning electron microscopy, DNA quantification, sulfated glycosaminoglycans (GAGs) quantification and western blot. Subsequently, the scaffolds were implanted subcutaneously in rats for 6 weeks and were evaluated via hematoxylin and eosin staining and Masson staining. Results indicated that SLES was effective to remove cells; moreover, lungs decellularized with SLES showed better preservation of sulfated GAGs, lung architecture, and ECM proteins than SDS. After 6 weeks, SLES scaffolds demonstrated a significantly greater potential for cell infiltration and blood vessel formation compared with SDS scaffolds. Taken together, we conclude that SLES is a promising detergent to produce an acellular scaffold using LTE for eventual transplantation.

  5. A comparison of decontamination effects of commercially available detergents in rats pre-exposed to topical sulphur mustard.

    PubMed

    Misik, Jan; Jost, Petr; Pavlikova, Ruzena; Vodakova, Eva; Cabal, Jiri; Kuca, Kamil

    2013-06-01

    The genotoxic vesicant sulphur mustard [bis-2-(chloroethyl)sulphide] is a chemical warfare agent which is easily available due to its relatively simple synthesis. Thus, sulphur mustard is a potential agent for mass contamination. In this study, we focused on sulphur mustard toxicity and decontamination in a rat model using commercially available detergent mixtures for dermal decontamination. Male Wistar rats were percutaneously treated with sulphur mustard and subjected to wet decontamination 2 min postexposure. Commercially produced detergents Neodekont™, Argos™, Dermogel™ and FloraFree™ were tested for their decontamination efficacy against an exposed group and their protective ratios determined. The results showed that all tested detergent solutions produced an increase in the median lethal dose [LD(50) = 9.83 (5.87-13.63) mg·kg(-1)] in comparison to controls, which led to increased survival of experimental animals. In general, all tested detergents provided modest decontamination efficacy (PR = 2.0-5.7). The highest protective ratio (5.7) was consistently achieved with Argos™. Accordingly, Argos™ should be considered in further investigation of mass casualty decontamination.

  6. Dependence of the product chain-length on detergents for long-chain E-polyprenyl diphosphate synthases

    PubMed Central

    Pan, Jian-Jung; Ramamoorthy, Gurusankar; Poulter, C. Dale

    2013-01-01

    Long-chain E-polyprenyl diphosphate synthases (E-PDS) catalyze repetitive addition of isopentenyl diphosphate (IPP) to the growing prenyl chain of an allylic diphosphate. The polyprenyl diphosphate products are required for the biosynthesis of ubiquinones and menaquinones required for electron transport during oxidative phosphorylation to generate ATP. In vitro, the long-chain PDSs require addition of phospholipids or detergents to the assay buffer to enhance product release and maintain efficient turnover. During preliminary assays of product chain-length with anionic, zwitterionic, and non-ionic detergents, we discovered considerable variability. Examination of a series of non-ionic PEG detergents with several long-chain E-PDSs from different organisms revealed that in vitro incubations with nonaethylene glycol monododecyl ether or Triton X-100 typically gave chain lengths that corresponded to those of the isoprenoid moieties in respiratory quinones synthesized in vivo. In contrast incubations in buffer with n-butanol, CHAPS, DMSO, n-octyl-β-glucopyranoside, or β-cyclodextrin or in buffer without detergent typically proceeded more slowly and gave a broad range of chain lengths. PMID:23802587

  7. Development and reduction of hypertension and oxidative stress among detergent industry workers.

    PubMed

    Boojar, Massod M A; Goodarzi, Faranak; Boojar, Manochehr M A

    2004-12-01

    Hypertension status and oxidative stress parameters were assessed in 291 workers (hypertensive workers were divided into three grades, non-equivalently) at two detergent production plants, one of which included enzymes in the detergent (n=138) and another which did not (n=153), and 45 control workers in another industry three times (at the time of employment, 7 yrs later at the time of installation of a filter system, and about 3 yrs later). Malondialdehyde (MDA) was measured by high-performance liquid chromatography, antioxidant enzymes and lipid status by ultraviolet-visible spectrophotometry, trace elements by atomic absorption spectroscopy, and blood pressure using an oscilometric device. Prior to filter system installation, enzyme-exposed workers had significantly higher MDA, antioxidant enzyme activities, and prevalence of hypertension, compared with controls. The filter system reduced airborne detergent and enzyme dusts, resulting in a decreased prevalence of hypertension and a significant improvement in workers' oxidative stress indicators. Alterations in antioxidant status may result from the cumulative effect of high levels of detergent and enzyme in airborne dust in the workplace.

  8. Laundering Your Baby's Clothes

    MedlinePlus

    ... and fragrances that can irritate skin. Note: Cloth diapers do need to be separated from your regular laundry because harsh detergents can cause diaper rash . Wash these with mild baby detergent in ...

  9. Characterization of a Field Portable Raman System for Rapid Chemical Identification

    DTIC Science & Technology

    2007-05-31

    Sodium nitrate, 21% Potassium carbonate, 4% Diethanolamine lauryl sulfate , 2% Methamidophos 3 NMF 4 NMF... Sodium sulfate Y P W P 1 45.3% Detergent, 44.0% Sodium sulfate , 5.7% Benzene 2 44.0% Detergent, 42.6% Sodium sulfate , 7.5% 3- (Ethylamino)toluene 3...47.8% Detergent, 47.6% Sodium sulfate Strontium carbonate N P W P 1 NMF 2 NMF 3 NMF Strontium nitrate N P W P 1 Mixture 79%: 56% Urea nitrate,

  10. Activated-Sludge Nitrification in the Presence of Linear and Branched-Chain Alkyl Benzene Sulfonates

    PubMed Central

    Baillod, Charles R.; Boyle, W. C.

    1968-01-01

    The effects of biodegradable linear alkyl benzene sulfonate and branched-chain alkyl benzene sulfonate detergents on activated-sludge nitrification were investigated by administering a synthetic waste containing up to 23 mg of each detergent per liter to eight bench-scale, batch, activated-sludge units. It was found that both detergents tended to promote complete oxidation of ammonia to nitrate, whereas control units produced approximately equal amounts of nitrite and nitrate. Various hypotheses are offered to explain the phenomenon. PMID:5636474

  11. Detergent-Fearing Milk.

    ERIC Educational Resources Information Center

    Hill, Diane

    1997-01-01

    Describes an activity that demonstrates among the following: diffusion; cohesion and adhesion; properties of surface tension which include wicking, hydrophilic, and hydrophobic molecular behaviors; and break up of fat clusters by liquid dishwashing detergent. (DDR)

  12. Lipid Bilayers in the Gel Phase Become Saturated by Triton X-100 at Lower Surfactant Concentrations Than Those in the Fluid Phase

    PubMed Central

    Ahyayauch, Hasna; Collado, M. Isabel; Alonso, Alicia; Goñi, Felix M.

    2012-01-01

    It has been repeatedly observed that lipid bilayers in the gel phase are solubilized by lower concentrations of Triton X-100, at least within certain temperature ranges, or other nonionic detergents than bilayers in the fluid phase. In a previous study, we showed that detergent partition coefficients into the lipid bilayer were the same for the gel and the fluid phases. In this contribution, turbidity, calorimetry, and 31P-NMR concur in showing that bilayers in the gel state (at least down to 13–20°C below the gel-fluid transition temperature) become saturated with detergent at lower detergent concentrations than those in the fluid state, irrespective of temperature. The different saturation may explain the observed differences in solubilization. PMID:22713566

  13. Removal of detergents from protein extracts using activated charcoal prior to immunological analysis.

    PubMed

    Malhas, Ashraf N; Abuknesha, Ramadan A; Price, Robert G

    2002-06-01

    The use of dextran-coated activated charcoal (DCC) powder to absorb solubilising detergents from cell lysates is described. Normal embryonic epithelial cells were lysed in the presence of sodium dodecyl sulphate (SDS). The detergent was then absorbed with DCC to facilitate analysis of polycystin-1 with antibody-based methods. Polycystin-1 is a membrane protein that is involved in the pathogenesis of autosomal dominant polycystic kidney disease (ADPKD). The adverse effect of SDS on antibody-polycystin-1 binding was studied and the improvement resulting from its removal demonstrated using enzyme-linked immunosorbent assays (ELISAs). The results indicate that DCC can be used in a simple manner to remove highly reactive membrane-solubilising reagents from protein mixtures prior to immunological analysis. This procedure may be relevant to a variety of other techniques that are normally affected by detergents.

  14. Laundry detergent capsules and pediatric poisoning.

    PubMed

    Bonney, Asha G; Mazor, Suzan; Goldman, Ran D

    2013-12-01

    A 4-year-old girl was brought into the emergency department vomiting after having had ingested a laundry detergent capsule (LDC) from under the sink at her house. What is the risk of LDC poisoning? What can be done to treat these children? Laundry detergent capsules are relatively new to supermarket shelves in North America, and there has been an emergence of case reports in the literature describing LDC poisoning, which is worse than poisoning from other laundry detergents. Very little is known about the mechanisms causing these severe reactions, which include airway compromise and esophageal perforation, but the attractive appearance of these capsules and easy access at home has governments and health officials concerned about an increase in poisoning. No residual problems have been associated with these cases to date; however, further research is needed to assess long-term effects.

  15. Assessment of decellularization of heart bioimplants using a Raman spectroscopy method

    NASA Astrophysics Data System (ADS)

    Timchenko, Elena V.; Timchenko, Pavel E.; Lichtenberg, Artur; Assmann, Alexander; Aubin, Hug; Akhyari, Payam; Volova, Larisa T.; Pershutkina, Svetlana V.

    2017-09-01

    We report the results of experimental studies on cardiac implants using a Raman spectroscopy method (RS). Raman spectra characteristics of leaves and walls of cardiac implants were obtained; the implants were manufactured by protocols of detergent-enzymatic technique (DET) and biological, detergent-free (BIO) decellularization, using detergents (group DET) or a detergent-free, nonproteolytic, actin-disassembling regimen (BIO). There were input optical coefficients that allowed us to carry out evaluation of the protocols of DET and BIO decellularization on the basis of the concentrations of glycosaminoglycans, proteins, amides, and DNA. It was shown that during DET and BIO decellularization, composition aberrations of proteins and lipids do not occur and the integrity of the collagenous structures is preserved. It was found that during the DET decellularization, preservation of glycosaminoglycans is better than during BIO decellularization.

  16. A Comparative Study of Rat Lung Decellularization by Chemical Detergents for Lung Tissue Engineering

    PubMed Central

    Tebyanian, Hamid; Karami, Ali; Motavallian, Ebrahim; Aslani, Jafar; Samadikuchaksaraei, Ali; Arjmand, Babak; Nourani, Mohammad Reza

    2017-01-01

    BACKGROUND: Lung disease is the most common cause of death in the world. The last stage of pulmonary diseases is lung transplantation. Limitation and shortage of donor organs cause to appear tissue engineering field. Decellularization is a hope for producing intact ECM in the development of engineered organs. AIM: The goal of the decellularization process is to remove cellular and nuclear material while retaining lung three-dimensional and molecular proteins. Different concentration of detergents was used for finding the best approach in lung decellularization. MATERIAL AND METHODS: In this study, three-time approaches (24, 48 and 96 h) with four detergents (CHAPS, SDS, SDC and Triton X-100) were used for decellularizing rat lungs for maintaining of three-dimensional lung architecture and ECM protein composition which have significant roles in differentiation and migration of stem cells. This comparative study determined that variable decellularization approaches can cause significantly different effects on decellularized lungs. RESULTS: Results showed that destruction was increased with increasing the detergent concentration. Single detergent showed a significant reduction in maintaining of three-dimensional of lung and ECM proteins (Collagen and Elastin). But, the best methods were mixed detergents of SDC and CHAPS in low concentration in 48 and 96 h decellularization. CONCLUSION: Decellularized lung tissue can be used in the laboratory to study various aspects of pulmonary biology and physiology and also, these results can be used in the continued improvement of engineered lung tissue. PMID:29362610

  17. Liposome formation in microgravity.

    PubMed

    Claassen, D E; Spooner, B S

    1996-01-01

    Liposomes are artificial vesicles with a phospholipid bilayer membrane. The formation of liposomes is a self-assembly process that is driven by the amphipathic nature of phospholipid molecules and can be observed during the removal of detergent from phospholipids dissolved in detergent micelles. As detergent concentration in the mixed micelles decreases, the non-polar tail regions of phospholipids produce a hydrophobic effect that drives the micelles to fuse and form planar bilayers in which phospholipids orient with tail regions to the center of the bilayer and polar head regions to the external surface. Remaining detergent molecules shield exposed edges of the bilayer sheet from the aqueous environment. Further removal of detergent leads to intramembrane folding and membrane folding and membrane vesiculation, forming liposomes. We have observed that the formation of liposomes is altered in microgravity. Liposomes that were formed at 1-g did not exceed 150 nm in diameter, whereas liposomes that were formed during spaceflight exhibited diameters up to 2000 nm. Using detergent-stabilized planar bilayers, we determined that the stage of liposome formation most influenced by gravity is membrane vesiculation. In addition, we found that small, equipment-induced fluid disturbances increased vesiculation and negated the size-enhancing effects of microgravity. However, these small disturbances had no effect on liposome size at 1-g, likely due to the presence of gravity-induced buoyancy-driven fluid flows (e.g., convection currents). Our results indicate that fluid disturbances, induced by gravity, influence the vesiculation of membranes and limit the diameter of forming liposomes.

  18. Additive and Synergistic Membrane Permeabilization by Antimicrobial (Lipo)Peptides and Detergents

    PubMed Central

    Patel, Hiren; Huynh, Quang; Bärlehner, Dominik; Heerklotz, Heiko

    2014-01-01

    Certain antibiotic peptides are thought to permeabilize membranes of pathogens by effects that are also observed for simple detergents, such as membrane thinning and disordering, asymmetric bilayer expansion, toroidal pore formation, and micellization. Here we test the hypothesis that such peptides act additively with detergents when applied in parallel. Additivity is defined analogously to a fractional inhibitory concentration index of unity, and the extent and mechanism of leakage is measured by the fluorescence lifetime-based vesicle leakage assay using calcein-loaded vesicles. Good additivity was found for the concerted action of magainin 2, the fungicidal lipopeptide class of surfactins from Bacillus subtilis QST713, and the detergent octyl glucoside, respectively, with the detergent C12EO8. Synergistic or superadditive action was observed for fengycins from B. subtilis, as well as the detergent CHAPS, when combined with C12EO8. The results illustrate two mechanisms of synergistic action: First, maximal leakage requires an optimum degree of heterogeneity in the system that may be achieved by mixing a graded with an all-or-none permeabilizer. (The optimal perturbation should be focused to certain defect structures, yet not to the extent that some vesicles are not affected at all.) Second, a cosurfactant may enhance the bioavailability of a poorly soluble peptide. The results are important for understanding the concerted action of membrane-permeabilizing compounds in biology as well as for optimizing formulations of such antimicrobials for medical applications or crop protection. PMID:24853740

  19. Liposome formation in microgravity

    NASA Astrophysics Data System (ADS)

    Claassen, D. E.; Spooner, B. S.

    Liposomes are artificial vesicles with a phospholipid bilayer membrane. The formation of liposomes is a self-assembly process that is driven by the amphipathic nature of phospholipid molecules and can be observed during the removal of detergent from phospholipids dissolved in detergent micelles. As detergent concentration in the mixed micelles decreases, the non-polar tail regions of phospholipids produce a hydrophobic effect that drives the micelles to fuse and form planar bilayers in which phospholipids orient with tail regions to the center of the bilayer and polar head regions to the external surface. Remaining detergent molecules shield exposed edges of the bilayer sheet from the aqueous environment. Further removal of detergent leads to intramembrane folding and membrane vesiculation, forming liposomes. We have observed that the formation of liposomes is altered in microgravity. Liposomes that were formed at 1-g did not exceed 150 nm in diameter, whereas liposomes that were formed during spaceflight exhibited diameters up to 2000 nm. Using detergent-stabilized planar bilayers, we determined that the stage of liposome formation most influenced by gravity is membrane vesiculation. In addition, we found that small, equipment-induced fluid disturbances increased vesiculation and negated the size-enhancing effects of microgravity. However, these small disturbances had no effect on liposome size at 1-g, likely due to the presence of gravity-induced buoyancy-driven fluid flows (e.g., convection currents). Our results indicate that fluid disturbances, induced by gravity, influence the vesiculation of membranes and limit the diameter of forming liposomes.

  20. Sodium hydroxide based non-detergent decellularizing solution for rat lung.

    PubMed

    Sengyoku, Hideyori; Tsuchiya, Tomoshi; Obata, Tomohiro; Doi, Ryoichiro; Hashimoto, Yasumasa; Ishii, Mitsutoshi; Sakai, Hiromi; Matsuo, Naoto; Taniguchi, Daisuke; Suematsu, Takashi; Lawn, Murray; Matsumoto, Keitaro; Miyazaki, Takuro; Nagayasu, Takeshi

    2018-06-11

    Lung transplantation is the last option for the treatment of end stage chronic lung disorders. Because the shortage of donor lung organs represents the main hurdle, lung regeneration has been considered to overcome this hurdle. Recellularization of decellularized organ scaffold is a promising option for organ regeneration. Although detergents are ordinarily used for decellularization, other approaches are possible. Here we used high alkaline (pH12) sodium hydroxide (NaOH)-PBS solution without detergents for lung decellularization and compared the efficacy on DNA elimination and ECM preservation with detergent based decellularization solutions CHAPS and SDS. Immunohistochemical image analysis showed that cell components were removed by NaOH solution as well as other detergents. A Collagen and GAG assay showed that the collagen reduction of the NaOH group was comparable to that of the CHAPS and SDS groups. However, DNA reduction was more significant in the NaOH group than in other groups (p < 0.0001). The recellularization of HUVEC revealed cell attachment was not inferior to that of the SDS group. Ex vivo functional analysis showed 100% oxygen ventilation increased oxygen partial pressure as artificial hemoglobin vesicle-PBS solution passed through regenerated lungs in the SDS or NaOH group. It was concluded that the NaOH-PBS based decellularization solution was comparable to ordinal decellularizaton solutions and competitive in cost effectiveness and residues in the decellularized scaffold negligible, thus providing another potential option to detergent for future clinical usage.

  1. Micro-scale NMR Experiments for Monitoring the Optimization of Membrane Protein Solutions for Structural Biology.

    PubMed

    Horst, Reto; Wüthrich, Kurt

    2015-07-20

    Reconstitution of integral membrane proteins (IMP) in aqueous solutions of detergent micelles has been extensively used in structural biology, using either X-ray crystallography or NMR in solution. Further progress could be achieved by establishing a rational basis for the selection of detergent and buffer conditions, since the stringent bottleneck that slows down the structural biology of IMPs is the preparation of diffracting crystals or concentrated solutions of stable isotope labeled IMPs. Here, we describe procedures to monitor the quality of aqueous solutions of [ 2 H, 15 N]-labeled IMPs reconstituted in detergent micelles. This approach has been developed for studies of β-barrel IMPs, where it was successfully applied for numerous NMR structure determinations, and it has also been adapted for use with α-helical IMPs, in particular GPCRs, in guiding crystallization trials and optimizing samples for NMR studies (Horst et al ., 2013). 2D [ 15 N, 1 H]-correlation maps are used as "fingerprints" to assess the foldedness of the IMP in solution. For promising samples, these "inexpensive" data are then supplemented with measurements of the translational and rotational diffusion coefficients, which give information on the shape and size of the IMP/detergent mixed micelles. Using microcoil equipment for these NMR experiments enables data collection with only micrograms of protein and detergent. This makes serial screens of variable solution conditions viable, enabling the optimization of parameters such as the detergent concentration, sample temperature, pH and the composition of the buffer.

  2. Effects of detergents on ribosomal precursor subunits of Bacillus megaterium.

    PubMed

    Body, A; Brownstein, B H

    1978-01-01

    Cell extracts prepared by osmotic lysis of protoplasts were analyzed by sucrose gradient sedimentation. In the absence of detergents, ribosomal precursor particles were found in a gradient fraction which sedimented faster than mature 50S subunits and in two other fractions coincident with mature 50S and 30S ribosomal subunits. Phospholipid, an indicator of membrane, was shown to be associated with only the fastest-sedimenting ribosomal precursor particle fraction. After the extracts were treated with detergents, all phospholipid was found at the top of the gradients. Brij 58, Triton X-100, and Nonidet P-40 did not cause a change in the sedimentation values of precursors; however, the detergents deoxycholate or LOC (Amway Corp.) disrupted the fastest-sedimenting precursor and converted the ribosomal precursor subunits which sedimented at the 50S and 30S positions to five different classes of more slowly sedimenting particles. Earlier reports on the in vivo assembly of ribosomal subunits have shown that several stages of ribosomal precursor subunits exist, and, in the presence of the detergents deoxycholate and LOC, which had been used to prepare cell extracts, the precursors sedimented more slowly. Our data are consistent with the hypothesis that those detergents selectively modify the structure of ribosomal precursors and lend further support to the hypothesis that the in vivo ribosomal precursor subunits have 50S and 30S sedimentation values. In addition, these data support the idea that the ribosomal precursor particles found in the fast-sedimenting fraction may constitute a unique precursor fraction.

  3. Effects of Detergents on Ribosomal Precursor Subunits of Bacillus megaterium

    PubMed Central

    Body, Barbara A.; Brownstein, Bernard H.

    1978-01-01

    Cell extracts prepared by osmotic lysis of protoplasts were analyzed by sucrose gradient sedimentation. In the absence of detergents, ribosomal precursor particles were found in a gradient fraction which sedimented faster than mature 50S subunits and in two other fractions coincident with mature 50S and 30S ribosomal subunits. Phospholipid, an indicator of membrane, was shown to be associated with only the fastest-sedimenting ribosomal precursor particle fraction. After the extracts were treated with detergents, all phospholipid was found at the top of the gradients. Brij 58, Triton X-100, and Nonidet P-40 did not cause a change in the sedimentation values of precursors; however, the detergents deoxycholate or LOC (Amway Corp.) disrupted the fastest-sedimenting precursor and converted the ribosomal precursor subunits which sedimented at the 50S and 30S positions to five different classes of more slowly sedimenting particles. Earlier reports on the in vivo assembly of ribosomal subunits have shown that several stages of ribosomal precursor subunits exist, and, in the presence of the detergents deoxycholate and LOC, which had been used to prepare cell extracts, the precursors sedimented more slowly. Our data are consistent with the hypothesis that those detergents selectively modify the structure of ribosomal precursors and lend further support to the hypothesis that the in vivo ribosomal precursor subunits have 50S and 30S sedimentation values. In addition, these data support the idea that the ribosomal precursor particles found in the fast-sedimenting fraction may constitute a unique precursor fraction. PMID:412833

  4. Killing of preimplantation mouse embryos by main ingredients of cleansers AS and LAS.

    PubMed

    Nomura, T; Hata, S; Shibata, K; Kusafuka, T

    1987-01-01

    When main ingredients of cleansers, alcohol sulfate (AS) and linear alkylbenzene sulfonate (LAS), were applied to the dorsal skin of pregnant JCL:ICR mice during preimplantation period (days 0-2), significant numbers of embryos collected from the oviducts and uteri on day 3 showed severe deformity or remained at the morula stage. Most of abnormal embryos were fragmented or remained at the 1-8 cell stages, and they were either dead or dying. Even when these abnormal embryos were cultivated in the detergent-free medium, they were not recovered, while most growth-retarded embryos (morula) could grow and hatch with one or two days lag by the further in vitro cultivation. Similar results were observed with commercially obtained kitchen detergent and hair shampoo, although such embryocidal effects were not detected with natural soap and distilled water. Fertilized eggs may be specifically sensitive to synthetic detergents. Very low doses of X-rays also induced significant yields of abnormal embryos. Major difference between X-rays and detergents was that X-ray-induced abnormality appeared at the morula or blastocyst stage, while detergent-induced one did at the earlier stages.

  5. Maximizing detergent stability and functional expression of a GPCR by exhaustive recombination and evolution.

    PubMed

    Schlinkmann, Karola M; Hillenbrand, Matthias; Rittner, Alexander; Künz, Madeleine; Strohner, Ralf; Plückthun, Andreas

    2012-09-21

    To identify structural features in a G-protein-coupled receptor (GPCR) crucial for biosynthesis, stability in the membrane and stability in detergent micelles, we developed an evolutionary approach using expression in the inner membrane of Escherichia coli. From the analysis of 800,000 sequences of the rat neurotensin receptor 1, in which every amino acid had been varied to all 64 codons, we uncovered several "shift" positions, where the selected population focuses on a residue different from wild type. Here, we employed in vitro DNA recombination and a comprehensive synthetic binary library made by the Slonomics® technology, allowing us to uncover additive and synergistic effects in the structure that maximize both detergent stability and functional expression. We identified variants with >25,000 functional molecules per E. coli cell, a 50-fold increase over wild type, and observed strong coevolution of detergent stability. We arrived at receptor variants highly stable in short-chain detergents, much more so than those found by alanine scanning on the same receptor. These evolved GPCRs continue to be able to signal through the G-protein. We discuss the structural reasons for these improvements achieved through directed evolution. Copyright © 2012 Elsevier Ltd. All rights reserved.

  6. Diesel fuel detergent additive performance and assessment

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Vincent, M.W.; Papachristos, M.J.; Williams, D.

    Diesel fuel detergent additives are increasingly linked with high quality automotive diesel fuels. Both in Europe and in the USA, field problems associated with fuel injector coking or fouling have been experienced. In Europe indirect injection (IDI) light duty engines used in passenger cars were affected, while in the USA, a direct injection (DI) engine in heavy duty truck applications experienced field problems. In both cases, a fuel additive detergent performance test has evolved using an engine linked with the original field problem, although engine design modifications employed by the manufacturers have ensured improved operation in service. Increasing awareness ofmore » the potential for injector nozzle coking to cause deterioration in engine performance is coupled with a need to meet ever more stringent exhaust emissions legislation. These two requirements indicate that the use of detergency additives will continue to be associated with high quality diesel fuels. The paper examines detergency performance evaluated in a range of IDI and DI engines and correlates performance in the two most widely recognised test engines, namely the Peugeot 1.9 litre IDI, and Cummins L10 DI engines. 17 refs., 18 figs., 5 tabs.« less

  7. Foam Properties and Detergent Abilities of the Saponins from Camellia oleifera

    PubMed Central

    Chen, Yu-Fen; Yang, Chao-Hsun; Chang, Ming-Shiang; Ciou, Yong-Ping; Huang, Yu-Chun

    2010-01-01

    The defatted seed meal of Camellia oleifera has been used as a natural detergent and its extract is commercially utilized as a foam-stabilizing and emulsifying agent. The goal of this study was to investigate the foam properties and detergent ability of the saponins from the defatted seed meal of C. oleifera. The crude saponin content in the defatted seed meal of C. oleifera was 8.34 and the total saponins content in the crude saponins extract was 39.5% (w/w). The foaming power of the 0.5 crude saponins extract solution from defatted seed meal of C. oleifera was 37.1 of 0.5 SLS solution and 51.3% to that of 0.5% Tween 80 solution. The R5 value of 86.0% represents good foam stability of the crude saponins extracted from the defatted seed meal of the plant. With the reduction of water surface tension from 72 mN/m to 50.0 mN/m, the 0.5% crude saponins extract solution has wetting ability. The sebum-removal experiment indicated that the crude saponins extract has moderate detergency. The detergent abilities of the saponins from C. oleifera and Sapindus mukorossi were also compared. PMID:21151446

  8. Respiratory symptoms and peak expiratory flow rates in workers of a Nigerian soap and detergent industry.

    PubMed

    Bamidele, J O

    2002-01-01

    This comparative cross-sectional study was carried out to assess the respiratory symptoms and peak expiratory flow rates of the factory(study group) and office(control group) workers in a soap and detergent industry in Ilorin in relation to the occupational hazards of chemical fumes and detergent dust in the industry. Upper respiratory tract infections were found in 67.5% and 10.6% of the study group and control group respectively. The study shows that the factory workers experienced hazards (e.g. chemical fumes and detergent dust) at work more than the office workers. Personal protective devices such as boots, face masks, gloves, earmuffs and goggles were not consistently used since they were inadequate in supply, worn out and of substandard qualities. The general reduction in the mean values of peak expiratory flow rate in the factory workers than in the office workers as observed in this study may possibly, be a pointer to the effect of industrial exposure to chemical fumes and detergent dust over the years. There is the need to follow up these workers in order to detect early any possible disease and complications that may arise.

  9. Inclusion of detergent in a cleaning regime and effect on microbial load in livestock housing.

    PubMed

    Hancox, L R; Le Bon, M; Dodd, C E R; Mellits, K H

    Determining effective cleaning and disinfection regimes of livestock housing is vital to improving the health of resident animals and reducing zoonotic disease. A cleaning regime consisting of scraping, soaking with or without detergent (treatment and control), pressure washing, disinfection and natural drying was applied to multiple pig pens. After each cleaning stage, samples were taken from different materials and enumerated for total aerobic count (TAC) and Enterobacteriaceae (ENT). Soaking with detergent (Blast-Off, Biolink) caused significantly greater reductions of TAC and ENT on metal, and TAC on concrete, compared with control. Disinfection effect (Virkon S, DuPont) was not significantly associated with prior detergent treatment. Disinfection significantly reduced TAC and ENT on concrete and stock board but not on metal. Twenty-four hours after disinfection TAC and ENT on metal and stock board were significantly reduced, but no significant reductions occurred in the subsequent 96 hours. Counts on concrete did not significantly reduce during the entire drying period (120 hours). Detergent and disinfectant have varying bactericidal effects according to the surface and bacterial target; however, both can significantly reduce microbial numbers so should be used during cleaning, with a minimum drying period of 24 hours, to lower bacterial counts effectively.

  10. Methylisothiazolinone in selected consumer products in Belgium: Adding fuel to the fire?

    PubMed

    Aerts, Olivier; Meert, Hans; Goossens, An; Janssens, Sighile; Lambert, Julien; Apers, Sandra

    2015-09-01

    Methylisothiazolinone (MI) contact allergy is severely affecting consumers with allergic contact dermatitis, owing to its presence in cosmetics, household detergents, and water-based paints, in particular. Data on the true isothiazolinone concentrations in these products are scarce, and labelling may be incorrect. To report on the MI concentrations in such products marketed in Belgium, in order to verify the accuracy of labelling (when applicable) and compliance with EU regulations. Thirty cosmetics (18 leave-on and 12 rinse-off), eight detergents and four paints were analysed for MI by the use of high-performance liquid chromatography with ultraviolet detection. The analysed leave-on, and to a lesser extent the rinse-off, cosmetics, contained MI at concentrations far exceeding the permitted 100 ppm use concentration. Household detergents contained high concentrations of MI, and mislabelling occurred for both cosmetics and detergents. The (limited) data on paints are in line with the existing literature. Cosmetics and detergents may facilitate contact sensitization because of a (too) high MI concentration, and mislabelling may make its avoidance extremely difficult. Safer use concentrations and correct labelling should be ensured by adequate quality control. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  11. Advanced Exploration Systems (AES) Logistics Reduction Project: Crew Clothing Care Process Development. Revision: Basic

    NASA Technical Reports Server (NTRS)

    Demmler, Morgan; Whitehead, Nickolas; Poritz, Darwin; Orndoff, Evelyne

    2017-01-01

    This report covers the use of ozone and mist with detergent to develop zero-gravity laundering technology. Different concentrations of detergent with and without ozone were applied to remove odor from t-shirts used during exercise. The fabrics of these shirts were categorized into two groups: hydrophobic (polyester and modacrylic) and hydrophilic (cotton and Merino wool). It was found that applying detergent solution as a mist sufficient to achieve saturation can be effective in eliminating odors from athletically soiled shirts either with or without exposure to ozone.

  12. Preliminary characterization of Thy-1.1 and Ag-B antigens from rat tissues solubilized in detergents

    PubMed Central

    Letarte-Muirhead, Michelle; Acton, Ronald T.; Williams, Alan F.

    1974-01-01

    1. A radioactive binding assay for Thy-1.1 alloantigen which functions in the presence of detergents was established by using glutaraldehyde-fixed thymocytes as target cells. Thy-1.1 activity in detergent extracts was then assayed by measuring inhibition of the binding assay. 2. Solubilization of Thy-1.1 from whole thymocytes, and their membranes by a large number of non-ionic detergents and deoxycholate was studied. In the same extracts Ag-B(4) histocompatibility antigenic activities were measured. With the exception of Nonidet P-40, the detergents did not affect the antigenicity of Thy-1.1, but only Lubrol-PX and deoxycholate gave effective solubilization as measured by activity remaining in the supernatant after centrifugation at 200000g for 40min. With Ag-B(4) antigen, Triton X-100, Triton X-67 and Nonidet P-40 gave effective solubilization as well as Lubrol-PX and deoxycholate. Solubilization of Thy-1.1 activity from leukaemia cells and a brain homogenate was also studied, but none of the non-ionic detergents gave satisfactory results with these tissues. 3. Extracts from thymocyte membranes were further examined by gel filtration and sucrose gradient centrifugation. The Thy-1.1 activity behaved as a single component in deoxycholate with a density similar to that of a globular protein, but in Lubrol-PX the antigen was contained in a low-density complex. In Lubrol-PX extracts Ag-B(4) was also found in aggregates not observed in deoxycholate. 4. The s20,w values for Thy-1.1 and Ag-B(4) antigens in deoxycholate were 2.4 and 4.4, and v̄ values were 0.70 and 0.75 respectively. The Stokes radius observed for Thy-1.1 was 3.1nm and for Ag-B(4) 5.3nm. By using these values the molecular weights for the antigen–detergent complexes were calculated to be 28000 for Thy-1.1 and 100000 for Ag-B(4). PMID:4219284

  13. Dirt-binding particles consisting of hydrogenated castor oil beads constitute a nonirritating alternative for abrasive cleaning of recalcitrant oily skin contamination in a three-step programme of occupational skin protection.

    PubMed

    Mahler, V; Erfurt-Berge, C; Schiemann, S; Michael, S; Egloffstein, A; Kuss, O

    2010-04-01

    In occupational fields with exposure to grease, oil, metal particles, coal, black lead or soot, cleansing formulations containing abrasive bodies (e.g. refined walnut shell, corn, wood, plastic or pumice) are used. These may constitute an irritant per se. As an alternative, hydrogenated castor oil (also known as castor wax) beads have been developed as dirt-binding particles. A polar surface contributes to their mechanical cleaning effects in removal of oily grime. Standardized examination of the in vivo effects upon the skin barrier of castor wax beads in comparison with abrasive bodies and pure detergent. Three cleansing preparations - (i) detergent, (ii) detergent containing castor wax beads, (iii) detergent containing walnut shell powder - were each repetitively applied in vivo (four times daily for 3 weeks), mimicking workplace conditions, in 30 healthy volunteers (15 with and 15 without an atopic skin diathesis) and compared vs. (iv) no treatment. The treatment effects upon the skin barrier were monitored by repeated measurements of functional parameters [transepidermal water loss (TEWL), redness] and surface topography. After a 3-week treatment, a significant global treatment effect (P < 0.0001) was found in the atopic group concerning TEWL as indicator for barrier function. A significantly higher TEWL and increasing erythema in the area treated with detergent containing walnut shell powder reflected its irritant effect compared with castor wax beads dispensed in the identical detergent. Cleaning properties of the two formulas were comparably superior to detergent alone. Castor wax beads constitute a novel nonirritating alternative for abrasive cleaning of recalcitrant oily skin contamination appropriate for individuals with an atopic skin diathesis in a three-step programme of occupational skin protection. As the skin barrier may additionally be influenced by the composition of dirt and use of skin protection and skin care measures under real workplace conditions, this component may now be used and examined further in different occupations.

  14. Reduction of ultraviolet transmission through cotton T-shirt fabrics with low ultraviolet protection by various laundering methods and dyeing: clinical implications.

    PubMed

    Wang, S Q; Kopf, A W; Marx, J; Bogdan, A; Polsky, D; Bart, R S

    2001-05-01

    The public has long been instructed to wear protective clothing against ultraviolet (UV) damage. Our purpose was to determine the UV protection factor (UPF) of two cotton fabrics used in the manufacture of summer T-shirts and to explore methods that could improve the UPF of these fabrics. Each of the two types of white cotton fabrics (cotton T-shirt and mercerized cotton print cloth) used in this study was divided into 4 treatment groups: (1) water-only (machine washed with water), (2) detergent-only (washed with detergent), (3) detergent-UV absorber (washed with detergent and a UV absorber), and (4) dyes (dyed fabrics). Ultraviolet transmission through the fabrics was measured with a spectrophotometer before and after laundry and dyeing treatments. Based on UV transmission through these fabrics, the UPF values were calculated. Before any treatments, the mean UPFs were 4.94 for the T-shirt fabric and 3.13 for the print cloth. There was greater UVA (320-400 nm) than UVB (280-320 nm) transmission through these fabrics. After 5 washings with water alone and with detergent alone, UPF increased by 51% and 17%, respectively, for the cotton T-shirt fabric. Washing the T-shirt fabrics with detergent plus the UV-absorbing agent increased the UPF by 407% after 5 treatments. Dyeing the fabric blue or yellow increased the UPF by 544% and 212%, respectively. Similar changes in UPFs were observed for the print cloth fabric. The two cotton fabrics used in this study offered limited protection against UV radiation as determined by spectrophotometric analysis. Laundering with detergent and water improves UPF slightly by causing fabric shrinkage. Dyeing fabrics or adding a UV-absorbing agent during laundering substantially reduces UV transmission and increases UPF. More UVA is transmitted through the fabrics than UVB.

  15. The effects of non-ionic polymeric surfactants on the cleaning of biofouled hydrogel materials.

    PubMed

    Guan, Allan; Li, Zhenyu; Phillips, K Scott

    2015-01-01

    Block co-polymer surfactants have been used for cleaning hydrogel medical devices that contact the body (e.g., contact lenses) because of their biocompatibility. This work examined the relationship between concentration and detergency of two non-ionic polymeric surfactants (Pluronic F127 and Triton X-100) for cleaning protein soil, with anionic surfactants (sodium dodecyl sulfate and sodium laureth sulfate) as positive controls. Surface plasmon resonance was used to quantify removal of simulated tear soil from self-assembled monolayer surfaces, and a microplate format was used to study the removal of fluorescently labeled soil proteins from contact lenses. While detergency increased as a function of concentration for anionic surfactants, it decreased with concentration for the two polymeric surfactants. The fact that the protein detergency of some non-ionic polymeric surfactants did not increase with concentration above the critical micelle concentration could have implications for optimizing the tradeoff between detergency and biocompatibility.

  16. Correlative microscopy of detergent granules.

    PubMed

    van Dalen, G; Nootenboom, P; Heussen, P C M

    2011-03-01

    The microstructure of detergent products for textile cleaning determines to a large extent the physical properties of these products. Correlative microscopy was used to reveal the microstructure by reconciling images obtained by scanning electron microscopy with energy dispersive X-ray analysis, X-ray microtomography and Fourier transform infrared microscopy. These techniques were applied on the same location of a subsample of a spray-dried detergent base powder embedded in polyacrylate. In this way, the three-dimensional internal and external structure of detergent granules could be investigated from milli to nano scale with detailed spatial information about the components present. This will generate knowledge how to design optimal microstructures for laundry products to obtain product properties demanded by the market. This method is also very useful for other powder systems used in a large variety of industries (e.g. for pharmaceutical, food, ceramic and metal industries). © 2010 The Authors Journal of Microscopy © 2010 The Royal Microscopical Society.

  17. Lidocaine effect on flotillin-2 distribution in detergent-resistant membranes of equine jejunal smooth muscle in vitro.

    PubMed

    Tappenbeck, Karen; Schmidt, Sonja; Feige, Karsten; Naim, Hassan Y; Huber, Korinna

    2014-05-01

    Lidocaine is the most commonly chosen prokinetic for treating postoperative ileus in horses, a motility disorder associated with ischaemia-reperfusion injury of intestinal tissues. Despite the frequent use of lidocaine, the mechanism underlying its prokinetic effects is still unclear. Previous studies suggested that lidocaine altered cell membrane characteristics of smooth muscle cells. Therefore, the present study aimed to elucidate effects of lidocaine administration on characteristics of detergent-resistant membranes in equine jejunal smooth muscle. Lidocaine administration caused significant redistribution of flotillin-2, a protein marker of detergent-resistant membranes, in fractions of sucrose-density-gradients obtained from ischaemia-reperfusion injured smooth muscle solubilised with Triton X-100. It was concluded that lidocaine induced disruption of detergent-resistant membranes which might affect ion channel activity and therefore enhance smooth muscle contractility. Copyright © 2014 Elsevier Ltd. All rights reserved.

  18. Laundry detergent capsules and pediatric poisoning

    PubMed Central

    Bonney, Asha G.; Mazor, Suzan; Goldman, Ran D.

    2013-01-01

    Abstract Question A 4-year-old girl was brought into the emergency department vomiting after having had ingested a laundry detergent capsule (LDC) from under the sink at her house. What is the risk of LDC poisoning? What can be done to treat these children? Answer Laundry detergent capsules are relatively new to supermarket shelves in North America, and there has been an emergence of case reports in the literature describing LDC poisoning, which is worse than poisoning from other laundry detergents. Very little is known about the mechanisms causing these severe reactions, which include airway compromise and esophageal perforation, but the attractive appearance of these capsules and easy access at home has governments and health officials concerned about an increase in poisoning. No residual problems have been associated with these cases to date; however, further research is needed to assess long-term effects. PMID:24336541

  19. Role of Detergents in Conformational Exchange of a G Protein-coupled Receptor*

    PubMed Central

    Chung, Ka Young; Kim, Tae Hun; Manglik, Aashish; Alvares, Rohan; Kobilka, Brian K.; Prosser, R. Scott

    2012-01-01

    The G protein-coupled β2-adrenoreceptor (β2AR) signals through the heterotrimeric G proteins Gs and Gi and β-arrestin. As such, the energy landscape of β2AR-excited state conformers is expected to be complex. Upon tagging Cys-265 of β2AR with a trifluoromethyl probe, 19F NMR was used to assess conformations and possible equilibria between states. Here, we report key differences in β2AR conformational dynamics associated with the detergents used to stabilize the receptor. In dodecyl maltoside (DDM) micelles, the spectra are well represented by a single Lorentzian line that shifts progressively downfield with activation by appropriate ligand. The results are consistent with interconversion between two or more states on a time scale faster than the greatest difference in ligand-dependent chemical shift (i.e. >100 Hz). Given that high detergent off-rates of DDM monomers may facilitate conformational exchange between functional states of β2AR, we utilized the recently developed maltose-neopentyl glycol (MNG-3) diacyl detergent. In MNG-3 micelles, spectra indicated at least three distinct states, the relative populations of which depended on ligand, whereas no ligand-dependent shifts were observed, consistent with the slow exchange limit. Thus, detergent has a profound effect on the equilibrium kinetics between functional states. MNG-3, which has a critical micelle concentration in the nanomolar regime, exhibits an off-rate that is 4 orders of magnitude lower than that of DDM. High detergent off-rates are more likely to facilitate conformational exchange between distinct functional states associated with the G protein-coupled receptor. PMID:22893704

  20. Detergent-free purification of ABC (ATP-binding-cassette) transporters.

    PubMed

    Gulati, Sonali; Jamshad, Mohammed; Knowles, Timothy J; Morrison, Kerrie A; Downing, Rebecca; Cant, Natasha; Collins, Richard; Koenderink, Jan B; Ford, Robert C; Overduin, Michael; Kerr, Ian D; Dafforn, Timothy R; Rothnie, Alice J

    2014-07-15

    ABC (ATP-binding-cassette) transporters carry out many vital functions and are involved in numerous diseases, but study of the structure and function of these proteins is often hampered by their large size and membrane location. Membrane protein purification usually utilizes detergents to solubilize the protein from the membrane, effectively removing it from its native lipid environment. Subsequently, lipids have to be added back and detergent removed to reconstitute the protein into a lipid bilayer. In the present study, we present the application of a new methodology for the extraction and purification of ABC transporters without the use of detergent, instead, using a copolymer, SMA (polystyrene-co-maleic acid). SMA inserts into a bilayer and assembles into discrete particles, essentially solubilizing the membrane into small discs of bilayer encircled by a polymer, termed SMALPs (SMA lipid particles). We show that this polymer can extract several eukaryotic ABC transporters, P-glycoprotein (ABCB1), MRP1 (multidrug-resistance protein 1; ABCC1), MRP4 (ABCC4), ABCG2 and CFTR (cystic fibrosis transmembrane conductance regulator; ABCC7), from a range of different expression systems. The SMALP-encapsulated ABC transporters can be purified by affinity chromatography, and are able to bind ligands comparably with those in native membranes or detergent micelles. A greater degree of purity and enhanced stability is seen compared with detergent solubilization. The present study demonstrates that eukaryotic ABC transporters can be extracted and purified without ever being removed from their lipid bilayer environment, opening up a wide range of possibilities for the future study of their structure and function.

  1. Detergent-dependent kinetics of truncated Plasmodium falciparum dihydroorotate dehydrogenase.

    PubMed

    Malmquist, Nicholas A; Baldwin, Jeffrey; Phillips, Margaret A

    2007-04-27

    The survival of the malaria parasite Plasmodium falciparum is dependent upon the de novo biosynthesis of pyrimidines. P. falciparum dihydroorotate dehydrogenase (PfDHODH) catalyzes the fourth step in this pathway in an FMN-dependent reaction. The full-length enzyme is associated with the inner mitochondrial membrane, where ubiquinone (CoQ) serves as the terminal electron acceptor. The lipophilic nature of the co-substrate suggests that electron transfer to CoQ occurs at the two-dimensional lipid-solution interface. Here we show that PfDHODH associates with liposomes even in the absence of the N-terminal transmembrane-spanning domain. The association of a series of ubiquinone substrates with detergent micelles was studied by isothermal titration calorimetry, and the data reveal that CoQ analogs with long decyl (CoQ(D)) or geranyl (CoQ(2)) tails partition into detergent micelles, whereas that with a short prenyl tail (CoQ(1)) remains in solution. PfDHODH-catalyzed reduction of CoQ(D) and CoQ(2), but not CoQ(1), is stimulated as detergent concentrations (Tween 80 or Triton X-100) are increased up to their critical micelle concentrations, beyond which activity declines. Steady-state kinetic data acquired for the reaction with CoQ(D) and CoQ(2) in substrate-detergent mixed micelles fit well to a surface dilution kinetic model. In contrast, the data for CoQ(1) as a substrate were well described by solution steady-state kinetics. Our results suggest that the partitioning of lipophilic ubiquinone analogues into detergent micelles needs to be an important consideration in the kinetic analysis of enzymes that utilize these substrates.

  2. Development of USEtox characterisation factors for dishwasher detergents using data made available under REACH.

    PubMed

    Igos, Elorri; Moeller, Ruth; Benetto, Enrico; Biwer, Arno; Guiton, Mélanie; Dieumegard, Philippe

    2014-04-01

    Because of the more and more stringent regulations and customer demand, dishwasher detergent manufacturers are constantly improving the composition of the products towards better environmental performances. In order to quantify the pros and cons of these changes on the lifecycle of detergents, as compared to conventional products, the use of Life Cycle Assessment (LCA) is a meaningful opportunity. However, the application of the methodology is hampered by the lack of Characterisation Factors (CFs) relative to the specific chemical substances included in the detergents composition, which cannot be included in the impact assessment of the effluent discharge. In this study we have tackled this problem, taking advantage of the specific case of three dishwasher detergents produced by the Chemolux/McBride group: phosphate-based, eco-labelled and phosphate-free formulations. Nine CFs for freshwater ecotoxicity and seven CFs for human toxicity have been developed, using the USEtox methodology and data made available under the REACH regulation. As a result, the dishwasher effluent composition could be characterised by more than 95% for freshwater ecotoxicity whereas for human toxicity the percentage was less than 36%, due to the lack of adequate and reliable repeated dose toxicity studies. The main contributing substances to freshwater ecotoxicity were found to be sodium percarbonate and sodium triphosphate, the latter confirming the pertinence of phosphates banning in the detergent industry. Regarding human toxicity, zinc shows the highest contribution. Further comparison to previous studies and sensitivity analysis substantiated the robustness of these conclusions. Copyright © 2013 Elsevier Ltd. All rights reserved.

  3. Toxicity assessment of a common laundry detergent using the freshwater flagellate Euglena gracilis.

    PubMed

    Azizullah, Azizullah; Richter, Peter; Häder, Donat-Peter

    2011-09-01

    Synthetic detergents are among the commonly used chemicals in everyday life. Detergents, reaching aquatic environments through domestic and municipal wastewater, can cause many different effects in aquatic organisms. The present study was aimed at the toxicity evaluation of a commonly used laundry detergent, Ariel, using the freshwater flagellate Euglena gracilis as a biotest organism. Different parameters of the flagellate like motility, swimming velocity, cell shape, gravitactic orientation, photosynthesis and concentration of light harvesting pigments were used as end points for the toxicity assessment. No Observed Effect Concentration (NOEC) and EC(50) values were calculated for the end point parameters at four different incubation times, i.e. 0, 6, 24 and 72 h. After 72 h incubation, swimming velocity of the cells was found to be the most sensitive parameter giving NOEC and EC(50) values of 10.8 and 34 mg L(-1), respectively. After 72 h exposure to the detergent, chlorophyll a and total carotenoids were significantly decreased in cultures treated with Ariel at concentrations of 50 mg L(-1) and above while chlorophyll b significantly decreased at concentrations above 750 mg L(-1). The maximum inhibitory effect on the quantum yield of photosystem II was observed after 24 h exposure and thereafter a recovery trend was observed. Motility, gravitaxis and cell shape were strongly impaired immediately upon exposure to the detergent, but with increasing exposure time these parameters showed acclimatization to the stress and thus the NOEC values obtained after 72 h were higher than those immediately after exposure. Copyright © 2011 Elsevier Ltd. All rights reserved.

  4. Role of detergents in conformational exchange of a G protein-coupled receptor.

    PubMed

    Chung, Ka Young; Kim, Tae Hun; Manglik, Aashish; Alvares, Rohan; Kobilka, Brian K; Prosser, R Scott

    2012-10-19

    The G protein-coupled β(2)-adrenoreceptor (β(2)AR) signals through the heterotrimeric G proteins G(s) and G(i) and β-arrestin. As such, the energy landscape of β(2)AR-excited state conformers is expected to be complex. Upon tagging Cys-265 of β(2)AR with a trifluoromethyl probe, (19)F NMR was used to assess conformations and possible equilibria between states. Here, we report key differences in β(2)AR conformational dynamics associated with the detergents used to stabilize the receptor. In dodecyl maltoside (DDM) micelles, the spectra are well represented by a single Lorentzian line that shifts progressively downfield with activation by appropriate ligand. The results are consistent with interconversion between two or more states on a time scale faster than the greatest difference in ligand-dependent chemical shift (i.e. >100 Hz). Given that high detergent off-rates of DDM monomers may facilitate conformational exchange between functional states of β(2)AR, we utilized the recently developed maltose-neopentyl glycol (MNG-3) diacyl detergent. In MNG-3 micelles, spectra indicated at least three distinct states, the relative populations of which depended on ligand, whereas no ligand-dependent shifts were observed, consistent with the slow exchange limit. Thus, detergent has a profound effect on the equilibrium kinetics between functional states. MNG-3, which has a critical micelle concentration in the nanomolar regime, exhibits an off-rate that is 4 orders of magnitude lower than that of DDM. High detergent off-rates are more likely to facilitate conformational exchange between distinct functional states associated with the G protein-coupled receptor.

  5. Characterization of detergent-solubilized sarcoplasmic reticulum Ca2+-ATPase by high-performance liquid chromatography.

    PubMed

    Andersen, J P; Vilsen, B; Nielsen, H; Møller, J V

    1986-10-21

    Sarcoplasmic reticulum Ca2+-ATPase solubilized by the nonionic detergent octaethylene glycol monododecyl ether was studied by molecular sieve high-performance liquid chromatography (HPLC) and analytical ultracentrifugation. Significant irreversible aggregation of soluble Ca2+-ATPase occurred within a few hours in the presence of less than or equal to 50 microM Ca2+. The aggregates were inactive and were primarily held together by hydrophobic forces. In the absence of reducing agent, secondary formation of disulfide bonds occurred. The stability of the inactive dimer upon dilution permitted unambiguous assignment of its elution position and sedimentation coefficient. At high Ca2+ concentration (500 microM), monomeric Ca2+-ATPase was stable for several hours. Reversible self-association induced by variation in protein, detergent, and lipid concentrations was studied by large-zone HPLC. The association constant for dimerization of active Ca2+-ATPase was found to be 10(5)-10(6) M-1 depending on the detergent concentration. More detergent was bound to monomeric than to dimeric Ca2+-ATPase, even above the critical micellar concentration of the detergent. Binding of Ca2+ and vanadate as well as ATP-dependent phosphorylation was studied in monomeric and in reversibly associated dimeric preparations. In both forms, two high-affinity Ca2+ binding sites per phosphorylation site existed. The delipidated monomer purified by HPLC was able to form ADP-insensitive phosphoenzyme and to bind ATP and vanadate simultaneously. These results suggest that formation of Ca2+-ATPase oligomers in the membrane is governed by nonspecific forces (low affinity) and that each polypeptide chain constitutes a functional unit.

  6. 40 CFR 80.160 - Exemptions.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ..., automobile, engine, or component manufacturers for research, development, or test purposes, or any gasoline... such facility is associated with detergent, fuel, automotive, or engine research, development or... FUELS AND FUEL ADDITIVES Detergent Gasoline § 80.160 Exemptions. (a) Research, development, and testing...

  7. 40 CFR 80.160 - Exemptions.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ..., automobile, engine, or component manufacturers for research, development, or test purposes, or any gasoline... such facility is associated with detergent, fuel, automotive, or engine research, development or... FUELS AND FUEL ADDITIVES Detergent Gasoline § 80.160 Exemptions. (a) Research, development, and testing...

  8. 40 CFR 80.160 - Exemptions.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ..., automobile, engine, or component manufacturers for research, development, or test purposes, or any gasoline... such facility is associated with detergent, fuel, automotive, or engine research, development or... FUELS AND FUEL ADDITIVES Detergent Gasoline § 80.160 Exemptions. (a) Research, development, and testing...

  9. 40 CFR 80.173 - Exemptions.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ..., automobile, engine, or component manufacturers for research, development, or test purposes, or any gasoline... such facility is associated with detergent, fuel, automotive, or engine research, development or... FUELS AND FUEL ADDITIVES Detergent Gasoline § 80.173 Exemptions. (a) Research, development, and testing...

  10. 40 CFR 80.173 - Exemptions.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ..., automobile, engine, or component manufacturers for research, development, or test purposes, or any gasoline... such facility is associated with detergent, fuel, automotive, or engine research, development or... FUELS AND FUEL ADDITIVES Detergent Gasoline § 80.173 Exemptions. (a) Research, development, and testing...

  11. 40 CFR 80.173 - Exemptions.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ..., automobile, engine, or component manufacturers for research, development, or test purposes, or any gasoline... such facility is associated with detergent, fuel, automotive, or engine research, development or... FUELS AND FUEL ADDITIVES Detergent Gasoline § 80.173 Exemptions. (a) Research, development, and testing...

  12. 40 CFR 80.160 - Exemptions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ..., automobile, engine, or component manufacturers for research, development, or test purposes, or any gasoline... such facility is associated with detergent, fuel, automotive, or engine research, development or... FUELS AND FUEL ADDITIVES Detergent Gasoline § 80.160 Exemptions. (a) Research, development, and testing...

  13. 40 CFR 80.160 - Exemptions.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ..., automobile, engine, or component manufacturers for research, development, or test purposes, or any gasoline... such facility is associated with detergent, fuel, automotive, or engine research, development or... FUELS AND FUEL ADDITIVES Detergent Gasoline § 80.160 Exemptions. (a) Research, development, and testing...

  14. 40 CFR 80.173 - Exemptions.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ..., automobile, engine, or component manufacturers for research, development, or test purposes, or any gasoline... such facility is associated with detergent, fuel, automotive, or engine research, development or... FUELS AND FUEL ADDITIVES Detergent Gasoline § 80.173 Exemptions. (a) Research, development, and testing...

  15. 40 CFR 80.173 - Exemptions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ..., automobile, engine, or component manufacturers for research, development, or test purposes, or any gasoline... such facility is associated with detergent, fuel, automotive, or engine research, development or... FUELS AND FUEL ADDITIVES Detergent Gasoline § 80.173 Exemptions. (a) Research, development, and testing...

  16. 40 CFR 417.154 - [Reserved

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 28 2010-07-01 2010-07-01 true [Reserved] 417.154 Section 417.154 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS SOAP AND DETERGENT MANUFACTURING POINT SOURCE CATEGORY Manufacture of Spray Dried Detergents Subcategory...

  17. 40 CFR 417.154 - [Reserved

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 29 2014-07-01 2012-07-01 true [Reserved] 417.154 Section 417.154 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS SOAP AND DETERGENT MANUFACTURING POINT SOURCE CATEGORY Manufacture of Spray Dried Detergents Subcategory...

  18. 40 CFR 417.154 - [Reserved

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 29 2011-07-01 2009-07-01 true [Reserved] 417.154 Section 417.154 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS SOAP AND DETERGENT MANUFACTURING POINT SOURCE CATEGORY Manufacture of Spray Dried Detergents Subcategory...

  19. 40 CFR 417.154 - [Reserved

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 30 2012-07-01 2012-07-01 false [Reserved] 417.154 Section 417.154 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS SOAP AND DETERGENT MANUFACTURING POINT SOURCE CATEGORY Manufacture of Spray Dried Detergents Subcategory...

  20. 40 CFR 80.141 - Interim detergent gasoline program.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... considered acceptable for demonstration of IVD control performance. Examples of acceptable test procedures... carburetor deposits. Examples of acceptable test procedures for demonstration of carburetor deposit control... ultimate consumer; (ii) All additized post-refinery component (PRC); and (iii) All detergent additives sold...

  1. 40 CFR 80.141 - Interim detergent gasoline program.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... considered acceptable for demonstration of IVD control performance. Examples of acceptable test procedures... carburetor deposits. Examples of acceptable test procedures for demonstration of carburetor deposit control... ultimate consumer; (ii) All additized post-refinery component (PRC); and (iii) All detergent additives sold...

  2. 40 CFR 80.141 - Interim detergent gasoline program.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... considered acceptable for demonstration of IVD control performance. Examples of acceptable test procedures... carburetor deposits. Examples of acceptable test procedures for demonstration of carburetor deposit control... ultimate consumer; (ii) All additized post-refinery component (PRC); and (iii) All detergent additives sold...

  3. 40 CFR 80.141 - Interim detergent gasoline program.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... considered acceptable for demonstration of IVD control performance. Examples of acceptable test procedures... carburetor deposits. Examples of acceptable test procedures for demonstration of carburetor deposit control... ultimate consumer; (ii) All additized post-refinery component (PRC); and (iii) All detergent additives sold...

  4. 27 CFR 21.37 - Formula No. 3-C.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... intermediates and industrial collodions. 035.Soldering flux. 036.Adhesives and binders. 043.Solvents, special... solutions. 440.Industrial detergents and soaps. 450.Cleaning solutions (including household detergents). 470...: 530.Ethylamines. 540.Dyes and intermediates. 575.Drugs and medicinal chemicals. 576.Organo-silicone...

  5. 27 CFR 21.37 - Formula No. 3-C.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... intermediates and industrial collodions. 035.Soldering flux. 036.Adhesives and binders. 043.Solvents, special... solutions. 440.Industrial detergents and soaps. 450.Cleaning solutions (including household detergents). 470...: 530.Ethylamines. 540.Dyes and intermediates. 575.Drugs and medicinal chemicals. 576.Organo-silicone...

  6. 27 CFR 21.37 - Formula No. 3-C.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... intermediates and industrial collodions. 035.Soldering flux. 036.Adhesives and binders. 043.Solvents, special... solutions. 440.Industrial detergents and soaps. 450.Cleaning solutions (including household detergents). 470...: 530.Ethylamines. 540.Dyes and intermediates. 575.Drugs and medicinal chemicals. 576.Organo-silicone...

  7. 27 CFR 21.35 - Formula No. 3-A.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... intermediates and industrial collodions. 035.Soldering flux. 036.Adhesives and binders. 041.Proprietary solvents... solutions. 440.Industrial detergents and soaps. 450.Cleaning solutions (including household detergents). 470...: 530.Ethylamines. 540.Dyes and intermediates. 575.Drugs and medicinal chemicals. 576.Organo-silicone...

  8. 27 CFR 21.35 - Formula No. 3-A.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... intermediates and industrial collodions. 035.Soldering flux. 036.Adhesives and binders. 041.Proprietary solvents... solutions. 440.Industrial detergents and soaps. 450.Cleaning solutions (including household detergents). 470...: 530.Ethylamines. 540.Dyes and intermediates. 575.Drugs and medicinal chemicals. 576.Organo-silicone...

  9. 27 CFR 21.37 - Formula No. 3-C.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... intermediates and industrial collodions. 035.Soldering flux. 036.Adhesives and binders. 043.Solvents, special... solutions. 440.Industrial detergents and soaps. 450.Cleaning solutions (including household detergents). 470...: 530.Ethylamines. 540.Dyes and intermediates. 575.Drugs and medicinal chemicals. 576.Organo-silicone...

  10. 27 CFR 21.37 - Formula No. 3-C.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... intermediates and industrial collodions. 035.Soldering flux. 036.Adhesives and binders. 043.Solvents, special... solutions. 440.Industrial detergents and soaps. 450.Cleaning solutions (including household detergents). 470...: 530.Ethylamines. 540.Dyes and intermediates. 575.Drugs and medicinal chemicals. 576.Organo-silicone...

  11. 27 CFR 21.35 - Formula No. 3-A.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... intermediates and industrial collodions. 035.Soldering flux. 036.Adhesives and binders. 041.Proprietary solvents... solutions. 440.Industrial detergents and soaps. 450.Cleaning solutions (including household detergents). 470...: 530.Ethylamines. 540.Dyes and intermediates. 575.Drugs and medicinal chemicals. 576.Organo-silicone...

  12. 27 CFR 21.35 - Formula No. 3-A.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... intermediates and industrial collodions. 035.Soldering flux. 036.Adhesives and binders. 041.Proprietary solvents... solutions. 440.Industrial detergents and soaps. 450.Cleaning solutions (including household detergents). 470...: 530.Ethylamines. 540.Dyes and intermediates. 575.Drugs and medicinal chemicals. 576.Organo-silicone...

  13. 27 CFR 21.35 - Formula No. 3-A.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... intermediates and industrial collodions. 035.Soldering flux. 036.Adhesives and binders. 041.Proprietary solvents... solutions. 440.Industrial detergents and soaps. 450.Cleaning solutions (including household detergents). 470...: 530.Ethylamines. 540.Dyes and intermediates. 575.Drugs and medicinal chemicals. 576.Organo-silicone...

  14. 40 CFR 417.164 - [Reserved

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 28 2010-07-01 2010-07-01 true [Reserved] 417.164 Section 417.164 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS SOAP AND DETERGENT MANUFACTURING POINT SOURCE CATEGORY Manufacture of Liquid Detergents Subcategory § 417...

  15. Anaerobic Biodegradation of Detergent Surfactants

    PubMed Central

    Merrettig-Bruns, Ute; Jelen, Erich

    2009-01-01

    Detergent surfactants can be found in wastewater in relevant concentrations. Most of them are known as ready degradable under aerobic conditions, as required by European legislation. Far fewer surfactants have been tested so far for biodegradability under anaerobic conditions. The natural environment is predominantly aerobic, but there are some environmental compartments such as river sediments, sub-surface soil layer and anaerobic sludge digesters of wastewater treatment plants which have strictly anaerobic conditions. This review gives an overview on anaerobic biodegradation processes, the methods for testing anaerobic biodegradability, and the anaerobic biodegradability of different detergent surfactant types (anionic, nonionic, cationic, amphoteric surfactants).

  16. Mechanisms of anionic detergent-induced hemolysis.

    PubMed

    Chernitsky, E; Senkovich, O

    1998-09-01

    The effect of osmotic protectors (sucrose and polyethylene glycols) and of a decrease in the detergent concentration at different points of hemolysis of human erythrocytes by sodium dodecyl sulphate on the shape of kinetic curves of hemolysis were studied. It is shown that slow detergent-induced hemolysis follows the colloid-osmotic mechanisms. Evidence is provided that rapid hemolysis by sodium dodecyl sulphate is caused by opening of large pores sufficient for the release of hemoglobin molecules rather than by the colloid-osmotic mechanism, and that the kinetics of hemolysis is mainly determined by time dependence of the opening probability of these pores.

  17. Efficient production and purification of functional bacteriorhodopsin with a wheat-germ cell-free system and a combination of Fos-choline and CHAPS detergents.

    PubMed

    Genji, Takahisa; Nozawa, Akira; Tozawa, Yuzuru

    2010-10-01

    Cell-free translation is one potential approach to the production of functional transmembrane proteins. We have now examined various detergents as supplements to a wheat-germ cell-free system in order to optimize the production and subsequent purification of a functional model transmembrane protein, bacteriorhodopsin. We found that Fos-choline and CHAPS detergents counteracted each other's inhibitory effects on cell-free translation activity and thereby allowed the efficient production and subsequent purification of functional bacteriorhodopsin in high yield. Copyright © 2010 Elsevier Inc. All rights reserved.

  18. Enhanced gene delivery to the lung using biodegradable polyunsaturated cationic phosphatidylcholine-detergent conjugates.

    PubMed

    Pierrat, Philippe; Kereselidze, Dimitri; Lux, Marie; Lebeau, Luc; Pons, Françoise

    2016-09-10

    Lung diseases are among the more representative causes of mortality and morbidity worldwide and gene therapy is considered as a promising therapeutic approach for their treatment. However the design of efficient nucleic acid carriers for airway administration still is a challenge and there is a pressing need for new developments in this field. Herein, new synthetic DNA carriers based on the conjugation of a phospholipid and C12E4, a nonionic detergent, are developed. DNA complexes with phosphatidylcholine-detergent conjugates are administered in mouse airways, and transgene expression and inflammatory activity as an index of toxicity are investigated as a function of time, DNA dose, and presence of helper and stealth lipids. Introduction of a biodegradable linker between the phosphatidylcholine and detergent moieties significantly attenuates the severity of inflammatory response that characterizes cationic lipid-mediated gene transfer. Concurrent introduction of polyunsaturated fatty acid chains in the carrier scaffold improves transgene expression and further reduces airway inflammation. Finally, the biodegradable phosphatidylcholine-detergent conjugates favorably compare to GL67A, the gold standard for DNA delivery to the airway that is currently under clinical evaluation. Our findings indicate that the lipid formulations described herein may have great potential as nucleic acid carriers for gene therapy. Copyright © 2016 Elsevier B.V. All rights reserved.

  19. Differential detergent resistance of the apical and basolateral NPPases: relationship with polarized targeting.

    PubMed

    Delaunay, Jean-Louis; Breton, Michelyne; Goding, James W; Trugnan, Germain; Maurice, Michèle

    2007-03-15

    Targeting of glycosylphosphatidylinositol-anchored proteins to the apical surface of epithelial cells involves clustering in Triton X-100-resistant membrane microdomains or rafts. The role of these microdomains in sorting transmembrane proteins is more questionable because, unlike glycosylphosphatidylinositol-anchored proteins, apical transmembrane proteins are rather soluble in Triton X-100. They are, however, resistant to milder detergents such as Lubrol WX or Tween 20. It has been proposed that specific membrane microdomains, defined by resistance to these detergents, would carry transmembrane proteins to the apical surface. We have used MDCK cells stably transfected with the apical and basolateral pyrophosphatases/phosphodiesterases, NPP3 and NPP1, to examine the relationship between detergent resistance and apical targeting. The apically expressed wild-type NPP3 was insoluble in Lubrol WX whereas wild-type NPP1, which is expressed basolaterally, was essentially soluble. By using tail mutants and chimeric constructs that combine the cytoplasmic, transmembrane and extracellular domains of NPP1 and NPP3, we show that there is not a strict correlation between detergent resistance and apical targeting. Lubrol resistance is an intrinsic property of NPP3, which is acquired early during the biosynthetic process irrespective of its final destination, and depends on positively charged residues in its cytoplasmic tail.

  20. Jatropha oil derived sophorolipids: production and characterization as laundry detergent additive.

    PubMed

    Joshi-Navare, Kasturi; Khanvilkar, Poonam; Prabhune, Asmita

    2013-01-01

    Sophorolipids (SLs) are glycolipidic biosurfactants suitable for various biological and physicochemical applications. The nonedible Jatropha oil has been checked as the alternative raw material for SL synthesis using C. bombicola (ATCC22214). This is useful towards lowering the SL production cost. Through optimization of fermentation parameters and use of resting cell method, the yield 15.25 g/L could be achieved for Jatropha oil derived SL (SLJO) with 1% v/v oil feeding. The synthesized SL displayed good surfactant property. It reduced the surface tension of distilled water from 70.7 mN/m to 33.5 mN/m with the Critical Micelle Concentration (CMC) value of 9.5 mg/L. Keeping the prospective use of the SL in mind, the physicochemical properties were checked along with emulsion stability under temperature, pH stress, and in hard water. Also antibacterial action and stain removal capability in comparison with commercial detergent was demonstrated. SLJO enhanced the detergent performance. Based on the results, it can be said that SLs have utility as fabric cleaner with advantageous properties such as skin friendly nature, antibacterial action, and biodegradability. Therefore SLs are potential green molecules to replace synthetic surfactants in detergents so as to reduce harm caused to environment through detergent usage.

  1. Inclusion of detergent in a cleaning regime and effect on microbial load in livestock housing

    PubMed Central

    Hancox, L. R.; Le Bon, M.; Dodd, C. E. R.; Mellits, K. H.

    2013-01-01

    Determining effective cleaning and disinfection regimes of livestock housing is vital to improving the health of resident animals and reducing zoonotic disease. A cleaning regime consisting of scraping, soaking with or without detergent (treatment and control), pressure washing, disinfection and natural drying was applied to multiple pig pens. After each cleaning stage, samples were taken from different materials and enumerated for total aerobic count (TAC) and Enterobacteriaceae (ENT). Soaking with detergent (Blast-Off, Biolink) caused significantly greater reductions of TAC and ENT on metal, and TAC on concrete, compared with control. Disinfection effect (Virkon S, DuPont) was not significantly associated with prior detergent treatment. Disinfection significantly reduced TAC and ENT on concrete and stock board but not on metal. Twenty-four hours after disinfection TAC and ENT on metal and stock board were significantly reduced, but no significant reductions occurred in the subsequent 96 hours. Counts on concrete did not significantly reduce during the entire drying period (120 hours). Detergent and disinfectant have varying bactericidal effects according to the surface and bacterial target; however, both can significantly reduce microbial numbers so should be used during cleaning, with a minimum drying period of 24 hours, to lower bacterial counts effectively. PMID:23839725

  2. Influence of the surrounding environment in re-naturalized β-barrel membrane proteins.

    PubMed

    Lopes-Rodrigues, Maximilien; Triguero, Jordi; Torras, Juan; Perpète, Eric A; Michaux, Catherine; Zanuy, David; Alemán, Carlos

    2018-03-01

    Outer-membrane porins are currently being used to prepare bioinspired nanomembranes for selective ion transport by immobilizing them into polymeric matrices. However, the fabrication of these protein-integrated devices has been found to be strongly influenced by the instability of the β-barrel porin structure, which depends on surrounding environment. In this work, molecular dynamics simulations have been used to investigate the structural stability of a representative porin, OmpF, in three different environments: (i) aqueous solution at pH=7; (ii) a solution of neutral detergent in a concentration similar to the critical micelle concentration; and (iii) the protein embedded into a neutral detergent bilayer. The results indicate that the surrounding environment not only alters the stability of the β-barrel but affects the internal loop responsible of the ions transport, as well as the tendency of the porin proteins to aggregate into trimers. The detergent bilayer preserves the structure of OmpF protein as is found bacteria membranes, while pure aqueous solution induces a strong destabilization of the protein. An intermediate situation occurs for detergent solution. Our results have been rationalized in terms of protein⋯water and protein⋯detergent interactions, which makes them extremely useful for the future design of new generation of bioinspired protein-integrated devices. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. Detergent-Mediated Formation of β-Hematin: Heme Crystallization Promoted by Detergents Implicates Nanostructure Formation for Use as a Biological Mimic

    PubMed Central

    2016-01-01

    Hemozoin is a unique biomineral that results from the sequestration of toxic free heme liberated as a consequence of hemoglobin degradation in the malaria parasite. Synthetic neutral lipid droplets (SNLDs) and phospholipids were previously shown to support the rapid formation of β-hematin, abiological hemozoin, under physiologically relevant pH and temperature, though the mechanism by which heme crystallization occurs remains unclear. Detergents are particularly interesting as a template because they are amphiphilic molecules that spontaneously organize into nanostructures and have been previously shown to mediate β-hematin formation. Here, 11 detergents were investigated to elucidate the physicochemical properties that best recapitulate crystal formation in the parasite. A strong correlation between the detergent’s molecular structure and the corresponding kinetics of β-hematin formation was observed, where higher molecular weight polar chains promoted faster reactions. The larger hydrophilic chains correlated to the detergent’s ability to rapidly sequester heme into the lipophilic core, allowing for crystal nucleation to occur. The data presented here suggest that detergent nanostructures promote β-hematin formation in a similar manner to SNLDs and phospholipids. Through understanding mediator properties that promote optimal crystal formation, we are able to establish an in vitro assay to probe this drug target pathway. PMID:27175104

  4. Polyol and Amino Acid-Based Biosurfactants, Builders, and Hydrogels

    USDA-ARS?s Scientific Manuscript database

    This chapter reviews different detergent materials which have been synthesized from natural agricultural commodities. Background information, which gives reasons why the use of biobased materials may be advantageous, is presented. Detergent builders from L-aspartic acid, citric acid and D-sorbitol...

  5. Modulation of protein function in membrane mimetics: Characterization of P. denitrificans cNOR in nanodiscs or liposomes.

    PubMed

    Ter Beek, Josy; Kahle, Maximilian; Ädelroth, Pia

    2017-10-01

    For detailed functional characterization, membrane proteins are usually studied in detergent. However, it is becoming clear that detergent micelles are often poor mimics of the lipid environment in which these proteins function. In this work we compared the catalytic properties of the membrane-embedded cytochrome c-dependent nitric oxide reductase (cNOR) from Paracoccus (P.) denitrificans in detergent, lipid/protein nanodiscs, and proteoliposomes. We used two different lipid mixtures, an extract of soybean lipids and a defined mix of synthetic lipids mimicking the original P. denitrificans membrane. We show that the catalytic activity of detergent-solubilized cNOR increased threefold upon reconstitution from detergent into proteoliposomes with the P. denitrificans lipid mixture, and above two-fold when soybean lipids were used. In contrast, there was only a small activity increase in nanodiscs. We further show that binding of the gaseous ligands CO and O 2 are affected differently by reconstitution. In proteoliposomes the turnover rates are affected much more than in nanodiscs, but CO-binding is more significantly accelerated in liposomes with soybean lipids, while O 2 -binding is faster with the P. denitrificans lipid mix. We also investigated proton-coupled electron transfer during the reaction between fully reduced cNOR and O 2 , and found that the pK a of the internal proton donor was increased in proteoliposomes but not in nanodiscs. Taking our results together, the liposome-reconstituted enzyme shows significant differences to detergent-solubilized protein. Nanodiscs show much more subtle effects, presumably because of their much lower lipid to protein ratio. Which of these two membrane-mimetic systems best mimics the native membrane is discussed. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Lipid, Detergent, and Coomassie Blue G-250 Affect the Migration of Small Membrane Proteins in Blue Native Gels

    PubMed Central

    Crichton, Paul G.; Harding, Marilyn; Ruprecht, Jonathan J.; Lee, Yang; Kunji, Edmund R. S.

    2013-01-01

    Blue native gel electrophoresis is a popular method for the determination of the oligomeric state of membrane proteins. Studies using this technique have reported that mitochondrial carriers are dimeric (composed of two ∼32-kDa monomers) and, in some cases, can form physiologically relevant associations with other proteins. Here, we have scrutinized the behavior of the yeast mitochondrial ADP/ATP carrier AAC3 in blue native gels. We find that the apparent mass of AAC3 varies in a detergent- and lipid-dependent manner (from ∼60 to ∼130 kDa) that is not related to changes in the oligomeric state of the protein, but reflects differences in the associated detergent-lipid micelle and Coomassie Blue G-250 used in this technique. Higher oligomeric state species are only observed under less favorable solubilization conditions, consistent with aggregation of the protein. Calibration with an artificial covalent AAC3 dimer indicates that the mass observed for solubilized AAC3 and other mitochondrial carriers corresponds to a monomer. Size exclusion chromatography of purified AAC3 in dodecyl maltoside under blue native gel-like conditions shows that the mass of the monomer is ∼120 kDa, but appears smaller on gels (∼60 kDa) due to the unusually high amount of bound negatively charged dye, which increases the electrophoretic mobility of the protein-detergent-dye micelle complex. Our results show that bound lipid, detergent, and Coomassie stain alter the behavior of mitochondrial carriers on gels, which is likely to be true for other small membrane proteins where the associated lipid-detergent micelle is large when compared with the mass of the protein. PMID:23744064

  7. Fatty acid profiles from the plasma membrane and detergent resistant membranes of two plant species.

    PubMed

    Carmona-Salazar, Laura; El Hafidi, Mohammed; Gutiérrez-Nájera, Nora; Noyola-Martínez, Liliana; González-Solís, Ariadna; Gavilanes-Ruíz, Marina

    2015-01-01

    It is essential to establish the composition of the plant plasma membrane in order to understand its organization and behavior under continually changing environments. Knowledge of the lipid phase, in particular the fatty acid (FA) complex repertoire, is important since FAs determine many of the physical-chemical membrane properties. FAs are constituents of the membrane glycerolipid and sphingolipid backbones and can also be linked to some sterols. In addition, FAs are components of complex lipids that can constitute membrane micro-domains, and the use of detergent-resistant membranes is a common approach to study their composition. The diversity and cellular allocation of the membrane lipids containing FAs are very diverse and the approaches to analyze them provide only general information. In this work, a detailed FA analysis was performed using highly purified plasma membranes from bean leaves and germinating maize embryos and their respective detergent-resistant membrane preparations. The analyses showed the presence of a significant amount of very long chain FAs (containing 28C, 30C and 32C), in both plasma membrane preparations from bean and maize, that have not been previously reported. Herein is demonstrated that a significant enrichment of very long chain saturated FAs and saturated FAs can occur in detergent-resistant membrane preparations, as compared to the plasma membranes from both plant species. Considering that a thorough analysis of FAs is rarely performed in purified plasma membranes and detergent-resistant membranes, this work provides qualitative and quantitative evidence on the contributions of the length and saturation of FAs to the organization of the plant plasma membrane and detergent-resistant membranes. Copyright © 2014 Elsevier Ltd. All rights reserved.

  8. Characterization of Hydrophobic Peptides in the Presence of Detergent by Photoionization Mass Spectrometry

    PubMed Central

    Bagag, Aïcha; Jault, Jean-Michel; Sidahmed-Adrar, Nazha; Réfrégiers, Matthieu; Giuliani, Alexandre; Le Naour, François

    2013-01-01

    The characterization of membrane proteins is still challenging. The major issue is the high hydrophobicity of membrane proteins that necessitates the use of detergents for their extraction and solubilization. The very poor compatibility of mass spectrometry with detergents remains a tremendous obstacle in studies of membrane proteins. Here, we investigated the potential of atmospheric pressure photoionization (APPI) for mass spectrometry study of membrane proteins. This work was focused on the tetraspanin CD9 and the multidrug transporter BmrA. A set of peptides from CD9, exhibiting a broad range of hydropathicity, was investigated using APPI as compared to electrospray ionization (ESI). Mass spectrometry experiments revealed that the most hydrophobic peptides were hardly ionized by ESI whereas all peptides, including the highly hydrophobic one that corresponds to the full sequence of the first transmembrane domain of CD9, were easily ionized by APPI. The native protein BmrA purified in the presence of the non-ionic detergent beta-D-dodecyl maltoside (DDM) was digested in-solution using trypsin. The resulting peptides were investigated by flow injection analysis of the mixture followed by mass spectrometry. Upon ESI, only detergent ions were detected and the ionic signals from the peptides were totally suppressed. In contrast, APPI allowed many peptides distributed along the sequence of the protein to be detected. Furthermore, the parent ion corresponding to the first transmembrane domain of the protein BmrA was detected under APPI conditions. Careful examination of the APPI mass spectrum revealed a-, b-, c- and y- fragment ions generated by in-source fragmentation. Those fragment ions allowed unambiguous structural characterization of the transmembrane domain. In conclusion, APPI–MS appears as a versatile method allowing the ionization and fragmentation of hydrophobic peptides in the presence of detergent. PMID:24236085

  9. Laundry Detergency of Solid Non-Particulate Soil Using Microemulsion-Based Formulation.

    PubMed

    Chanwattanakit, Jarussri; Chavadej, Sumaeth

    2018-02-01

    Laundry detergency of solid non-particulate soil on polyester and cotton was investigated using a microemulsion-based formulation, consisting of an anionic extended surfactant (C 12,13 -4PO-SO 4 Na) and sodium mono-and di-methyl naphthalene sulfonate (SMDNS) as the hydrophilic linker, to provide a Winsor Type III microemulsion with an ultralow interfacial tension (IFT). In this work, methyl palmitate (palmitic acid methyl ester) having a melting point around 30°C, was used as a model solid non-particulate (waxy) soil. A total surfactant concentration of 0.35 wt% of the selected formulation (4:0.65 weight ratio of C 12,13 -4PO-SO 4 Na:SMDNS) with 5.3 wt% NaCl was able to form a middle phase microemulsion at a high temperature (40°C),which provided the highest oil removal level with the lowest oil redeposition and the lowest IFT, and was much higher than that with a commercial detergent or de-ionized water. Most of the detached oil, whether in liquid or solid state, was in an unsolubilized form. Hence, the dispersion stability of the detached oil droplets or solidified oil particles that resulted from the surfactant adsorption played an important role in the oil redeposition. For an oily detergency, the lower the system IFT, the higher the oil removal whereas for a waxy (non-particulate) soil detergency, the lower the contact angle, the higher the solidified oil removal. For a liquefied oil, the detergency mechanism was roll up and emulsification with dispersion stability, while that for the waxy soil (solid oil) was the detachment by wettability with dispersion stability.

  10. Thermostable, alkaline and detergent-tolerant lipase from a newly isolated thermophilic Bacillus stearothermophilus.

    PubMed

    Ben Bacha, Abir; Moubayed, Nadine M S; Abid, Islam

    2015-04-01

    Lipases are the enzymes of choice for laundry detergent industries, owing to their triglyceride removing ability from the soiled fabric, which eventually reduces the usage of phosphate-based chemical cleansers in the detergent formulation. In this study, a novel thermo-alkaline lipase-producing strain identified as Bacillus stearothermophilus was isolated from the soil samples of olive oil mill. Enhanced lipase production was observed at 55 degrees C, pH 11 and after 48 h of incubation. Among the substrates tested, xylose (a carbon source), peptone (a nitrogen source) and olive oil at a concentration of 1% were suitable substrates for enhancing lipase production. MgSO4 and Tween-80 were suitable substrates for maximizing lipase production. The enzyme was purified to homogeneity by a single CM-Sephadex column chromatography and revealed molecular mass of 67 kDa. The enzyme (BL1) was active over a wide range of pH from 9.0 to 13.0, with an optimum at pH 11.0, exhibited maximal activity at 55 degreesC and retained more than 70% of its activity after incubation at 70 degrees C or pH 13 for 0.5 h or 24 h, respectively. The enzyme hydrolyzed both short and long-chain triacylglycerols at comparable rates. BL1 was studied in a preliminary evaluation for use in detergent formulation solutions. This novel lipase showed extreme stability towards non-ionic and anionic surfactants after pre-incubation for 1 h at 40 degrees C, and good stability towards oxidizing agents. Additionally, the enzyme showed excellent stability and compatibility with various commercial detergents, suggesting its potential as an additive in detergent formulations.

  11. Size And Shape of Detergent Micelles Determined By Small-Angle X-Ray Scattering

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lipfert, Jan; Columbus, Linda; Chu, Vincent B.

    2009-04-29

    We present a systematic analysis of the aggregation number and shape of micelles formed by nine detergents commonly used in the study of membrane proteins. Small-angle X-ray scattering measurements are reported for glucosides with 8 and 9 alkyl carbons (OG/NG), maltosides and phosphocholines with 10 and 12 alkyl carbons (DM/DDM and FC-10/FC-12), 1,2-dihexanoyl-sn-glycero-phosphocholine (DHPC), 1-palmitoyl-2-hydroxy-sn-glycero-3-[phospho-rac-(1-glycerol)] (LPPG), and 3-[(3-cholamidopropyl)dimethylammonio]-1-propane sulfonate (CHAPS). The SAXS intensities are well described by two-component ellipsoid models, with a dense outer shell corresponding to the detergent head groups and a less electron dense hydrophobic core. These models provide an intermediate resolution view of micelle size and shape.more » In addition, we show that Guinier analysis of the forward scattering intensity can be used to obtain an independent and model-free measurement of the micelle aggregation number and radius of gyration. This approach has the advantage of being easily generalizable to protein-detergent complexes, where simple geometric models are inapplicable. Furthermore, we have discovered that the position of the second maximum in the scattering intensity provides a direct measurement of the characteristic head group-head group spacing across the micelle core. Our results for the micellar aggregation numbers and dimensions agree favorably with literature values as far as they are available. We de novo determine the shape of FC-10, FC-12, DM, LPPG, and CHAPS micelles and the aggregation numbers of FC-10 and OG to be ca. 50 and 250, respectively. Combined, these data provide a comprehensive view of the determinants of micelle formation and serve as a starting point to correlate detergent properties with detergent-protein interactions.« less

  12. 40 CFR 417.196 - Pretreatment standards for new sources.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 28 2010-07-01 2010-07-01 true Pretreatment standards for new sources. 417.196 Section 417.196 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS SOAP AND DETERGENT MANUFACTURING POINT SOURCE CATEGORY Manufacture of Detergent Bars...

  13. Novel Procedure for Extraction of a Latent Grape Polyphenoloxidase Using Temperature-Induced Phase Separation in Triton X-114 1

    PubMed Central

    Sánchez-Ferrer, Alvaro; Bru, Roque; Garcia-Carmona, Francisco

    1989-01-01

    Polyphenoloxidase from grape berries is extracted only by nonionic detergents with a hydrophilic-lipophilic balance between 12.4 and 13.5. The enzyme was partially purified in latent form, free of phenolics and chlorophylls, by using temperature phase partitioning in a solution of Triton X-114. This method permits the purification of the enzyme with the same fold purification as the commonly used method, but with a yield three times higher and a 90% reduction in time needed. The latent enzyme can be activated by different treatments, including trypsin and cationic and anionic detergents. Cetyltrimethylamonium bromide was found to be the most effective detergent activator, followed by sodium dodecyl sulfate. Polyphenoloxidase in grape berries, in spite of being an integral membrane protein, had an anomalous interaction with Triton X-114, remaining in the detergent-poor phase after phase separation. This could be explained by its having a short hydrophobic tail that anchors it to the membrane. Images Figure 1 Figure 3 PMID:16667205

  14. Pigmented and hyperkeratotic napkin dermatitis: a liquid detergent irritant dermatitis.

    PubMed

    Patrizi, A; Neri, I; Marzaduri, S; Fiorillo, L

    1996-01-01

    Napkin or diaper dermatitis (DD) is an inflammatory cutaneous eruption limited to the diaper area and common in the first 2 years of life. A number of clinical variants of DD have been identified. We report a new variant of DD characterized by papyraceous skin, brownish discoloration and predilection for the depth of folds. 15 infants and toddlers affected by this peculiar type of DD were evaluated regarding duration, localization, morphology and evolution of their dermatosis. This variant of DD was mainly confined to the depth of inguinal and gluteal folds and invariably associated with severe xerosis with papyraceous and glazed skin. The patients were healthy and asymptomatic and all laboratory investigations performed were normal. All patients were frequently changed and thoroughly washed with synthetic detergents with acid pH. DD improved rapidly with reduced frequency of washing and discontinuation of liquid detergents. We conclude that this condition is a type of irritant contact dermatitis from excessive use of lipid acid detergents.

  15. Spectroscopic studies on the active site of hydroperoxide lyase; the influence of detergents on its conformation.

    PubMed

    Noordermeer, M A; Veldink, G A; Vliegenthart, J F

    2001-02-02

    Expression of high quantities of alfalfa hydroperoxide lyase in Escherichia coli made it possible to study its active site and structure in more detail. Circular dichroism (CD) spectra showed that hydroperoxide lyase consists for about 75% of alpha-helices. Electron paramagnetic resonance (EPR) spectra confirmed its classification as a cytochrome P450 enzyme. The positive influence of detergents on the enzyme activity is paralleled by a spin state transition of the heme Fe(III) from low to high spin. EPR and CD spectra showed that detergents induce a subtle conformational change, which might result in improved substrate binding. Because hydroperoxide lyase is thought to be a membrane bound protein and detergents mimic a membrane environment, the more active, high spin form likely represents the in vivo conformation. Furthermore, the spin state appeared to be temperature-dependent, with the low spin state favored at low temperature. Point mutants of the highly conserved cysteine in domain D indicated that this residue might be involved in heme binding.

  16. Detergent alkaline proteases: enzymatic properties, genes, and crystal structures.

    PubMed

    Saeki, Katsuhisa; Ozaki, Katsuya; Kobayashi, Tohru; Ito, Susumu

    2007-06-01

    Subtilisin-like serine proteases from bacilli have been used in various industrial fields worldwide, particularly in the production of laundry and automatic dishwashing detergents. They belong to family A of the subtilase superfamily, which is composed of three clans, namely, true subtilisins, high-alkaline proteases, and intracellular proteases. We succeeded in the large-scale production of a high-alkaline protease (M-protease) from alkaliphilic Bacillus clausii KSM-K16, and the enzyme has been introduced into compact heavy-duty laundry detergents. We have also succeeded in the industrial-scale production of a new alkaline protease, KP-43, which was originally resistant to chemical oxidants and to surfactants, produced by alkaliphilic Bacillus sp. strain KSM-KP43 and have incorporated it into laundry detergents. KP-43 and related proteases form a new clan, oxidatively stable proteases, in subtilase family A. In this review, we describe the enzymatic properties, gene sequences, and crystal structures of M-protease, KP-43, and related enzymes.

  17. Orientation of surfactant self-assembled aggregates on graphite

    NASA Astrophysics Data System (ADS)

    Sammalkorpi, Maria; Hynninen, Antti-Pekka; Panagiotopoulos, Athanassios Z.; Haataja, Mikko

    2007-03-01

    Micellar aggregates on surfaces can provide a self-healing corrosion protection or lubrication layer. It has been observed experimentally that on a single crystal surface this layer often consists of oriented hemi-cylindrical micelles which are aligned with the underlying crystal lattice (``orientation effect''). A key feature of this self-assembly process is the interplay between detergent--detergent and detergent--surface interactions. Since the dimensions of the detergent molecules and the unit cell of the surface are typically quite different, the origins of this orientation effect remain unclear. Here we address the question and present the results of Molecular Dynamics simulations of sodium dodecyl sulfate (SDS) self-aggregation on graphite. We employ both single-molecule and multi-molecule simulations of SDS to unravel the origins of the orientation effect. We report that the underlying graphite surface is sufficient to impose orientational bias on individual SDS molecules diffusing on the surface. This produces collective effects that give rise to the oriented hemi-micelles.

  18. Glycosaminoglycan-resistant and pH-sensitive lipid-coated DNA complexes produced by detergent removal method.

    PubMed

    Lehtinen, Julia; Hyvönen, Zanna; Subrizi, Astrid; Bunjes, Heike; Urtti, Arto

    2008-10-21

    Cationic polymers are efficient gene delivery vectors in in vitro conditions, but these carriers can fail in vivo due to interactions with extracellular polyanions, i.e. glycosaminoglycans (GAG). The aim of this study was to develop a stable gene delivery vector that is activated at the acidic endosomal pH. Cationic DNA/PEI complexes were coated by 1,2-dioleylphosphatidylethanolamine (DOPE) and cholesteryl hemisuccinate (CHEMS) (3:2 mol/mol) using two coating methods: detergent removal and mixing with liposomes prepared by ethanol injection. Only detergent removal produced lipid-coated DNA complexes that were stable against GAGs, but were membrane active at low pH towards endosome mimicking liposomes. In relation to the low cellular uptake of the coated complexes, their transfection efficacy was relatively high. PEGylation of the coated complexes increased their cellular uptake but reduced the pH-sensitivity. Detergent removal was thus a superior method for the production of stable, but acid activatable, lipid-coated DNA complexes.

  19. Conformational thermostabilization of the β1-adrenergic receptor in a detergent-resistant form

    PubMed Central

    Serrano-Vega, Maria J.; Magnani, Francesca; Shibata, Yoko; Tate, Christopher G.

    2008-01-01

    There are ≈350 non-odorant G protein-coupled receptors (GPCRs) encoded by the human genome, many of which are predicted to be potential therapeutic targets, but there are only two structures available to represent the whole of the family. We hypothesized that improving the detergent stability of these receptors and simultaneously locking them into one preferred conformation will greatly improve the chances of crystallization. We developed a generic strategy for the isolation of detergent-solubilized thermostable mutants of a GPCR, the β1-adrenergic receptor. The most stable mutant receptor, βAR-m23, contained six point mutations that led to an apparent Tm 21°C higher than the native protein, and, in the presence of bound antagonist, βAR-m23 was as stable as bovine rhodopsin. In addition, βAR-m23 was significantly more stable in a wide range of detergents ideal for crystallization and was preferentially in an antagonist conformation in the absence of ligand. PMID:18192400

  20. Anisotropy Changes of a Fluorescent Probe during the Micellar Growth and Clouding of a Nonionic Detergent.

    PubMed

    Komaromy-Hiller; von Wandruszka R

    1996-01-15

    The effects of temperature and Triton X-114 (TX-114) concentration on the fluorescence anisotropy of perylene were investigated before and after detergent clouding. The measured anisotropy values were used to estimate the microviscosity of the micellar interior. In the lower detergent concentration range, an anisotropy maximum was observed at the critical micelle concentration (CMC), while the values decreased in the range immediately above the CMC. This was ascribed to the micellar volume increase, which, in the case of TX-114, was not accompanied by a more ordered internal environment. A gradual decrease of anisotropy and microviscosity with increasing temperature below the cloud point was observed. At the cloud point, no abrupt changes were found to occur. Compared to detergents with more flexible hydrophobic moieties, TX-114 micelles have a relatively ordered micellar interior indicated by the microviscosity and calculated fusion energy values. In the separated micellar phase formed after clouding, the probe anisotropy increased as water was eliminated at higher temperatures.

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

    PubMed

    Roubalova, Lenka; Vosahlikova, Miroslava; Brejchova, Jana; Sykora, Jan; Rudajev, Vladimir; Svoboda, Petr

    2015-01-01

    HEK293 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. Limited 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.

  2. Effects of soap and detergents on skin surface pH, stratum corneum hydration and fat content in infants.

    PubMed

    Gfatter, R; Hackl, P; Braun, F

    1997-01-01

    In adults the influence of cleansing preparations on the pH, fat content and hydration of the skin is well documented. Studies in newborn and small infants have not been reported. Our study aimed at examining whether similar effects can be ascertained in infants. Infants without skin disease, aged 2 weeks to 16 months, entered an open, controlled and randomized study. Ten infants each had skin washed with tap water (control group), liquid detergent (pH 5.5), compact detergent (pH 5.5) or alkaline soap (pH 9.5). The pH, fat content and hydration were measured before and 10 min after cleansing. Findings were statistically evaluated by parametric covariance analysis. The skin pH increased from an average of 6.60 after cleansing in all groups. The smallest increase (+0.19) was observed in the control group, the largest (+0.45) after washing with alkaline soap. After treatment with liquid or compact detergent, the increase of the pH was only 0.09 higher than for the control group. In comparison to the compact and liquid detergents, the alkaline soap group had a significantly higher increase in pH. The fat content (mean starting value: 4.34 micrograms/cm2) decreased after washing in all groups; the smallest effect was observed in the control group (decrease of 0.93 micrograms/cm2), the highest for the alkaline soap group (decrease of 4.81 micrograms/cm2). In comparison to the compact and liquid detergents, the alkaline soap group had a higher decrease in fat content. This difference was significant for compact detergents. No statistically significant differences were observed for hydration before versus after washing. Each cleansing agent, even normal tap water, influences the skin surface. The increase of the skin pH irritates the physiological protective 'acid mantle', changes the composition of the cutaneous bacterial flora and the activity of enzymes in the upper epidermis, which have an acid pH optimum. The dissolution of fat from the skin surface may influence the hydration status leading to a dry and squamous skin.

  3. Self-contained, single-use hose and tubing cleaning module

    NASA Technical Reports Server (NTRS)

    Rollins, Fred P. (Inventor); Glass, James S. (Inventor)

    1987-01-01

    A self contained, single use hose and tubing cleaning module which utilizes available water supplies without requiring access to precision cleaning facilities is presented. The module is attached to the water source at the inlet side and to the hose or tubing to be cleaned at the outlet side. The water flows through a water purification zone, a detergent dispensing zone, a filtration zone before the detergent laden water flows into the tubing to clean the tubing walls. The module contains an embedded pad which is impregnated with a pH indicator to indicate to the user when the detergent has dissolved and rinsing of the tubing begins.

  4. Solution structure of detergent micelles at conditions relevant to membrane protein crystallization.

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Littrell, K.; Thiyagarajan, P.; Tiede, D.

    1999-07-02

    In this study small angle neutron scattering was used to characterize the formation of micelles in aqueous solutions of the detergents DMG and SPC as a function of detergent concentration and ionic strength of the solvent. The effects on the micelle structure of the additives glycerol and PEG, alone as well as in combination typical for actual membrane protein crystallization, were also explored. This research suggests that the micelles are cigar-like in form at the concentrations studied. The size of the micelles was observed to increase with increasing ionic strength but decrease with the addition of glycerol or PEG.

  5. 40 CFR 80.162 - Additive compositional data.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 16 2011-07-01 2011-07-01 false Additive compositional data. 80.162... (CONTINUED) REGULATION OF FUELS AND FUEL ADDITIVES Detergent Gasoline § 80.162 Additive compositional data... gasoline detergency requirements of this subpart, the compositional data to be supplied to EPA by the...

  6. 40 CFR 80.162 - Additive compositional data.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 17 2013-07-01 2013-07-01 false Additive compositional data. 80.162... (CONTINUED) REGULATION OF FUELS AND FUEL ADDITIVES Detergent Gasoline § 80.162 Additive compositional data... gasoline detergency requirements of this subpart, the compositional data to be supplied to EPA by the...

  7. 40 CFR 80.162 - Additive compositional data.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 16 2010-07-01 2010-07-01 false Additive compositional data. 80.162... (CONTINUED) REGULATION OF FUELS AND FUEL ADDITIVES Detergent Gasoline § 80.162 Additive compositional data... gasoline detergency requirements of this subpart, the compositional data to be supplied to EPA by the...

  8. 40 CFR 80.162 - Additive compositional data.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 17 2012-07-01 2012-07-01 false Additive compositional data. 80.162... (CONTINUED) REGULATION OF FUELS AND FUEL ADDITIVES Detergent Gasoline § 80.162 Additive compositional data... gasoline detergency requirements of this subpart, the compositional data to be supplied to EPA by the...

  9. 40 CFR 80.162 - Additive compositional data.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 17 2014-07-01 2014-07-01 false Additive compositional data. 80.162... (CONTINUED) REGULATION OF FUELS AND FUEL ADDITIVES Detergent Gasoline § 80.162 Additive compositional data... gasoline detergency requirements of this subpart, the compositional data to be supplied to EPA by the...

  10. Dodecyl Maltopyranoside Enabled Purification of Active Human GABA Type A Receptors for Deep and Direct Proteomic Sequencing*

    PubMed Central

    Zhang, Xi; Miller, Keith W.

    2015-01-01

    The challenge in high-quality membrane proteomics is all about sample preparation prior to HPLC, and the cell-to-protein step poses a long-standing bottleneck. Traditional protein extraction methods apply ionic or poly-disperse detergents, harsh denaturation, and repeated protein/peptide precipitation/resolubilization afterward, but suffer low yield, low reproducibility, and low sequence coverage. Contrary to attempts to subdue, we resolved this challenge by providing proteins nature-and-activity-promoting conditions throughout preparation. Using 285-kDa hetero-pentameric human GABA type A receptor overexpressed in HEK293 as a model, we describe a n-dodecyl-β-d-maltopyranoside/cholesteryl hemisuccinate (DDM/CHS)-based affinity purification method, that produced active receptors, supported protease activity, and allowed high performance with both in-gel and direct gel-free proteomic analyses—without detergent removal. Unlike conventional belief that detergents must be removed before HPLC MS, the high-purity low-dose nonionic detergent DDM did not interfere with peptides, and obviated removal or desalting. Sonication or dropwise addition of detergent robustly solubilized over 90% of membrane pellets. The purification conditions were comparable to those applied in successful crystallizations of most membrane proteins. These results enabled streamlined proteomics of human synaptic membrane proteins, and more importantly, allowed directly coupling proteomics with crystallography to characterize both static and dynamic structures of membrane proteins in crystallization pipelines. PMID:25473089

  11. Study of the efficiency of moving bed biofilm reactor (MBBR) in LAS Anionic Detergent removal from hospital wastewater: determination of removing model according to response surface methodology (RSM).

    PubMed

    Shokoohi, Reza; Torkshavand, Zahra; Zolghadnasab, Hassan; Alikhani, Mohammad Yousef; Hemmat, Meisam Sedighi

    2017-04-01

    Detergents are considered one of the important pollutants in hospital wastewater. Achieving efficient and bio-friendly methods for the removal of these pollutants is considered as a concern for environmental researchers. This study aims at studying the efficiency of a moving bed biofilm reactor (MBBR) system for removing linear alkyl benzene sulfonate (LAS) from hospital wastewater with utilization of response surface methodology (RSM). The present study was carried out on a reactor with continuous hydraulic flow using media k 1 at pilot scale to remove detergent from hospital wastewater. The effect of independent variables including contact time, percentage of media filling and mixed liquor suspended solids (MLSS) concentration of 1000-3000 mg/l on the system efficiency were assessed. Methylene blue active substances (MBAS) and chemical oxygen demand (COD) 750-850 mg/l were used by closed laboratory method in order to measure the concentration of LAS. The results revealed that the removal efficiency of LAS detergent and COD using media k 1 , retention time of 24 hours, and MLSS concentration of around 3,000 mg/l were 92.3 and 95.8%, respectively. The results showed that the MBBR system as a bio-friendly compatible method has high efficiency in removing detergents from hospital wastewater and can achieve standard output effluent in acceptable time.

  12. Action on ileal smooth muscle of synthetic detergents and pardaxin.

    PubMed

    Primor, N

    1986-01-01

    Pardaxin (PX), a toxic and repellent substance isolated from the Red Sea flatfish, causes a sharp ball-like profile of drop of saline placed on a hydrophobic film to turn into a flattened one. This effect results with a decrease of the contact angle (theta) from 96 degrees to a maximum of 42 degrees at 10(-4) M of PX. The action of sodium dodecyl sulphate (SDS), a synthetic anionic detergent, benzalkonium chloride (BAC) cationic detergent and pardaxin (PX) a toxic protein with detergent properties, were studied in the ileal guinea-pig longitudinal smooth muscle preparation. SDS (4 X 10(-4) M) and PX (5 X 10(-6) M) diminished the muscle contractile response to field stimulation (0.1 Hz, 1 msec) and to acetylcholine (Ach) and to histamine and elicited a prolonged (4-6 min) TTX-insensitive muscle contraction. The dose dependence of muscle contraction to SDS and PX was found to be sigmoidal and occurred over a narrow range of concentrations. The SDS- but not PX-induced muscle contraction could be reduced by diphenhydramine (H1 antihistamine). BAC (10(-5)-10(-4) M) suppressed the muscle's contractile response to electrical stimulation (0.1 Hz, 1 msec), to Ach, histamine and 5-hydroxytryptamine but did not produce muscle contraction. PX at concentrations higher than 5 X 10(-6) M is a potent detergent and at this concentration shares several pharmacological similarities with SDS.

  13. Reconstitution of a Kv channel into lipid membranes for structural and functional studies.

    PubMed

    Lee, Sungsoo; Zheng, Hui; Shi, Liang; Jiang, Qiu-Xing

    2013-07-13

    To study the lipid-protein interaction in a reductionistic fashion, it is necessary to incorporate the membrane proteins into membranes of well-defined lipid composition. We are studying the lipid-dependent gating effects in a prototype voltage-gated potassium (Kv) channel, and have worked out detailed procedures to reconstitute the channels into different membrane systems. Our reconstitution procedures take consideration of both detergent-induced fusion of vesicles and the fusion of protein/detergent micelles with the lipid/detergent mixed micelles as well as the importance of reaching an equilibrium distribution of lipids among the protein/detergent/lipid and the detergent/lipid mixed micelles. Our data suggested that the insertion of the channels in the lipid vesicles is relatively random in orientations, and the reconstitution efficiency is so high that no detectable protein aggregates were seen in fractionation experiments. We have utilized the reconstituted channels to determine the conformational states of the channels in different lipids, record electrical activities of a small number of channels incorporated in planar lipid bilayers, screen for conformation-specific ligands from a phage-displayed peptide library, and support the growth of 2D crystals of the channels in membranes. The reconstitution procedures described here may be adapted for studying other membrane proteins in lipid bilayers, especially for the investigation of the lipid effects on the eukaryotic voltage-gated ion channels.

  14. The vesicle-to-micelle transition of phosphatidylcholine vesicles induced by nonionic detergents: effects of sodium chloride, sucrose and urea.

    PubMed

    Walter, A; Kuehl, G; Barnes, K; VanderWaerdt, G

    2000-11-23

    The vesicle-to-micelle transition of egg phosphatidylcholine LUVs induced by octylglucoside was studied in buffers with 0-4 M sodium chloride, sucrose or urea. We used both light scattering and fluorescent probes to follow the lipid-detergent complexes in these buffers. The vesicle-to-micelle transition process was fundamentally the same in each solute. However, the detergent-to-lipid ratio required for micelle formation shifted in ways that depended on the aqueous solute. The partitioning of octylglucoside between the vesicles and the aqueous phase was primarily determined by the change in its critical micelle concentration (cmc) induced by each solute. Specifically, the cmc decreased in high salt and sucrose buffers but increased in high concentrations of urea. Cmc for two additional nonionic detergents, decyl- and dodecyl-maltoside, and three zwittergents (3-12, 3-14 and 3-16) were determined as a function of concentration for each of the solutes. In all cases NaCl and sucrose decreased the solubility of the detergents, whereas urea increased their solubilities. The effects clearly depended on acyl chain length in urea-containing solutions, but this dependence was less clear with increasing NaCl and sucrose concentrations. The contributions of these solutes to solubility and to interfacial interactions in the bilayers, pure and mixed micelles are considered.

  15. An Alkaline Protease from Bacillus pumilus MP 27: Functional Analysis of Its Binding Model toward Its Applications As Detergent Additive.

    PubMed

    Baweja, Mehak; Tiwari, Rameshwar; Singh, Puneet K; Nain, Lata; Shukla, Pratyoosh

    2016-01-01

    A proteolytic strain of Bacillus pumilus MP 27 was isolated from water samples of Southern ocean produced alkaline protease. Since protease production need expensive ingredients, an economically viable process was developed by using low cost carbon source, wheat straw, supplemented with peptone. This protease was active within temperature ranges 10-70°C at pH 9. This process was optimized by response surface methodology using a Box Bekhman design by Design Expert 7.0 software that increased the protease activity to 776.5 U/ml. Moreover, the enzyme was extremely stable at a broad range of temperature and pH retaining 69% of its activity at 50°C and 70% at pH 11. The enzyme exhibited excellent compatibility with surfactants and commercial detergents, showing 87% stability with triton X-100 and 100% stability with Tide commercial detergent. The results of the wash performance analysis demonstrated considerably good de-staining at 50 and 4°C with low supplementation (109 U/ml). Molecular modeling of the protease revealed the presence of serine proteases, subtilase family and serine active site and further docking supported the association of catalytic site with the various substrates. Certainly, such protease can be considered as a good detergent additive in detergent industry with a possibility to remove the stains effectively even in a cold wash.

  16. Characterization of detergent compatible protease from halophilic Virgibacillus sp. CD6.

    PubMed

    Lam, Ming Quan; Nik Mut, Nik Nurhidayu; Thevarajoo, Suganthi; Chen, Sye Jinn; Selvaratnam, Chitra; Hussin, Huszalina; Jamaluddin, Haryati; Chong, Chun Shiong

    2018-02-01

    A halophilic bacterium, Virgibacillus sp. strain CD6, was isolated from salted fish and its extracellular protease was characterized. Protease production was found to be highest when yeast extract was used as nitrogen source for growth. The protease exhibited stability at wide range of salt concentration (0-12.5%, w/v), temperatures (20-60 °C), and pH (4-10) with maximum activity at 10.0% (w/v) NaCl, 60 °C, pH 7 and 10, indicating its polyextremophilicity. The protease activity was enhanced in the presence of Mg 2+ , Mn 2+ , Cd 2+ , and Al 3+ (107-122% relative activity), and with retention of activity > 80% for all of other metal ions examined (K + , Ca 2+ , Cu 2+ , Co 2+ , Ni 2+ , Zn 2+ , and Fe 3+ ). Both PMSF and EDTA inhibited protease activity, denoting serine protease and metalloprotease properties, respectively. High stability (> 70%) was demonstrated in the presence of organic solvents and detergent constituents, and the extracellular protease from strain CD6 was also found to be compatible in commercial detergents. Proteinaceous stain removal efficacy revealed that crude protease of strain CD6 could significantly enhance the performance of commercial detergent. The protease from Virgibacillus sp. strain CD6 could serve as a promising alternative for various applications, especially in detergent industry.

  17. Characterisation of a detergent-stable alkaline protease from a novel thermophilic strain Paenibacillus tezpurensis sp. nov. AS-S24-II.

    PubMed

    Rai, Sudhir K; Roy, Jetendra K; Mukherjee, Ashis K

    2010-02-01

    An alkaline-protease-producing bacterial strain (AS-S24-II) isolated from a soil sample in Assam is a Gram-stain-positive, catalase-positive, endospore-forming rod and grows at temperatures ranging from 30 degrees C to 60 degrees C and salinity ranging from 0% to 7% (w/v) NaCl. Phenotypic characterisation, chemotaxonomic properties, presence of Paenibacillus-specific signature sequences, and ribotyping data suggested that the strain AS-S24-II represents a novel species of the genus Paenibacillus, for which the name Paenibacillus tezpurensis sp. nov. (MTCC 8959) is proposed. Phylogenetic analysis revealed that P. lentimorbus strain DNG-14 and P. lentimorbus strain DNG-16 represent the closest phylogenetic neighbour of this novel strain. Alkaline protease production (598 x 10(3) U l(-1)) by P. tezpurensis sp. nov. in SmF was optimised by response surface method. A laundry-detergent-stable, Ca(2+)-independent, 43-kDa molecular weight alkaline serine protease from this strain was purified with a 1.7-fold increase in specific activity. The purified protease displayed optimum activity at pH 9.5 and 45-50 degrees C temperature range and exhibited a significant stability and compatibility with surfactants and most of the tested commercial laundry detergents at room temperature. Further, the protease improved the wash performance of detergents, thus demonstrating its feasibility for inclusion in laundry detergent formulations.

  18. A newly high alkaline lipase: an ideal choice for application in detergent formulations

    PubMed Central

    2011-01-01

    Background Bacterial lipases received much attention for their substrate specificity and their ability to function in extreme environments (pH, temperature...). Many staphylococci produced lipases which were released into the culture medium. Reports of thermostable lipases from Staphylococcus sp. and active in alkaline conditions are not previously described. Results A newly soil-isolated Staphylococcus sp. strain ESW secretes an induced lipase in the culture medium. The effects of temperature, pH and various components in a detergent on the activity and stability of Staphylococcus sp. lipase (SL1) were studied in a preliminary evaluation for use in detergent formulation solutions. The enzyme was highly active over a wide range of pH from 9.0 to 13.0, with an optimum at pH 12.0. The relative activity at pH 13.0 was about 60% of that obtained at pH 12.0. It exhibited maximal activity at 60°C. This novel lipase, showed extreme stability towards non-ionic and anionic surfactants after pre-incubation for 1 h at 40°C, and relative stability towards oxidizing agents. Additionally, the crude enzyme showed excellent stability and compatibility with various commercial solid and liquid detergents. Conclusions These properties added to the high activity in high alkaline pH make this novel lipase an ideal choice for application in detergent formulations. PMID:22123072

  19. Identification of conserved lipid/detergent-binding sites in a high-resolution structure of the membrane protein cytochrome c oxidase

    PubMed Central

    Qin, Ling; Hiser, Carrie; Mulichak, Anne; Garavito, R. Michael; Ferguson-Miller, Shelagh

    2006-01-01

    Well ordered reproducible crystals of cytochrome c oxidase (CcO) from Rhodobacter sphaeroides yield a previously unreported structure at 2.0 Å resolution that contains the two catalytic subunits and a number of alkyl chains of lipids and detergents. Comparison with crystal structures of other bacterial and mammalian CcOs reveals that the positions occupied by native membrane lipids and detergent substitutes are highly conserved, along with amino acid residues in their vicinity, suggesting a more prevalent and specific role of lipid in membrane protein structure than often envisioned. Well defined detergent head groups (maltose) are found associated with aromatic residues in a manner similar to phospholipid head groups, likely contributing to the success of alkyl glycoside detergents in supporting membrane protein activity and crystallizability. Other significant features of this structure include the following: finding of a previously unreported crystal contact mediated by cadmium and an engineered histidine tag; documentation of the unique His–Tyr covalent linkage close to the active site; remarkable conservation of a chain of waters in one proton pathway (D-path); and discovery of an inhibitory cadmium-binding site at the entrance to another proton path (K-path). These observations provide important insight into CcO structure and mechanism, as well as the significance of bound lipid in membrane proteins. PMID:17050688

  20. Effect of soaps and detergents on epidermal barrier function.

    PubMed

    Wolf, Ronni; Parish, Lawrence Charles

    2012-01-01

    The past decade has witnessed an explosion of new impartial information about the complex interaction of the skin with topically applied substances, including soaps and detergents. Despite of all these new data, our knowledge on the exact pathomechanism and molecular events leading to detergent-induced barrier dysfunction remains incomplete and the answers continue to elude us. The longtime prevailing opinion which contends that the damaging effect of soaps and detergents is related to their property to extract and remove useful intercellular lipids has mostly been abandoned. Although this effect might be involved in the damaging effect, it is definitely not the sole mechanism, nor, indeed, is it even the main one. Skin proteins damage, the interaction with keratins and their denaturation, swelling of cell membranes and collagen fibers, cytotoxicity expressed with cellular lysis are other important mechanisms. One proposed mechanism is that an initial stratum corneum hyper-hydration results from a continuous disruption of the secondary and tertiary structures of keratin protein by surfactants, exposing new water-binding sites, thereby increasing the hydration of the membrane. Following evaporation of excess water, the denatured keratin possesses a decreased water-binding capacity and decreased ability to function as a barrier. Recent studies have also emphasized the effects of detergents on lipid synthesis, on lipid-metabolizing enzymes and on keratinocyte differentiation. Copyright © 2012 Elsevier Inc. All rights reserved.

  1. 40 CFR 80.165 - Certification test procedures and standards.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... PROGRAMS (CONTINUED) REGULATION OF FUELS AND FUEL ADDITIVES Detergent Gasoline § 80.165 Certification test... detergent additive is mixed in a test fuel meeting all relevant requirements of § 80.164, including the... for such records. (a) Fuel injector deposit control testing. (1) The required test fuel must produce...

  2. 40 CFR 80.165 - Certification test procedures and standards.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... PROGRAMS (CONTINUED) REGULATION OF FUELS AND FUEL ADDITIVES Detergent Gasoline § 80.165 Certification test... detergent additive is mixed in a test fuel meeting all relevant requirements of § 80.164, including the... for such records. (a) Fuel injector deposit control testing. (1) The required test fuel must produce...

  3. Effect of urea and urea-gamma treatments on cellulose degradation of Thai rice straw and corn stalk

    NASA Astrophysics Data System (ADS)

    Banchorndhevakul, Siriwattana

    2002-08-01

    Cellulose degradation of 20% urea treated and 20% urea-10 kGy gamma treated Thai rice straw and corn stalk showed that combination effect of urea and gamma radiation gave a higher % decrease in neutral detergent fiber (NDF), acid detergent fiber (ADF), acid detergent lignin (ADL), cellulose, hemicellulose, and lignin and cutin in comparison with urea effect only for both room temperature storage and room temperature +258 K storage. The results also indicated that cellulose degradation proceeded with time, even at 258 K. A drastic drop to less than half of the original contents in NDF, ADF, and ADL could not be obtained in this study.

  4. Ingestion of Laundry Detergent Packets in Children.

    PubMed

    Shah, Lindsey Wilson

    2016-08-01

    Ingestion of laundry detergent packets is an important threat to young children. Because of their developmental stage, toddlers are prone to place these small, colorful packets in their mouths. The packets can easily burst, sending a large volume of viscous, alkaline liquid throughout the oropharynx. Ingestion causes major toxic effects, including depression of the central nervous system, metabolic acidosis, respiratory distress, and dysphagia. Critical care nurses should anticipate these clinical effects and facilitate prompt intervention. Increased understanding of the risks and clinical effects of ingestion of laundry detergent packets will better prepare critical care nurses to provide care for these children. (Critical Care Nurse 2016; 36[4]:70-75). ©2016 American Association of Critical-Care Nurses.

  5. Detergent Stabilized Nanopore Formation Kinetics of an Anthrax Protein

    NASA Astrophysics Data System (ADS)

    Peterson, Kelby

    2015-03-01

    This summer research project funded through the Society of Physics Students Internship Program and The National Institute of Standards and Technology focused on optimization of pore formation of Protective Antigen protein secreted by Bacillus Anthraces. This experiment analyzes the use of N-tetradecylphosphocholine (FOS-14 Detergent) to stabilize the water soluble protein, protective antigen protein (PA63) to regulate the kinetics of pore formation in a model bilayer lipid membrane. The FOS-14 Detergent was tested under various conditions to understand its impact on the protein pore formation. The optimization of this channel insertion is critical in preparing samples of oriented for neutron reflectometry that provide new data to increase the understanding of the protein's structure.

  6. 77 FR 31443 - Energy Conservation Program: Test Procedures for Residential Dishwashers, Dehumidifiers, and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-25

    ... dishwashers with a separate soil- sensing cycle, and the normal cycle definition, power supply and detergent... Soiling Requirements 5. Detergent Dosing Specifications E. Incorporation by Reference of an Updated AHAM...: (1) The addition of a method to rate the efficiency of soil-sensing products; (2) the addition of a...

  7. Biomass Compositional Analysis Laboratory Procedures | Bioenergy | NREL

    Science.gov Websites

    Compositional Analysis This procedure describes methods for sample drying and size reduction, obtaining samples methods used to determine the amount of solids or moisture present in a solid or slurry biomass sample as values? We have found that neutral detergent fiber (NDF) and acid detergent fiber (ADF) methods report

  8. 40 CFR 80.161 - Detergent additive certification program.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... corresponding test results (percent flow restriction demonstrated in the PFID test and milligrams of deposit per... penalties in §§ 80.169 and 80.172. (iii) If both parties submit the required information, EPA will evaluate... customers who use the disqualified detergent. Failure to do so may subject the certifier to liabilities for...

  9. Cheyenne-Laramie County Economic Development Strategy

    DTIC Science & Technology

    1986-06-01

    Industry SIC 2879 4. Cosmetics and Toilet Preparations Industry SIC 2844 5. Electronic Connectors Industry SIC 3678 6. Mineral Wool Industry SIC 3296...five primary target-industries selected are: Soap and Other Detergents, Toilet Preparations, Agricultural Chemicals, Mineral Wool , and Electronic...Cheyenne include: -- soap and other detergents -- toilet preparation -- agricultural chemicals -- mineral wool -- electronic connectors * downtown

  10. A Lab Experience to Illustrate the Physicochemical Principles of Detergency

    ERIC Educational Resources Information Center

    Poce-Fatou, J. A.; Bethencourt-Nunez, M.; Moreno, C.; Pinto-Ganfornina, J. J.; Moreno-Dorado, F. J.

    2008-01-01

    This article presents a lab experience to study detergency from a physicochemical point of view intended for undergraduate students. By means of a simple experimental device, we analyze the influence of the surfactant concentration in both distilled water and tap water. Our method is based on the measurement of diffuse reflectances of polyester…

  11. Canopy visible and near-infrared reflectance data to estimate alfalfa nutritive attributes before harvest

    USDA-ARS?s Scientific Manuscript database

    Proximal sensing could help improve profit margins by timing the cutting or harvesting of alfalfa (Medicago sativa L.), in rapid assessment of nutritive values, such as total nitrogen (N), neutral detergent fiber (NDF), and acid detergent fiber (ADF) as well as nutritive quality indicators such as r...

  12. A ring test of in vitro neutral detergent fiber digestibility: analytical variability and sample ranking

    USDA-ARS?s Scientific Manuscript database

    In vitro neutral detergent fiber (NDF) digestibility (NDFD) is an empirical measurement used to describe fermentability of NDF by rumen microbes. Variability is inherent in assays and affects the precision that can be expected for replicated samples. The study objective was to evaluate variability w...

  13. A ring test of in vitro neutral detergent fiber digestibility: Analytical variability and sample ranking

    USDA-ARS?s Scientific Manuscript database

    In vitro neutral detergent fiber (NDF) digestibility (NDFD) is an empirical measurement used to describe fermentability of NDF by rumen microbes. Variability is inherent in assays and affects the precision that can be expected for replicated samples. The study objective was to evaluate variability w...

  14. A Class of Rigid Linker-bearing Glucosides for Membrane Protein Structural Study.

    PubMed

    Sadaf, Aiman; Mortensen, Jonas S; Capaldi, Stefano; Tikhonova, Elena; Hariharan, Parameswaran; de Castro Ribeiro, Orquidea; Loland, Claus J; Guan, Lan; Byrne, Bernadette; Chae, Pil Seok

    2016-03-01

    Membrane proteins are amphipathic bio-macromolecules incompatible with the polar environments of aqueous media. Conventional detergents encapsulate the hydrophobic surfaces of membrane proteins allowing them to exist in aqueous solution. Membrane proteins stabilized by detergent micelles are used for structural and functional analysis. Despite the availability of a large number of detergents, only a few agents are sufficiently effective at maintaining the integrity of membrane proteins to allow successful crystallization. In the present study, we describe a novel class of synthetic amphiphiles with a branched tail group and a triglucoside head group. These head and tail groups were connected via an amide or ether linkage by using a tris(hydroxylmethyl)aminomethane (TRIS) or neopentyl glycol (NPG) linker to produce TRIS-derived triglucosides (TDTs) and NPG-derived triglucosides (NDTs), respectively. Members of this class conferred enhanced stability on target membrane proteins compared to conventional detergents. Because of straightforward synthesis of the novel agents and their favourable effects on a range of membrane proteins, these agents should be of wide applicability to membrane protein science.

  15. Effect of detergents, trypsin and unsaturated fatty acids on latent loquat fruit polyphenol oxidase: basis for the enzyme's activity regulation.

    PubMed

    Sellés-Marchart, Susana; Casado-Vela, Juan; Bru-Martínez, Roque

    2007-08-15

    The effects of detergents, trypsin and fatty acids on structural and functional properties of a pure loquat fruit latent polyphenol oxidase have been studied in relation to its regulation. Anionic detergents activated PPO at pH 6.0 below critical micelle concentration (cmc), but inhibited at pH 4.5 well above cmc. This behavior is due to a detergent-induced pH profile alkaline shift, accompanied by changes of intrinsic fluorescence of the protein. Gel filtration experiments demonstrate the formation of PPO-SDS mixed micelles. Partial PPO proteolysis suggest that latent PPO losses an SDS micelle-interacting region but conserves an SDS monomer-interacting site. Unsaturated fatty acids inhibit PPO at pH 4.5, the strongest being linolenic acid while the weakest was gamma-linolenic acid for both, the native and the trypsin-treated PPO. Down-regulation of PPO activity by anionic amphiphiles is discussed based on both, the pH profile shift induced upon anionic amphiphile binding and the PPO interaction with negatively charged membranes.

  16. Tonoplast of Beta vulgaris L. contains detergent-resistant membrane microdomains.

    PubMed

    Ozolina, Natalia V; Nesterkina, Irina S; Kolesnikova, Ekaterina V; Salyaev, Ryurik K; Nurminsky, Vadim N; Rakevich, Alexander L; Martynovich, Evgueni F; Chernyshov, Michael Yu

    2013-03-01

    The experiments conducted on tonoplast of Beta vulgaris L. roots were performed to identify detergent-resistant lipid-protein microdomains (DRMs, interpreted as lipid rafts).The presence of DRMs can be found when dynamic clustering of sphingolipids, sterols, saturated fatty acids is registered, and the insolubility of these microdomains in nonionic detergents at low temperatures is proven. The elucidation of tonoplast microdomains has been based on results obtained with the aid of high-speed centrifuging in the sucrose gradient. The experiments have shown that tonoplast microdomains are rich in sphingolipids, free sterols and saturated fatty acids (such a lipid content is also typical of lipid-protein microdomains of other membranes), while only few phospholipids are present in tonoplast microdomains. The presence of microdomains has been confirmed by fluorescence and confocal microscopy using filipin and Laurdan as fluorescent probes. The experiments with Laurdan have shown that tonoplast microdomains are characterized by a high order compared to characteristics of the rest of the tonoplast. Thus, the presence of detergent-resistant lipid-protein microdomains in the tonoplast has been demonstrated.

  17. A Class of Rigid Linker-bearing Glucosides for Membrane Protein Structural Study

    PubMed Central

    Sadaf, Aiman; Mortensen, Jonas S.; Capaldi, Stefano; Tikhonova, Elena; Hariharan, Parameswaran; de Castro Ribeiro, Orquidea; Loland, Claus J; Guan, Lan; Byrne, Bernadette

    2015-01-01

    Membrane proteins are amphipathic bio-macromolecules incompatible with the polar environments of aqueous media. Conventional detergents encapsulate the hydrophobic surfaces of membrane proteins allowing them to exist in aqueous solution. Membrane proteins stabilized by detergent micelles are used for structural and functional analysis. Despite the availability of a large number of detergents, only a few agents are sufficiently effective at maintaining the integrity of membrane proteins to allow successful crystallization. In the present study, we describe a novel class of synthetic amphiphiles with a branched tail group and a triglucoside head group. These head and tail groups were connected via an amide or ether linkage by using a tris(hydroxylmethyl)aminomethane (TRIS) or neopentyl glycol (NPG) linker to produce TRIS-derived triglucosides (TDTs) and NPG-derived triglucosides (NDTs), respectively. Members of this class conferred enhanced stability on target membrane proteins compared to conventional detergents. Because of straightforward synthesis of the novel agents and their favourable effects on a range of membrane proteins, these agents should be of wide applicability to membrane protein science. PMID:27110345

  18. Overcoming bottlenecks in the membrane protein structural biology pipeline.

    PubMed

    Hardy, David; Bill, Roslyn M; Jawhari, Anass; Rothnie, Alice J

    2016-06-15

    Membrane proteins account for a third of the eukaryotic proteome, but are greatly under-represented in the Protein Data Bank. Unfortunately, recent technological advances in X-ray crystallography and EM cannot account for the poor solubility and stability of membrane protein samples. A limitation of conventional detergent-based methods is that detergent molecules destabilize membrane proteins, leading to their aggregation. The use of orthologues, mutants and fusion tags has helped improve protein stability, but at the expense of not working with the sequence of interest. Novel detergents such as glucose neopentyl glycol (GNG), maltose neopentyl glycol (MNG) and calixarene-based detergents can improve protein stability without compromising their solubilizing properties. Styrene maleic acid lipid particles (SMALPs) focus on retaining the native lipid bilayer of a membrane protein during purification and biophysical analysis. Overcoming bottlenecks in the membrane protein structural biology pipeline, primarily by maintaining protein stability, will facilitate the elucidation of many more membrane protein structures in the near future. © 2016 The Author(s). published by Portland Press Limited on behalf of the Biochemical Society.

  19. [Rapid and efficient extraction of soluble proteins from gram-negative microorganisms without disruption of cell walls].

    PubMed

    Danilevich, V N; Petrovskaia, L E; Grishin, E V

    2006-01-01

    The ability of buffer solutions containing low concentrations of nonionic detergents (Triton X-100, Tween 20, Brij 58, and Lubrol PX) and the anionic detergent sodium deoxycholate, as well as mixtures of these detergents with chaeotropes (urea and guanidine hydrochloride), to extract intracellular proteins of Gram-negative microorganisms (Escherichia coli and Pseudomonas aeruginosa) was studied. It was established that the solutions containing Triton X-100 and sodium deoxycholate and the mixtures of these detergents with urea are the most effective. It was shown that the extraction of proteins from bacterial cells under the studied conditions is not accompanied by a release of DNA into solution but is associated with extraction of low-molecular RNAs. The level of protein extraction reaches 80%. No disruption of the bacterial cell wall occurs during the extraction, and proteins probably permeate through meshes of the murein network. The efficiencies of our buffer mixtures are close to or higher than that of the commercial reagent CelLytic B (Sigma, United States). The practical uses of the chaeotropic mixtures developed are discussed.

  20. Production of lipase and protease from an indigenous Pseudomonas aeruginosa strain and their evaluation as detergent additives: compatibility study with detergent ingredients and washing performance.

    PubMed

    Grbavčić, Sanja; Bezbradica, Dejan; Izrael-Živković, Lidija; Avramović, Nataša; Milosavić, Nenad; Karadžić, Ivanka; Knežević-Jugović, Zorica

    2011-12-01

    An indigenous Pseudomonas aeruginosa strain has been studied for lipase and protease activities for their potential application in detergents. Produced enzymes were investigated in order to assess their compatibility with several surfactants, oxidizing agents and commercial detergents. The crude lipase appeared to retain high activity and stability in the presence of several surfactants and oxidizing agents and it was insusceptible to proteolysis. Lutensol® XP80 and Triton® X-100 strongly activated the lipase for a long period (up to 40 and 30% against the control after 1h) while the protease activity was enhanced by the addition of Triton® WR1339 and Tween® 80. The washing performance of the investigated surfactants was significantly improved with the addition of the crude enzyme preparation. Studies were further undertaken to improve enzymes production. The optimization of fermentation conditions led to an 8-fold increase of lipase production, while the production of protease was enhanced by 60%. Copyright © 2011 Elsevier Ltd. All rights reserved.

  1. Micro-scale NMR Screening of New Detergents for Membrane Protein Structural Biology

    PubMed Central

    Zhang, Qinghai; Horst, Reto; Geralt, Michael; Ma, Xingquan; Hong, Wen-Xu; Finn, M. G.; Stevens, Raymond C.; Wüthrich, Kurt

    2008-01-01

    The rate limiting step in biophysical characterization of membrane proteins is often the availability of suitable amounts of protein material. It was therefore of interest to demonstrate that micro-coil nuclear magnetic resonance (NMR) technology can be used to screen microscale quantities of membrane proteins for proper folding in samples destined for structural studies. Micoscale NMR was then used to screen a series of newly designed zwitterionic phosphocholine detergents for their ability to reconstitute membrane proteins, using the previously well characterized β-barrel E.coli outer membrane protein OmpX as a test case. Fold screening was thus achieved with μg-amounts of uniformly 2H,15N-labeld OmpX and affordable amounts of the detergents, and prescreening with SDS-gel electrophoresis ensured efficient selection of the targets for NMR studies. A systematic approach to optimize the phosphocholine motif for membrane protein refolding led to the identification of two new detergents, 138-Fos and 179-Fos, that yield 2D [15N,1H]-TROSY correlation NMR spectra of natively folded reconstituted OmpX. PMID:18479092

  2. The safety of synthetic zeolites used in detergents.

    PubMed

    Fruijtier-Pölloth, Claudia

    2009-01-01

    Synthetic zeolites are replacing phosphates as builders in laundry detergents; workers and consumers may, therefore, increasingly be exposed to these materials and it is important to assess their safety. This article puts mechanistic, toxicological and exposure data into context for a safety assessment. Zeolites are hygroscopic compounds with ion-exchanging properties. They may partially decompose under acidic conditions such as in the stomach releasing sodium ions, silicic acid and aluminum salts. The intact molecule is not bioavailable after oral intake or exposure through the dermal and inhalational routes. Under current conditions of manufacture and use, no systemic toxicity is to be expected from neither the intact molecule nor the degradation products; a significant effect on the bioavailability of other compounds is not likely. Zeolites may cause local irritation. It is, therefore, important to minimise occupational exposure. The co-operation of detergent manufacturers with the manufacturers of washing machines is necessary to find the right balance between environmental aspects such as energy and water savings and the occurrence of detergent residues on textiles due to insufficient rinsing.

  3. Detergent Optimized Membrane Protein Reconstitution in Liposomes for Solid State NMR

    PubMed Central

    2015-01-01

    For small helical membrane proteins, their structures are highly sensitive to their environment, and solid state NMR is a structural technique that can characterize these membrane proteins in native-like lipid bilayers and proteoliposomes. To date, a systematic method by which to evaluate the effect of the solubilizing detergent on proteoliposome preparations for solid state NMR of membrane proteins has not been presented in the literature. A set of experiments are presented aimed at determining the conditions most amenable to dialysis mediated reconstitution sample preparation. A membrane protein from M. tuberculosis is used to illustrate the method. The results show that a detergent that stabilizes the most protein is not always ideal and sometimes cannot be removed by dialysis. By focusing on the lipid and protein binding properties of the detergent, proteoliposome preparations can be readily produced, which provide double the signal-to-noise ratios for both the oriented sample and magic angle spinning solid state NMR. The method will allow more membrane protein drug targets to be structurally characterized in lipid bilayer environments. PMID:24665863

  4. Rapid directed evolution of stabilized proteins with cellular high-throughput encapsulation solubilization and screening (CHESS).

    PubMed

    Yong, K J; Scott, D J

    2015-03-01

    Directed evolution is a powerful method for engineering proteins towards user-defined goals and has been used to generate novel proteins for industrial processes, biological research and drug discovery. Typical directed evolution techniques include cellular display, phage display, ribosome display and water-in-oil compartmentalization, all of which physically link individual members of diverse gene libraries to their translated proteins. This allows the screening or selection for a desired protein function and subsequent isolation of the encoding gene from diverse populations. For biotechnological and industrial applications there is a need to engineer proteins that are functional under conditions that are not compatible with these techniques, such as high temperatures and harsh detergents. Cellular High-throughput Encapsulation Solubilization and Screening (CHESS), is a directed evolution method originally developed to engineer detergent-stable G proteins-coupled receptors (GPCRs) for structural biology. With CHESS, library-transformed bacterial cells are encapsulated in detergent-resistant polymers to form capsules, which serve to contain mutant genes and their encoded proteins upon detergent mediated solubilization of cell membranes. Populations of capsules can be screened like single cells to enable rapid isolation of genes encoding detergent-stable protein mutants. To demonstrate the general applicability of CHESS to other proteins, we have characterized the stability and permeability of CHESS microcapsules and employed CHESS to generate thermostable, sodium dodecyl sulfate (SDS) resistant green fluorescent protein (GFP) mutants, the first soluble proteins to be engineered using CHESS. © 2014 Wiley Periodicals, Inc.

  5. Suitability of the isolated chicken eye test for classification of extreme pH detergents and cleaning products.

    PubMed

    Cazelle, Elodie; Eskes, Chantra; Hermann, Martina; Jones, Penny; McNamee, Pauline; Prinsen, Menk; Taylor, Hannah; Wijnands, Marcel V W

    2015-04-01

    A.I.S.E. investigated the suitability of the regulatory adopted ICE in vitro test method (OECD TG 438) with or without histopathology to identify detergent and cleaning formulations having extreme pH that require classification as EU CLP/UN GHS Category 1. To this aim, 18 extreme pH detergent and cleaning formulations were tested covering both alkaline and acidic extreme pHs. The ICE standard test method following OECD Test Guideline 438 showed good concordance with in vivo classification (83%) and good and balanced specificity and sensitivity values (83%) which are in line with the performances of currently adopted in vitro test guidelines, confirming its suitability to identify Category 1 extreme pH detergent and cleaning products. In contrast to previous findings obtained with non-extreme pH formulations, the use of histopathology did not improve the sensitivity of the assay whilst it strongly decreased its specificity for the extreme pH formulations. Furthermore, use of non-testing prediction rules for classification showed poor concordance values (33% for the extreme pH rule and 61% for the EU CLP additivity approach) with high rates of over-prediction (100% for the extreme pH rule and 50% for the additivity approach), indicating that these non-testing prediction rules are not suitable to predict Category 1 hazards of extreme pH detergent and cleaning formulations. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. Isolation and characterization of recombinant murine Wnt3a.

    PubMed

    Witkowski, Andrzej; Krishnamoorthy, Aparna; Su, Betty; Beckstead, Jennifer A; Ryan, Robert O

    2015-02-01

    Wnt proteins are a family of morphogens that possess potent biological activity. Structure-function studies have been impeded by poor yield of biologically active recombinant Wnt as well as a propensity of isolated Wnt to self-associate in the absence of detergent. Using stably transfected Drosophila S2 cells, studies have been conducted to improve recovery of recombinant murine Wnt3a, establish conditions for a detergent-free Wnt preparation and examine the effects of limited proteolysis. S2 cell culture conditioned media was subjected to a 3-step protocol including dye-ligand chromatography, immobilized metal affinity chromatography and gel filtration chromatography. Through selective pooling of column fractions, homogeneous and purified Wnt3a preparations were obtained. Limited proteolysis of Wnt3a with thrombin resulted in site-specific cleavage within the N-terminal saposin-like motif. To generate detergent-free protein, Wnt3a was immobilized on Cu(2+)-charged, iminodiacetic acid-derivatized Sepharose beads, detergent-free buffer was applied and Wnt3a eluted from the beads with buffer containing imidazole plus 30mM methyl-ß-cyclodextrin (MßCD). Wnt3a recovered in MßCD-containing buffer was soluble and biologically active. Insofar as MßCD is a member of a family of non-toxic, low molecular weight compounds capable of binding and solubilizing small hydrophobic ligands, Wnt-cyclodextrin complexes may facilitate structure-activity studies in the absence of adverse detergent effects. Copyright © 2014 Elsevier Inc. All rights reserved.

  7. The in vitro impact of toothpaste extracts on cell viability.

    PubMed

    Cvikl, Barbara; Lussi, Adrian; Gruber, Reinhard

    2015-06-01

    Toothpastes contain three main components: detergents, abrasives, and fluoride. Detergents, particularly sodium lauryl sulfate, have been proposed as components that enable toothpastes to produce cytotoxic effects in vitro. However, not all toothpastes contain sodium lauryl sulfate, and almost no studies have found an association between detergents and the in vitro cytotoxicity of toothpastes. The present study examined the in vitro cytotoxicity of nine commercially available toothpastes containing four different detergents. Toothpastes were diluted in serum-free medium, centrifuged, and filter sterilized. The half-lethal concentration of the toothpaste-conditioned medium (TCM) was calculated based on the formation of formazan by gingival fibroblasts, oral squamous cell carcinoma HSC-2 cells, and L929 cells. Cell proliferation was analyzed, and live-dead staining was performed, after exposure of cells to conditioned medium prepared with 1% toothpaste (1% TCM). It was found that toothpastes containing sodium lauryl sulfate and amine fluoride strongly inhibited cell viability with the half-lethal concentration being obtained with conditioned medium prepared with approximately 1% toothpaste (1% TCM). Toothpastes containing cocamidopropyl betaine and Steareth-20 showed higher half-lethal concentration values, with the half-lethal concentration being obtained with conditioned medium prepared with 10% (10% TCM) and 70% (70% TCM) toothpaste, respectively. Proliferation and live-dead data were consistent with the cell-viability analyses. These results demonstrate that the type of detergent in toothpastes can be associated with changes in in vitro cell toxicity. © 2015 Eur J Oral Sci.

  8. Effect of detergents on the physicochemical properties of skin stratum corneum: a two-photon excitation fluorescence microscopy study.

    PubMed

    Bloksgaard, M; Brewer, J R; Pashkovski, E; Ananthapadmanabhan, K P; Sørensen, J A; Bagatolli, L A

    2014-02-01

    Understanding the structural and dynamical features of skin is critical for advancing innovation in personal care and drug discovery. Synthetic detergent mixtures used in commercially available body wash products are thought to be less aggressive towards the skin barrier when compared to conventional detergents. The aim of this work is to comparatively characterize the effect of a mild synthetic cleanser mixture (SCM) and sodium dodecyl sulphate (SDS) on the hydration state of the intercellular lipid matrix and on proton activity of excised skin stratum corneum (SC). Experiments were performed using two-photon excitation fluorescence microscopy. Fluorescent images of fluorescence reporters sensitive to proton activity and hydration of SC were obtained in excised skin and examined in the presence and absence of SCM and SDS detergents. Hydration of the intercellular lipid matrix to a depth of 10 μm into the SC was increased upon treatment with SCM, whereas SDS shows this effect only at the very surface of SC. The proton activity of SC remained unaffected by treatment with either detergent. While our study indicates that the SC is very resistant to external stimuli, it also shows that, in contrast to the response to SDS, SCM to some extent modulates the in-depth hydration properties of the intercellular lipid matrix within excised skin SC. © 2013 Society of Cosmetic Scientists and the Société Française de Cosmétologie.

  9. Isolation and characterization of recombinant murine Wnt3a

    PubMed Central

    Witkowski, Andrzej; Krishnamoorthy, Aparna; Su, Betty; Beckstead, Jennifer A.; Ryan, Robert O.

    2014-01-01

    Wnt proteins are a family of morphogens that possess potent biological activity. Structure – function studies have been impeded by poor yield of biologically active recombinant Wnt as well as a propensity of isolated Wnt to self-associate in the absence of detergent. Using stably transfected Drosophila S2 cells, studies have been conducted to improve recovery of recombinant murine Wnt3a, establish conditions for a detergent-free Wnt preparation and examine the effects of limited proteolysis. S2 cell culture conditioned media was subjected to a 3-step protocol including dye-ligand chromatography, immobilized metal affinity chromatography and gel filtration chromatography. Through selective pooling of column fractions, homogeneous and purified Wnt3a preparations were obtained. Limited proteolysis of Wnt3a with thrombin resulted in site-specific cleavage within the N-terminal saposin-like motif. To generate detergent-free protein, Wnt3a was immobilized on Cu2+-charged, iminodiacetic acid-derivatized Sepharose beads, detergent-free buffer was applied and Wnt3a eluted from the beads with buffer containing imidazole plus 30 mM methyl-β-cyclodextrin (MβCD). Wnt3a recovered in MβCD-containing buffer was soluble and biologically active. Insofar as MβCD is a member of a family of non-toxic, low molecular weight compounds capable of binding and solubilizing small hydrophobic ligands, Wnt-cyclodextrin complexes may facilitate structure-activity studies in the absence of adverse detergent effects. PMID:25448592

  10. Apo AI/ABCA1-dependent and HDL3-mediated lipid efflux from compositionally distinct cholesterol-based microdomains.

    PubMed

    Drobnik, Wolfgang; Borsukova, Hana; Böttcher, Alfred; Pfeiffer, Alexandra; Liebisch, Gerhard; Schütz, Gerhard J; Schindler, Hansgeorg; Schmitz, Gerd

    2002-04-01

    We have investigated whether a raft heterogeneity exists in human monocyte-derived macrophages and fibroblasts and whether these microdomains are modulated by lipid efflux. Triton X-100 (Triton) or Lubrol WX (Lubrol) detergent-resistant membranes from cholesterol-loaded monocytes were associated with the following findings: (i) Lubrol-DRM contained most of the cellular cholesterol and at least 75% of Triton-detergent-resistant membranes. (ii) 'Lubrol rafts', defined by their solubility in Triton but insolubility in Lubrol, were enriched in unsaturated phosphatidylcholine and showed a lower cholesterol to choline-phospholipid ratio compared to Triton rafts. (iii) CD14 and CD55 were recovered in Triton- and Lubrol-detergent-resistant membranes, whereas CD11b was found exclusively in Triton DRM. ABCA1 implicated in apo AI-mediated lipid efflux and CDC42 were partially localized in Lubrol- but not in Triton-detergent-resistant membranes. (iv) Apo AI preferentially depleted cholesterol and choline-phospholipids from Lubrol rafts, whereas HDL3 additionally decreased the cholesterol content of Triton rafts. In fibroblasts, neither ABCA1 nor CDC42 was found in Lubrol rafts, and both apo AI and HDL3 reduced the lipid content in Lubrol- as well as in Triton-detergent-resistant membranes. In summary, we provide evidence for the existence of compositionally distinct membrane microdomains in human cells and their modulation by apo AI/ABCA1-dependent and HDL3-mediated lipid efflux.

  11. Molecular features of nonionic detergents involved in the binding kinetics and solubilization efficiency, as studied in model (Langmuir films) and biological (Erythrocytes) membranes.

    PubMed

    Casadei, Bruna Renata; Domingues, Cleyton Crepaldi; Clop, Eduardo M; Couto, Verônica Muniz; Perillo, Maria Angelica; de Paula, Eneida

    2018-06-01

    The effect of the nonionic detergents Brij-98 and Brij-58 over human erythrocytes was studied through quantitative hemolysis and in Langmuir films. Hemolytic tests revealed that Brijs are stronger membrane solubilizers than Triton X-100 (TX-100), with effective detergent/lipid ratios of 0.18 and 0.37 for Brij-98 and Brij-58, respectively. Experiments with Langmuir films provided significant information on the kinetics and thermodynamics of detergent-membrane interaction. The adsorption (k a ) and desorption (k d ) rate constants of Brijs were lower than those of TX-100. In the case of k a , that is probably due to their larger hydrophilic head (with twice (20) the oxyethylene units of TX-100). As for the thermodynamic binding constant, the linear and longer hydrophobic acyl chains of Brijs favor their stabilization in-between the lipids, through London van der Waals forces. Consequently, K b,m values of Brij-98 (12,500 M -1 ) and Brij-58 (19,300 M -1 ) resulted higher than TX-100 (7500 M -1 ), in agreement with results from the hemolytic tests. Furthermore, Brij-58 binds with higher affinity than Brij-98 to bilayers and monolayers, despite its shorter (palmitic) hydrocarbon chain, showing that unsaturation restrains the detergent insertion into these environments. Our results provide significant information about the mechanism of interaction between Brijs and membranes, supporting their distinct solubilization effect. Copyright © 2018 Elsevier B.V. All rights reserved.

  12. Detergent Isolation Stabilizes and Activates the Shigella Type III Secretion System Translocator Protein IpaC.

    PubMed

    Bernard, Abram R; Duarte, Shari M; Kumar, Prashant; Dickenson, Nicholas E

    2016-07-01

    Shigella rely on a type III secretion system as the primary virulence factor for invasion and colonization of human hosts. Although there are an estimated 90 million Shigella infections, annually responsible for more than 100,000 deaths worldwide, challenges isolating and stabilizing many type III secretion system proteins have prevented a full understanding of the Shigella invasion mechanism and additionally slowed progress toward a much needed Shigella vaccine. Here, we show that the non-denaturing zwitterionic detergent N, N-dimethyldodecylamine N-oxide (LDAO) and non-ionic detergent n-octyl-oligo-oxyethylene efficiently isolated the hydrophobic Shigella translocator protein IpaC from the co-purified IpaC/IpgC chaperone-bound complex. Both detergents resulted in monomeric IpaC that exhibits strong membrane binding and lysis characteristics while the chaperone-bound complex does not, suggesting that the stabilizing detergents provide a means of following IpaC "activation" in vitro. Additionally, biophysical characterization found that LDAO provides significant thermal and temporal stability to IpaC, protecting it for several days at room temperature and brief exposure to temperatures reaching 90°C. In summary, this work identified and characterized conditions that provide stable, membrane active IpaC, providing insight into key interactions with membranes and laying a strong foundation for future vaccine formulation studies taking advantage of the native immunogenicity of IpaC and the stability provided by LDAO. Copyright © 2016 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.

  13. Quantitative proteomics reveals a dynamic association of proteins to detergent-resistant membranes upon elicitor signaling in tobacco.

    PubMed

    Stanislas, Thomas; Bouyssie, David; Rossignol, Michel; Vesa, Simona; Fromentin, Jérôme; Morel, Johanne; Pichereaux, Carole; Monsarrat, Bernard; Simon-Plas, Françoise

    2009-09-01

    A large body of evidence from the past decade supports the existence, in membrane from animal and yeast cells, of functional microdomains playing important roles in protein sorting, signal transduction, or infection by pathogens. In plants, as previously observed for animal microdomains, detergent-resistant fractions, enriched in sphingolipids and sterols, were isolated from plasma membrane. A characterization of their proteic content revealed their enrichment in proteins involved in signaling and response to biotic and abiotic stress and cell trafficking suggesting that these domains were likely to be involved in such physiological processes. In the present study, we used (14)N/(15)N metabolic labeling to compare, using a global quantitative proteomics approach, the content of tobacco detergent-resistant membranes extracted from cells treated or not with cryptogein, an elicitor of defense reaction. To analyze the data, we developed a software allowing an automatic quantification of the proteins identified. The results obtained indicate that, although the association to detergent-resistant membranes of most proteins remained unchanged upon cryptogein treatment, five proteins had their relative abundance modified. Four proteins related to cell trafficking (four dynamins) were less abundant in the detergent-resistant membrane fraction after cryptogein treatment, whereas one signaling protein (a 14-3-3 protein) was enriched. This analysis indicates that plant microdomains could, like their animal counterpart, play a role in the early signaling process underlying the setup of defense reaction. Furthermore proteins identified as differentially associated to tobacco detergent-resistant membranes after cryptogein challenge are involved in signaling and vesicular trafficking as already observed in similar studies performed in animal cells upon biological stimuli. This suggests that the ways by which the dynamic association of proteins to microdomains could participate in the regulation of the signaling process may be conserved between plant and animals.

  14. Quantitative Proteomics Reveals a Dynamic Association of Proteins to Detergent-resistant Membranes upon Elicitor Signaling in Tobacco*

    PubMed Central

    Stanislas, Thomas; Bouyssie, David; Rossignol, Michel; Vesa, Simona; Fromentin, Jérôme; Morel, Johanne; Pichereaux, Carole; Monsarrat, Bernard; Simon-Plas, Françoise

    2009-01-01

    A large body of evidence from the past decade supports the existence, in membrane from animal and yeast cells, of functional microdomains playing important roles in protein sorting, signal transduction, or infection by pathogens. In plants, as previously observed for animal microdomains, detergent-resistant fractions, enriched in sphingolipids and sterols, were isolated from plasma membrane. A characterization of their proteic content revealed their enrichment in proteins involved in signaling and response to biotic and abiotic stress and cell trafficking suggesting that these domains were likely to be involved in such physiological processes. In the present study, we used 14N/15N metabolic labeling to compare, using a global quantitative proteomics approach, the content of tobacco detergent-resistant membranes extracted from cells treated or not with cryptogein, an elicitor of defense reaction. To analyze the data, we developed a software allowing an automatic quantification of the proteins identified. The results obtained indicate that, although the association to detergent-resistant membranes of most proteins remained unchanged upon cryptogein treatment, five proteins had their relative abundance modified. Four proteins related to cell trafficking (four dynamins) were less abundant in the detergent-resistant membrane fraction after cryptogein treatment, whereas one signaling protein (a 14-3-3 protein) was enriched. This analysis indicates that plant microdomains could, like their animal counterpart, play a role in the early signaling process underlying the setup of defense reaction. Furthermore proteins identified as differentially associated to tobacco detergent-resistant membranes after cryptogein challenge are involved in signaling and vesicular trafficking as already observed in similar studies performed in animal cells upon biological stimuli. This suggests that the ways by which the dynamic association of proteins to microdomains could participate in the regulation of the signaling process may be conserved between plant and animals. PMID:19525550

  15. Study on OELs for enzyme-containing detergent in China.

    PubMed

    Zhang, X D; Liang, Y X; Lee, C S; Jin, T Y

    2004-01-01

    This study is aimed at setting occupational exposure levels for total detergent dust and enzymes in detergent industries. The study population consisted of 795 workers from four enzyme-containing detergent manufacturing plants (A1, A2, B1 and B2), and 156 control workers from an electronic assembly factory. Work environment monitoring was conducted using high volume of air sampler fro measuring the concentration of total dust (mg/m3), and analyzing the level of enzyme (ng/m3) by ELISA method. A standard questionnaires, pulmonary function test, and skin prick test are used to assess health effects. The levels of detergent total dust varied from 0.2 mg/m3 to 12.54 mg/m3. For enzyme levels, in A1, B1 and B2, the concentration ranged from non-detectable to 9.92 ng/m3 and in A2, the concentration was analyzed by enzyme activity methods and was expressed as Gu/m3 (1 Gu/m3 = 16 ng/m3). The concentration is between 0.16-31.36 ng/m3. Non-specific irritation rates in exposed workers were significantly higher than that in controls. Based on the data collected from A1, B1 and control plants, 95% benchmark dose lower bound were calculated as 1.17 mg/m3. The difference of pulmonary function between exposed workers and controls is not significant. The results of SPT showed that neither Savinase- nor Alcalase-induced sensitization was found in controls. The prevalence rates of sensitization for Savinase and Alcalase were ranged between 3.2% and 31% in all enzyme-containing detergent manufacturers investigated. No case of occupational asthma was observed. For total dust, 1 mg/m3 is suggested as permissible concentration-time weighted average (PC-TWA), and 2 mg/m3 as permissible concentration-short term exposure limit (PC-STEL). For the enzyme Subtilisins, 15 ng/m3 is suggested as PC-TWA, and 30 ng/m3 as PC-STEL.

  16. Effect of phospholipid, detergent and protein-protein interaction on stability and phosphoenzyme isomerization of soluble sarcoplasmic reticulum Ca-ATPase.

    PubMed

    Vilsen, B; Andersen, J P

    1987-12-30

    The purpose of the present study was to elucidate the separate roles of lipid, detergent and protein-protein interaction for stability and catalytic properties of sarcoplasmic reticulum Ca-ATPase solubilized in the non-ionic detergent octa(ethylene glycol) monododecyl ether (C12E8). The use of large-zone high-performance liquid chromatography permitted us to define the self-association state of Ca-ATPase peptide at various detergent, phospholipid and protein concentrations, and also during enzymatic turnover with ATP. Conditions were established for monomerization of Ca-ATPase in the presence of a high concentration of phospholipid relative to detergent. The lipid-saturated monomeric preparation was relatively resistant to inactivation in the absence of Ca2+, whereas delipidated enzyme in monomeric or in oligomeric form was prone to inactivation. Kinetics of phosphoenzyme turnover were examined in the presence and absence of Mg2+. Dephosphorylation rates were sensitive to Mg2+, irrespective of whether the peptide was present in soluble monomeric form or was membrane-bound. C12E8-solubilized monomer without added phospholipid was, however, characterized by a fast initial phase of dephosphorylation in the absence of Mg2+. This was not observed with monomer saturated with phospholipid or with monomer solubilized in myristoylglycerophosphocholine or deoxycholate. The mechanism underlying this difference was shown to be a C12E8-induced acceleration of conversion of ADP-sensitive phosphoenzyme (E1P) to ADP-insensitive phosphoenzyme (E2P). The phosphoenzyme isomerization rate was also found to be enhanced by low-affinity binding of ATP. This was demonstrated both in membrane-bound and in soluble monomeric Ca-ATPase. Our results indicate that a single peptide chain constitutes the target for modulation of phosphoenzyme turnover by Mg2+ and ATP, and that detergent effects, distinct from those arising from disruption of protein-protein contacts, are the major determinants of kinetic differences between C12E8-solubilized and membrane-bound enzyme preparations.

  17. Recyclability of PET/WPI/PE Multilayer Films by Removal of Whey Protein Isolate-Based Coatings with Enzymatic Detergents.

    PubMed

    Cinelli, Patrizia; Schmid, Markus; Bugnicourt, Elodie; Coltelli, Maria Beatrice; Lazzeri, Andrea

    2016-06-14

    Multilayer plastic films provide a range of properties, which cannot be obtained from monolayer films but, at present, their recyclability is an open issue and should be improved. Research to date has shown the possibility of using whey protein as a layer material with the property of acting as an excellent barrier against oxygen and moisture, replacing petrochemical non-recyclable materials. The innovative approach of the present research was to achieve the recyclability of the substrate films by separating them, with a simple process compatible with industrial procedures, in order to promote recycling processes leading to obtain high value products that will beneficially impact the packaging and food industries. Hence, polyethyleneterephthalate (PET)/polyethylene (PE) multi-layer film was prepared based on PET coated with a whey protein layer, and then the previous structure was laminated with PE. Whey proteins, constituting the coating, can be degraded by enzymes so that the coating films can be washed off from the plastic substrate layer. Enzyme types, dosage, time, and temperature optima, which are compatible with procedures adopted in industrial waste recycling, were determined for a highly-efficient process. The washing of samples based on PET/whey and PET/whey/PE were efficient when performed with enzymatic detergent containing protease enzymes, as an alternative to conventional detergents used in recycling facilities. Different types of enzymatic detergents tested presented positive results in removing the protein layer from the PET substrate and from the PET/whey/PE multilayer films at room temperature. These results attested to the possibility of organizing the pre-treatment of the whey-based multilayer film by washing with different available commercial enzymatic detergents in order to separate PET and PE, thus allowing a better recycling of the two different polymers. Mechanical properties of the plastic substrate, such as stress at yield, stress and elongation at break, evaluated by tensile testing on films before and after cleaning, were are not significantly affected by washing with enzymatic detergents.

  18. Vaginal microbicides: detecting toxicities in vivo that paradoxically increase pathogen transmission

    PubMed Central

    Cone, Richard A; Hoen, Timothy; Wong, XiXi; Abusuwwa, Raed; Anderson, Deborah J; Moench, Thomas R

    2006-01-01

    Background Microbicides must protect against STD pathogens without causing unacceptable toxic effects. Microbicides based on nonoxynol-9 (N9) and other detergents disrupt sperm, HSV and HIV membranes, and these agents are effective contraceptives. But paradoxically N9 fails to protect women against HIV and other STD pathogens, most likely because it causes toxic effects that increase susceptibility. The mouse HSV-2 vaginal transmission model reported here: (a) Directly tests for toxic effects that increase susceptibility to HSV-2, (b) Determines in vivo whether a microbicide can protect against HSV-2 transmission without causing toxicities that increase susceptibility, and (c) Identifies those toxic effects that best correlate with the increased HSV susceptibility. Methods Susceptibility was evaluated in progestin-treated mice by delivering a low-dose viral inoculum (0.1 ID50) at various times after delivering the candidate microbicide to detect whether the candidate increased the fraction of mice infected. Ten agents were tested – five detergents: nonionic (N9), cationic (benzalkonium chloride, BZK), anionic (sodium dodecylsulfate, SDS), the pair of detergents in C31G (C14AO and C16B); one surface active agent (chlorhexidine); two non-detergents (BufferGel®, and sulfonated polystyrene, SPS); and HEC placebo gel (hydroxyethylcellulose). Toxic effects were evaluated by histology, uptake of a 'dead cell' dye, colposcopy, enumeration of vaginal macrophages, and measurement of inflammatory cytokines. Results A single dose of N9 protected against HSV-2 for a few minutes but then rapidly increased susceptibility, which reached maximum at 12 hours. When applied at the minimal concentration needed for brief partial protection, all five detergents caused a subsequent increase in susceptibility at 12 hours of ~20–30-fold. Surprisingly, colposcopy failed to detect visible signs of the N9 toxic effect that increased susceptibility at 12 hours. Toxic effects that occurred contemporaneously with increased susceptibility were rapid exfoliation and re-growth of epithelial cell layers, entry of macrophages into the vaginal lumen, and release of one or more inflammatory cytokines (Il-1β, KC, MIP 1α, RANTES). The non-detergent microbicides and HEC placebo caused no significant increase in susceptibility or toxic effects. Conclusion This mouse HSV-2 model provides a sensitive method to detect microbicide-induced toxicities that increase susceptibility to infection. In this model, there was no concentration at which detergents provided protection without significantly increasing susceptibility. PMID:16740164

  19. The efficacy of different cleaning and disinfection procedures to reduce Salmonella and Enterobacteriaceae in the lairage environment of a pig abattoir.

    PubMed

    Walia, Kavita; Argüello, Hector; Lynch, Helen; Grant, Jim; Leonard, Finola C; Lawlor, Peadar G; Gardiner, Gillian E; Duffy, Geraldine

    2017-04-04

    This study investigated several cleaning and disinfection protocols for their ability to eliminate Salmonella and to reduce levels of Enterobacteriaceae, within the lairage pens of a commercial pig abattoir. Eight protocols were evaluated in each of 12 lairage pens at the end of the slaughtering day on 3 occasions (36 pens/protocol): (P1) high-pressure cold water wash (herein referred to as high-pressure wash); (P2) high-pressure wash followed by a quaternary ammonium compound (QAC)-based disinfectant without rinsing; (P3) high-pressure wash followed by a chlorocresol-based disinfectant without rinsing; (P4) high-pressure wash followed by a sodium hydroxide/sodium hypochlorite detergent with rinsing; (P5) P4 followed by P2; (P6) P4 followed by P3; (P7) P5 with drying for 24-48h; and (P8) P6 with drying for 24-48h. Two floor swabs and one wall swab were taken from each lairage pen before and after each protocol was applied, and examined for the presence of Salmonella and enumeration of Enterobacteriaceae. High-pressure washing alone (P1) did not reduce the prevalence of Salmonella in the lairage pens. When high-pressure washing, the probability of detecting Salmonella following application of the chlorocresol-based disinfectant (P3) was lower than with the QAC-based disinfectant, P2 (14.2% versus 34.0%, respectively; p<0.05). The probability of detecting Salmonella after the combined use of detergent and the chlorocresol-based disinfectant (P6) was also lower than application of detergent followed by the QAC-based disinfectant, P5 (2.2% versus 17.1%, respectively; p<0.05). Drying of pens (P7 and P8) greatly reduced the probability of detecting Salmonella. Only 3.8% of swabs were Salmonella-positive 48h after cleaning with detergent and the QAC-based disinfectant (P7); while an eradication of Salmonella was achieved 24h after cleaning with detergent and the chlorocresol-based disinfectant, P8. A reduction in Enterobacteriaceae counts to below the limit of detection (LOD; 10CFU/cm 2 ) was achieved following cleaning with detergent and disinfection with the chlorocresol-based disinfectant, regardless of drying (p<0.05), whereas, applying detergent and the QAC-based disinfectant (P7) did not reduce Enterobacteriaceae counts to below the LOD. Therefore ensuring that lairage pens are allowed to dry after intensive cleaning with detergent and a chlorocresol-based disinfectant is recommended as the most effective hygiene routine to eliminate Salmonella and reduce Enterobacteriaceae counts. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Concentrations and apparent digestibility of lignin and carbohydrate fractions in cell walls of whole-crop cereal silages

    USDA-ARS?s Scientific Manuscript database

    Whole-crop cereal silage (WCCS) of oats generally has lower fiber digestibility than WCCS of barley. When investigated more closely, the difference seems mainly to be in the digestibility of the hemicellulosic fraction (HC), where HC is calculated as neutral detergent fibre (NDF) – acid detergent fi...

  1. Quantifying Ruminal Digestion of Organic Matter and Neutral Detergent Fiber Using Omasal Sampling in Cattle--A Meta-Analysis

    USDA-ARS?s Scientific Manuscript database

    A data set from 32 studies (122 diets) was used to evaluate the accuracy and precision of the omasal sampling technique by investigating the relationships between ruminal and total digestion of neutral detergent fiber (NDF), between intake and apparent and true ruminal digestion of organic matter (O...

  2. Seasonal changes in chemical composition and nutritive value of native forages in a spruce-hemlock forest, southeastern Alaska.

    Treesearch

    Thomas A. Hanley; Jay D. McKendrick

    1983-01-01

    Twenty-two forages from Admiralty Island, southeastern Alaska, were monitored bimonthly for one year to assess seasonal changes in their chemical composition: neutral detergent fiber, acid detergent fiber, cellulose, lignin/cutin, invitro dry-matter digestibility, total nitrogen, phosphorus, potassium, calcium, magnesium, sodium, copper, manganese, iron, and zinc....

  3. How Do Detergents Work? A Qualitative Assay to Measure Amylase Activity

    ERIC Educational Resources Information Center

    Novo, M. Teresa; Casanoves, Marina; Garcia-Vallvé, Santi; Pujadas, Gerard; Mulero, Miquel; Valls, Cristina

    2016-01-01

    We present a practical activity focusing on two main goals: to give learners the opportunity to experience how the scientific method works and to increase their knowledge about enzymes in everyday situations. The exercise consists of determining the amylase activity of commercial detergents. The methodology is based on a qualitative assay using a…

  4. Laboratory Inquiry for Determining the Chemical Composition of a Component in a Daily Use Detergent: Sodium Sesquicarbonate

    ERIC Educational Resources Information Center

    Koga, Nobuyoshi; Kimura, Tomoyasu; Shigedomi, Kana

    2011-01-01

    An inquiry-based laboratory activity to determine the chemical composition of a component in alkaline detergents, sodium sesquicarbonate (SSC), is proposed. On the basis of introductory demonstrations by the instructor on the chemical properties and reactions of SSC, students propose the hypothetical composition of SSC and possible quantitative…

  5. Influence of ponderosa pine overstory on forage quality in the Black Hills, South Dakota

    Treesearch

    Kieth E. Severson; Daniel W. Uresk

    1988-01-01

    Forage quality was assessed in pole and sapling ponderosa pine (Pinus ponderosa) stands growing at five stocking levels - 0, 5. 14, 23, and unthinned (which approximated 40 m2/ha basal area)-in the Black Hills of South Dakota. Crude protein, acid detergent fiber, acid detergent lignin, ash, calcium, and phosphorus were...

  6. High-performance liquid chromatography separation and intact mass analysis of detergent-solubilized integral membrane proteins

    PubMed Central

    Berridge, Georgina; Chalk, Rod; D’Avanzo, Nazzareno; Dong, Liang; Doyle, Declan; Kim, Jung-In; Xia, Xiaobing; Burgess-Brown, Nicola; deRiso, Antonio; Carpenter, Elisabeth Paula; Gileadi, Opher

    2011-01-01

    We have developed a method for intact mass analysis of detergent-solubilized and purified integral membrane proteins using liquid chromatography–mass spectrometry (LC–MS) with methanol as the organic mobile phase. Membrane proteins and detergents are separated chromatographically during the isocratic stage of the gradient profile from a 150-mm C3 reversed-phase column. The mass accuracy is comparable to standard methods employed for soluble proteins; the sensitivity is 10-fold lower, requiring 0.2–5 μg of protein. The method is also compatible with our standard LC–MS method used for intact mass analysis of soluble proteins and may therefore be applied on a multiuser instrument or in a high-throughput environment. PMID:21093405

  7. Intermolecular interactions at early stage of protein/detergent particle association induced by salt/polyethylene glycol mixtures.

    PubMed

    Odahara, Takayuki; Odahara, Koji

    2016-04-01

    Mixtures of neutral salts and polyethylene glycol are used for various purposes in biological studies. Although the effects of each component of the mixtures are theoretically well investigated, comprehension of their integrated effects remains insufficient. In this work, their roles and effects as a precipitant were clarified by studying dependence of precipitation curves on salt concentration for integral membrane protein/detergent particles of different physicochemical properties. The dependence of precipitation curves was reasonably related to intermolecular interactions among relevant molecules such as protein, detergent and polyethylene glycol by considering their physicochemical properties. The obtained relationships are useful as basic information to learn the early stage of biological macromolecular associations. Copyright © 2015 Elsevier Inc. All rights reserved.

  8. Detergent-dispersant additives based on high-molecular-weight alkylphenols

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kulieva, K.N.; Namazova, I.I.; Ismailova, N.D.

    1988-09-01

    This article describes the synthesis and investigation of Mannich bases produced for alkylphenols, obtained in turn from ethylene oligomers. These oligomers are the still bottoms from distillation products of high-temperature oligomerization of ethylene in the presence of triethylaluminum. Two narrow cuts obtained from the distillation of oligomer fraction were used to study the influence of ethylene oligomer molecular weight on the properties of the additives. The additives were blended in DS-11 oil to evaluate their detergency-dispersancy and other properties. Comparison blends were made with succinimide additives based on the same ethylene oligomers. The Mannich bases give improvements in the oxidationmore » resistance, anticorrosion properties, and detergency-dispersancy of the DS-11 diesel oil.« less

  9. Improving the apo-state detergent stability of NTS1 with CHESS for pharmacological and structural studies.

    PubMed

    Scott, Daniel J; Kummer, Lutz; Egloff, Pascal; Bathgate, Ross A D; Plückthun, Andreas

    2014-11-01

    The largest single class of drug targets is the G protein-coupled receptor (GPCR) family. Modern high-throughput methods for drug discovery require working with pure protein, but this has been a challenge for GPCRs, and thus the success of screening campaigns targeting soluble, catalytic protein domains has not yet been realized for GPCRs. Therefore, most GPCR drug screening has been cell-based, whereas the strategy of choice for drug discovery against soluble proteins is HTS using purified proteins coupled to structure-based drug design. While recent developments are increasing the chances of obtaining GPCR crystal structures, the feasibility of screening directly against purified GPCRs in the unbound state (apo-state) remains low. GPCRs exhibit low stability in detergent micelles, especially in the apo-state, over the time periods required for performing large screens. Recent methods for generating detergent-stable GPCRs, however, offer the potential for researchers to manipulate GPCRs almost like soluble enzymes, opening up new avenues for drug discovery. Here we apply cellular high-throughput encapsulation, solubilization and screening (CHESS) to the neurotensin receptor 1 (NTS1) to generate a variant that is stable in the apo-state when solubilized in detergents. This high stability facilitated the crystal structure determination of this receptor and also allowed us to probe the pharmacology of detergent-solubilized, apo-state NTS1 using robotic ligand binding assays. NTS1 is a target for the development of novel antipsychotics, and thus CHESS-stabilized receptors represent exciting tools for drug discovery. Copyright © 2014 Elsevier B.V. All rights reserved.

  10. Sewage plume in a sand and gravel aquifer, Cape Cod, Massachusetts

    USGS Publications Warehouse

    LeBlanc, D.R.

    1982-01-01

    Secondarily treated domestic sewage has been disposed of to a sand and gravel aquifer by infiltration through sand beds at Otis Air Force Base, Massachusetts, since 1936. The disposal has formed a plume of contaminated ground water that is more than 11 ,000 feet long, is 2,500 to 3,500 feet wide and 75 feet thick, and is overlain by 20 to 50 feet of uncontaminated ground water derived from precipitation. The distributions of specific conductance, temperature, boron chloride, sodium, phosphorus, nitrogen, ammonia, nitrate, dissolved oxygen, and detergents are used to delineate the plume. The center of the plume contains up to 2.6 milligrams per liter detergents as MBAS (methylene blue active substances), 0.4 milligram per liter boron, 20 milligrams per liter ammonia-nitrogen, and specific conductance as high as 405 micromhos per centimeter. Corresponding levels in uncontaminated ground water are less than 0.1 milligram per liter detergents, less than 0.1 ammonia-nitrogen, less than 0.05 milligram per liter boron, and less than 80 micromhos per centimeter specific conductance. Chloride, sodium, and boron concentrations seem to be affected only by hydrodynamic dispersion. Phosphorus movement is greatly retarded by sorption. Detergent concentrations exceed 0.5 milligram per liter from 3 ,000 to 10,000 feet from the sand beds and reflect the use of nonbiodegradable detergents from 1946 through 1964. The center of the plume as far as 5,000 feet from the sand beds contains nitrogen as ammonia, no nitrate, and no dissolved oxygen. Ammonia is oxidized to nitrate gradually with distance from the center of the plume. (USGS)

  11. PH-dependence of detergent-induced hemolysis and vesiculation of erythrocytes.

    PubMed

    Chernitsky, E A; Rozin, V V; Senkovich, O A

    2001-01-01

    The influence of pH of the medium on the parameters of detergent-induced fast hemolysis and vesiculation of human erythrocytes was studied. In the range of pH 6.3-7.2 neither the extent nor the rate of the vesiculation induced by 25 microM sodium dodecyl sulfate (SDS) changed. However, a decrease of pH from 8.0 to 5.8 strongly modified both the extent and the rate of the hemolysis induced by SDS. Within the range of pH 8.0-6.4, the effect can be ascribed to the increase of the positive charge of the membrane. This could lead to the accumulation of the membrane-bound anion detergent and, hence, to the change of the hemolysis parameters. Non-charged detergent Triton X-100 did not display any pH-dependence. At pH between 6.4 and 5.8 the extent and rate of hemolysis changed in a complicated manner. The kinetic curves of hemolysis could be approximated by a single exponential within the pH range between 8.0 and 7.2. Upon further reduction of pH, a second exponential component, with a larger time constant, appeared in the kinetic curves. At 5.8 < pH < 7.2, the contribution of the "fast" hemolysis dropped virtually to zero, with pK about 6.0. This points to a structural transition of the membrane, possibly involving histidine. We suggest that the parameters of the detergent-induced hemolysis are sensitive to the changes of the charge and structural state of erythrocyte membrane.

  12. Tandem neopentyl glycol maltosides (TNMs) for membrane protein stabilisation†

    PubMed Central

    Bae, Hyoung Eun; Mortensen, Jonas S.; Ribeiro, Orquidea; Du, Yang; Ehsan, Muhammad; Kobilka, Brian K.; Loland, Claus J.; Byrne, Bernadette

    2017-01-01

    A novel class of detergents, designated tandem neopentyl glycol maltosides (TNMs), were evaluated with four target membrane proteins. The best detergent varied depending on the target, but TNM-C12L and TNM-C11S were notable for their ability to confer increased membrane protein stability compared to DDM. These agents have potential for use in membrane protein research. PMID:27711401

  13. Tandem neopentyl glycol maltosides (TNMs) for membrane protein stabilisation.

    PubMed

    Bae, Hyoung Eun; Mortensen, Jonas S; Ribeiro, Orquidea; Du, Yang; Ehsan, Muhammad; Kobilka, Brian K; Loland, Claus J; Byrne, Bernadette; Chae, Pil Seok

    2016-10-04

    A novel class of detergents, designated tandem neopentyl glycol maltosides (TNMs), were evaluated with four target membrane proteins. The best detergent varied depending on the target, but TNM-C12L and TNM-C11S were notable for their ability to confer increased membrane protein stability compared to DDM. These agents have potential for use in membrane protein research.

  14. Laundry detergent and possible nonaccidental injury.

    PubMed

    Howieson, Alan J; Harley, Oliver J H; Tiernan, Eunan P

    2007-06-01

    Nonaccidental injury is always a concern when children present with unusual injuries. The case of a child who presented with a partial thickness burn secondary to prolonged contact with a liquid biological laundry detergent is described. Initially there was some doubt as to whether the agent in question could cause this injury but a small experiment on a volunteer confirmed it was possible.

  15. Detergent-Based Isolation of Yeast Membrane Rafts: An Inquiry-Based Laboratory Series for the Undergraduate Cell Biology or Biochemistry Lab

    ERIC Educational Resources Information Center

    Willhite, D. Grant; Wright, Stephen E.

    2009-01-01

    Lipid rafts have been implicated in numerous cellular processes including cell signaling, endocytosis, and even viral infection. Isolation of these lipid rafts often involves detergent treatment of the membrane to dissolve nonraft components followed by separation of raft regions in a density gradient. We present here an inquiry-based lab series…

  16. Arsenic in detergents: Possible danger and pollution hazard

    USGS Publications Warehouse

    Angino, E.E.; Magnuson, L.M.; Waugh, T.C.; Galle, O.K.; Bredfeldt, J.

    1970-01-01

    Arsenic at a concentration of 10 to 70 parts per million has been detected in several common presoaks and household detergents. Arsenic values of 2 to 8 parts per billion have been measured in the Kansas River. These concentrations are close to the amount (10 parts per billion) recommended by the United States Public Health Service as a drinking-water standard.

  17. Comparison of methods for extracting DNA from formalin-fixed paraffin sections for nonisotopic PCR.

    PubMed

    Frank, T S; Svoboda-Newman, S M; Hsi, E D

    1996-09-01

    DNA was extracted from unstained 5-microns sections of neutral buffered 10% formalin-fixed paraffin-embedded tissue by proteinase K digestion without detergents followed by boiling, proteinase K digestion with ionic detergents with and without phenol chloroform extraction and ethanol precipitation, sonication with proteinase K followed by boiling, or boiling alone. Serial 1:10 dilutions of the extracted DNA were subject to polymerase chain reaction (PCR) amplification of a 255-bp portion of the p53 gene. Digestion with proteinase K without ionic detergents followed by boiling (without phenol chloroform extraction) gave the best yield, enabling visualization of ethidium bromide-stained PCR product from a DNA dilution corresponding to 0.1 mm2 of tissue containing of the order of 10(3) nuclear profiles. Proteinase K digestion with detergents followed by phenol-chloroform extraction was no more effective than simple boiling. Although the success of PCR from preserved tissue will vary with the fixative and size of the amplified fragment, DNA extracted with this optimized method can be used for identification of viruses, loss of heterozygosity, and immunoglobulin gene rearrangements in paraffin-embedded tissue without radioisotopes.

  18. Supersaturation-Limited and Unlimited Phase Spaces Compete to Produce Maximal Amyloid Fibrillation near the Critical Micelle Concentration of Sodium Dodecyl Sulfate.

    PubMed

    So, Masatomo; Ishii, Akira; Hata, Yasuko; Yagi, Hisashi; Naiki, Hironobu; Goto, Yuji

    2015-09-15

    Although various natural and synthetic compounds have been shown to accelerate or inhibit the formation of amyloid fibrils, the mechanisms by which they achieve these adverse effects in a concentration-dependent manner currently remain unclear. Sodium dodecyl sulfate (SDS), one of the compounds that has adverse effects on fibrillation, is the most intensively studied. Here we examined the effects of a series of detergents including SDS on the amyloid fibrillation of β2-microglobulin at pH 7.0, a protein responsible for dialysis-related amyloidosis. In all the detergents examined (i.e., SDS, sodium decyl sulfate, sodium octyl sulfate, and sodium deoxycholate), amyloid fibrillation was accelerated and inhibited at concentrations near the critical micelle concentration (CMC) and higher than CMC, respectively. The most stable conformation changed from monomers with a β-structure to amyloid fibrils with a β-structure and then to α-helical complexes with micelles with an increase in detergent concentrations. These results suggest that competition between supersaturation-limited fibrillation and unlimited mixed micelle formation between proteins and micelles underlies the detergent concentration-dependent complexity of amyloid fibrillation.

  19. Hand hygiene and skin health.

    PubMed

    Kownatzki, E

    2003-12-01

    The high rate of hand problems associated with the hand hygiene of medical professions is due to a combination of damaging factors: (1) the removal of barrier lipids by detergent cleaning and alcohol antisepsis followed by a loss of moisturizers and stratum corneum water and (2) the overhydration of the stratum corneum by sweat trapped within gloves. Together the facilitate the invasion of irritants and allergens which elicit inflammatory responses in the dermis. Among the lipids and water-soluble substances removed are natural antibacterials. Their loss leads to increased growth of transient and pathogenic micro-organisms which jeapordizes the very intention of skin hygiene. The kinetics of damage and its repair, and epidemiological evidence suggest that modern synthetic detergents as used in foaming liquid cleansers are the major offender. Conversely, the replacement of detergents with non-detergent emulsion cleansers has been shown to be effective in reducing the prevalence of hand problems among hospital staff. Presently recommended hand antisepsis reduces the risks to patients, but puts the burden on the health care provider. Rather than fighting micro-organisms at the expense of the skin's health, the skin and its own defences should be considered a collaborator in combating infectious diseases.

  20. Differential solubilization of inner plasma membrane leaflet components by Lubrol WX and Triton X-100.

    PubMed

    Delaunay, Jean-Louis; Breton, Michelyne; Trugnan, Germain; Maurice, Michèle

    2008-01-01

    A commonly-used method for analysing raft membrane domains is based on their resistance to extraction by non-ionic detergents at 4 degrees C. However, the selectivity of different detergents in defining raft membrane domains has been questioned. We have compared the lipid composition of detergent-resistant membranes (DRMs) obtained after Triton X-100 or Lubrol WX extraction in MDCK cells in order to understand the differential effect of these detergents on membranes and their selectivity in solubilizing or not proteins. Both Lubrol and Triton DRMs were enriched with cholesterol over the lysate, thus exhibiting characteristics consistent with the properties of membrane rafts. However, the two DRM fractions differed considerably in the ratio between lipids of the inner and outer membrane leaflets. Lubrol DRMs were especially enriched with phosphatidylethanolamine, including polyunsaturated species with long fatty acyl chains. Lubrol and Triton DRMs also differed in the amount of raft transmembrane proteins and raft proteins anchored to the cytoplasmic leaflet. Our results suggest that the inner side of rafts is enriched with phosphatidylethanolamine and cholesterol, and is more solubilized by Triton X-100 than by Lubrol WX.

  1. Occupational asthma and allergy in the detergent industry: new developments.

    PubMed

    Sarlo, Katherine; Kirchner, Donald B

    2002-04-01

    This review highlights the latest developments in the control of enzyme-induced occupational asthma and allergy (rhinitis and conjunctivitis) in the detergent industry. The industry has developed guidelines for the safe handling of enzymes in order to reduce the risk of occupational allergy and asthma. Those manufacturing facilities that follow all of the guidelines enjoy very low or no cases of asthma and allergy among workers exposed to enzymes. The key to the success of the management of enzyme-induced allergy and asthma is prospective surveillance for the development of enzyme-specific IgE antibody before the onset of allergic symptoms. This allows for continuing interventions to reduce exposures, so as to minimize or eliminate those associated with symptoms. Workers with IgE to enzymes can still continue to work in the industry symptom-free for their entire career. This indicates that exposures needed to induce sensitization are different and probably lower than exposures needed to elicit enzyme allergic symptoms. The experience of the detergent enzyme industry in controlling occupational allergens can be applied to other industries. The detergent enzyme story can be viewed as a model for the control of type 1 protein allergens in the workplace.

  2. Laundry detergent "pod" ingestions: a case series and discussion of recent literature.

    PubMed

    Beuhler, Michael C; Gala, Payal K; Wolfe, Heather A; Meaney, Peter A; Henretig, Fred M

    2013-06-01

    The objectives of this study were to present and explore the clinical presentation of the increasingly common pediatric exposure to the widely available single-use laundry packets or "laundry pods." This is a case report of 4 pediatric patients with significant toxicity due to laundry pod detergent exposure and a review of the available literature including abstract-only publications. An unexpectedly severe clinical pattern was noted; 3 of the 4 children required intubation for management, airway injury was noted in 1 of them, and 2 of them had hospital courses of at least 1 week. The literature suggests that laundry pod exposures are associated with increased morbidity compared to traditional laundry detergent exposures. To date, no specific contaminant or component has been identified as being responsible for the injury, although some evidence points to the surfactant component. A different approach to the triage and management of pediatric exposures to laundry detergent pod ingestions is required compared with nonpod ingestions. Although the exact cause is not known, practitioners should be vigilant for rapid onset of neurological impairment and inability to protect the airway in addition to its caustic effects.

  3. Cholesterol depletion modulates detergent resistant fraction of human serotonin(1A) receptors.

    PubMed

    Sahu, Santosh Kumar; Saxena, Roopali; Chattopadhyay, Amitabha

    2012-11-01

    Insolubility of membrane components in non-ionic detergents such as Triton X-100 at low temperature is a widely used biochemical criterion to identify, isolate and characterize membrane domains. In this work, we monitored the detergent insolubility of the serotonin(1A) receptor in CHO cell membranes and its modulation by membrane cholesterol. The serotonin(1A) receptor is an important member of the G-protein coupled receptor family. It is implicated in the generation and modulation of various cognitive, behavioral and developmental functions and serves as a drug target. Our results show that a significant fraction (∼28%) of the serotonin(1A) receptor resides in detergent-resistant membranes (DRMs). Interestingly, the fraction of the serotonin(1A) receptor in DRMs exhibits a reduction upon membrane cholesterol depletion. In addition, we show that contents of DRM markers such as flotillin-1, caveolin-1 and GM₁ are altered in DRMs upon cholesterol depletion. These results assume significance since the function of the serotonin(1A) receptor has previously been shown to be affected by membrane lipids, specifically cholesterol. Our results are relevant in the context of membrane organization of the serotonin(1A) receptor in particular, and G-protein coupled receptors in general.

  4. Expression, stabilization and purification of membrane proteins via diverse protein synthesis systems and detergents involving cell-free associated with self-assembly peptide surfactants.

    PubMed

    Zheng, Xuan; Dong, Shuangshuang; Zheng, Jie; Li, Duanhua; Li, Feng; Luo, Zhongli

    2014-01-01

    G-protein coupled receptors (GPCRs) are involved in regulating most of physiological actions and metabolism in the bodies, which have become most frequently addressed therapeutic targets for various disorders and diseases. Purified GPCR-based drug discoveries have become routine that approaches to structural study, novel biophysical and biochemical function analyses. However, several bottlenecks that GPCR-directed drugs need to conquer the problems including overexpression, solubilization, and purification as well as stabilization. The breakthroughs are to obtain efficient protein yield and stabilize their functional conformation which are both urgently requiring of effective protein synthesis system methods and optimal surfactants. Cell-free protein synthesis system is superior to the high yields and post-translation modifications, and early signs of self-assembly peptide detergents also emerged to superiority in purification of membrane proteins. We herein focus several predominant protein synthesis systems and surfactants involving the novel peptide detergents, and uncover the advantages of cell-free protein synthesis system with self-assembling peptide detergents in purification of functional GPCRs. This review is useful to further study in membrane proteins as well as the new drug exploration. Copyright © 2014 Elsevier Inc. All rights reserved.

  5. Food selection in relation to nutritional chemistry of Cao Vit gibbons in Jingxi, China.

    PubMed

    Ma, Changyong; Liao, Jiancun; Fan, Pengfei

    2017-01-01

    The Cao Vit gibbon (Nomascus nasutus) has only one population with about 110 individuals living in a degraded karst forest along the China-Vietnam border. Investigation of food choice in relation to chemical nutrition will offer important insights into its conservation. We studied the food choice of two groups of Cao Vit gibbons using instantaneous scan sampling in Bangliang National Nature Reserve, Guangxi, China, over 4 years, and analyzed the chemical components (total nitrogen, TN; water-soluble sugar, WSS; crude fat, CF; neutral detergent fiber, NDF; acid detergent fiber, ADF; acid detergent lignin, ADL; condensed tannin, CT; and ash) of 48 food plant parts and 22 non-food plant parts. Fruits and figs that are rich in sugar are important food resources for gibbons. For other food types, flowers are a good source of total nitrogen and carbohydrates, and leaves and buds provide sources of protein and minerals. Cao Vit gibbons selected fruits that contain less total nitrogen, less acid detergent fiber and more water-soluble sugar than non-food fruits. Several food species that were heavily consumed by Cao Vit gibbons are suggested as potential tree species for ongoing habitat restoration.

  6. Erythrocyte hemolysis by detergents.

    PubMed

    Chernitsky, E A; Senkovich, O A

    1997-01-01

    The numbers of Triton X-100 and sodium dodecyl sulfate molecules required to form respective pores were estimated from the relationship between the detergent concentrations and the rates of fast and slow hemolysis components. It has been found that the slow hemolysis component evoked by Triton X-100 is related to the existence of two different pores. It is shown that the fast hemolysis component induced by sodium dodecyl sulfate is associated with the modification of phosphatidylcholine which determines the break in the Arrhenius plots of the hemolysis rate within the range of 20 degrees C. The shape of hemolysis kinetic curves and the dependence of hemolytic parameters on the detergent concentration and temperature are discussed based on the concept of hemolysis caused by the formation of pores in various membrane lipid regions and by releasing vesicles from erythrocytes.

  7. Metabolism of Some Anionic Tallow-based Detergents by Sewage Microorganisms1

    PubMed Central

    Cordon, Theone C.; Maurer, Elmer W.; Nuñez-Ponzoa, M. V.; Stirton, A. J.

    1968-01-01

    A method in which the test detergent was the sole source of carbon was used to study the metabolism of several tallow-based detergents. These were tallow alcohol sulfates, long-chain ether alcohol sulfates, and esters of α-sulfo fatty acids. Sodium p-(1-methylundecyl)benzenesulfonate (LAS) was used as a reference material. The alcohol sulfates were the most rapidly and completely metabolized (96 to 99%), and one ether alcohol sulfate was 94% degraded. The other compounds were metabolized to the extent of 61 to 87%; LAS was 80% degraded. Except for the alcohol sulfates, loss of methylene blue activity (MBAS) occurred long before the chemical oxygen demand (COD) values had reached a minimum; with the alcohol sulfates, MBAS and COD decreased simultaneously. PMID:5636472

  8. New Analytical Method for the Determination of Detergent Concentration in Water by Fabric Dyeing

    ERIC Educational Resources Information Center

    Seng, Set; Kita, Masakazu; Sugihara, Reiko

    2007-01-01

    The use of harmful organic solvents in classrooms has become a critical issue of concern in the field of chemistry education. This article describes a classroom activity at a high school in which an acrylic fabric was used as the extraction medium in the analysis of the detergent concentration in water instead of organic solvents. Dyes were used…

  9. Developing a maximum energy efficiency improvement target for SIC 28: chemicals and allied products. Volume 3. Draft target and support document. Appendices. Part 2. [Soaps, cosmetics, detergents, and perfumes

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    1976-07-01

    Part 2 of this appendix contains the detailed supporting documentation and rationale for the energy efficiency improvement goals for each of the component industries in Standard Industrial Classification (SIC) 284 which includes soap, detergents and cleaning preparations, and cosmetics, perfumes and other toilet preparations.

  10. Recyclability of PET/WPI/PE Multilayer Films by Removal of Whey Protein Isolate-Based Coatings with Enzymatic Detergents

    PubMed Central

    Cinelli, Patrizia; Schmid, Markus; Bugnicourt, Elodie; Coltelli, Maria Beatrice; Lazzeri, Andrea

    2016-01-01

    Multilayer plastic films provide a range of properties, which cannot be obtained from monolayer films but, at present, their recyclability is an open issue and should be improved. Research to date has shown the possibility of using whey protein as a layer material with the property of acting as an excellent barrier against oxygen and moisture, replacing petrochemical non-recyclable materials. The innovative approach of the present research was to achieve the recyclability of the substrate films by separating them, with a simple process compatible with industrial procedures, in order to promote recycling processes leading to obtain high value products that will beneficially impact the packaging and food industries. Hence, polyethyleneterephthalate (PET)/polyethylene (PE) multi-layer film was prepared based on PET coated with a whey protein layer, and then the previous structure was laminated with PE. Whey proteins, constituting the coating, can be degraded by enzymes so that the coating films can be washed off from the plastic substrate layer. Enzyme types, dosage, time, and temperature optima, which are compatible with procedures adopted in industrial waste recycling, were determined for a highly-efficient process. The washing of samples based on PET/whey and PET/whey/PE were efficient when performed with enzymatic detergent containing protease enzymes, as an alternative to conventional detergents used in recycling facilities. Different types of enzymatic detergents tested presented positive results in removing the protein layer from the PET substrate and from the PET/whey/PE multilayer films at room temperature. These results attested to the possibility of organizing the pre-treatment of the whey-based multilayer film by washing with different available commercial enzymatic detergents in order to separate PET and PE, thus allowing a better recycling of the two different polymers. Mechanical properties of the plastic substrate, such as stress at yield, stress and elongation at break, evaluated by tensile testing on films before and after cleaning, were are not significantly affected by washing with enzymatic detergents. PMID:28773592

  11. The Content of Dietary Fibre and Polyphenols in Morphological Parts of Buckwheat (Fagopyrum tataricum).

    PubMed

    Dziedzic, Krzysztof; Górecka, Danuta; Szwengiel, Artur; Sulewska, Hanna; Kreft, Ivan; Gujska, Elżbieta; Walkowiak, Jarosław

    2018-03-01

    In this report, we presented the profile of polyphenolic substances in flowers, leaves, stalk and roots of Fagopyrum tataricum estimated by using RP-UHPLC-ESI-MS equipment (reversed-phase ultra-high-performance liquid chromatography electrospray ionisation mass spectrometry). The neutral detergent fibre, acid detergent fibre, acid detergent lignin, cellulose and hemicellulose were also determined. Flowers, leaves, stalk and roots showed varying levels of dietary fibre and polyphenols. The highest content of neutral and acid detergent fibre were found in the roots (63.92 and 45.45% d.m., respectively) while the most rich in phenolic compounds were flowers (4.8 mg/1 g d.m.). Root and stalk contained the highest level of cellulose, 38.70 and 25.57% d.m., respectively. Among the investigated polyphenolic substances such as: 2,6-dihydroxybenzoic acid, 3,4-dihydroxybenzoic acid, 3,5-dihydroxybenzoic acid, 4-hydrobenzoic acid, caffeic acid, catechin, chlorogenic acid, fagopyrin, ferulic acid, myricetin, gallic acid, isovanilic acid, isovitexin, kaempferol, luteolin, p-coumaric acid, procyanidin B2, quercetin, quercetin 3-D galactoside, rutin, syringic acid and vitexin, we observed that the contents of rutin and chlorogenic acid were the highest. We found some correlation between dietary fibre fractions and individual phenolic substances. The levels of acid detergent fibre (ADF), cellulose and hemicellulose were negatively correlated with isovitexin, kaempferol, vitexin, fagopyrin, caffeic acid and procyanidin B2 content. In this investigation, two solvents (water and methanol) were estimated regarding their extraction efficiency of phenolic compounds. Taking these results into consideration, we recommend using methanol as the extractor to isolate chlorogenic acid, fagopyrin, kaempferol, procyanidin B2, quercetin, quercetin 3-D-galactoside, rutin, vitexin, and water for other investigated polyphenolic substances obtained from Fagopyrum tataricum.

  12. Expression and solubilization of insect cell-based rabies virus glycoprotein and assessment of its immunogenicity and protective efficacy in mice.

    PubMed

    Ramya, R; Mohana Subramanian, B; Sivakumar, V; Senthilkumar, R L; Sambasiva Rao, K R S; Srinivasan, V A

    2011-10-01

    Rabies is a fatal zoonotic disease of serious public health and economic significance worldwide. The rabies virus glycoprotein (RVG) has been the major target for subunit vaccine development, since it harbors domains responsible for induction of virus-neutralizing antibodies, infectivity, and neurovirulence. The glycoprotein (G) was cloned using the baculovirus expression vector system (BEVS) and expressed in Spodoptera frugiperda (Sf-9) cells. In order to obtain a soluble form of G suitable for experimentation in mice, 18 different combinations of buffers and detergents were evaluated for their ability to solubilize the insect cell membrane-associated G. The combination that involved 3-[(3-cholamidopropyl)-dimethylammonio]-1-propanesulfonate (CHAPS) detergent in lysis buffer 1, formulated with Tris, NaCl, 10% dimethyl sulfoxide (DMSO), and EDTA, gave the highest yield of soluble G, as evidenced by the experimental data. Subsequently, several other parameters, such as the concentration of CHAPS and the duration and temperature of the treatment for the effective solubilization of G, were optimized. The CHAPS detergent, buffered at a concentration of 0.4% to 0.7% (wt/vol) at room temperature (23 to 25°C) for 30 min to 1 h using buffer 1, containing 10% DMSO, resulted in consistently high yields. The G solubilized using CHAPS detergent was found to be immunogenic when tested in mice, as evidenced by high virus-neutralizing antibody titers in sera and 100% protection upon virulent intracerebral challenge with the challenge virus standard (CVS) strain of rabies virus. The results of the mice study indicated that G solubilized with CHAPS detergent retained the immunologically relevant domains in the native conformation, thereby paving the way for producing a cell-free and efficacious subunit vaccine.

  13. ABC-transporters are localized in caveolin-1-positive and reggie-1-negative and reggie-2-negative microdomains of the canalicular membrane in rat hepatocytes.

    PubMed

    Ismair, Manfred G; Häusler, Stephanie; Stuermer, Claudia A; Guyot, Christelle; Meier, Peter J; Roth, Jürgen; Stieger, Bruno

    2009-05-01

    The canalicular plasma membrane is constantly exposed to bile acids acting as detergents. Bile acids are essential to mediate release of biliary lipids from the canalicular membrane. Membrane microdomains (previously called lipid rafts) are biochemically defined by their resistance to detergent solubilization at cold temperature. We aimed to investigate the canalicular plasma membrane for the presence of microdomains, which could protect this membrane against the detergent action of bile acids. Highly purified rat liver canalicular plasma membrane vesicles were extracted with 1% Triton X-100 or 1% Lubrol WX at 4 degrees C and subjected to flotation through sucrose step gradients. Both detergents yielded detergent-resistant membranes containing the microdomain markers alkaline phosphatase and sphingomyelin. However, cholesterol was resistant to Lubrol WX solubilization, whereas it was only marginally resistant to solubilization by Triton X-100. The microdomain marker caveolin-1 was localized to the canalicular plasma membrane domain and was resistant to Lubrol WX, but to a large extent solubilized by Triton X-100. The two additional microdomain markers, reggie-1 and reggie-2, were localized to the basolateral and canalicular plasma membrane and were partially resistant to Lubrol WX but resistant to Triton X-100. The canalicular transporters bile salt export pump, multidrug resistance protein 2, multidrug resistance-associated protein 2, and Abcg5 were largely resistant to Lubrol WX but were solubilized by Triton X-100. These results indicate the presence of two different types of microdomains in the canalicular plasma membrane: "Lubrol-microdomains" and "Triton-microdomains". "Lubrol-microdomains" contain the machinery for canalicular bile formation and may be the starting place for canalicular lipid secretion.

  14. Stabilization of Functional Recombinant Cannabinoid Receptor CB2 in Detergent Micelles and Lipid Bilayers

    PubMed Central

    Vukoti, Krishna; Kimura, Tomohiro; Macke, Laura; Gawrisch, Klaus; Yeliseev, Alexei

    2012-01-01

    Elucidation of the molecular mechanisms of activation of G protein-coupled receptors (GPCRs) is among the most challenging tasks for modern membrane biology. For studies by high resolution analytical methods, these integral membrane receptors have to be expressed in large quantities, solubilized from cell membranes and purified in detergent micelles, which may result in a severe destabilization and a loss of function. Here, we report insights into differential effects of detergents, lipids and cannabinoid ligands on stability of the recombinant cannabinoid receptor CB2, and provide guidelines for preparation and handling of the fully functional receptor suitable for a wide array of downstream applications. While we previously described the expression in Escherichia coli, purification and liposome-reconstitution of multi-milligram quantities of CB2, here we report an efficient stabilization of the recombinant receptor in micelles - crucial for functional and structural characterization. The effects of detergents, lipids and specific ligands on structural stability of CB2 were assessed by studying activation of G proteins by the purified receptor reconstituted into liposomes. Functional structure of the ligand binding pocket of the receptor was confirmed by binding of 2H-labeled ligand measured by solid-state NMR. We demonstrate that a concerted action of an anionic cholesterol derivative, cholesteryl hemisuccinate (CHS) and high affinity cannabinoid ligands CP-55,940 or SR-144,528 are required for efficient stabilization of the functional fold of CB2 in dodecyl maltoside (DDM)/CHAPS detergent solutions. Similar to CHS, the negatively charged phospholipids with the serine headgroup (PS) exerted significant stabilizing effects in micelles while uncharged phospholipids were not effective. The purified CB2 reconstituted into lipid bilayers retained functionality for up to several weeks enabling high resolution structural studies of this GPCR at physiologically relevant conditions. PMID:23056277

  15. Detergent-compatible, organic solvent-tolerant alkaline protease from Bacillus circulans MTCC 7942: Purification and characterization.

    PubMed

    Patil, Ulhas; Mokashe, Narendra; Chaudhari, Ambalal

    2016-01-01

    Proteases are now recognized as the most indispensable industrial biocatalyst owing to their diverse microbial sources and innovative applications. In the present investigation, a thermostable, organic solvent-tolerant, alkaline serine protease from Bacillus circulans MTCC 7942, was purified and characterized. The protease was purified to 37-fold by a three-step purification scheme with 39% recovery. The optimum pH and temperature for protease was 10 and 60 °C, respectively. The apparent molecular mass of the purified enzyme was 43 kD as revealed by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). The Km and Vmax values using casein-substrate were 3.1 mg/mL and 1.8 µmol/min, respectively. The protease remained stable in the presence of organic solvents with higher (>3.2) log P value (cyclohexane, n-octane, n-hexadecane, n-decane, and n-dodecane), as compared to organic solvents with lower (<3.2) log P value (acetone, butanol, benzene, chloroform, toluene). Remarkably, the protease showed profound stability even in the presence of organic solvents with less log P values (glycerol, dimethyl sulfate [DMSO], p-xylene), indicating the possibility of nonaqueous enzymatic applications. Also, protease activity was improved in the presence of metal ions (Ca(2+), Mg(2+), Mn(2+)); enhanced by biosurfactants; hardly affected by bleaching agents, oxidizing agents, and chemical surfactants; and stable in commercial detergents. In addition, a protease-detergent formulation effectively washed out egg and blood stains as compared to detergent alone. The protease was suitable for various commercial applications like processing of gelatinous film and as a compatible additive to detergent formulation with its operative utility in hard water.

  16. Determination of Very Low Level of Free Formaldehyde in Liquid Detergents and Cosmetic Products Using Photoluminescence Method

    PubMed Central

    Mohsenikia, Atefeh; Masoum, Saeed

    2016-01-01

    Formaldehyde is commonly used in detergents and cosmetic products as antibacterial agent and preservative. This substance is unfavorable for human health because it is known to be toxic for humans and causes irritation of eyes and skins. The toxicology studies of this compound indicate risk of detergents and cosmetic formulations with a minimum content of 0.05% free formaldehyde. Therefore, determination of formaldehyde as quality control parameter is very important. In this study, a photoluminescence method was achieved by using 2-methyl acetoacetanilide. Also, the Box-Behnken design was applied for optimization of Hantzsch reaction for formaldehyde derivatization. The investigated factors (variables) were temperature, % v/v ethanol, reaction time, ammonium acetate, and 2-methyl acetoacetanilide concentration. The linear range was obtained from 0.33–20 × 10−7 M (1–60 μg·kg−1) and the limit of detection (LOD) was 0.12 μg·kg−1. The proposed method was applied for the analysis of Iranian brands of liquid detergents and cosmetic products. The formaldehyde content of these products was found to be in the range of 0.03–3.88%. Some brands of these products had higher concentration than the maximum allowed concentration of 0.2%. High recoveries (96.15%–104.82%) for the spiked dishwashing liquid and hair shampoo indicate the proposed method is proper for the assessment of formaldehyde in detergents and cosmetic products. The proposed methodology has some advantages compared with the previous methods such as being rapid, without the necessity of applying separation, low cost, and the fact that the derivatization reaction is carried out at room temperature without any heating system. PMID:27635279

  17. Polyester Textiles as a Source of Microplastics from Households: A Mechanistic Study to Understand Microfiber Release During Washing.

    PubMed

    Hernandez, Edgar; Nowack, Bernd; Mitrano, Denise M

    2017-06-20

    Microplastic fibers make up a large proportion of microplastics found in the environment, especially in urban areas. There is good reason to consider synthetic textiles a major source of microplastic fibers, and it will not diminish since the use of synthetic fabrics, especially polyester, continues to increase. In this study we provide quantitative data regarding the size and mass of microplastic fibers released from synthetic (polyester) textiles during simulated home washing under controlled laboratory conditions. Consideration of fabric structure and washing conditions (use of detergents, temperature, wash duration, and sequential washings) allowed us to study the propensity of fiber shedding in a mechanistic way. Thousands of individual fibers were measured (number, length) from each wash solution to provide a robust data set on which to draw conclusions. Among all the variables tested, the use of detergent appeared to affect the total mass of fibers released the most, yet the detergent composition (liquid or powder) or overdosing of detergent did not significantly influence microplastic release. Despite different release quantities due to the addition of a surfactant (approximately 0.025 and 0.1 mg fibers/g textile washed, without and with detergent, respectively), the overall microplastic fiber length profile remained similar regardless of wash condition or fabric structure, with the vast majority of fibers ranging between 100 and 800 μm in length irrespective of wash cycle number. This indicates that the fiber staple length and/or debris encapsulated inside the fabric from the yarn spinning could be directly responsible for releasing stray fibers. This study serves as a first look toward understanding the physical properties of the textile itself to better understand the mechanisms of fiber shedding in the context of microplastic fiber release into laundry wash water.

  18. Effectiveness of disinfectant wipes for decontamination of bacteria on patients' environmental and medical equipment surfaces at Siriraj Hospital.

    PubMed

    Seenama, Chakkraphong; Tachasirinugune, Peenithi; Jintanothaitavorn, Duangporn; Kachintorn, Kanchana; Thamlikitkul, Visanu

    2013-02-01

    To determine the effectiveness of Virusolve+ disinfectant wipes and PAL disinfectant wipes for decontamination of inoculated bacteria on patients' environmental and medical equipment surfaces at Siriraj Hospital. Tryptic soy broths containing MRSA and XDR A. baumannii were painted onto the surfaces of patient's stainless steel bed rail, patient's fiber footboard, control panel of infusion pump machine and control panel of respirator. The contaminated surfaces were cleaned by either tap water, tap water containing detergent, Virusolve+ disinfectant wipes or PAL disinfectant wipes. The surfaces without any cleaning procedures served as the control surface. The contaminated surfaces cleaned with the aforementioned procedures and control surfaces were swabbed with cotton swabs. The swabs were streaked on agar plates to determine the presence of MRSA and XDR A. baumannii. MRSA and XDR A. baumannii were recovered from all control surfaces. All surfaces cleaned with tap water or tap water containing detergent revealed presence of both MRSA and XDR A. baumannii. However the amounts of bacteria on the surfaces cleaned with tap water containing detergent were less than those cleaned with tap water alone. All surfaces cleaned with PAL disinfectant wipes also revealed presence of both MRSA and XDR A. baumannii. However the amounts of bacteria on the surfaces cleaned with PAL disinfectant wipes were less than those cleaned with tap water containing detergent. No bacteria were recovered from all surfaces cleaned with Virusolve+ disinfectant wipes. Virusolve+ disinfectant wipes were more effective than tap water; tap water containing detergent and PAL disinfectant wipes for decontamination of bacteria inoculated on patients environmental and medical equipment surfaces at Siriraj Hospital.

  19. FOLDING OF DIPHTHERIA TOXIN T-DOMAIN IN THE PRESENCE OF AMPHIPOLS AND FLUORINATED SURFACTANTS: TOWARD THERMODYNAMIC MEASUREMENTS OF MEMBRANE PROTEIN FOLDING

    PubMed Central

    Kyrychenko, Alexander; Rodnin, Mykola V.; Vargas-Uribe, Mauricio; Sharma, Shivaji K.; Durand, Grégory; Pucci, Bernard; Popot, Jean-Luc; Ladokhin, Alexey S.

    2011-01-01

    Solubilizing membrane proteins for functional, structural and thermodynamic studies is usually achieved with the help of detergents, which tend to destabilize them, however. Several classes of non-detergent surfactants have been designed as milder substitutes for detergents, most prominently amphipathic polymers called 'amphipols' and fluorinated surfactants. Here we test the potential usefulness of these compounds for thermodynamic studies by examining their effect on conformational transitions of the diphtheria toxin T-domain. The advantage of the T-domain as a model system is that it exists as a soluble globular protein at neutral pH yet is converted into a membrane-competent form by acidification and inserts into the lipid bilayer as part of its physiological action. We have examined the effects of various surfactants on two conformational transitions of the T-domain, thermal unfolding and pH-induced transition to a membrane-competent form. All tested detergent and non-detergent surfactants lowered the cooperativity of the thermal unfolding of the T-domain. The dependence of enthalpy of unfolding on surfactant concentration was found to be least for fluorinated surfactants, thus making them useful candidates for thermodynamic studies. Circular dichroism measurements demonstrate that non-ionic homo-polymeric amphipols (NAhPols), unlike any other surfactants, can actively cause a conformational change of the T-domain. NAhPol-induced structural rearrangements are different from those observed during thermal denaturation and are suggested to be related to the formation of the membrane-competent form of the T-domain. Measurements of vesicle content leakage indicate that interaction with NAhPols not only does not prevent the T-domain from inserting into the bilayer, but it can make bilayer permeabilization even more efficient, whereas the pH-dependence of membrane permeabilization becomes more cooperative. PMID:21945883

  20. Improving thermal and detergent stability of Bacillus stearothermophilus neopullulanase by rational enzyme design.

    PubMed

    Ece, Selin; Evran, Serap; Janda, Jan-Oliver; Merkl, Rainer; Sterner, Reinhard

    2015-06-01

    Neopullulanase, a glycosyl hydrolase from Bacillus stearothermophilus (bsNpl), is a potentially valuable enzyme for starch and detergent industries. However, as the protein is not active at elevated temperatures and high surfactant concentrations, we aimed to increase its stability by rational enzyme design. Nine potentially destabilizing cavities were identified in the crystal structure of the enzyme. Based on computational predictions, these cavities were filled by residues with bulkier side chains. The five Asp46Glu, Val239Leu, Val404Leu, Ser407Thr and Ala566Leu exchanges resulted in a drastic stabilization of bsNpl against inactivation by heat and detergents. The catalytic activity of the variants was identical to the wild-type enzyme. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  1. Maltose-neopentyl glycol (MNG) amphiphiles for solubilization, stabilization and crystallization of membrane proteins.

    PubMed

    Chae, Pil Seok; Rasmussen, Søren G F; Rana, Rohini R; Gotfryd, Kamil; Chandra, Richa; Goren, Michael A; Kruse, Andrew C; Nurva, Shailika; Loland, Claus J; Pierre, Yves; Drew, David; Popot, Jean-Luc; Picot, Daniel; Fox, Brian G; Guan, Lan; Gether, Ulrik; Byrne, Bernadette; Kobilka, Brian; Gellman, Samuel H

    2010-12-01

    The understanding of integral membrane protein (IMP) structure and function is hampered by the difficulty of handling these proteins. Aqueous solubilization, necessary for many types of biophysical analysis, generally requires a detergent to shield the large lipophilic surfaces of native IMPs. Many proteins remain difficult to study owing to a lack of suitable detergents. We introduce a class of amphiphiles, each built around a central quaternary carbon atom derived from neopentyl glycol, with hydrophilic groups derived from maltose. Representatives of this maltose-neopentyl glycol (MNG) amphiphile family show favorable behavior relative to conventional detergents, as manifested in multiple membrane protein systems, leading to enhanced structural stability and successful crystallization. MNG amphiphiles are promising tools for membrane protein science because of the ease with which they may be prepared and the facility with which their structures may be varied.

  2. Characterization of thermo- and detergent stable antigenic glycosylated cysteine protease of Euphorbia nivulia Buch.-Ham. and evaluation of its ecofriendly applications.

    PubMed

    Badgujar, Shamkant B; Mahajan, Raghunath T

    2013-01-01

    An antigenic glycosylated cysteine protease has been purified from the latex of Euphorbia nivulia Buch.-Ham. It exhibits remarkable protease activity in the presence of metal ions, oxidizing agents, organic solvents, and detergents. This enzyme showed potential role in leather processing industry due to its dehairing activity for animal hide without hydrolyzing fibrous proteins, producing, by this way, a better quality product. The enzyme can also be used for silver recovering from X-ray plates. In addition, the stability (temperature and surfactants) and hydrolysis of blood stain data also revealed its application in detergent industries. Agriculturally, this protease finds application in biocontrol process against the infectious management of root knot nematode, Meloidogyne incognita. Biologically, it shows noticeable wound healing, haemostatic and antibacterial activity.

  3. Characterization of Thermo- and Detergent Stable Antigenic Glycosylated Cysteine Protease of Euphorbia nivulia Buch.-Ham. and Evaluation of Its Ecofriendly Applications

    PubMed Central

    Badgujar, Shamkant B.; Mahajan, Raghunath T.

    2013-01-01

    An antigenic glycosylated cysteine protease has been purified from the latex of Euphorbia nivulia Buch.-Ham. It exhibits remarkable protease activity in the presence of metal ions, oxidizing agents, organic solvents, and detergents. This enzyme showed potential role in leather processing industry due to its dehairing activity for animal hide without hydrolyzing fibrous proteins, producing, by this way, a better quality product. The enzyme can also be used for silver recovering from X-ray plates. In addition, the stability (temperature and surfactants) and hydrolysis of blood stain data also revealed its application in detergent industries. Agriculturally, this protease finds application in biocontrol process against the infectious management of root knot nematode, Meloidogyne incognita. Biologically, it shows noticeable wound healing, haemostatic and antibacterial activity. PMID:24348183

  4. Deoxycholate-Based Glycosides (DCGs) for Membrane Protein Stabilisation.

    PubMed

    Bae, Hyoung Eun; Gotfryd, Kamil; Thomas, Jennifer; Hussain, Hazrat; Ehsan, Muhammad; Go, Juyeon; Loland, Claus J; Byrne, Bernadette; Chae, Pil Seok

    2015-07-06

    Detergents are an absolute requirement for studying the structure of membrane proteins. However, many conventional detergents fail to stabilise denaturation-sensitive membrane proteins, such as eukaryotic proteins and membrane protein complexes. New amphipathic agents with enhanced efficacy in stabilising membrane proteins will be helpful in overcoming the barriers to studying membrane protein structures. We have prepared a number of deoxycholate-based amphiphiles with carbohydrate head groups, designated deoxycholate-based glycosides (DCGs). These DCGs are the hydrophilic variants of previously reported deoxycholate-based N-oxides (DCAOs). Membrane proteins in these agents, particularly the branched diglucoside-bearing amphiphiles DCG-1 and DCG-2, displayed favourable behaviour compared to previously reported parent compounds (DCAOs) and conventional detergents (LDAO and DDM). Given their excellent properties, these agents should have significant potential for membrane protein studies. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Novel System for Testing Dermal and Epidermal Toxicity in Vitro

    DTIC Science & Technology

    1990-02-15

    of sodium dodecyl sulfate (SDS) were performed to set standard dose curves. The following procedure resulted frcm this pilot study: MODIFIED TOTAL...Detergent Association (SDA), commercial shampoos and household agents. These results were reproducible and could be correlated, in general, with in vivo...Detergents 2. Common household products and shampoos 3. Alcohols Page 24 4. Petrochemicals 5. Preservatives The substrate was also adapted for use in

  6. Chemical Sanitation System for Pots and Pans in Field Operations

    DTIC Science & Technology

    1989-02-01

    cleanup would be advantageous to the military. In an arid environment water is a scarce commodity and must be conserved; detergent/sanitizer that cleans...sanitation system was to evaluate ommercially available detergent/sanitizers having Environmental Protetion Agency (EPA) and Food and Drug...Iodophor 99.92 Iodine omplex Not Available Scrub/Brush EZ Hibiclens 94.27 Chlohexidine " " gluconate Cleaf 300 Soap Leaf 91.25 Triclosan Paraciem Corp

  7. Profile of irritant patch testing with detergents: sodium lauryl sulfate, sodium laureth sulfate and alkyl polyglucoside.

    PubMed

    Löffler, H; Happle, R

    2003-01-01

    The cutaneous reaction to detergents follows distinct kinetic rules: the duration of application and the irritant concentration are of major importance. The aim of this study was to evaluate the differences in kinetics of skin reaction between the standard irritant sodium lauryl sulfate (SLS), and 2 modern detergents: sodium laureth sulfate (SLES) and alkyl polyglucoside (APG). We performed patch testing with SLS and SLES (or APG) at different concentrations (0.125, 0.25, 0.5, 1.0 and 2.0%) and with different exposure times (6, 12 and 24 h). Evaluation was conducted by measurement of transepidermal water loss (TEWL) and laser Doppler flowmetry (LD) 24 h, 7 and 10 days after patch removal. We found a pronounced reaction to SLS, and a far milder one to SLES. Even at the highest concentration the skin reaction to APG was hard to detect. During the regeneration period (day 3-10) SLS showed even at day 10 an increased TEWL at all concentrations tested. The irritation due to SLES was convincingly detectable only up to day 7, whereas the APG-tested skin areas showed no significant reaction even at day 3. These results demonstrate the improvement in reduction of skin irritation achieved by development of novel detergents.

  8. Identification of Poly(ethylene glycol) and Poly(ethylene glycol)-Based Detergents Using Peptide Search Engines.

    PubMed

    Ahmadi, Shiva; Winter, Dominic

    2018-06-05

    Poly(ethylene glycol) (PEG) is one of the most common polymer contaminations in mass spectrometry (MS) samples. At present, the detection of PEG and other polymers relies largely on manual inspection of raw data, which is laborious and frequently difficult due to sample complexity and retention characteristics of polymer species in reversed-phase chromatography. We developed a new strategy for the automated identification of PEG molecules from tandem mass spectrometry (MS/MS) data using protein identification algorithms in combination with a database containing "PEG-proteins". Through definition of variable modifications, we extend the approach for the identification of commonly used PEG-based detergents. We exemplify the identification of different types of polymers by static nanoelectrospray tandem mass spectrometry (nanoESI-MS/MS) analysis of pure detergent solutions and data analysis using Mascot. Analysis of liquid chromatography-tandem mass spectrometry (LC-MS/MS) runs of a PEG-contaminated sample by Mascot identified 806 PEG spectra originating from four PEG species using a defined set of modifications covering PEG and common PEG-based detergents. Further characterization of the sample for unidentified PEG species using error-tolerant and mass-tolerant searches resulted in identification of 3409 and 3187 PEG-related MS/MS spectra, respectively. We further demonstrate the applicability of the strategy for Protein Pilot and MaxQuant.

  9. Fluorinated diglucose detergents for membrane-protein extraction.

    PubMed

    Boussambe, Gildas Nyame Mendendy; Guillet, Pierre; Mahler, Florian; Marconnet, Anaïs; Vargas, Carolyn; Cornut, Damien; Soulié, Marine; Ebel, Christine; Le Roy, Aline; Jawhari, Anass; Bonneté, Françoise; Keller, Sandro; Durand, Grégory

    2018-05-29

    Fluorinated surfactants have scarcely been explored for the direct extraction of proteins from membranes because fluorination is believed to abrogate detergency. However, we have recently shown that a commercially available fluorinated surfactant readily solubilizes lipid membranes, thereby suggesting that fluorination per se does not interfere with detergent activity. In this work, we developed new fluorinated surfactants that exhibit detergency in terms of both lipid-vesicle solubilization and membrane-protein extraction. The compounds made and tested contain two glucose moieties as polar headgroup, a hydrogenated thioether linker, and a perfluorinated alkyl tail with either 4, 6, or 8 carbon atoms. The physicochemical properties of the micelles formed by the three fluorinated surfactants were evaluated by NMR spectroscopy, surface tensiometry, isothermal titration calorimetry, dynamic light scattering, small-angle X-ray scattering, and analytical ultracentrifugation. At 25°C, micellization was mainly entropy-driven, and the CMC values were found to decrease with chain length of the fluorinated tail, whereas the aggregation number increased with chain length. Remarkably, all three surfactants were found to solubilize lipid vesicles and extract a broad range of proteins from Escherichiacoli membranes. These findings demonstrate, for the first time, that nonionic fluorinated surfactants could be further exploited for the direct extraction and solubilization of membrane proteins. Copyright © 2018. Published by Elsevier Inc.

  10. Application of amphipols for structure-functional analysis of TRP channels.

    PubMed

    Huynh, Kevin W; Cohen, Matthew R; Moiseenkova-Bell, Vera Y

    2014-10-01

    Amphipathic polymers (amphipols), such as A8-35 and SApol, are a new tool for stabilizing integral membrane proteins in detergent-free conditions for structural and functional studies. Transient receptor potential (TRP) ion channels function as tetrameric protein complexes in a diverse range of cellular processes including sensory transduction. Mammalian TRP channels share ~20 % sequence similarity and are categorized into six subfamilies: TRPC (canonical), TRPV (vanilloid), TRPA (ankyrin), TRPM (melastatin), TRPP (polycystin), and TRPML (mucolipin). Due to the inherent difficulties in purifying eukaryotic membrane proteins, structural studies of TRP channels have been limited. Recently, A8-35 was essential in resolving the molecular architecture of the nociceptor TRPA1 and led to the determination of a high-resolution structure of the thermosensitive TRPV1 channel by cryo-EM. Newly developed maltose-neopentyl glycol (MNG) detergents have also proven to be useful in stabilizing TRP channels for structural analysis. In this review, we will discuss the impacts of amphipols and MNG detergents on structural studies of TRP channels by cryo-EM. We will compare how A8-35 and MNG detergents interact with the hydrophobic transmembrane domains of TRP channels. In addition, we will discuss what these cryo-EM studies reveal on the importance of screening different types of surfactants toward determining high-resolution structures of TRP channels.

  11. Effect of Detergents on Galactoside Binding by Melibiose Permeases.

    PubMed

    Amin, Anowarul; Hariharan, Parameswaran; Chae, Pil Seok; Guan, Lan

    2015-09-29

    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.

  12. Application of amphipols for structure-functional analysis of TRP channels

    PubMed Central

    Huynh, Kevin W.; Cohen, Matthew R.; Moiseenkova-Bell, Vera Y.

    2014-01-01

    Amphipathic polymers (amphipols), such as A8-35 and SApol, are a new tool for stabilizing integral membrane proteins in detergent-free conditions for structural and functional studies. Transient receptor potential (TRP) ion channels function as tetrameric protein complexes in a diverse range of cellular processes including sensory transduction. Mammalian TRP channels share ~20% sequence similarity and are categorized into six subfamilies: TRPC (canonical), TRPV (vanilloid), TRPA (ankyrin), TRPM (melastatin), TRPP (polycystin), and TRPML (mucolipin). Due to the inherent difficulties in purifying eukaryotic membrane proteins, structural studies of TRP channels have been limited. Recently, A8-35 was essential in resolving the molecular architecture of the nociceptor TRPA1 and led to the determination of a high resolution structure of the thermosensitive TRPV1 channel by cryo-EM. Newly developed maltose-neopentyl glycol (MNG) detergents have also proven useful in stabilizing TRP channels for structural analysis. In this review, we will discuss the impact of amphipols and MNG detergents on structural studies of TRP channels by cryo-EM. We will compare how A8-35 and MNG detergents interact with the hydrophobic transmembrane (TM) domains of TRP channels. In addition, we will discuss what these cryo-EM studies reveal on the importance of screening different types of surfactants towards determining high resolution structures of TRP channels. PMID:24894720

  13. Effect of detergents on galactoside binding by melibiose permeases

    PubMed Central

    Amin, Anowarul; Hariharan, Parameswaran; Chae, Pil Seok; Guan, Lan

    2015-01-01

    The effect of various detergents on the stability and function of melibiose permeases of Escherichia coli (MelBEc) or Salmonella typhimurium (MelBSt) were 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 IIAGlc is maintained. In the amphiphiles lauryl maltose neopentyl glycol (MNG-3) or glyco-diosgenin (GDN), galactoside binding with all 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 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. PMID:26352464

  14. Association of a GPI-anchored protein with detergent-resistant membranes facilitates its trafficking through the early secretory pathway.

    PubMed

    Hein, Zeynep; Hooper, Nigel M; Naim, Hassan Y

    2009-01-15

    Membrane microdomains are implicated in the trafficking and sorting of several membrane proteins. In particular GPI-anchored proteins cluster into Triton X-100 resistant, cholesterol- and sphingolipid-rich membrane microdomains and are sorted to the apical membrane. A growing body of evidence has pointed to the existence of other types of microdomains that are insoluble in detergents, such as Lubrol WX and Tween-20. Here, we report on the role of detergent-resistant membranes formed at early stages in the biosynthesis of membrane dipeptidase (MDP), a GPI-anchored protein, on its trafficking and sorting. Pulse-chase experiments revealed a retarded maturation rate of the GPI-anchor deficient mutant (MDPDeltaGPI) as compared to the wild type protein (wtMDP). However, Golgi to cell surface delivery rate did not show a significant difference between the two variants. On the other hand, early biosynthetic forms of wtMDP were partially insoluble in Tween-20, while MDPDeltaGPI was completely soluble. The lack of association of MDPDeltaGPI with detergent-resistant membranes prior to maturation in the Golgi and the reduction in its trafficking rate strongly suggest the existence of an early trafficking control mechanisms for membrane proteins operating at a level between the endoplasmic reticulum and the cis-Golgi.

  15. Synthesis of methyl ester sulfonate surfactant from crude palm oil as an active substance of laundry liquid detergent

    NASA Astrophysics Data System (ADS)

    Slamet, Ibadurrohman, Muhammad; Wulandari, Pangiastika Putri

    2017-11-01

    Liquid detergent with combination of MES surfactant and TiO2 nanoparticles to remove and degrade the dirt in the form of methylene blue and produce waste with the lowest surfactant residual concentration has been done. The formation of MES is carried out by esterification and transesterification of crude palm oil, sulfonation, refining, and neutralization. The photocatalyst TiO2 nanoparticles is added as an additive to improve surfactant performance in removing dirt and degrading organic compounds. MES formation is performed by varying the mole ratio of the reactants in the esterification and transesterification reactions, and the mole ratios between methyl esters and NaHSO3 during the sulfonation reaction. Variations of MES surfactant and TiO2 nanoparticles compositions were performed to obtain detergent stability. Data analysis technique in this research is characterization of methyl ester, MES surfactant, and detergent using UV-Vis spectrophotometer instrument, FTIR, GC-MS, and LC-MS. The optimum conditions in the esterification and transesterification process were each mole ratio of 1: 6 between CPO and methanol based on the highest conversion, 99%. The optimum condition of the sulfonation process is the 1: 1.5 mole ratio between methyl ester and NaHSO3 based on the lowest surface tension value, which is about 36 dyne/cm.

  16. Non-ionic detergents facilitate non-specific binding of M13 bacteriophage to polystyrene surfaces.

    PubMed

    Hakami, Abdulrahim R; Ball, Jonathan K; Tarr, Alexander W

    2015-09-01

    Phage-displayed random peptide libraries are widely used for identifying peptide interactions with proteins and other substrates. Selection of peptide ligands involves iterative rounds of affinity enrichment. The binding properties of the selected phage clones are routinely tested using immunoassay after propagation to high titre in a bacterial host and precipitation using polyethylene glycol (PEG) and high salt concentration. These immunoassays can suffer from low sensitivity and high background signals. Polysorbate 20 (Tween(®) 20) is a non-ionic detergent commonly used in immunoassay washing buffers to reduce non-specific binding, and is also used as a blocking reagent. We have observed that Tween 20 enhances non-specific M13 library phage binding in a peptide-independent manner. Other non-ionic detergents were also found to promote significant, dose-dependent non-specific phage binding in ELISA. This effect was not observed for assays using phage concentrated by ultracentrifugation, suggesting that interactions occur between detergents and the PEG-precipitated phage, irrespective of the displayed peptide motif. This artefact may impact on successful affinity selection of peptides from phage-display libraries. We propose alternative methods for screening phage libraries for identifying binding interactions with target ligands. Copyright © 2015 Elsevier B.V. All rights reserved.

  17. Oregano essential oil as an antimicrobial additive to detergent for hand washing and food contact surface cleaning.

    PubMed

    Rhoades, J; Gialagkolidou, K; Gogou, M; Mavridou, O; Blatsiotis, N; Ritzoulis, C; Likotrafiti, E

    2013-10-01

    To investigate the potential use of oregano essential oil as an antimicrobial agent in liquid soap for hand washing and for food contact surface cleaning. Oregano essential oil (O.E.O.) was emulsified in liquid detergent solution. This was challenge tested against a commercial antimicrobial soap in hand washing trials using natural flora. Soap with O.E.O. was as effective as the commercial antimicrobial soap at reducing aerobic plate count on the hands and more effective than plain soap with no additives. Cloths wetted with soap with O.E.O. were used to clean three different surfaces contaminated with four bacterial pathogens. For three of the four pathogens, the addition of 0·5% v/v O.E.O. to the soap solution enhanced cleaning performance and also reduced bacterial survival on the cloth after cleaning. Oregano essential oil (0·5%) is effective as an antimicrobial additive to detergent solutions for hand washing and surface cleaning. This preliminary study has shown that oregano essential oil is a potential alternative to antimicrobials used in various detergents, such as chloroxylenol and triclosan, which can have adverse environmental and health effects. Further development could lead to a commercial product. © 2013 The Society for Applied Microbiology.

  18. Bioprocessing of "Hair Waste" by Paecilomyces lilacinus as a Source of a Bleach-Stable, Alkaline, and Thermostable Keratinase with Potential Application as a Laundry Detergent Additive: Characterization and Wash Performance Analysis.

    PubMed

    Cavello, Ivana A; Hours, Roque A; Cavalitto, Sebastián F

    2012-01-01

    Paecilomyces lilacinus (Thom) Samson LPS 876, a locally isolated fungal strain, was grown on minimal mineral medium containing "hair waste," a residue from the hair-saving unhairing process, and produced a protease with keratinolytic activity. This enzyme was biochemically characterized. The optimum reaction conditions, determined with a response surface methodology, were 60°C and pH 6.0. It was remarkably stable in a wide range of pHs and temperatures. Addition of Ca(2+), Mg(2+), or sorbitol was found to be effective in increasing thermal stability of the protease. PMSF and Hg(2+) inhibited the proteolytic activity indicating the presence of a thiol-dependent serine protease. It showed high stability toward surfactants, bleaching agents, and solvents. It was also compatible with commercial detergents (7 mg/mL) such as Ariel, Skip, Drive, and Ace, retaining more than 70% of its proteolytic activity in all detergents after 1 h of incubation at 40°C. Wash performance analysis revealed that this protease could effectively remove blood stains. From these properties, this enzyme may be considered as a potential candidate for future use in biotechnological processes, as well as in the formulation of laundry detergents.

  19. Ultrastructural analysis of v-myb oncogene product cooperation with components of avian cell nuclear matrix.

    PubMed

    Korb, J; Stokrová, J; Karafiát, V

    2000-01-01

    The cooperation of the v-Myb oncoprotein with extracted nuclear matrix of avian haematopoietic cells expressing the v-myb oncogene was studied by means of immunoelectron microscopy. The nuclear matrix was extracted by a gentle method of detergent treatment at moderate ionic strength and visualized either in ultrathin LR White sections, in unembedded resin-free sections, and in addition by the aqueous spreading technique. Using anti-Myb polyclonal antibody we have shown interaction of the v-Myb protein product with extracted nuclear matrix. This oncoprotein, however, was easily released from the structure by a detergent as well as by DNAase treatment and ammonium sulphate extraction. Prefixation of structures before detergent treatment prevented this extraction. The v-Myb protein marker was distributed in clusters or associated with fibrillar structures in most cases. Single markers decorating these fibrillar or less dense structures were also detected.

  20. CHOBIMALT: A Cholesterol-Based Detergent†

    PubMed Central

    Howell, Stanley C.; Mittal, Ritesh; Huang, Lijun; Travis, Benjamin; Breyer, Richard M.; Sanders, Charles R.

    2010-01-01

    Cholesterol and its hemisuccinate and sulfate derivatives are widely used in studies of purified membrane proteins, but are difficult to solubilize in aqueous solution, even in the presence of detergent micelles. Other cholesterol derivatives do not form conventional micelles and lead to viscous solutions. To address these problems a cholesterol-based detergent, CHOBIMALT, has been synthesized and characterized. At concentrations above 3–4μM, CHOBIMALT forms micelles without the need for elevated temperatures or sonic disruption. Diffusion and fluorescence measurements indicated that CHOBIMALT micelles are large (210 ± 30 kDa). The ability to solubilize a functional membrane protein was explored using a G-protein coupled receptor, the human kappa opioid receptor type 1 (hKOR1). While CHOBIMALT alone was not found to be effective as a surfactant for membrane extraction, when added to classical detergent micelles CHOBIMALT was observed to dramatically enhance the thermal stability of solubilized hKOR1. PMID:20919740

  1. Comparison of the fluorescence kinetics of detergent-solubilized and membrane-reconstituted LH2 complexes from Rps. acidophila and Rb. sphaeroides.

    PubMed

    Pflock, Tobias; Dezi, Manuela; Venturoli, Giovanni; Cogdell, Richard J; Köhler, Jürgen; Oellerich, Silke

    2008-01-01

    Picosecond time-resolved fluorescence spectroscopy has been used in order to compare the fluorescence kinetics of detergent-solubilized and membrane-reconstituted light-harvesting 2 (LH2) complexes from the purple bacteria Rhodopseudomonas (Rps.) acidophila and Rhodobacter (Rb.) sphaeroides. LH2 complexes were reconstituted in phospholipid model membranes at different lipid:protein-ratios and all samples were studied exciting with a wide range of excitation densities. While the detergent-solubilized LH2 complexes from Rps. acidophila showed monoexponential decay kinetics (tau(f )= 980 ps) for excitation densities of up to 3.10(13) photons/(pulse.cm(2)), the membrane-reconstituted LH2 complexes showed multiexponential kinetics even at low excitation densities and high lipid:protein-ratios. The latter finding indicates an efficient clustering of LH2 complexes in the phospholipid membranes. Similar results were obtained for the LH2 complexes from Rb. sphaeroides.

  2. An impedimetric chemical sensor for determination of detergents residues.

    PubMed

    Bratov, Andrey; Abramova, Natalia; Ipatov, Andrey; Merlos, Angel

    2013-03-15

    A new impedimetric sensor based on an interdigitated electrode array with electrode digits located at the bottom of microcapillaries formed in silicon dioxide is presented. Microcapillaries are opened at the top, so that in contact with an electrolyte solution the ac current flows close to the surface of the capillary wall from one electrode to another and is significantly affected by changes in the surface conductance at the SiO2/electrolyte interface. Adsorption of detergents on the sensor surface affects the charge distribution in the electrical double layer and thus the surface conductance. These changes are registered by measuring impedance. Effect of surface adsorption of ionic and non-ionic surfactants on the sensor impedance is studied. The sensor is shown to be able to measure commercial detergents residues in a tap water starting from 5 ppm even in solutions with high electrolyte conductivity. Copyright © 2012 Elsevier B.V. All rights reserved.

  3. Guide to resource conservation and cost savings opportunities in the soap, detergents and related products sector

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    NONE

    1998-10-01

    This guide was prepared to help those involved in the manufacturing of soap, detergent, and related products to identify potential process improvements that will reduce production costs and conserve resources. The guide offers a series of generic process descriptions and checklists of improvement opportunities specific to each of five major processes used in the industry: Soap production, surfactant production, solid cake product formulation, liquid product formulation, and granulated powdered product formulation. The checklists identify thermal, electrical, environmental, water use, and low- or no-cost measures that can be implemented, as well as retrofit technology options. A variety of new technologies thatmore » may exhibit future potential are also described. Appendices include a glossary, background information on the Ontario soap/detergent industry, and description of the four major categories of ingredients used in the industry.« less

  4. Non-detergent sulphobetaines: a new class of molecules that facilitate in vitro protein renaturation.

    PubMed

    Goldberg, M E; Expert-Bezançon, N; Vuillard, L; Rabilloud, T

    1996-01-01

    Attempts to renature proteins often yield aggregates rather than native protein. To minimize aggregation, low protein concentrations and/or solubilizing agents are used. Here, we test new solubilizing molecules, non-detergent sulphobetaines, to improve the renaturation of two very different enzymes, hen egg white lysozyme and bacterial beta-D-galactosidase. The renaturation was conducted in the presence of five different sulphobetaines and the yield of active enzyme was measured. The five sulphobetaines improved the yield of native lysozyme up to 12-fold. Some sulphobetaines improved the yield of galactosidase up to 80-fold, but one reduced it 100-fold. Non-detergent sulphobetaines strongly affect the balance between aggregation and folding. Their effect depends on their structure and on their interactions with folding intermediates. These results should serve as a basis for designing more efficient sulphobetaines; for designing improved renaturation protocols using existing sulphobetaines; and for characterizing folding intermediates that interact with sulphobetaines.

  5. Maltose-neopentyl glycol (MNG) amphiphiles for solubilization, stabilization and crystallization of membrane proteins

    PubMed Central

    Chae, Pil Seok; Rasmussen, Søren G. F.; Rana, Rohini; Gotfryd, Kamil; Chandra, Richa; Goren, Michael A.; Kruse, Andrew C.; Nurva, Shailika; Loland, Claus J.; Pierre, Yves; Drew, David; Popot, Jean-Luc; Picot, Daniel; Fox, Brian G.; Guan, Lan; Gether, Ulrik; Byrne, Bernadette; Kobilka, Brian; Gellman, Samuel H.

    2011-01-01

    The understanding of integral membrane protein (IMP) structure and function is hampered by the difficulty of handling these proteins. Aqueous solubilization, necessary for many types of biophysical analysis, generally requires a detergent to shield the large lipophilic surfaces displayed by native IMPs. Many proteins remain difficult to study owing to a lack of suitable detergents. We introduce a class of amphiphiles, each of which is built around a central quaternary carbon atom derived from neopentyl glycol, with hydrophilic groups derived from maltose. Representatives of this maltose-neopentyl glycol (MNG) amphiphile family display favorable behavior relative to conventional detergents, as tested on multiple membrane protein systems, leading to enhanced structural stability and successful crystallization. MNG amphiphiles are promising tools for membrane protein science because of the ease with which they may be prepared and the facility with which their structures may be varied. PMID:21037590

  6. Control of acid drainage from fresh coal refuse: food preservatives as economical alternatives to detergents

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Onysko, S.J.; Erickson, P.M.; Kleinmann, R.L.P.

    Water soluble detergents such as sodium lauryl sulfate (SLS), which can sorb to pyritic materials, have been successfully used by the mining industry for acid drainage prevention in coal refuse. Detergent control of acid drainage from refuse may be uneconomical, however, at sites where extensive rainfall or groundwater movement results in rapid SLS washout. In this study, the performance of two alternative acid control chemicals, sodium benzoate and potassium sorbate, was compared with the performance of SLS in pilot-scale experiments with extensively leached, fresh coal refuse. Chemical cost information is presented that indicates low benzoate and sorbate doses were moremore » economical than comparable SLS doses under the experimental conditions of the study. The unique environmental compatibility of benzoate and sorbate, which are used in food and beverages in concentrations greater than those reported in this study for acid drainage suppression, is also discussed.« less

  7. Fundamental studies of glucose oxidase deposition on a Pt electrode.

    PubMed

    Matsumoto, Norio; Chen, Xiaohong; Wilson, George S

    2002-01-15

    The direct electrodeposition of glucose oxidase (EC 1.1.3.4) on a platinum electrode was investigated as a means for controlled immobilization. The presence of a nonionic detergent, Triton X-100, was found essential to produce a multilayered deposit. Moreover, to work properly, the detergent must be present above its critical micelle concentration. Under these conditions, a deposit of approximately 50 enzyme layers (480 nm), with surface uniformity of +/-20 nm, was verified using an electrochemical quartz crystal microbalance and by atomic force microscopy. In the absence of detergent, a layer of 25 nm is formed. Contrary to most previous claims, the deposition, which is potential dependent but optimal at 1.3 V versus AgCl/Ag electrode, is not electrophoretically driven, but is instead controlled by a lowering of the pH at the electrode surface due to concomitant oxygen evolution.

  8. The cleaning of instruments and syringes

    PubMed Central

    Darmady, E. M.; Hughes, K. E. A.; Drewett, S. E.; Prince, D.; Tuke, Winifred; Verdon, Patricia

    1965-01-01

    The dangers to the handler of syringes used for routine injections were found to be negligible, but known infected syringes and those contaminated with antibiotics should be autoclaved before handling as a high proportion of these carry pathogenic organisms. Mechanical methods of cleaning syringes and instruments are assessed. The use of an artificial soil for testing purposes is described. Using this soil, ultrasonics by themselves are inadequate for cleaning syringes and instruments. Agitation with ultrasonics is essential for syringes, but is insufficient for instruments. Detergents are therefore an essential adjunct to the cleaning process. For syringes Pyroneg proved to be the most satisfactory, particularly if they had been previously siliconized. The best detergent for instruments contaminated with these types of soil was Penesolve 814 at a temperature of 95°C. but the instruments must be adequately rinsed after this treatment. A number of other detergents and cleaning agents are discussed. PMID:14247708

  9. Fast and accurate determination of the detergent efficiency by optical fiber sensors

    NASA Astrophysics Data System (ADS)

    Patitsa, Maria; Pfeiffer, Helge; Wevers, Martine

    2011-06-01

    An optical fiber sensor was developed to control the cleaning efficiency of surfactants. Prior to the measurements, the sensing part of the probe is covered with a uniform standardized soil layer (lipid multilayer), and a gold mirror is deposited at the end of the optical fiber. For the lipid multilayer deposition on the fiber, Langmuir-Blodgett technique was used and the progress of deposition was followed online by ultraviolet spectroscopy. The invention provides a miniaturized Surface Plasmon Resonance dip-sensor for automated on-line testing that can replace the cost and time consuming existing methods and develop a breakthrough in detergent testing in combining optical sensing, surface chemistry and automated data acquisition. The sensor is to be used to evaluate detergency of different cleaning products and also indicate how formulation, concentration, lipid nature and temperature affect the cleaning behavior of a surfactant.

  10. Molecular organization and dynamics of micellar phase of polyelectrolyte-surfactant complexes: ESR spin probe study

    NASA Astrophysics Data System (ADS)

    Wasserman, A. M.; Kasaikin, V. A.; Zakharova, Yu. A.; Aliev, I. I.; Baranovsky, V. Yu.; Doseva, V.; Yasina, L. L.

    2002-04-01

    Molecular dynamics and organization of the micellar phase of complexes of linear polyelectrolytes with ionogenic and non-ionogenic surfactants was studied by the ESR spin probe method. Complexes of polyacrylic acid (PAA) and sodium polystyrenesulfonate (PSS) with alkyltrimethylammonium bromides (ATAB), as well as complexes of poly- N, N'-dimethyldiallylammonium chloride (PDACL) with sodium dodecylsulfate (SDS) were studied. The micellar phase of such complexes is highly organized molecular system, molecular ordering of which near the polymeric chain is much higher than in the 'center' of the micelle, it depends on the polymer-detergent interaction, flexibility of polymeric chain and length of carbonic part of the detergent molecule. Complexes of polymethacrylic acid (PMAA) with non-ionic detergent (dodecyl-substituted polyethyleneglycol), show that the local mobility of surfactant in such complexes is significantly lower than in 'free' micelles and depends on the number of micellar particles participating in formation of complexes.

  11. Fire extinguishing tests -80 with methyl alcohol gasoline

    NASA Astrophysics Data System (ADS)

    Holmstedt, G.; Ryderman, A.; Carlsson, B.; Lennmalm, B.

    1980-10-01

    Large scale tests and laboratory experiments were carried out for estimating the extinguishing effectiveness of three alcohol resistant aqueous film forming foams (AFFF), two alcohol resistant fluoroprotein foams and two detergent foams in various poolfires: gasoline, isopropyl alcohol, acetone, methyl-ethyl ketone, methyl alcohol and M15 (a gasoline, methyl alcohol, isobutene mixture). The scaling down of large scale tests for developing a reliable laboratory method was especially examined. The tests were performed with semidirect foam application, in pools of 50, 11, 4, 0.6, and 0.25 sq m. Burning time, temperature distribution in the liquid, and thermal radiation were determined. An M15 fire can be extinguished with a detergent foam, but it is impossible to extinguish fires in polar solvents, such as methyl alcohol, acetone, and isopropyl alcohol with detergent foams, AFFF give the best results; and performances with small pools can hardly be correlated with results from large scale fires.

  12. Isotopic nitrogen in fecal fiber as an indicator of winter diet in caribou and muskoxen

    USGS Publications Warehouse

    Gustine, David D.; Barboza, Perry S.; Addison, Jennifer; Shively, Rachel; Oliver, Lola

    2014-01-01

    RATIONALE: The ratios of stable nitrogen isotopes (δ15N values) in excreta have been used to examine aspects of trophic and nutritional ecology across taxa. Nitrogen fractions in feces of herbivores include endogenous (e.g., sloughed intestinal cells, unresorbed digestive secretions, and microbial debris) and dietary sources. For animals such as large herbivores, that have diets and feces with high concentrations of indigestible fiber, endogenous 15N may constrain the use of fecal δ15N values to estimate dietary δ15N values and reconstruct diets. METHODS: We compared two techniques (detergent and detergent-free) to isolate fractions of plant fibers in the forages of caribou (Rangifer tarandus) and muskoxen (Ovibos moschatus); estimated the discrimination factors between the δ15N values of fecal fiber residues and of the diets of captive animals; and used the more effective isotopic tracer of dietary δ15N values to examine the relationships between the δ15N values of fecal residues and diet composition in several populations of wild caribou and muskoxen throughout North America in winter. RESULTS: The detergent-based approach contaminated the fractions of plant fibers in forages and feces with 14N, whereas the detergent-free method was a good proxy to estimate δ15N values of plant fibers (r2= 0.92) and provided a better estimate of the fecal-fiber to diet discrimination factor for both species (caribou = 3.6‰; muskoxen = 2.8‰). In wild populations, the δ15N values of fecal fibers reflected diet composition in muskoxen (adjusted R2= 0.43) but not caribou (adjusted R2= 0.06). CONCLUSIONS: Contamination from detergent residues prohibited the use of detergent extraction in isolating forage 15N from endogenous 15N in the feces of herbivores. Although δ15N values in fecal fibers can be used to track dietary δ15N values in wild herbivores, discrimination between fecal extracts and diet may vary with the contribution of endogenous nitrogen (N), and, therefore, residual endogenous 15N in feces may limit dietary reconstructions from fecal δ15N values for some large herbivores.

  13. Crystallization, structure and dynamics of the proton-translocating P-type ATPase.

    PubMed

    Scarborough, G A

    2000-01-01

    Large single three-dimensional crystals of the dodecylmaltoside complex of the Neurospora crassa plasma membrane H(+)-ATPase (H(+) P-ATPase) can be grown in polyethylene-glycol-containing solutions optimized for moderate supersaturation of both the protein surfaces and detergent micellar region. Large two-dimensional H(+) P-ATPase crystals also grow on the surface of such mixtures and on carbon films located at such surfaces. Electron crystallographic analysis of the two-dimensional crystals grown on carbon films has recently elucidated the structure of the H(+) P-ATPase at a resolution of 0.8 nm in the membrane plane. The two-dimensional crystals comprise two offset layers of ring-shaped ATPase hexamers with their exocytoplasmic surfaces face to face. Side-to-side interactions between the cytoplasmic regions of the hexamers in each layer can be seen, and an interaction between identical exocytoplasmic loops in opposing hexamer layers holds the two layers together. Detergent rings around the membrane-embedded region of the hexamers are clearly visible, and detergent-detergent interactions between the rings are also apparent. The crystal packing forces thus comprise both protein-protein and detergent-detergent interactions, supporting the validity of the original crystallization strategy. Ten transmembrane helices in each ATPase monomer are well-defined in the structure map. They are all relatively straight, closely packed, moderately tilted at various angles with respect to a plane normal to the membrane surface and average approximately 3.5 nm in length. The transmembrane helix region is connected in at least three places to the larger cytoplasmic region, which comprises several discrete domains separated by relatively wide, deep clefts. Previous work has shown that the H(+) P-ATPase undergoes substantial conformational changes during its catalytic cycle that are not changes in secondary structure. Importantly, the results of hydrogen/deuterium exchange experiments indicate that these conformational changes are probably rigid-body interdomain movements that lead to cleft closure. When interpreted within the framework of established principles of enzyme catalysis, this information on the structure and dynamics of the H(+) P-ATPase molecule provides the basis of a rational model for the sequence of events that occurs as the ATPase proceeds through its transport cycle. The forces that drive the sequence can also be clearly stipulated. However, an understanding of the molecular mechanism of ion transport catalyzed by the H(+) P-ATPase awaits an atomic resolution structure.

  14. Isotopic nitrogen in fecal fiber as an indicator of winter diet in caribou and muskoxen.

    PubMed

    Gustine, David D; Barboza, Perry S; Addison, Jennifer; Shively, Rachel; Oliver, Lola

    2014-03-30

    The ratios of stable nitrogen isotopes (δ(15)N values) in excreta have been used to examine aspects of trophic and nutritional ecology across taxa. Nitrogen fractions in feces of herbivores include endogenous (e.g., sloughed intestinal cells, unresorbed digestive secretions, and microbial debris) and dietary sources. For animals such as large herbivores, that have diets and feces with high concentrations of indigestible fiber, endogenous (15)N may constrain the use of fecal δ(15)N values to estimate dietary δ(15)N values and reconstruct diets. We compared two techniques (detergent and detergent-free) to isolate fractions of plant fibers in the forages of caribou (Rangifer tarandus) and muskoxen (Ovibos moschatus); estimated the discrimination factors between the δ(15)N values of fecal fiber residues and of the diets of captive animals; and used the more effective isotopic tracer of dietary δ(15)N values to examine the relationships between the δ(15)N values of fecal residues and diet composition in several populations of wild caribou and muskoxen throughout North America in winter. The detergent-based approach contaminated the fractions of plant fibers in forages and feces with (14)N, whereas the detergent-free method was a good proxy to estimate δ(15)N values of plant fibers (r(2) = 0.92) and provided a better estimate of the fecal-fiber to diet discrimination factor for both species (caribou = 3.6‰; muskoxen = 2.8‰). In wild populations, the δ(15)N values of fecal fibers reflected diet composition in muskoxen (adjusted R(2) = 0.43) but not caribou (adjusted R(2) = 0.06). Contamination from detergent residues prohibited the use of detergent extraction in isolating forage (15)N from endogenous (15)N in the feces of herbivores. Although δ(15)N values in fecal fibers can be used to track dietary δ(15)N values in wild herbivores, discrimination between fecal extracts and diet may vary with the contribution of endogenous nitrogen (N), and, therefore, residual endogenous (15)N in feces may limit dietary reconstructions from fecal δ(15)N values for some large herbivores. Published in 2014. This article is a US Government work and is in the public domain in the USA.

  15. What contribution do detergent fatty alcohols make to sewage discharges and the marine environment?

    PubMed

    Mudge, Stephen M; Meier-Augenstein, Wolfram; Eadsforth, Charles; DeLeo, Paul

    2010-10-06

    To investigate the potential sources of fatty alcohols arriving at a WWTP and entering the receiving waters, a study was conducted at Treborth North Wales using compound specific stable isotope mass spectrometry (¹³C and ²H). Samples were collected from soils, marine sediments, detergents used in the catchment and in the WWTP. Total fatty alcohol concentrations decreased in the liquid phases through the treatment works with the majority of the compounds accumulating in the sludge (biosolids). Natural plant based detergents have δ¹³C values between -26 and -32‰ while petroleum-based detergents occupy a range between -25 and -30‰. The corresponding δ²H values are -250‰ for natural sourced materials and -50‰ for oil-based detergents which enable these two sources to be separated. The influent to the WWTP contained fatty alcohols which originated mainly from faecal sources and natural surfactants (∼75%) with a smaller amount potentially derived from petroleum-based surfactants (∼25%). The effluents from the WWTP contained mainly short chain compounds with a chain length less than C¹⁶. Their δ²H stable isotope signature was different to the other potential sources examined and suggests bacterial synthesis during the treatment processes. The sludge had relatively high concentrations of fatty alcohols as would be expected from their low water solubility. The stable isotopic signatures were consistent with a mixture of faecal and detergent sources. The sludge in this area is routinely spread on agricultural land as a fertiliser and may find its way back into the sea via land runoff. On the basis of the mean discharge rates and the mean C₁₂ concentration in the effluent, this WWTP would contribute ∼300 g day⁻¹ to the receiving waters. The marine sediment samples had short chain fatty alcohols that are typical of marine production and with stable isotope values that indicate exclusive marine production for the C₁₄ potentially mixed with terrestrial sources for the C₁₆ and C₁₈ compounds. Therefore, the fatty alcohols in the marine sediments are not the same as those that were discharged in the liquid effluent and these fatty alcohols were not the ones that entered the works through the influent but were synthesised or recycled within the works.

  16. Movement and Fate of Solutes in a Plume of Sewage-Contaminated Ground Water, Cape Cod, Massachusetts: U.S. Geological Survey Toxic Waste Ground-Water Contamination Program

    DTIC Science & Technology

    1984-03-01

    contains many inorganic and organic chemicals such as sodium , nitrate, detergents, and volatile organic compounds which can be toxic and render a ground­...1983-- 51 24 . sodium in ground water, 1983---------------------------- 53 25 . chloride in ground water, 1983-------------------------- 54 26...contains elevated concentrations of chloride, sodium , boron, nitrogen, detergents, and other constituents of the treated sewage. The plume was

  17. Protein engineering of subtilisins to improve stability in detergent formulations.

    PubMed

    von der Osten, C; Branner, S; Hastrup, S; Hedegaard, L; Rasmussen, M D; Bisgård-Frantzen, H; Carlsen, S; Mikkelsen, J M

    1993-03-01

    Microbial proteases are used extensively in a large number of industrial processes and most importantly in detergent formulations facilitating the removal of proteinaceous stains. Site-directed mutagenesis has been employed in the construction of subtilisin variants with improved storage and oxidation stabilities. It is shown that in spite of significant structural homology between subtilisins subjected to protein engineering the effects of specific mutations can be quite different. Mutations that stabilize one subtilisin may destabilize another.

  18. Effects of Temperature and Humidity History on Brittleness of α-Sulfonated Fatty Acid Methyl Ester Salt Crystals.

    PubMed

    Watanabe, Hideaki; Morigaki, Atsunori; Kaneko, Yukihiro; Tobori, Norio; Aramaki, Kenji

    2016-01-01

    α-Sulfonated fatty acid methyl ester salts (MES), which were made from vegetable sources, are attractive candidates for eco-friendly washing detergents because they have various special features like excellent detergency, favorable biodegradability, and high stability against enzymes. To overcome some disadvantages of powder-type detergents like caking, sorting, and dusting, we studied how temperature and humidity history, as a model for long-term storage conditions, can affect crystalline structures and reduce the brittleness of MES powder. We characterized the crystalline structure of MES grains using small-angle X-ray scattering, wide-angle X-ray scattering, differential scanning calorimetry, and Fourier transform infrared spectroscopy measurements and determined the yield values, which measure the brittleness of MES grains, in shear stress using dynamic viscoelasticity measurements. This study confirmed that MES crystals form three pseudo-polymorphs via thermal or humidity conditioning: metastable crystals (αsubcell), anhydrous crystals (β subcell), and dihydrate crystals (β' subcell). Further, we found that the yield value increases upon phase transition from the β subcell to the β' subcell and from the β' subcell to the αsubcell. Therefore, controlling the thermal and humidity conditioning of MES grains is an effective way to decrease the brittleness of MES powders and can be used to overcome the above mentioned disadvantages of powder-type detergents in the absence of co-surfactants.

  19. Detergent Induction of HEK 293A Cell Membrane Permeability Measured under Quiescent and Superfusion Conditions Using Whole Cell Patch Clamp

    PubMed Central

    2015-01-01

    Detergents have several biological applications but present cytotoxicity concerns, since they can solubilize cell membranes. Using the IonFlux 16, an ensemble whole cell planar patch clamp, we observed that anionic sodium dodecyl sulfate (SDS), cationic cetyltrimethylammonium bromide (CTAB), and cationic, fluorescent octadecyl rhodamine B (ORB) increased the membrane permeability of cells substantially within a second of exposure, under superfusion conditions. Increased permeability was irreversible for 15 min. At subsolubilizing detergent concentrations, patched cells showed increased membrane currents that reached a steady state and were intact when imaged using fluorescence microscopy. SDS solubilized cells at concentrations of 2 mM (2× CMC), while CTAB did not solubilize cells even at concentrations of 10 mM (1000× CMC). The relative activity for plasma membrane current induction was 1:20:14 for SDS, CTAB, and ORB, respectively. Under quiescent conditions, the relative ratio of lipid to detergent in cell membranes at the onset of membrane permeability was 1:7:5 for SDS, CTAB, and ORB, respectively. The partition constants (K) for SDS, CTAB, and ORB were 23000, 55000, and 39000 M–1, respectively. Combining the whole cell patch clamp data and XTT viability data, SDS ≤ 0.2 mM and CTAB and ORB ≤ 1 mM induced cell membrane permeability without causing acute toxicity. PMID:24548291

  20. Lung gas volumes and expiratory time constant in immature newborn rabbits treated with natural or synthetic surfactant or detergents.

    PubMed

    Bongrani, S; Fornasier, M; Papotti, M; Razzetti, R; Robertson, B

    1994-01-01

    Immature newborn rabbits delivered at a gestational age of 27 days were tracheotomized and treated, via the tracheal cannula, with clinically recommended doses of natural or synthetic surfactant (Curosurf and Exosurf, respectively). Littermates received 0.1% tyloxapol, 5% Tween 20, or saline. The dose volume of Curosurf was 2.5 ml/kg, that of the other materials 5 ml/kg. Animals were kept in a multiplethysmograph system and ventilated for 30 min with a standardized sequence of insufflation pressures. End-expiratory lung gas volume was calculated at the end of the experiment from measurements of lung weight and total lung volume. Tidal volumes were significantly improved in all groups of animals receiving surfactant or detergents. However, expiratory time constant (determined from the tidal volume tracing) was significantly longer, and end-expiratory gas volume significantly larger, in animals treated with Curosurf than in those receiving Exosurf or detergents. These differences were confirmed by semiquantitative evaluation of alveolar air expansion in histological sections. In addition, airway epithelial necrosis was reduced in animals receiving Curosurf, Exosurf, or Tween 20, but not in animals treated with tyloxapol. The discrepancy between improvements in tidal volume, expiratory time constant, and end-expiratory gas volume reflects failure of lung stabilization in animals treated with Exosurf or detergents, probably due to absence of specific hydrophobic proteins in the synthetic products.

  1. DNA Nanotubes for NMR Structure Determination of Membrane Proteins

    PubMed Central

    Bellot, Gaëtan; McClintock, Mark A.; Chou, James J; Shih, William M.

    2013-01-01

    Structure determination of integral membrane proteins by solution NMR represents one of the most important challenges of structural biology. A Residual-Dipolar-Coupling-based refinement approach can be used to solve the structure of membrane proteins up to 40 kDa in size, however, a weak-alignment medium that is detergent-resistant is required. Previously, availability of media suitable for weak alignment of membrane proteins was severely limited. We describe here a protocol for robust, large-scale synthesis of detergent-resistant DNA nanotubes that can be assembled into dilute liquid crystals for application as weak-alignment media in solution NMR structure determination of membrane proteins in detergent micelles. The DNA nanotubes are heterodimers of 400nm-long six-helix bundles each self-assembled from a M13-based p7308 scaffold strand and >170 short oligonucleotide staple strands. Compatibility with proteins bearing considerable positive charge as well as modulation of molecular alignment, towards collection of linearly independent restraints, can be introduced by reducing the negative charge of DNA nanotubes via counter ions and small DNA binding molecules. This detergent-resistant liquid-crystal media offers a number of properties conducive for membrane protein alignment, including high-yield production, thermal stability, buffer compatibility, and structural programmability. Production of sufficient nanotubes for 4–5 NMR experiments can be completed in one week by a single individual. PMID:23518667

  2. Total Protein Extraction for Metaproteomics Analysis of Methane Producing Biofilm: The Effects of Detergents

    PubMed Central

    Huang, Hung-Jen; Chen, Wei-Yu; Wu, Jer-Horng

    2014-01-01

    Protein recovery is crucial for shotgun metaproteomics to study the in situ functionality of microbial populations from complex biofilms but still poorly addressed by far. To fill this knowledge gap, we systematically evaluated the sample preparation with extraction buffers comprising four detergents for the metaproteomics analysis of a terephthalate-degrading methanogenic biofilm using an on-line two-dimensional liquid chromatography tandem mass spectrometry (2D-LC-MS/MS) system. Totally, 1018 non-repeated proteins were identified with the four treatments. On the whole, each treatment could recover the biofilm proteins with specific distributions of molecular weight, hydrophobicity, and isoelectric point. The extraction buffers containing zwitterionic and anionic detergents were found to harvest the proteins with better efficiency and quality, allowing identification up to 76.2% of total identified proteins with the LC-MS/MS analysis. According to the annotation with a relevant metagenomic database, we further observed different taxonomic profiles of bacterial and archaeal members and discriminable patterns of the functional expression among the extraction buffers used. Overall, the finding of the present study provides first insight to the effect of the detergents on the characteristics of extractable proteins from biofilm and the developed protocol combined with nano 2D-LC/MS/MS analysis can improve the metaproteomics studies on microbial functionality of biofilms in the wastewater treatment systems. PMID:24914765

  3. Cow dung: a potential biomass substrate for the production of detergent-stable dehairing protease by alkaliphilic Bacillus subtilis strain VV.

    PubMed

    Vijayaraghavan, Ponnuswamy; Vijayan, Aija; Arun, Arumugaperumal; Jenisha, John Kennady; Vincent, Samuel Gnana Prakash

    2012-01-01

    Cow dung, a cheap and easily available source of energy, was used as the substrate for the production of alkaline protease by solid-state fermentation using the Bacillus subtilis strain VV. In order to achieve the maximum yield of this enzyme, the following optimum process parameters are needed: fermentation period (72 h), pH (10.0), moisture content (140%), inoculum (25%), temperature (30-40°C), carbon source (2% (w/w) maltose) and nitrogen source (1% (w/w) urea). The protease was stable over a broad temperature range (30-50°C) and pH (8.0-10.0), with maximum activity at 50°C and pH 10.0. Among the divalent ions tested, Ca(2+) (0.01 M) increased enzyme activity. The purified protease, after being subjected to sodium dodecyl sulphate-polyacrylamide gel electrophoresis, was found to have a molecular mass of 38.5 kDa. The enzyme was solvent-and surfactant-stable and showed activity even after 24 h incubation along with various commercially available detergents. This enzyme possessed dehairing properties for animal hide after 16 h of incubation at room temperature. From these results it is evident that cow dung is a potential substrate for the production of a detergent-stable, dehairing protease by B. subtilis. This enzyme has a lot of potential applications in the detergent and leather-processing industries.

  4. Robustness of solvent/detergent treatment of plasma derivatives: a data collection from Plasma Protein Therapeutics Association member companies.

    PubMed

    Dichtelmüller, Herbert O; Biesert, Lothar; Fabbrizzi, Fabrizio; Gajardo, Rodrigo; Gröner, Albrecht; von Hoegen, Ilka; Jorquera, Juan I; Kempf, Christoph; Kreil, Thomas R; Pifat, Dominique; Osheroff, Wendy; Poelsler, Gerhard

    2009-09-01

    Solvent/detergent (S/D) treatment is an established virus inactivation technology that has been applied in the manufacture of medicinal products derived from human plasma for more than 20 years. Data on the inactivation of enveloped viruses by S/D treatment collected from seven Plasma Protein Therapeutics Association member companies demonstrate the robustness, reliability, and efficacy of this virus inactivation method. The results from 308 studies reflecting production conditions as well as technical variables significantly beyond the product release specification were evaluated for virus inactivation, comprising different combinations of solvent and detergent (tri(n-butyl) phosphate [TNBP]/Tween 80, TNBP/Triton X-100, TNBP/Na-cholate) and different products (Factor [F]VIII, F IX, and intravenous and intramuscular immunoglobulins). Neither product class, process temperature, protein concentration, nor pH value has a significant impact on virus inactivation. A variable that did appear to be critical was the concentration of solvent and detergent. The data presented here demonstrate the robustness of virus inactivation by S/D treatment for a broad spectrum of enveloped test viruses and process variables. Our data substantiate the fact that no transmission of viruses such as human immunodeficiency virus, hepatitis B virus, hepatitis C virus, or of other enveloped viruses was reported for licensed plasma derivatives since the introduction of S/D treatment.

  5. Inactivation of virus in intravenous immunoglobulin G using solvent/detergent treatment and pasteurization.

    PubMed

    Aghaie, A; Pourfatollah, A A; Bathaie, S Z; Moazzeni, S M; Khorsand Mohammad Pour, H; Sharifi, Z

    2008-01-01

    The safety of plasma derived medicinal products, such as immunoglobulin, depends on viral inactivation steps that are incorporated into the production process. Several attempts have been made to validate the effectiveness of these inactivation methods against a range of physio-chemically diverse viruses. Treatment with solvent/detergent (S/D) and pasteurization (P) has been continuously used in our IgG production and these methods were analysed in this study as models of viral inactivation. Bovine Viral Diarrhoea Virus (BVDV), Herpes Simplex Virus (HSV) and Vesicular Stomatitis Virus (VSV) were employed as models of HCV, HBV and HIV respectively. Polio and Reo viruses also were used as stable viruses to chemical substances. The infectivity of a range of viruses before and after treatment with two methods of viral inactivation was measured by end point titration and their effectiveness expressed as Logarithmic Reduction Factors (LRF). Solvent/detergent treatment reduced the amount of enveloped viruses by 5-6 logs. The reduction factor was between 5-6 logs for all viruses used in the pasteurization process. A final log reduction factor was obtained as the sum of the two individual methods. Both inactivation methods have advantages and disadvantages with respect to their ability to inactivate viruses. Thus,combination of two robust virus inactivation steps, solvent/detergent and pasteurization, increases the safety margin of immunoglobulin preparations.

  6. Comparative antibacterial activity of hexachlorophane in different formulations used for skin disinfection

    PubMed Central

    Gibson, J. W.

    1969-01-01

    Two formulations of hexachlorophane have been compared for their antibacterial effects in respect of skin disinfection. It was found that the activity of hexachlorophane is dependent upon its vehicle of formulation. A 2·5% soap gel possesses broad-spectrum bactericidal activity with remarkable speed of kill, whereas a 3% detergent formulation has no bactericidal action against Gram-negative bacteria and only a very slow action against Gram-positive bacteria. In practice the rapid action of the 2·5% soap gel against both Gram-negative and Gram-positive transient skin bacteria can be achieved by correctly applying the preparation directly to the dry hands. It appears that the 2·5% soap gel does not need to rely on mechanical removal of transient organisms as does the 3% detergent. The 2·5% soap gel is more dependable in its action on the resident bacteria than the 3% detergent. It controlled the resident flora in the skin of all subjects tested whereas the latter appeared to be potentiated on the skin of certain individuals only. It has been possible to distinguish between the antibacterial effect on the resident organisms and the mere removal of transient bacteria by mechanical action of the 3% detergent as opposed to antibacterial effect on residents and rapid antibacterial effect on transients by the 2·5% soap gel. PMID:5784696

  7. Restricting detergent protease action to surface of protein fibres by chemical modification.

    PubMed

    Schroeder, M; Lenting, H B M; Kandelbauer, A; Silva, C J S M; Cavaco-Paulo, A; Gübitz, G M

    2006-10-01

    Due to their excellent properties, such as thermostability, activity over a broad range of pH and efficient stain removal, proteases from Bacillus sp. are commonly used in the textile industry including industrial processes and laundry and represent one of the most important groups of enzymes. However, due to the action of proteases, severe damage on natural protein fibres such as silk and wool result after washing with detergents containing proteases. To include the benefits of proteases in a wool fibre friendly detergent formulation, the soluble polymer polyethylene glycol (PEG) was covalently attached to a protease from Bacillus licheniformis. In contrast to activation of PEG with cyanuric chloride (50%) activation with 1,1'-carbonyldiimidazole (CDI) lead to activity recovery above 90%. With these modified enzymes, hydrolytic attack on wool fibres could be successfully prevented up to 95% compared to the native enzymes. Colour difference (DeltaE) measured in the three dimensional colour space showed good stain removal properties for the modified enzymes. Furthermore, half-life of the modified enzymes in buffers and commercial detergents solutions was nearly twice as high as those of the non-modified enzymes with values of up to 63 min. Out of the different modified proteases especially the B. licheniformis protease with the 2.0-kDa polymer attached both retained stain removal properties and did not hydrolyse/damage wool fibres.

  8. The Speciation of Silver Nanoparticles in Antimicrobial Fabric Before and After Exposure to a Hypochlorite/Detergent Solution

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Impellitteri, Christopher A.; Tolaymat, Thabet M.; Scheckel, Kirk G.

    2009-07-14

    Because of their antibacterial properties, silver nanoparticles are often used in consumer products. To assess environmental and/or human health risks from these nanoparticles, there is a need to identify the chemical transformations that silver nanoparticles undergo in different environments. Thus an antimicrobial sock material containing Ag nanoparticles was examined by X-ray absorption spectroscopy to identify the speciation of Ag. The material was exposed to a hypochlorite/detergent solution and subjected to agitation. An elemental Ag nanopowder was also exposed to the hypochlorite/detergent solution or to a 1 mol L{sup -1} NaCl solution. Results showed that the sock material nanoparticles consisted ofmore » elemental Ag. After exposure to the hypochlorite/detergent solution, a significant portion (more than 50%) of the sock nanoparticles were converted, in situ, to AgCl. Results from exposures to elemental Ag nanopowder suggest that an oxidation step is necessary for the elemental Ag nanoparticles to transform into AgCl as there was no evidence of AgCl formation in the presence of chloride alone. As a result, if Ag ions leach from consumer products, any chloride present may quickly scavenge the ions. In addition, the efficacy of Ag, as an antimicrobial agent in fabrics, may be limited, or even negated, after washing in solutions containing oxidizers as AgCl is much less reactive than Ag ion.« less

  9. Improved catalytic efficiency, thermophilicity, anti-salt and detergent tolerance of keratinase KerSMD by partially truncation of PPC domain

    PubMed Central

    Fang, Zhen; Zhang, Juan; Du, Guocheng; Chen, Jian

    2016-01-01

    The keratinase from Stenotrophomonas maltophilia (KerSMD) is known for its high activity and pH stability in keratin degradation. However, catalytic efficiency and detergent tolerability need to be improved in order to be used for industrial application. In this work, we obtained several keratinase variants with enhanced catalytic efficiency, thermophilicity, and anti-salt and detergent tolerability by partially truncating the PPC domain of KerSMD. The variants all showed improved catalytic efficiency to synthetic substrate AAPF, with the V355 variant having the highest kcat /Km value of 143.6 s−1 mM−1. The truncation of keratinase had little effect on alkaline stability but obviously decreased collagenase activity, developing its potential application in leather treatment. The variants V380, V370, and V355 were thermophilic, with a 1.7-fold enhancement of keratinlytic activity at 60 °C when compared to the wild type. The entire truncation of PPC domain obtained the variant V355 with improved tolerance to alkalinity, salt, chaotropic agents, and detergents. The V355 variant showed more than a 40% improvement in activity under 15% (w/v) NaCl or 4% (w/v) SDS solution, showing excellent stability under harsh washing and unhairing conditions. Our work investigated how protein engineering affects the function of PPC domain of KerSMD. PMID:27298079

  10. Improved catalytic efficiency, thermophilicity, anti-salt and detergent tolerance of keratinase KerSMD by partially truncation of PPC domain.

    PubMed

    Fang, Zhen; Zhang, Juan; Du, Guocheng; Chen, Jian

    2016-06-14

    The keratinase from Stenotrophomonas maltophilia (KerSMD) is known for its high activity and pH stability in keratin degradation. However, catalytic efficiency and detergent tolerability need to be improved in order to be used for industrial application. In this work, we obtained several keratinase variants with enhanced catalytic efficiency, thermophilicity, and anti-salt and detergent tolerability by partially truncating the PPC domain of KerSMD. The variants all showed improved catalytic efficiency to synthetic substrate AAPF, with the V355 variant having the highest kcat /Km value of 143.6 s(-1) mM(-1). The truncation of keratinase had little effect on alkaline stability but obviously decreased collagenase activity, developing its potential application in leather treatment. The variants V380, V370, and V355 were thermophilic, with a 1.7-fold enhancement of keratinlytic activity at 60 °C when compared to the wild type. The entire truncation of PPC domain obtained the variant V355 with improved tolerance to alkalinity, salt, chaotropic agents, and detergents. The V355 variant showed more than a 40% improvement in activity under 15% (w/v) NaCl or 4% (w/v) SDS solution, showing excellent stability under harsh washing and unhairing conditions. Our work investigated how protein engineering affects the function of PPC domain of KerSMD.

  11. Enzymatic activity of a subtilisin homolog, Tk-SP, from Thermococcus kodakarensis in detergents and its ability to degrade the abnormal prion protein

    PubMed Central

    2013-01-01

    Background Tk-SP is a member of subtilisin-like serine proteases from a hyperthermophilic archaeon Thermococcus kodakarensis. It has been known that the hyper-stable protease, Tk-SP, could exhibit enzymatic activity even at high temperature and in the presence of chemical denaturants. In this work, the enzymatic activity of Tk-SP was measured in the presence of detergents and EDTA. In addition, we focused to demonstrate that Tk-SP could degrade the abnormal prion protein (PrPSc), a protease-resistant isoform of normal prion protein (PrPC). Results Tk-SP was observed to maintain its proteolytic activity with nonionic surfactants and EDTA at 80°C. We optimized the condition in which Tk-SP functions efficiently, and demonstrated that the enzyme is highly stable in the presence of 0.05% (w/v) nonionic surfactants and 0.01% (w/v) EDTA, retaining up to 80% of its activity. Additionally, we also found that Tk-SP can degrade PrPSc to a level undetectable by western-blot analysis. Conclusions Our results indicate that Tk-SP has a great potential for technological applications, such as thermo-stable detergent additives. In addition, it is also suggested that Tk-SP-containing detergents can be developed to decrease the secondary infection risks of transmissible spongiform encephalopathies (TSE). PMID:23448268

  12. DNA nanotubes for NMR structure determination of membrane proteins.

    PubMed

    Bellot, Gaëtan; McClintock, Mark A; Chou, James J; Shih, William M

    2013-04-01

    Finding a way to determine the structures of integral membrane proteins using solution nuclear magnetic resonance (NMR) spectroscopy has proved to be challenging. A residual-dipolar-coupling-based refinement approach can be used to resolve the structure of membrane proteins up to 40 kDa in size, but to do this you need a weak-alignment medium that is detergent-resistant and it has thus far been difficult to obtain such a medium suitable for weak alignment of membrane proteins. We describe here a protocol for robust, large-scale synthesis of detergent-resistant DNA nanotubes that can be assembled into dilute liquid crystals for application as weak-alignment media in solution NMR structure determination of membrane proteins in detergent micelles. The DNA nanotubes are heterodimers of 400-nm-long six-helix bundles, each self-assembled from a M13-based p7308 scaffold strand and >170 short oligonucleotide staple strands. Compatibility with proteins bearing considerable positive charge as well as modulation of molecular alignment, toward collection of linearly independent restraints, can be introduced by reducing the negative charge of DNA nanotubes using counter ions and small DNA-binding molecules. This detergent-resistant liquid-crystal medium offers a number of properties conducive for membrane protein alignment, including high-yield production, thermal stability, buffer compatibility and structural programmability. Production of sufficient nanotubes for four or five NMR experiments can be completed in 1 week by a single individual.

  13. Quality analysis, miceller behavior, and environmental impact of some laundry detergents available in Bangladesh.

    PubMed

    Nur-E-Alam, M; Islam, M Monirul; Islam, M Nazrul; Rima, Farhana Rahman; Islam, M Nurul

    2016-03-01

    The cleansing efficiencies of laundry detergents depend on composition and variation of ingredients such as surfactants, phosphate, and co-builders. Among these ingredients, surfactants and phosphate are considered as hazardous materials. Knowledge on compositions and micellar behavior is very useful for understanding their cleansing efficiencies and environmental impact. With this view, composition, critical micelle concentration, and dissolved oxygen level in aqueous solution of some laundry detergents available in Bangladesh such as keya, Wheel Power White, Tibet, Surf Excel, and Chaka were determined. Surfactant and phosphate were found to be maximum in Surf Excel and Wheel Power White, respectively, while both of the ingredients were found to be minimum in Tibet. The critical micelle concentration decreased with increasing surfactant content. The amount of laundry detergents required for efficient cleansing was found to be minimum for Surf Excel and maximum for Chaka; however, cleansing cost was the highest for Surf Excel and the lowest for Tibet. The maximum amount of surfactants and phosphate was discharged by Surf Excel and Wheel Power White, respectively, while discharges of both of the ingredients were minimum for Tibet. The maximum decrease of dissolved oxygen level was caused by Surf Excel and the minimum by Tibet. Therefore, it can be concluded that Tibet is cost-effective and environment friendly, whereas Surf Excel and Wheel Power White are expensive and pose a threat to water environment.

  14. n-Dodecyl β-D-maltoside specifically competes with general anesthetics for anesthetic binding sites.

    PubMed

    Xu, Longhe; Matsunaga, Felipe; Xi, Jin; Li, Min; Ma, Jingyuan; Liu, Renyu

    2014-01-01

    We recently demonstrated that the anionic detergent sodium dodecyl sulfate (SDS) specifically interacts with the anesthetic binding site in horse spleen apoferritin, a soluble protein which models anesthetic binding sites in receptors. This raises the possibility of other detergents similarly interacting with and occluding such sites from anesthetics, thereby preventing the proper identification of novel anesthetic binding sites. n-Dodecyl β-D-maltoside (DDM) is a non-ionic detergent commonly used during protein-anesthetic studies because of its mild and non-denaturing properties. In this study, we demonstrate that SDS and DDM occupy anesthetic binding sites in the model proteins human serum albumin (HSA) and horse spleen apoferritin and thereby inhibit the binding of the general anesthetics propofol and isoflurane. DDM specifically interacts with HSA (Kd = 40 μM) with a lower affinity than SDS (Kd = 2 μM). DDM exerts all these effects while not perturbing the native structures of either model protein. Computational calculations corroborated the experimental results by demonstrating that the binding sites for DDM and both anesthetics on the model proteins overlapped. Collectively, our results indicate that DDM and SDS specifically interact with anesthetic binding sites and may thus prevent the identification of novel anesthetic sites. Special precaution should be taken when undertaking and interpreting results from protein-anesthetic investigations utilizing detergents like SDS and DDM.

  15. S. aureus MscL is a pentamer in vivo but of variable stoichiometries in vitro: implications for detergent-solubilized membrane proteins.

    PubMed

    Dorwart, Michael R; Wray, Robin; Brautigam, Chad A; Jiang, Youxing; Blount, Paul

    2010-12-07

    While the bacterial mechanosensitive channel of large conductance (MscL) is the best studied biological mechanosensor and serves as a paradigm for how a protein can sense and respond to membrane tension, the simple matter of its oligomeric state has led to debate, with models ranging from tetramers to hexamers. Indeed, two different oligomeric states of the bacterial mechanosensitive channel MscL have been resolved by X-ray crystallography: The M. tuberculosis channel (MtMscL) is a pentamer, while the S. aureus protein (SaMscL) forms a tetramer. Because several studies suggest that, like MtMscL, the E. coli MscL (EcoMscL) is a pentamer, we re-investigated the oligomeric state of SaMscL. To determine the structural organization of MscL in the cell membrane we developed a disulfide-trapping approach. Surprisingly, we found that virtually all SaMscL channels in vivo are pentameric, indicating this as the physiologically relevant and functional oligomeric state. Complementing our in vivo results, we purified SaMscL and assessed its oligomeric state using three independent approaches (sedimentation equilibrium centrifugation, crosslinking, and light scattering) and established that SaMscL is a pentamer when solubilized in Triton X-100 and C(8)E(5) detergents. However, performing similar experiments on SaMscL solubilized in LDAO, the detergent used in the crystallographic study, confirmed the tetrameric oligomerization resolved by X-ray crystallography. We further demonstrate that this stoichiometric shift is reversible by conventional detergent exchange experiments. Our results firmly establish the pentameric organization of SaMscL in vivo. Furthermore they demonstrate that detergents can alter the subunit stoichiometry of membrane protein complexes in vitro; thus, in vivo assays are necessary to firmly establish a membrane protein's true functionally relevant oligomeric state.

  16. The electrochemical-proton-gradient-activated states of F0F1 ATPase in plant mitochondria as revealed by detergents.

    PubMed

    Valerio, M; Diolez, P; Haraux, F

    1993-09-01

    ATP hydrolysis, triggered by the addition of polyoxyethylene-9-lauryl ether (Lubrol) or lauryldimethylamine oxide (LDAO) to energized plant mitochondria was studied in some details. The membrane disruption was quasi-instantaneous (2-3 s) with both detergents, as shown by the decrease of turbidity and the stopping of respiration. In pea leaf mitochondria, Lubrol triggered ATP hydrolysis in almost the same way as valinomycin plus nigericin, except that the activity was slightly stimulated and became insensitive to carboxyatractyloside. This allowed investigations of ATP hydrolysis without any interference of the ATP/ADP antiporter or the phosphate carrier. Lubrol did not prevent the ATPase from deactivating in pea leaf mitochondria, and did not trigger any ATP hydrolysis in potato tuber mitochondria. At variance with Lubrol, LDAO changed the properties of the F0F1 ATPase. It made the enzyme oligomycin insensitive and froze it in an activated state. The activity was also 5-8-times stimulated in pea leaf mitochondria. Moreover, LDAO revealed an important ATP hydrolase activity when added to energized potato tuber mitochondria. Despite the specific effect of LDAO, the activity triggered by this detergent strongly depended on the energized state of the organelles before detergent addition. From this study, it is concluded that the electrochemical proton gradient is completely necessary to activate the F0F1-ATPase in intact plant mitochondria, as known in chloroplasts and suggested by some reports in animal mitochondria. Moreover, it is suggested that the main difference between the enzymes of pea leaf and potato tuber mitochondria is their rate of deactivation after the collapse of the transmembrane electrochemical potential difference. Finally, when properly used, detergents appear to be a powerful tool to probe the state of the ATPase in intact mitochondria, and maybe in more integrated systems.

  17. Intestinal receptor for heat-stable enterotoxin of Escherichia coli is tightly coupled to a novel form of particulate guanylate cyclase.

    PubMed Central

    Waldman, S A; Kuno, T; Kamisaki, Y; Chang, L Y; Gariepy, J; O'Hanley, P; Schoolnik, G; Murad, F

    1986-01-01

    A novel form of particulate guanylate cyclase tightly coupled by cytoskeletal components to receptors for heat-stable enterotoxin (ST) produced by Escherichia coli can be found in membranes from rat intestinal mucosa. Intestinal particulate guanylate cyclase was resistant to solubilization with detergent alone, with only 30% of the total enzyme activity being extracted with Lubrol-PX. Under similar conditions, 70% of this enzyme was solubilized from rat lung membranes. The addition of high concentrations of sodium chloride to the extraction buffer resulted in greater solubilization of particulate guanylate cyclase from intestinal membranes. Although extraction of intestinal membranes with detergent and salt resulted in greater solubilization of guanylate cyclase, a small fraction of the enzyme activity remained associated with the particulate fraction. This activity was completely resistant to solubilization with a variety of detergents and chaotropes. Particulate guanylate cyclase and the ST receptor solubilized by detergent retained their abilities to produce cyclic GMP and bind ST, respectively. However, ST failed to activate particulate guanylate cyclase in detergent extracts. In contrast, guanylate cyclase resistant to solubilization remained functional and coupled to the ST receptor since enzyme activation by ST was unaffected by various extraction procedures. The possibility that the ST receptor and particulate guanylate cyclase were the same molecule was explored. ST binding and cyclic GMP production were separated by affinity chromatography on GTP-agarose. Similarly, guanylate cyclase migrated as a 300,000-dalton protein, while the ST receptor migrated as a 240,000-dalton protein on gel filtration chromatography. Also, thiol-reactive agents such as cystamine and N-ethylmaleimide inhibited guanylate cyclase activation by ST, with no effect on receptor binding of ST. These data suggest that guanylate cyclase and the ST receptor are independent proteins coupled by cytoskeletal components in membranes of intestinal mucosa. PMID:2867046

  18. Biochemical process of low level radioactive liquid simulation waste containing detergent

    NASA Astrophysics Data System (ADS)

    Kundari, Noor Anis; Putra, Sugili; Mukaromah, Umi

    2015-12-01

    Research of biochemical process of low level radioactive liquid waste containing detergent has been done. Thse organic liquid wastes are generated in nuclear facilities such as from laundry. The wastes that are cotegorized as hazard and poison materials are also radioactive. It must be treated properly by detoxification of the hazard and decontamination of the radionuclides to ensure that the disposal of the waste meets the requirement of standard quality of water. This research was intended to determine decontamination factor and separation efficiensies, its kinetics law, and to produce a supernatant that ensured the environmental quality standard. The radioactive element in the waste was thorium with activity of 5.10-5 Ci/m3. The radioactive liquid waste which were generated in simulation plant contains detergents that was further processed by aerobic biochemical process using SGB 103 bacteria in a batch reactor equipped with aerators. Two different concentration of samples were processed and analyzed for 212 hours and 183 hours respectively at a room temperature. The product of this process is a liquid phase called as supernatant and solid phase material called sludge. The chemical oxygen demand (COD), biological oxygen demand (BOD), suspended solid (SS), and its alpha activity were analyzed. The results show that the decontamination factor and the separation efficiency of the lower concentration samples are higher compared to the samples with high concentration. Regarding the decontamination factor, the result for 212 hours processing of waste with detergent concentration of 1.496 g/L was 3.496 times, whereas at the detergent concentration of 0.748 g/L was 15.305 times for 183 hours processing. In case of the separation efficiency, the results for both samples were 71.396% and 93.465% respectively. The Bacterial growth kinetics equation follow Monod's model and the decreasing of COD and BOD were first order with the rate constant of 0.01 hour-1.

  19. Biochemical process of low level radioactive liquid simulation waste containing detergent

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kundari, Noor Anis, E-mail: nooranis@batan.go.id; Putra, Sugili; Mukaromah, Umi

    Research of biochemical process of low level radioactive liquid waste containing detergent has been done. Thse organic liquid wastes are generated in nuclear facilities such as from laundry. The wastes that are cotegorized as hazard and poison materials are also radioactive. It must be treated properly by detoxification of the hazard and decontamination of the radionuclides to ensure that the disposal of the waste meets the requirement of standard quality of water. This research was intended to determine decontamination factor and separation efficiensies, its kinetics law, and to produce a supernatant that ensured the environmental quality standard. The radioactive elementmore » in the waste was thorium with activity of 5.10{sup −5} Ci/m{sup 3}. The radioactive liquid waste which were generated in simulation plant contains detergents that was further processed by aerobic biochemical process using SGB 103 bacteria in a batch reactor equipped with aerators. Two different concentration of samples were processed and analyzed for 212 hours and 183 hours respectively at a room temperature. The product of this process is a liquid phase called as supernatant and solid phase material called sludge. The chemical oxygen demand (COD), biological oxygen demand (BOD), suspended solid (SS), and its alpha activity were analyzed. The results show that the decontamination factor and the separation efficiency of the lower concentration samples are higher compared to the samples with high concentration. Regarding the decontamination factor, the result for 212 hours processing of waste with detergent concentration of 1.496 g/L was 3.496 times, whereas at the detergent concentration of 0.748 g/L was 15.305 times for 183 hours processing. In case of the separation efficiency, the results for both samples were 71.396% and 93.465% respectively. The Bacterial growth kinetics equation follow Monod’s model and the decreasing of COD and BOD were first order with the rate constant of 0.01 hour{sup −1}.« less

  20. Hunting for huntingtin associated factors: Identification and characterization of huntingtin expanded polyglutamine aggregate associated factors and their impact on Huntington disease model cellular toxicity

    DTIC Science & Technology

    2016-05-20

    ID) domains. ... 21 Figure 6: Western blotting confirms that TAPI-identified proteins are trapped in large, detergent- resistant Htt-polyQ...aggregates stained with iodine, which is used to detect starch ; hence they were named ‘amyloid,’ or ‘ starch -like’ (18; 187). Since that time, great...β-rich structure of amyloid that results in strong resistance to degradation, detergents, proteolysis, and mechanical breakage (49). Amyloid

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