11 research outputs found

    The role of apolipoprotein N-acyl transferase, Lnt, in the lipidation of factor H binding protein of Neisseria meningitidis strain MC58 and its potential as a drug target

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    BACKGROUND AND PURPOSE The level of cell surface expression of the meningococcal vaccine antigen, Factor H binding protein (FHbp) varies between and within strains and this limits the breadth of strains that can be targeted by FHbp-based vaccines. The molecular pathway controlling expression of FHbp at the cell surface, including its lipidation, sorting to the outer membrane and export, and the potential regulation of this pathway have not been investigated until now. This knowledge will aid our evaluation of FHbp vaccines. EXPERIMENTAL APPROACH A meningococcal transposon library was screened by whole cell immuno-dot blotting using an anti-FHbp antibody to identify a mutant with reduced binding and the disrupted gene was determined. KEY RESULTS In a mutant with markedly reduced binding, the transposon was located in the lnt gene which encodes apolipoprotein N-acyl transferase, Lnt, responsible for the addition of the third fatty acid to apolipoproteins prior to their sorting to the outer membrane. We provide data indicating that in the Lnt mutant, FHbp is diacylated and its expression within the cell is reduced 10 fold, partly due to inhibition of transcription. Furthermore the Lnt mutant showed 64 fold and 16 fold increase in susceptibility to rifampicin and ciprofloxacin respectively. CONCLUSION AND IMPLICATIONS We speculate that the inefficient sorting of diacylated FHbp in the meningococcus results in its accumulation in the periplasm inducing an envelope stress response to down-regulate its expression. We propose Lnt as a potential novel drug target for combination therapy with antibiotics

    Hair coat characteristics of saanen and oberhasli goats in tropical environments.

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    The aim of the present work was to study the morphological characteristics of the hair coat, coat thickness (E), hair length (C), number of hair by unit area (N), hair angle to skin (A) and hair diameter (D) of Saanen and Oberhasli goats, measured under the conditions of tropical environment. The observed averages of these traits were: E= 6.04±0.08 mm; C= 33.17±0.24 mm; N= 191.50±4.67 hairs.cm-2; A= the 10.67±0.15 degrees; D= 0.203±0.0013 mm.Realizou-se um estudo das seguintes características morfológicas do pelame: espessura da capa (E), comprimentos médios dos pêlos (C), número de pêlos por área (N), ângulo de inclinação dos pêlos em relação à superfície (A) e diâmetro médio dos pêlos (D) em 532 cabras das raças Saanen e Pardo Alpina criadas em ambiente tropical As médias e erros-padrões dessas características foram: E= 6,04±0,08 mm; C= 33,17±0,24 mm; N= 191,50±4,67 pêlos.cm-2; A= 10,67±0,15 graus e D= 0,203±0,0013 mm

    Thermoregulatory responses of saanen and oberhasli goats in tropical environments.

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    À forma mais eficaz de termólise quando a carga térmica do ambiente está elevada é a evaporação, uma vez que esse mecanismo não depende do gradiente térmico entre o ambiente e o animal. Deste modo realizou-se observações sobre as resposta termorreguladoras, taxa de sudação (TS), frequência respiratória (FR) e temperatura retal (TR) em 484 cabras das raças Saanen e Pardo Alpina criadas em ambiente tropical. As médias e erros-padrões dessas características foram: TS= 142,91 ± 4,02 g.m-2h-1; FR= 73,23 ± 1,60 mov.min-1; TR= 39,28 ± 0,02ºC.Evaporation is the most effective way of thermolysis with high environmentmal heat load. This mechanism does not depend on the thermal gradient between the environment and animals. The aim of the present work was thermoregulatory responses, sweating rate (TS), rate frequency (FR) e rectal temperature (TR) of Saanen and Oberhasli goats under tropical environment conditions. The observed averages of responses were: TS= 142.91 ± 4.02 g.m-2h-1; FR= 73.23 ± 1.60 mov.min-1; TR= 39.28 ± 0.02ºC

    The beauty in product-service systems

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    Aesthetic appreciation affects the success of products in a number of areas, such as user satisfaction and usability. Hence, designers apply aesthetic principles to create more successful products. However, it is still unclear how such principles apply to the services and systems that products are often part of. In this paper, we explore how two aesthetic principles, which are known to influence product aesthetics, can be extended to product-service systems. These principles are Unity-in-Variety and Maximum-Effect-for-Minimum-Means. According to the former principle, aesthetic pleasure can be attained from perceiving as much variety as possible within a unified whole; according to the latter, it can be attained from perceiving efficiency. With the qualitative study here presented, we showed how the principles could also describe product-service systems in terms of their sensory properties, underlying mechanism and human interaction. We thereby offer a basis to further investigate and enhance the aesthetics of product-service systems.Industrial DesignIndustrial Design Engineerin

    Uso de lodo de esgoto na produção de tapetes de grama esmeralda Use of sewage sludge in zoysiagrass production

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    Com objetivo de avaliar o efeito do lodo de esgoto na formação e qualidades de tapetes de grama, foi instalado, em Itapetininga, São Paulo (SP), o experimento utilizando grama Zoysia japonica Steud., conhecida como esmeralda. O delineamento experimental utilizado foi o de blocos ao acaso em parcelas subdivididas, com quatro repetições, sendo as parcelas principais constituídas de cinco doses de lodo (0, 10, 20, 30 e 40Mg ha-1, base seca), mais um tratamento com NPK, de acordo com as necessidades da cultura e as subparcelas com dois sistemas de manejo (com e sem o uso de escarificador utilizado para romper uma camada superficial compactada). Utilizou-se o lodo da Estação de Tratamento de Esgoto de Jundiaí, SP. As doses de lodo aplicadas correspondem às doses de 100, 200, 300 e 400kg ha-1 de nitrogênio. Após 165 dias da aplicação do lodo de esgoto, a dose de 31Mg ha-1 permitiu o fechamento completo (100% da taxa de cobertura do solo) e a maior resistência dos tapetes de grama. O mesmo resultado foi encontrado quando utilizou-se a adubação química. A testemunha e as parcelas que receberam 10Mg ha-1 de lodo não formaram tapete. O lodo de esgoto aplicado em superfície promoveu redução da massa dos tapetes de grama esmeralda. O uso do escarificador reduziu a resistência dos tapetes de grama esmeralda. Os valores de metais pesados encontrados no lodo de esgoto estavam abaixo do limite estabelecido pelas normas que regulamenta a utilização do lodo de esgoto na agricultura.<br>Aiming to evaluate sewage sludge effect in the grass sod qualitiy and formation it was installed in Itapetininha - SP one experiment using Zoysia japonica Steud. The experimental design adopted was randomized blocks with split plot design, with four replications, the main plots consisting of five doses of sludge (0, 10, 20, 30 and 40Mg ha-1, a dry basis), another treatment with NPK, according to the requirement of the culture, and subplots with two management systems (with and without chisel use, to break a compacted surface layer). The sludge used came from "Estação de Tratamento de Esgoto de Jundiaí/SP". The doses of sludge applied correspond to the doses of 100, 200, 300 and 400kg ha-1 of nitrogen. 165 days after sewage sludge application, the dose of 31Mg ha-1 allowed the complete closing (100% of soil cover rate) and greater resistance of the zoysiagrass sod. The same results were found when chemical fertilization was used. The control and the plots that received 10Mg ha-1 of sludge did not formed sod. The sewage sludge applied to surface promoted reduction of zoysiagrass sod mass. The use of surface chisel reduced the strength of zoysiagrass sod. The heavy metals values found in sewage sludge were below the limit set by the rules governing the sewage sludge use in agriculture
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