Integrative genomic mining for enzyme function to enable engineering of a non-natural biosynthetic pathway.

The ability to biosynthetically produce chemicals beyond what is commonly found in Nature requires the discovery of novel enzyme function. Here we utilize two approaches to discover enzymes that enable specific production of longer-chain (C5-C8) alcohols from sugar. The first approach combines bioinformatics and molecular modelling to mine sequence databases, resulting in a diverse panel of enzymes capable of catalysing the targeted reaction. The median catalytic efficiency of the computationally selected enzymes is 75-fold greater than a panel of naively selected homologues. This integrative genomic mining approach establishes a unique avenue for enzyme function discovery in the rapidly expanding sequence databases. The second approach uses computational enzyme design to reprogramme specificity. Both approaches result in enzymes with >100-fold increase in specificity for the targeted reaction. When enzymes from either approach are integrated in vivo, longer-chain alcohol production increases over 10-fold and represents >95% of the total alcohol products

Energy allocation in two species of Eutardigrada

To improve our knowledge on life histories in tardigrades and the energy allocated for their reproduction and growth, we have studied two species (Macrobiotus richtersi and Hypsibius convergens) differing in evolutionary histories, diet and ways of oviposition. For both species we considered a bisexual population dwelling in the same substrate. In both species we investigated energy allocations in males with a testis rich in spermatozoa and females with an ovary containing oocytes in advanced vitellogenesis. The age of the specimens were estimated on the basis of buccal tube length and body size and the body and gonad areas were calculated using an image analysis program. In both species females reach a larger size than males. Macrobiotus richtersi has significantly longer buccal tube and wider body area than H. convergens. Statistical analyses show that buccal tube has a positive correlation with body area and gonad area. For an estimate of the relative energy allocated for reproduction in one reproductive event (relative reproductive effort = RRE), we have used the ratio between gonad area and body area. In males of both species, the absolute amount of energy and the RRE is statistically lower than that of females. Males and females of H. convergens have a RRE higher than those of M. richtersi. In M. richtersi, the gonad increases proportionally more when animals are large (old), whereas in H. convergens this direct relationship is not detectable. In M. richtersi the energy allocated for a reproductive event increases during the life of the females. In males, the increase of the gonad size is progressive during the animal life. In each reproductive event, females of H. convergens allocate a lower amount of energy in absolute value when compared to M. richtersi. Nevertheless, when considering the RRE, their investment is higher than that of M. richtersi

Levantamento pedológico semidetalhado (1:25.000) da microbacia da Água Três Unidos, Município de Vera Cruz (SP).

Este trabalho é um relato dos solos identificados no levantamento pedológico semidetalhado da microbacia da Água Três Unidos. Abrangendo aproximadamente 1.624 hectares, a microbacia situa-se no município de Vera Cruz, localizada a oeste do Estado de São Paulo, entre as coordenadas geográficas 22º13? e 22º17? de latitude sul e 49º49? e 49º52? de longitude oeste. Está inserida no compartimento geomorfológico do Planalto Ocidental Paulista e, geologicamente, é caracterizada pelos arenitos cretácicos do Grupo Bauru, Formações Marília e Adamantina. O relevo varia de plano, nos topos e planícies aluviais, a montanhoso e escarpado, nas escarpas areníticas, predominando os relevos suave ondulado sob domínio dos solos latossolizados e ondulado nas áreas de ocorrência dos Podzólicos abruptos. O tipo climático predominante é Cwa, segundo a classificação de Köppen, com temperatura média anual de 21,4 ºC e pluviosidade média anual próxima a 1.500 mm. A cultura do café está entre as de maior importância nos relevos plano e suave ondulado sob domínio dos solos latossolizados, enquanto as pastagens estendem-se em grandes áreas dominadas com os Podzólicos abruptos eutróficos e álicos. Foram identificadas e cartografadas 9 unidades de solos na microbacia da Água Três Unidos, as quais apresentam uma estreita relação com o relevo. Assim, duas toposseqüências são predominantes na região. A primeira, caracteriza-se pela presença dos Latossolos Vermelho-Amarelos ou Vermelho-Escuros álicos ou distróficos nos topos aplainados, transicionando-se para os Podzólicos abruptos e Podzólicos latossólicos com o aumento da declividade, nas posições de ombro e terço superior das vertentes. Enquanto os abruptos podem ser álicos, distróficos e, predominantemente eutróficos, os Podzólicos latossólicos são essencialmente álicos ou distróficos, de textura binária arenosa/média, mais friáveis e de menor gradiente textural em relação aos Podzólicos abruptos. Sucedendo aos solos com B textural na toposseqüência, são encontrados solos poucos desenvolvidos (Solos Litólicos, Regossolos e Podzólicos abruptos rasos) nas proximidades das escarpas areníticas em relevo, predominantemente, ondulado e forte ondulado. Abaixo da escarpa, os Podzólicos abruptos são dominantes, predominantemente eutróficos, de textura binária arenosa/média e com características semelhantes àqueles localizados a montante da mesma, enquanto nas planícies aluviais predominam os solos hidromórficos (Gleissolos) e os aluviais em menores proporções. A segunda toposseqüência difere da anterior pela predominância dos Podzólicos Vermelho-Amarelos latossólicos nos topos, geralmente, mais estreitos e declivosos em relação aos locais de ocorrência de Latossolos.bitstream/CNPS/11839/1/bp12002lvtomicrobacia.pd

Vitiligo: What’s old, what’s new

Vitiligo is an acquired pigmentary disorder afflicting 0.5-2% of the world population for both sexes and all races with a capricious and unpredictable course. It has a complex etiology and varies in its manifestation, progression and response to treatment. Even if the precise aetiology and pathobiology of the disease are complex and still debated, recent evidence supports that vitiligo is a T CD8+ cell-mediated autoimmune disease triggered by oxidative stress. To date no clinical, biological and histological criteria allow us to establish the prognosis with certainty. The choice of the best therapy for adult and childhood vitiligo is based on various factors, such as the patient’s age, psychological condition and expectations, distribution and extension of skin lesions, type of vitiligo (stable or not) and availability and cost of therapeutic options. Since vitiligo has a deep psychological impact on patients and their quality of life, treating the disease is very important. As dermatologists, we have important goals in the treatment of vitiligo patients: stabilization of the disease progression, repigmentation of the lesions and especially the persistence of the aforementioned repigmentation. Although several medical and surgical therapeutic options have been proposed, no definite cure has yet been developed and the long-term persistence of repigmentation is unpredictable. We review the different therapeutic options with particular attention on the recurrence rate

Zircon ages in granulite facies rocks: decoupling from geochemistry above 850 °C?

Granulite facies rocks frequently show a large spread in their zircon ages, the interpretation of which raises questions: Has the isotopic system been disturbed? By what process(es) and conditions did the alteration occur? Can the dates be regarded as real ages, reflecting several growth episodes? Furthermore, under some circumstances of (ultra-)high-temperature metamorphism, decoupling of zircon U–Pb dates from their trace element geochemistry has been reported. Understanding these processes is crucial to help interpret such dates in the context of the P–T history. Our study presents evidence for decoupling in zircon from the highest grade metapelites (> 850 °C) taken along a continuous high-temperature metamorphic field gradient in the Ivrea Zone (NW Italy). These rocks represent a well-characterised segment of Permian lower continental crust with a protracted high-temperature history. Cathodoluminescence images reveal that zircons in the mid-amphibolite facies preserve mainly detrital cores with narrow overgrowths. In the upper amphibolite and granulite facies, preserved detrital cores decrease and metamorphic zircon increases in quantity. Across all samples we document a sequence of four rim generations based on textures. U–Pb dates, Th/U ratios and Ti-in-zircon concentrations show an essentially continuous evolution with increasing metamorphic grade, except in the samples from the granulite facies, which display significant scatter in age and chemistry. We associate the observed decoupling of zircon systematics in high-grade non-metamict zircon with disturbance processes related to differences in behaviour of non-formula elements (i.e. Pb, Th, U, Ti) at high-temperature conditions, notably differences in compatibility within the crystal structure