Proteomic analysis of secreted membrane vesicles of archaeal Sulfolobus species reveals the presence of endosome sorting complex components

The crenarchaea Sulfolobus acidocaldarius, S. solfataricus and S. tokodaii, release membrane vesicles into the medium. These membrane vesicles consist of tetraether lipids and are coated with an S-layer. A proteomic analysis reveals the presence of proteins homologous to subunits of the eukaryotic endosomal sorting complex required for transport (ESCRT). Immunodetection of one of these homologs suggest a cell surface localization in intact cells. These data suggest that the membrane vesicles in Sulfolobus sp. emerge from a specific budding process with similarity to the endosomal sorting pathway.     

Optimisation of physical factors on the production of active metabolites by Bacillus subtilis 355 against wood surface contaminant fungi

A Surface Response Model was used to study the effect of pH, temperature and agitation on growth, sporulation and production of antifungal metabolites by Bacillus subtilis CCMI 355.Strong agitation, temperature between 27 and 34 °C and pH 6 favoured cell growth. Alkaline pH, strong agitation and temperature between 28 and 34 °C favoured spore formation. No relationship was found between sporulation and the production of antifungal metabolites. According to the model, pH 8, 37 °C and the absence of agitation were the optimal conditions for the production of broad-spectrum antifungal metabolites against Botrytis cinerea, Penicillium expansum, Trichoderma sp, Trichoderma harzianum, Trichoderma koningii and Trichoderma virgatum.In situ assays using green wood impregnated with Bacillus subtilis CCMI 355 inoculated in Yeast Extract Glucose Broth medium in the conditions above, displayed an efficient protection against wood surface contaminant fungi.     

Construction of efficient bioelectrochemical devices: Improved electricity production from cyanobacteria (Leptolyngbia sp.) based on π-conjugated conducting polymer/gold nanoparticle composite interfaces

In this study, gold electrodes (GE) were coated with conducting polymers to obtain a high photocurrent using cyanobacteria from a novel bioelectrochemical fuel cell. For this purpose, 4-(4H-ditiheno[3,2-b:2',3'-d]pyrol-4-yl) aniline and 5-(4H-dithieno[3,2-b:2',3'-d]pyrol-4-yl) napthtalane-1-amine monomers were coated on GE by performing an electropolymerization process. After that, gold nanoparticles (AuNP) were specifically modified by 2-mercaptoethane sulfonic acid and p-aminothiophenol to attach to the electrode surface. The conducting polymers GE coat was modified with functionalized AuNP using a cross-linker. The resulting electrode structures were characterized by cyclic voltammetry and chronoamperometry under on-off illumination using a fiber optic light source. Cyanobacteria Leptolyngbia sp. was added to the GE/conducting polymer/AuNP electrode surface and stabilized by using a cellulose membrane. During the illumination, water was oxidized by the photosynthesis, and oxygen was released. The released oxygen was electrocatalytically reduced at the cathode surface and a 25 nA/cm ² photocurrent was observed in GE/ Leptolyngbia sp. After the electrode modifications, a significant improvement in the photocurrent up to 630 nA/cm ² was achieved.     

Solubility-modulated asymmetric membrane tablets of triprolidine hydrochloride: statistical optimization and evaluation

The aim of the present study was to develop asymmetric membrane (AM) tablets for controlled delivery of highly water-soluble antihistaminic drug triprolidine hydrochloride. The solubility of triprolidine hydrochloride was modulated through the incorporation of coated sodium chloride crystals encapsulated with asymmetric membrane coating polymer, cellulose acetate butyrate. Formulation of AM tablets was based on a 2³ factorial design to study the effect of formulation variables, namely, polymer concentration, level of pore former, and amount of osmogen on the in vitro release. Core tablets prepared by wet granulation and coated with asymmetric membrane by a dip coating method were evaluated. Statistical analysis was done with the Design Expert Software 8.0.2 (USA), and the polynomial equation generated by Pareto charts was used for validation of the experimental design. The interaction chart and response surface plots deduced the simultaneous effect of independent variables on in vitro drug release. The in vitro drug release was inversely proportional and directly related to the level(s) of polymer and pore former in the membrane, respectively. The level of osmogen not only increased the osmotic pressure but also controlled the drug release due to a common ion effect. The drug release of the optimized formulation (F6) followed zero-order kinetics, which would be capable of reducing the administration, and was stable over 3 months. SEM photographs revealed asymmetry in membrane structure.     

Design,Synthesis, and Antifungal Activities of Novel 1,2,4‐Triazole Schiff Base Derivatives

With the aim to find new compounds with high antifungal activity, 21 4‐amino‐5‐substituted‐1,2,4‐triazole Schiff bases ( 2a  –  2g , 3a  –  3g , and 4a  –  4g ) were designed and synthesized. Their antifungal activities against Pythium solani, Gibberlla nicotiancola, Fusarium oxysporium f. sp. niveum, Gibberlla saubinetii, Alternaria iycopersici, Phytophthora capsici, Physalospora piricola, Cercospora arachidicola hori, and Fusarium oxysporium f. sp. cucumber were tested, parts of the compounds exhibited excellent antifungal activity. This research provides useful information for further study of antifungal agents.     

Screening of antifungal activity of various plant leaves extracts from Indian plants

The present study was designated to evaluate the antifungal activity and to root out the antifungal plant leaf extracts from this Indian folk-flore. The in vitro antifungal assay was performed by agar diffusion test and minimum inhibitory concentration (MIC) for hexane, ethyl acetate, methanol and distilled water plant leaf extracts. Extraction of 17 different plant leaves was carried out in different solvents such as hexane, ethyl acetate, methanol and distilled water. Among them extractive yield of methanol was maximum than the rest of the three solvents. These extracts were screened for their antifungal activity against nine different fungi. Among these ethyl acetate extracts of Adhatoda vasica, Ocimum sanctum and Holoptelea integrifolia exhibited maximum antifungal activity against Alternaria sp., Aspergillus parasi, Aspergillus nidulans, Trichoderma harzianum and Aspergillus flavus with MIC of 80, 40 and 20 ppm against Aspergillus nidulans and Alternaria sp. Ethyl acetate extracts showed promising antifungal activity against Adhatoda vasica, Ocimum sanctum and Holoptelea integrifolia against Aspergillus nidulans, and Alternaria sp. might be applicable as fungicide against fungal plants disease.     

Silica gel dissication of amniotic membrane with related epithelium cells for ocular surface reconstruction

Cornea reparative regeneration when in various pathological states needs creating certain conditions to intensify the potential of regional stem cells mitotic activity. Aims of the Research. To find out the degree of the epithelium AM preservation after preliminary processing and conservation by means of dehydration over silica gel with further sterilization; to study the effectiveness of clinical treatment of AM conserved in the surroundings with vital ability epithelium and AM dried over silica gel. Materials and methods. There was carried out an investigation of 18 samples of native amnion treated with antibiotics and 18 total surface amnion samples conserved by drying over silica gel and then sterilized by gamma rays. Clinical experiments were carried out on patients with severe chemical and thermal burns – 18 people (21 eyes). After the burn trauma all the patients underwent the standard procedure of necrectomy, the covering of the eyeball with amniotic membrane dried over silica gel. Conclusion. The drying out of the amniotic membrane over silica gel on frames without being fixed on nitrocellulose paper makes the process of the amniotic membrane conservation simpler and makes it possible to preserve its unique biological qualities. The effectiveness of the regeneration of epithelium tissue of the eyeball surface with amniotic membrane dried over silica gel without the vital capacity cells of the epithelium layer is analogous to the regeneration of epithelium cells with amniotic membrane with vital capacity cells. With eye burns AM coverage hinders the formation of rough conjunctiva cicatrix, provides a favorable out-of-cell matrix substrate for epithelium migration and leads to quicker regeneration of one's own epithelium, makes further visual rehabilitation simpler. This revised version was published online in July 2006 with corrections to the Cover Date.     

Impact of antifungals producing rhizobacteria on the performance of Vigna radiata in the presence of arbuscular mycorrhizal fungi

Plant growth-promoting rhizobacteria (PGPR) that produce antifungal metabolites are potential threats for the arbuscular mycorrhizal (AM) fungi known for their beneficial symbiosis with plants that is crucially important for low-input sustainable agriculture. To address this issue, we used a compartmented container system where test plants, Vigna radiata, could only reach a separate nutrient-rich compartment indirectly via the hyphae of AM fungi associated with their roots. In this system, where plants depended on nutrient uptake via AM symbiosis, we explored the impact of various PGPR. Plants were inoculated with or without a consortium of four species of AM fungi (Glomus coronatum, Glomus etunicatum, Glomus constrictum, and Glomus intraradices), and one or more of the following PGPR strains: phenazine producing (P⁺) and phenazine-less mutant (P⁻), diacetylphloroglucinol (DAPG) producing (G⁺) and DAPG-less mutant (G⁻) strains of Pseudomonas fluorescens, and an unknown antifungal metabolite-producing Alcaligenes faecalis strain, SLHRE425 (D). PGPR exerted only a small if any effect on the performance of AM symbiosis. G⁺ enhanced AM root colonization and had positive effects on shoot growth and nitrogen content when added alone, but not in combination with P⁺. D negatively influenced AM root colonization, but did not affect nutrient acquisition. Principal component analysis of all treatments indicated correlation between root weight, shoot weight, and nutrient uptake by AM fungus. The results indicate that antifungal metabolites producing PGPR do not necessarily interfere with AM symbiosis and may even promote it thus carefully chosen combinations of such bioinoculants could lead to better plant growth.     

Antifungal mechanism of a cysteine-rich antimicrobial peptide, Ib-AMP1, from Impatiens balsamina against Candida albicans

The antifungal mechanism of a 20-mer peptide, Ib-AMP1, derived from Impatiens balsamina was investigated. The oxidized (disulfide bridged) Ib-AMP1 showed a 4-fold increase in antifungal activity against Aspergillus flavus and Candida albicans than reduced (non-disulfide bridged) Ib-AMP1. Ib-AMP1 had very low activity for phospholipid disruption when compared with cecropin A(1-8)-magainin 2(1-12), a -helical amphiphatic, antimicrobial peptide. Confocal microscopy showed that Ib-AMP1 binds on cell surface or penetrates into cell membranes. These results suggested that Ib-AMP1 may manifest its antifungal activity against Candida albicans by inhibiting a distinct cellular process rather than ion channel or pore formation in cell membrane.     

黄花倒水莲内生真菌生物活性评价及HNLF-44菌株鉴定

为充分开发黄花倒水莲(Polygala fallax)的内生真菌资源，获得具有抗植物病原真菌、抗氧化活性的内生真菌，该文以黄花倒水莲内生真菌为研究对象，使用平板对峙法检测内生真菌对6种植物病原真菌的抑菌活性，测定内生真菌发酵液的DPPH清除自由基能力和总还原能力，评价内生真菌的抗氧化活性，并对具有强抑菌活性和抗氧化活性的菌株进行形态和ITS鉴定。结果表明：(1)黄花倒水莲内生真菌中有2株内生真菌对香蕉专化尖孢镰刀菌、柑橘树脂病菌、叶点霉菌、香蕉具条叶斑病菌、茄病镰刀菌、三七根腐病菌具有明显的抑菌活性，抑菌率在50.3%～91.4%之间，其中HNLF-5对柑橘树脂病菌的抑菌率为73.2%,HNLF-44对香蕉专化尖孢镰刀菌抑菌率为91.4%。(2)内生真菌发酵液具有良好的抗氧化活性，DPPH清除率均在80%以上，总还原能力吸光值范围为0.279 2～0.748 8。(3)HNLF-44菌株为链格孢属真菌。该研究表明，药用植物黄花倒水莲内生真菌具有较好的生物活性，为后续从黄花倒水莲内生真菌中挖掘潜在新型抑菌活性和抗氧化活性物质奠定了基础。     

Ectomycorrhizal and arbuscular mycorrhizal colonization of Alnus acuminata from Calilegua National Park (Argentina)

The objective of this study was to determine patterns of ectomycorrhizas (ECM) and arbuscular mycorrhizas (AM) colonization associated with Alnus acuminata (Andean alder), in relation to soil parameters (electrical conductivity, field H₂O holding capacity, pH, available P, organic matter, and total N) at two different seasons (autumn and spring). The study was conducted in natural forests of A. acuminata situated in Calilegua National Park (Jujuy, Argentina). Nine ECM morphotypes were found on A. acuminata roots. The ECM colonization was affected by seasonality and associated positively with field H₂O holding capacity, pH, and total N and negatively associated with organic matter. Two morphotypes (Russula alnijorullensis and Tomentella sp. 3) showed significant differences between seasons. Positive and negative correlations were found between five morphotypes (Alnirhiza silkacea, Lactarius omphaliformis, Tomentella sp. 1, Tomentella sp. 3, and Lactarius sp.) and soil parameters (total N, pH, and P). A significant negative correlation was found between field H₂O holding capacity and organic matter with AM colonization. Results of this study provide evidence that ECM and AM colonization of A. acuminata can be affected by some soil chemical edaphic parameters and indicate that some ECM morphotypes are sensitive to changes in seasonality and soil parameters.     

Bioactive secondary metabolites from <Emphasis Type="Italic">Nigrospora</Emphasis> sp. LLGLM003, an endophytic fungus of the medicinal plant <Emphasis Type="Italic">Moringa oleifera</Emphasis> Lam.

An endophytic fungus was isolated from the root of the medicinal plant Moringa oleifera Lam. Based on analyzing the rDNA sequence, the fungus was identified as Nigrospora sp. This is the first report of the isolation of endophytic Nigrospora from M. oleifera. By bioassay-guided fractionation, four antifungal secondary metabolites were isolated from liquid cultures of the fungus Nigrospora sp. LLGLM003, and their chemical structures were determined to be griseofulvin (1), dechlorogriseofulvin (2), 8-dihydroramulosin (3) and mellein (4) on the basis of spectroscopic analyses. Compound 2, 3 and 4 were isolated from Nigrospora sp. for the first time. In vitro antifungal assay showed that griseofulvin displayed clear inhibition of the growth of 8 plant pathogenic fungi. Dechlorogriseofulvin and mellein exhibited only weak antifungal activities, whereas 8-dihydroramulosin displayed no antifungal activities.     

Sulphate-reducing bacteria,palladium and the reductive dehalogenation of chlorinated aromatic compounds

The surfaces of cells of Desulfovibrio desulfuricans,Desulfovibrio vulgaris and a new strain, Desulfovibrio sp. `Oz-7' were used to manufacturea novel bioinorganic catalyst via the reduction of Pd(II) to Pd(0) at the cell surface usinghydrogen as the electron donor. The ability of the palladium coated (palladised) cells to reductivelydehalogenate chlorophenol and polychlorinated biphenyl species was demonstrated. Dried, palladisedcells of D. desulfuricans, D. vulgaris and Desulfovibrio sp. `Oz-7'were more effective bioinorganic catalysts than Pd(II) reduced chemically under H₂ orcommercially available finely divided Pd(0). Differences were observed in the catalyticactivity of the preparations when compared with each other. Negligible chloride release occurredfrom chlorophenol and polychlorinated biphenyls using biomass alone.     

Fine Structure of the Cell Surface and Golgi Apparatus of Ochromonas*

SYNOPSIS. Ochromonas danica has an unusually flexible cell surface capable of producing projections of varying sizes and shapes: large projections, 340–360 nm long, and small projections, 50–110 nm long. These projections have been demonstrated by transmission and scanning electron microscopy; some of them may break off into the medium and be the source of extracellular membranes and vesicles reported in the cell-free O. danica growth medium. Ruthenium red stained the acid mucopolysaccharide layer just outside the cell surface as well as small blebs at the cell surface. The Golgi complex of O. danica, Ochromonas malhamensis, Ochromonas sociabilis and Ochromonas sp. produced small coated vesicles which may move toward and fuse with the plasma membrane. The role of the several vesicles is unknown but possible functions are discussed.     

Antifungal activity of some marine organisms from India,against food spoilage Aspergillus strains

Crude aqueous methanol extracts obtained from 31 species of various marine organisms (including flora land faunal), were screened for their antifungal activity against food poisoning strains of Aspergillus. Seventeen species exhibited mild (+ =zone of inhibition 1–2 mm) to significant (+++ =zone of inhibition 3–5 mm) activity against one or the other strain under experiment. However, extracts of 12 species were active against all the three strains. Organisms like Salicornia brachiata(obligate halophyte), Sinularia leptocladus(Soft coral), Elysia grandifolia (Mollusks),Gorgonian sp. 2 and Haliclona sp. exhibited significant (inhibition zone of 3–5 mm) antifungal activity against one or the other strains. However,extracts of A. ilicifolius, Amphiroa sp.,Poryphyra sp., Unidentified sponge, Suberites vestigium, Sinularia compressa,Sunularia sp., Sinularia maxima, Subergorgia suberosa, Echinogorgia pseudorassopo and Sabellaria cementifera were mild (inhibition zone of 1–2 mm) to moderate(inhibition zone of 2–3 mm) active against the respective strains. The growth of A. japonicuswas significantly inhibited by the extracts ofS. leptocladus (r = 0.992, p < 0.0001)and E. grandifolia (r = 0.989, p < 0.0001).This revised version was published online in October 2005 with corrections to the Cover Date.     

Organic acids and water-soluble phenolics produced by Paxillus sp. 60/92 together show antifungal activity against Pythium vexans under acidic culture conditions

Ectomycorrhizal fungi can produce antifungal compounds in vitro as well as in symbiosis with the host plant that can reduce root diseases. The objective of this study was to isolate antifungal compounds from culture filtrate of Paxillus sp. 60/92, which can form mycorrhizas with Picea glehnii seedlings. Culture filtrate of Paxillus sp. 60/92 showed antifungal activity against Pythium vexans at pH 3–4 but not at pH 5–10, although sterile MMN-b liquid medium (pH 3–10) did not show antifungal activity. Upon separation of antifungal compounds in the culture filtrate, antifungal activity was detected in the organic acid and water-soluble phenolics fractions adjusted to pH 3. Although antifungal activity of individual fractions was lower than that of the culture filtrate, a mixture of these fractions showed antifungal activity similar to that of the culture filtrate. Furthermore, antifungal activity of oxalic acid, which is known to be produced by Paxillus involutus, was increased by mixing with the water-soluble phenolic fraction. Our findings indicate that Paxillus sp. 60/92 produces organic acids and water-soluble phenolics that together show antifungal activity at pH 3–4 against P. vexans.     

Biological control of root-rot disease complex of chickpea by AM fungi

Abstract

Six species AM fungi, namely Glomus fasciculatum, G. constrictum, G. intraradices sp., Gigaspora margarita, Acaulospora sp. and Sclerocystis sp., were used for the biological control of root-rot disease complex of chickpea caused by Meloidogyne incognita and Macrophomina phaseolina. Application of these AM fungi increase plant growth, pod number, chlorophyll, nitrogen, phosphorus and potassium contents in diseased plants and also reduced nematode multiplication and root-rot index. G. fasciculatum caused greater increase in plant growth, pod number, chlorophyll, nitrogen, phosphorus and potassium contents of pathogen inoculated plants followed by G. intaradices, G. constrictum, Sclerocystis, G. margarita and Acaulospora sp. Percent root colonization caused by G. fasciculatum was high followed by G. intaradices, G. constrictum, Sclerocystis sp., G. margarita and Acaulospora sp. Glomus fasciculatum also caused higher reduction in root-rot index, galling and nematodes multiplication while Acaulospora sp. produced the least.     

Amniotic membrane transplantation in ocular surface disorders

Chronic ocular surface disorders, which can result in severe functional impairment, have been viewed for decades as untreatable diseases. In 1995, the reintroduction of amniotic membrane transplantation (AMT), either alone or associated with limbal stem cell transplantation, has offered new hope of using tissue and cell therapy strategies to repair ocular surface disorders. Amniotic membrane (AM) has been found to exert its effects by acting as a substrate for the growth of ocular surface epithelia, by suppressing inflammation and scarring and by serving as an anti-microbial barrier. Moreover, AM has recently been used as a substrate for ex vivo expansion of corneal epithelial cells for ocular surface reconstruction. Notwithstanding the substantial agreement among Authors regarding its clinical efficacy, there are still many uncertainties regarding the fate of grafted AM and consequently the mechanisms through which it exerts its long-term effects. Further studies including controlled clinical trials with numerous cases are required to understand which ocular surface conditions are certain to benefit from AM transplantation and how its mechanical properties interact with the mediators produced to favor ocular surface reconstruction.     

The fine structure of a parasitic ciliate Terebrospira during ingestion of the exoskeleton of a shrimp Palaemonetes

The ciliated protozoan, Terebrospira chattoni, invades the exoskeleton of the shrimp, Palaemonetes pugio, eating out long galleries parallel to the surface of the exoskeleton. Solubilization of the exoskeleton occurs around an area of the elaborately infolded surface membrane at the anterior of the organism. Dissolved products of the digestion of the exoskeleton are taken into the body by the formation of coated vesicles at pores in the membrane. The surface membrane that is taken in by pinocytosis is apparently recycled by the introduction into the membrane of organelles implicated in mambrane recycling in other ciliates. Acid phosphatase can be demonstrated on the surface membrane as well as in the endocuticle around the organism.