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1.
Microb Cell Fact ; 18(1): 37, 2019 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-30777089

RESUMO

Upon publication of this article [1], the authors realized that one of the coauthor name was accedentally deleted during the review process and not presented in the original version of the article. The coauthor Dr. Ram Prasad should be listed as fifth author. The corrected author group is published with this erratum.

2.
Microb Cell Fact ; 17(1): 182, 2018 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-30454058

RESUMO

BACKGROUND: Vegetable 'mandi' (road-side vegetable market) waste was converted to a suitable fermentation medium for cultivation of oleaginous yeast Rhodosporidium toruloides by steaming under pressure. This cultivation medium derived from waste was found to be a comparatively better source of nutrients than standard culture media because it provided more than one type of usable carbon source(s) to yeast. RESULTS: HPLC results showed that the extract contained glucose, xylose and glycerol along with other carbon sources, allowing triauxic growth pattern with preferably usage of glucose, xylose and glycerol resulting in enhanced growth, lipid and carotenoid production. Presence of saturated and unsaturated fatty acid methyl esters (FAMEs) (C14-20) in the lipid profile showed that the lipid may be transesterified for biodiesel production. CONCLUSION: Upscaling these experiments to fermenter scale for the production of lipids and biodiesel and other industrially useful products would lead to waste management along with the production of value added commodities. The technique is thus environment friendly and gives good return upon investment.


Assuntos
Lipídeos/biossíntese , Resíduos , Leveduras/crescimento & desenvolvimento , Leveduras/metabolismo , beta Caroteno/biossíntese , Glucose/metabolismo , Cinética
3.
Parasitol Res ; 111(1): 383-92, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22395660

RESUMO

A total of 116 samples (44 clinical specimens and 72 environmental samples) have been analyzed for the presence of Acanthamoeba. The environmental samples (ESs) were collected from four drinking water treatment plants (DWTP, n=32), seven wastewater treatment plants (n=28), and six locations of influence (n=12) on four river basins from the central area of Spain (winter-spring 2008). Water samples were concentrated by using the IDEXX Filta-Max(®) system. Acanthamoeba was identified in 65 of the 72 ESs by culture isolation (90.3%) and 63 by real-time PCR (87.5%), resulting in all sampling points (100%) positive for Acanthamoeba when considering both techniques and all the time period analyzed. Nine of the 44 clinical specimens were positive for Acanthamoeba. Seventeen Acanthamoeba strains (eight from four DWTP and nine from clinical samples) were also established in axenic-PYG medium. Twenty-four of the ESs and the 17 Acanthamoeba sp. strains were genotyped as T4/1, T4/8, and T4/9. The eight strains isolated from the DWTP samples were inoculated in nude mouse to ascertain their potential pathogenicity in this model. Animals that were inoculated died or showed central nervous system symptoms 9 days post-inoculation. Examination of immunofluorescence-stained brain and lung tissue sections showed multiple organisms invading both tissues, and re-isolation of throphozoites was successful in these tissues of all infected animals. For the first time, potentially pathogenic Acanthamoeba T4 has been detected in 100% of different types of water samples including tap water and sewage effluents in the central area of Spain suggesting a potential health threat for humans especially for the contact lens wearers.


Assuntos
Acanthamoeba/classificação , Acanthamoeba/isolamento & purificação , Amebíase/parasitologia , Água/parasitologia , Acanthamoeba/genética , Amebíase/mortalidade , Amebíase/patologia , Animais , Encéfalo/parasitologia , Encéfalo/patologia , DNA de Protozoário/genética , Genótipo , Humanos , Pulmão/parasitologia , Pulmão/patologia , Camundongos , Camundongos Nus , Reação em Cadeia da Polimerase em Tempo Real , Espanha , Análise de Sobrevida , Purificação da Água
4.
Environ Technol ; : 1-16, 2022 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-36045480

RESUMO

Tropical soils are often deeply weathered and vulnerable to degradation having low pH and unfavorable Al/Fe levels, which can constrain crop production. This study aims to examine nitrogen-enriched novel biochar co-composts prepared from rice straw, maize stover, and gram residue in various mixing ratios of the biochar and their feedstock materials for the amelioration of acidic tropical soil. Three pristine biochar and six co-composts were prepared, characterized, and evaluated for improving the chemical and biological quality of the soil against a conventional lime treatment. The pH, cation exchange capacity (CEC), calcium carbonate equivalence (CCE) and nitrogen content of co-composts varied between 7.78-8.86, 25.3-30.5 cmol (p+) kg-1, 25.5-30.5%, and 0.81-1.05%, respectively. The co-compost prepared from gram residue biochar mixed with maize stover at a 1:7 dry-weight ratio showed the highest rise in soil pH and CEC, giving an identical performance with the lime treatment and significantly better effect (p < .05) than the unamended control. Agglomerates of calcite and dolomite in biochar co-composts, and surface functional groups contributed to pH neutralization and increased CEC of the amended soil. The co-composts also significantly (p < .05) increased the dehydrogenase (1.87 µg TPF g-1 soil h-1), ß-glucosidase (90 µg PNP g-1 soil h-1), and leucine amino peptidase (3.22 µmol MUC g-1 soil h-1) enzyme activities in the soil, thereby improving the soil's biological quality. The results of this study are encouraging for small-scale farmers in tropical developing countries to sustainably reutilize crop residues via biochar-based co-composting technology.

5.
3 Biotech ; 8(10): 434, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30306003

RESUMO

This study investigated the potential of oleaginous yeast Rhodosporidium toruloides strain (ATCC20409) for the sustainable production of microbial lipids as biodiesel feedstock and other economically important fatty acids in comparison to algal or plant-based biodiesel. The strain exhibited high lipid content (76% of dry cell weight biomass) through consolidated bioprocessing which was transesterified to produce biodiesel. Physico-chemical properties of the biodiesel produced showed that they were in accordance with ASTM standards, although few parameters such as acid value, calorific value and free fatty acid value differed to some extent, as also reported in plant-based/microalgal biodiesel. Fatty acid methyl esters analysis of biodiesel showed 50.18% unsaturated fatty acid and 49.81% saturated fatty acid. Total content of (monounsaturated fatty acid) MUFA was higher than (polyunsaturated fatty acid) PUFA, being 44.36% and 2.69%, respectively. Considering the yield and cost, lipid extracted from R. toruloides may become a promising alternative feed in biodiesel production.

6.
Indian J Plant Physiol ; 23(3): 416-425, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30416202

RESUMO

Field experiments were conducted to study the effect of irrigation and nitrogen levels on radiation use efficiency (RUE), radiation extinction coefficient (κ) and temporal variation of leaf area index (LAI) and fraction intercepted photosynthetically active radiation (fIPAR). The LAI of wheat increased with increase in irrigation and nitrogen levels. The fIPAR also followed trend similar to LAI. The LAI and fIPAR showed logarithmic relationship with R2 value of 0.92 and 0.93 for the years 2013-2014 and 2014-2015, respectively. The κ value varied between 0.41 and 0.78 and was significantly affected by nitrogen levels but was not influenced by irrigation levels. The grain and above ground biomass (AGB) yields of wheat were not affected significantly by irrigation levels. However, application of 160 kg N ha-1 (N160) registered higher grain (12-33%) and AGB (22-25%) yeilds as compared to that with application of 40 kg N ha-1 (N40). Similar to AGB, the total intercepted photosynthetically active radiation (TIPAR) was not affected by irrigation levels but N160 treatment registered 9-20% higher TIPAR compared to N40 treatment. The linear relationship between TIPAR and AGB revealed that 83-86% variation in AGB yield of wheat can be explained by TIfIPAR. The RUE of wheat under three irrigations (I3) was 6 and 18% higher (P < 0.05) than the five (I5) and two (I2) irrigation treatments, respectively for the year 2013-2014. However, there was no significant effect of irrigation on RUE of wheat in the year 2014-2015. N160 treatment registered 5-13% higher RUE than the N40 treatment. Thus wheat may be grown with three irrigations (CRI, flowering and grain filling) and 160 kg N ha-1 for higher RUE without significant reduction in AGB of wheat compared to five irrigation levels in semi-arid location of Delhi region.

7.
Bioresour Technol ; 97(16): 2182-8, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16289791

RESUMO

A field experiment was conducted on a Vertisol for three consecutive years (1998-2000) to study the effects of combined use of inorganic fertilizer (NPK) and organic manure (farmyard manure) on soil physical properties, water-use efficiency, root growth and yield of soybean [Glycine max (L.) Merr.] in a soybean-mustard cropping system. Application of 10 Mg farmyard manure and recommended NPK (NPK+FYM) to soybean for three consecutive years improved the organic carbon content of the surface (0-15 cm) soil from an initial value of 4.4 g kg(-1) to 6.2 g kg(-1) and also increased seed yield and water-use efficiency by 103% and 76%, respectively, over the control. The surface (0-15 cm) soil of the plots receiving both farmyard manure and recommended NPK had larger mean weight diameter (0.50 mm) and a higher percentage of water stable aggregates (55%) than both the inorganically fertilized (NPK) (0.44 mm and 49%) and unfertilized control plots (0.41 mm and 45.4%). The saturated hydraulic conductivity (13.32 x 10(-6) m s(-1)) of the NPK+FYM treatment of the 0-7.5 cm depth was also significantly greater than that of the NPK (10.53 x 10(-6) m s(-1)) and control (8.61 x 10(-6) m s(-1)) treatments. The lowest bulk density (1.18 Mg m(-3)) in the 0-7.5 cm layer was recorded in NPK+FYM whereas it was highest in the control plots (1.30 Mg m(-3)). However, at sub-surface (22.5-30 cm) layer, fertilizer and manure application had little effect on bulk density and saturated hydraulic conductivity. Root length density (RLD) up to the 30 cm depth was highest in the NPK+FYM plots and it was 31.9% and 70.5% more than NPK and control plots. The RLD showed a significant and negative correlation (r=-0.88( * *)) with the penetration resistance.


Assuntos
Agricultura/métodos , Produtos Agrícolas/crescimento & desenvolvimento , Fertilizantes , Glycine max/crescimento & desenvolvimento , Esterco , Raízes de Plantas/crescimento & desenvolvimento , Solo/análise , Animais , Biomassa , Índia
8.
Phys Rev E Stat Nonlin Soft Matter Phys ; 71(5 Pt 2): 057701, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-16089706

RESUMO

We present a technique for entropy optimization to calculate a distribution from its moments. The technique is based upon maximizing a discretized form of the Shannon entropy functional by mapping the problem onto a dual space where an optimal solution can be constructed iteratively. We demonstrate the performance and stability of our algorithm with several tests on numerically difficult functions. We then consider an electronic structure application, the electronic density of states of amorphous silica, and study the convergence of the Fermi level with increasing number of moments.

9.
J Biochem ; 130(1): 141-8, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11432790

RESUMO

The role that interaction with laminin may play in Leishmania donovani infection was investigated. Binding of (125)I-radiolabeled laminin, in a liquid-phase assay, by the parasite was rapid, saturable, specific, reversible, and of high affinity. Using a Western blotting procedure, a 67 kDa laminin-binding protein (LBP) was identified from the membrane of both the promastigote and amastigote forms of L. donovani. Subsequently, the protein was purified by affinity chromatography. Immunofluorescence with a polyclonal antibody against LBP as well as flow cytometric analysis demonstrated its presence at the parasite surface. After stimulation with phorbol-12-myristate-13-acetate (PMA), U937 cells exhibited the ability to adhere to laminin and LBP specifically inhibited this adhesion. The reduced parasite adhesion after tunicamycin treatment suggested the importance of sugar residues in cell adhesion. Although co-administration of either laminin or LBP or anti LBP antibody reduced parasite virulence, resulting in a lower level of infection in the BALB/c mouse model, an in vitro macrophage culture-enhanced level of infection was observed in the case of laminin-coated parasites. The results collectively suggest a role for LBP in the interaction of the parasite with extracellular matrix elements, which may constitute a basis for the homing of the parasite to its physiological address.


Assuntos
Laminina/metabolismo , Leishmania donovani/metabolismo , Leishmania donovani/patogenicidade , Proteínas de Membrana/química , Proteínas de Membrana/metabolismo , Animais , Anticorpos/farmacologia , Anticorpos/uso terapêutico , Antígenos de Superfície/química , Antígenos de Superfície/isolamento & purificação , Antígenos de Superfície/metabolismo , Western Blotting , Adesão Celular/efeitos dos fármacos , Citometria de Fluxo , Humanos , Laminina/farmacologia , Laminina/uso terapêutico , Leishmania donovani/química , Leishmania donovani/efeitos dos fármacos , Leishmaniose Visceral/tratamento farmacológico , Leishmaniose Visceral/metabolismo , Leishmaniose Visceral/parasitologia , Leishmaniose Visceral/patologia , Proteínas de Membrana/antagonistas & inibidores , Proteínas de Membrana/isolamento & purificação , Camundongos , Camundongos Endogâmicos BALB C , Microscopia de Fluorescência , Peso Molecular , Ligação Proteica/efeitos dos fármacos , Acetato de Tetradecanoilforbol/farmacologia , Fatores de Tempo , Tunicamicina/farmacologia , Células U937 , Virulência/efeitos dos fármacos
10.
J Org Chem ; 65(11): 3292-8, 2000 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-10843608

RESUMO

The synthesis and electrochemistry of a series of tetrathiafulvalene (TTF) and dithia-crown-TTF derivatives attached with one or two disulfide group(s) 7a-f are reported. The self-assembled monolayers (SAMs) of these TTF disulfides on gold were prepared and characterized by reflection-absorption infrared spectroscopy. The SAMs are extremely stable under a wide variety of conditions and over extended periods of time and show remarkable electrochemical stability upon repeated potential scans. SAMs of the crown-TTF disulfides 7c,d,f can recognize alkali metal ions, and the process can be monitored following the electrochemical potential shift of the surface-confined TTF group.

11.
Bioresour Technol ; 95(1): 77-83, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15207299

RESUMO

A field experiment was conducted on deep vertisols of Bhopal, India to evaluate the manural potential of three organic manures: farmyard manure (FYM), poultry manure (PM), phosphocompost (PC) vis-a-vis 0%, 75% and 100% recommended dose of fertilizer-NPK and to find out the most productive cropping system at various combinations of organic manures and chemical fertilizers. The seed yield of intercrop soybean (population converted to 100%) was 8.7% less than sole soybean whereas the grain yield of intercrop sorghum was 9.5% more than that of sole sorghum. However, the productivity in terms of soybean equivalent yield (SEY) was relatively high in intercropping system. The increasing NPK dose from 0% to 100% significantly improved SEY in sole sorghum and soybean/sorghum intercropping system and the integrated use of organics and inorganics recorded significantly more SEY than inorganics. The effect of nutrient management followed the order; 75% NPK + 5 t FYM ha(-1) > 75% NPK + 1.5 t PM ha(-1) > 75% NPK + 5 t PC ha(-1) > 100% NPK. Sorghum, both as sole and intercrop, responded more to PM while soybean to FYM. Application of 75% NPK in combination with PM or FYM or PC to preceding rainy season crops (soybean and sorghum) and 75% NPK to wheat produced significantly higher grain yield of wheat than those in inorganics and control indicating noticeable residual effect on the succeeding wheat crop and saving of 25% fertilizer-NPK. The effect of PC on rainy season crops was not as prominent as those of FYM and PM, but its residual effect on grain yield of wheat was comparable to those two organic manures. Among the cropping systems, soybean as preceding crop recorded the highest seed yield of wheat and was on a par with that of soybean/sorghum intercropping system. The yield of wheat following sorghum was the lowest. The total system productivity (TSP) was the highest in sorghum + soybean-wheat system and the lowest in the soybean-wheat system.


Assuntos
Agricultura/métodos , Produtos Agrícolas , Fertilizantes , Esterco , Animais , Bovinos , Índia , Fósforo , Aves Domésticas , Chuva , Estações do Ano , Glycine max , Triticum , Clima Tropical
12.
Bioresour Technol ; 95(1): 85-93, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15207300

RESUMO

A field experiment was conducted on a deep Vertisol of Bhopal, India to compare root and shoot biomass, chlorophyll content, enzyme activity and nodulation in three cropping systems at three combinations of organic manure and inorganic-fertilizer: 75%NPK + 5 t farmyard manure (FYM), 75%NPK + 1.5 t poultry manure (PM), and 75%NPK + 5 t phosphocompost (PC) vis-a-vis 0%, 75% and 100% of fertilizer-NPK. In general, nodule number and its mass were lower in intercrop soybean than sole soybean. Also there was decrease in the nodule number with higher NPK dose. The FYM treated plots recorded 22.0% and 7.6% higher nodule mass than poultry manure and phosphocompost plots, respectively. Also, the total chlorophyll content was higher in organically treated plots than that in 100% NPK particularly at 30 days after sowing (DAS, pre-flowering). In sorghum the peak nitrate reductase (NR) activity was recorded at 60 DAS while in soybean it was at 30 DAS. The NR activity was higher in intercrop sorghum than that in sole sorghum. Maximum NR activity was observed in 100% NPK. Soybean/sorghum intercropping system recorded significantly higher root and shoot biomass than sole soybean and sorghum. The crop growth rates were relatively rapid during 30-60 DAS and followed the order; intercropping > sole sorghum > sole soybean. With the increase in NPK dose from 0% to 100% there was significant improvement in the dry matter (DM) production in sole sorghum and soybean/sorghum intercropping system. Soybean as preceding crop recorded the highest DM, chlorophyll content, NR activity in wheat while these values were the lowest in sorghum-wheat system.


Assuntos
Agricultura/métodos , Clorofila/análise , Enzimas/análise , Fertilizantes , Esterco , Animais , Bovinos , Produtos Agrícolas , Enzimas/metabolismo , Índia , Nitrato Redutase , Nitrato Redutases/análise , Nitrato Redutases/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Aves Domésticas , Chuva , Solo , Sorghum/química , Glycine max/química , Glycine max/metabolismo , Triticum/química
14.
Biotechnol Bioeng ; 24(4): 797-804, 1982 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18546371

RESUMO

Recently, considerable interest has been shown in the study and analysis of immobilized cell reactors. One of the major uses of such a reactor system is expected to be in ethanol production from carbohydrates. One distinct disadvantage of this system is carbon dioxide gas holdup associated with unsteady-state temperature distribution across the reactor. Taking into account the earlier published data and assuming steady-state-substrate balance, and unsteady-state energy balance, and an average gas holdup of 20% with the heat retained by the gas neglected, the average reaction rate in the differential element was computed. Finally, a mathematical model to predict steady-state temperature profile along the reactor was developed. It was verified with experimental data obtained from an immobilized yeast reactor column (1 m x 14.5 cm). The experimental data fit well those computed from the model within an accuracy of 5%.

15.
Biotechnol Bioeng ; 24(4): 805-15, 1982 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18546372

RESUMO

In earlier communications general analyses of rapid ethanol fermentation by Saccharomyces cerevisiae immobilized on inert supports were described. In this article physiology of growth and metabolism (parameters like rates of CO(2) evolution and O(2) uptake, respiratory quotient, and generation time) of Saccharomyces cerevisiae immobilized on different supports are reported. Values of the ratio of specific oxygen uptake rate for immobilized cells to free cells have been found to be 0.732, 0.781 and 0.785 for carrier A, carrier B, and covalently crosslinked controlled pore glass (CPG, specific surface area of 439 m(2) g(-1)), respectively. Rates of specific CO(2) evolution for immobilized cells to free cells for these supports are 0.784, 0.822, and 0.783, respectively. Marked reduction in generation time of Saccharomyces cerevisiae on all the supports has been observed. No change in size (4.8-5 microm) and specific growth rate (micro(m) = 0.275 h(-1)) of cells leaving the reactor has been observed.

16.
Health Care Manage Rev ; 25(2): 74-84, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10808419

RESUMO

HMOs are becoming increasingly reliant on health management information systems (HMISs) for their effective functioning, competitive viability, and survival. Because of this critical dependence, HMOs must use disaster recovery planning (DRP) to safeguard their HMIS assets from natural as well as man-made disasters. This article purposes a theoretical framework, based on the theory of organizational innovation, to explain the factors involved in the adoption of DRP by HMOs.


Assuntos
Planejamento em Desastres/organização & administração , Sistemas Pré-Pagos de Saúde/organização & administração , Sistemas de Informação Administrativa , Gestão de Riscos/organização & administração , Pessoal Administrativo/psicologia , Atitude , Humanos , Percepção
17.
Chemistry ; 6(23): 4385-92, 2000 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-11140969

RESUMO

Self-assembled monolayers (SAMs) of bis-thioctic ester derivatives of oligoethylene glycols were prepared. When the number of (-CH2-CH2-O-)n units in these podands was either five or six, the corresponding SAMs showed ion binding properties and selectivities similar to those exhibited by 15-crown-5 or 18-crown-6 in aqueous solution, respectively. Impedance data for the SAMs as a function of metal ion concentrations were fitted by using a Langmuir isotherm to determine the association constants (Ka) with the different ions. The SAM derived from the n = 5 compound is selective for Na+ while that with n = 6 is selective for K+. Results presented here confirm the formation of ion recognition domains during self-assembly of acyclic polyethylene glycol derivatives on gold surfaces; this suggests that surface-confined pseudocrown ether structures are formed.

18.
Biochem J ; 337 ( Pt 3): 551-8, 1999 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-9895301

RESUMO

Extracellular matrix (ECM)-binding proteins on the surface of Leishmania are thought to play a crucial role in the onset of leishmaniasis, as these parasites invade mononuclear phagocytes in various organs after migrating through the ECM. In a previous report, we presented several lines of evidence suggesting that Leishmania has a specific receptor for laminin, a major ECM protein, with a Kd in the nanomolar range. Here we describe the identification, purification and biochemical characterization of the Leishmania laminin receptor. When the outer membrane proteins of L. donovani were blotted on to nitrocellulose paper and probed with laminin, a prominent laminin-binding protein of 67 kDa was identified. The purified protein was isolated by a three-step process involving DEAE-cellulose, Con A (concanavalin A)-Sepharose and laminin-Sepharose affinity chromatography and was used to raise a monospecific antibody. The same protein was obtained when parasite membrane extracts were adsorbed to antibody affinity matrix and eluted with glycine. The affinity-purified protein bound to laminin in a detergent-solubilized form as well as after integration into artificial bilayers, and was subsequently characterized as an integral membrane protein. Metaperiodate oxidation and metabolic inhibition of glycosylation studies indicate the binding protein to be glycoprotein in nature and that N-linked oligosaccharides play a part in the interaction of laminin with the binding protein. Surface-labelled parasites attached to microtitre wells coated with laminin and the 67 kDa protein blocked the adhesion to laminin substrate. We propose that the 67 kDa protein is an adhesin involved in the attachment of Leishmania to host tissues.


Assuntos
Leishmania donovani/química , Receptores de Laminina/isolamento & purificação , Animais , Adesão Celular , Laminina/metabolismo , Laminina/fisiologia , Leishmania donovani/fisiologia , Lipossomos , Testes de Precipitina , Receptores de Laminina/metabolismo , Receptores de Laminina/fisiologia
19.
Biochem Biophys Res Commun ; 226(1): 101-6, 1996 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-8806598

RESUMO

Both the promastigote and amastigote forms of the intracellular parasite, Leishmania donovani bind the basement membrane glycoprotein laminin with high affinity (Kd = 3.56 x 10(-9) M and 3.98 x 10(-9) M respectively) with approximately 9000 and approximately 800 sites per cell. Bound laminin was identified by direct autoradiography and the binding protein through analysis of the parasite extract by SDS-PAGE and immunoblotting. A major component of 67 kDa was detected. The same protein was obtained when parasite outer membrane proteins were adsorbed to laminin-sepharose affinity matrix and subsequently eluted with SDS. The binding affinity of the isolated receptor was similar to that of the whole cells. Such a receptor isolated in Leishmania for the first time, may function as one of the bridging molecules for extracellular matrix recognition.


Assuntos
Leishmania donovani/metabolismo , Receptores de Laminina/metabolismo , Animais , Membrana Basal/metabolismo , Membrana Celular/metabolismo , Eletroforese em Gel de Poliacrilamida , Matriz Extracelular/metabolismo , Leishmania donovani/fisiologia , Receptores de Laminina/isolamento & purificação
20.
Biotechnol Bioeng ; 26(9): 1114-21, 1984 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18553534

RESUMO

Surface culture citric acid fermentation was carried out by Aspergillus niger T55, a strain isolated from its natural source, using cane molasses, either untreated or treated by various methods. Citric acid biosynthesis is seriously impaired by both organic and inorganic inhibitors. A combined treatment of molasses with tricalcium phosphate, hydrochloric acid, and Sephadex fractionation minimizes the level of inorganic and organic inhibitors in molasses and increases the production of citric acid (65% weight yield based on total reducing sugar). The optimum level of individual metal ions for citric acid production depends on the concentration of other metals in the medium.

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