RESUMEN
Protein phosphorylation is known to occur in Archaea. However, knowledge of phosphorylation in the third domain of life is rather scarce. Homology-based searches of archaeal genome sequences reveals the absence of two-component systems in crenarchaeal genomes but the presence of eukaryotic-like protein kinases and protein phosphatases. Here, the influence of the offered carbon source (glucose versus tryptone) on the phospho-proteome of Sulfolobus solfataricus P2 was studied by precursor acquisition independent from ion count (PAcIFIC). In comparison to previous phospho-proteome studies, a high number of phosphorylation sites (1318) located on 690 phospho-peptides from 540 unique phospho-proteins were detected, thus increasing the number of currently known archaeal phospho-proteins from 80 to 621. Furthermore, a 25.8/20.6/53.6 Ser/Thr/Tyr percentage ratio with an unexpectedly high predominance of tyrosine phosphorylation was detected. Phospho-proteins in most functional classes (21 out of 26 arCOGs) were identified, suggesting an important regulatory role in S. solfataricus. Focusing on the central carbohydrate metabolism in response to the offered carbon source, significant changes were observed. The observed complex phosphorylation pattern hints at an important physiological function of protein phosphorylation in control of the central carbohydrate metabolism, which might particularly operate in channeling carbon flux into the respective metabolic pathways.
Asunto(s)
Proteínas Arqueales/metabolismo , Metabolismo de los Hidratos de Carbono , Fosfoproteínas/metabolismo , Proteoma/metabolismo , Sulfolobus solfataricus/metabolismo , Secuencia de Aminoácidos , Proteínas Arqueales/química , Medios de Cultivo , Glucosa/metabolismo , Anotación de Secuencia Molecular , Datos de Secuencia Molecular , Fragmentos de Péptidos/química , Peptonas/metabolismo , Fosfoproteínas/química , Fosforilación , Procesamiento Proteico-Postraduccional , Proteoma/química , Espectrometría de Masas en TándemRESUMEN
BACKGROUND: Chlamydomonas reinhardtii is a model green alga strain for molecular studies; its fully sequenced genome has enabled omic-based analyses that have been applied to better understand its metabolic responses to stress. Here, we characterised physiological and proteomic changes between a low-starch C. reinhardtii strain and the snow alga Chlamydomonas nivalis, to reveal insights into their contrasting responses to salinity stress. RESULTS: Each strain was grown in conditions tailored to their growth requirements to encourage maximal fatty acid (as a proxy measure of lipid) production, with internal controls to allow comparison points. In 0.2 M NaCl, C. nivalis accumulates carbohydrates up to 10.4% DCW at 80 h, and fatty acids up to 52.0% dry cell weight (DCW) over 12 days, however, C. reinhardtii does not show fatty acid accumulation over time, and shows limited carbohydrate accumulation up to 5.5% DCW. Analysis of the C. nivalis fatty acid profiles showed that salt stress improved the biofuel qualities over time. Photosynthesis and respiration rates are reduced in C. reinhardtii relative to C. nivalis in response to 0.2 M NaCl. De novo sequencing and homology matching was used in conjunction with iTRAQ-based quantitative analysis to identify and relatively quantify proteomic alterations in cells exposed to salt stress. There were abundance differences in proteins associated with stress, photosynthesis, carbohydrate and lipid metabolism proteins. In terms of lipid synthesis, salt stress induced an increase in dihydrolipoyl dehydrogenase in C. nivalis (1.1-fold change), whilst levels in C. reinhardtii remained unaffected; this enzyme is involved in acetyl CoA production and has been linked to TAG accumulation in microalgae. In salt-stressed C. nivalis there were decreases in the abundance of UDP-sulfoquinovose (- 1.77-fold change), which is involved in sulfoquinovosyl diacylglycerol metabolism, and in citrate synthase (- 2.7-fold change), also involved in the TCA cycle. Decreases in these enzymes have been shown to lead to increased TAG production as fatty acid biosynthesis is favoured. Data are available via ProteomeXchange with identifier PXD018148. CONCLUSIONS: These differences in protein abundance have given greater understanding of the mechanism by which salt stress promotes fatty acid accumulation in the un-sequenced microalga C. nivalis as it switches to a non-growth state, whereas C. reinhardtii does not have this response.
RESUMEN
This paper presents the carbon substrate utilisation profile of a group of microorganisms responsible for the biodegradation of a highly concentrated industrial effluent. A 1 litre bioreactor was used to study this consortium's biodegradation potential, with the chemical oxygen demand (COD) of the waste being reduced by 90% from 24000 mg l(-1) within 456 hours. This study also demonstrates that the consortium is capable of degrading organic solvents, such as isopropanol, at concentrations of 260 mg l(-1). The population distribution and biochemical behaviour were also characterised using denaturing gradient gel electrophoresis (DGGE) and Biolog Eco Plates at various stages of bioreactor operation. The DGGE results indicated that the dominant bands of the microbial population profile were stable at various operational stages, and that only a few bands varied with time. Moreover, four Biolog Eco plates were inoculated with samples drawn from the bioreactor at 0, 24, 72 and 120 hours after inoculation. Based on this Biolog Eco Plate profiling, a carbon source utilisation analysis was conducted to group the substrates according to their colour development patterns. Patterns were quantified via measurement of well optical density. Subsequently, cross-correlation statistical techniques were used to establish the existence of recurrent behavioural responses from each carbon source to the various wastewater samples. From the cross correlation, an attempt was made to classify the metabolic potential for future biodegradation processes. Carbohydrates, amino acids and carboxylic acids were the most predominant groups of sole carbon substrates showing similar growth behaviour in the consortium.
Asunto(s)
Bacterias/metabolismo , Carbono/metabolismo , Residuos Industriales , 2-Propanol/metabolismo , Biodegradación Ambiental , Reactores Biológicos , Recuento de Colonia Microbiana , ADN Bacteriano/análisis , ADN Bacteriano/genética , Electroforesis en Gel de Agar , Oxígeno/metabolismoRESUMEN
The Snell dwarf mouse (dw/dw) has no detectable PRL-binding sites in the microsomal fractions of its liver. Both bGH and bPRL, purified by preparative gel electrophoresis, induce PRL-binding sites when injected into dw/dw. Intraperitoneal injection of 100 micrograms bGH every 8 h results in the appearance of a high affinity PRL receptor 8--16 h after initiation of treatment. This induced binding capacity plateaus after 32 h of treatment and subsequently decreases to nondetectable levels 48 h after the last injection. [125I]Iodo-ovine PRL is displaced from the induced receptor equally well by similar concentrations of ovine PRL, human GH, and bovine PRL, but is displaced by bovine GH (bGH) only at approximately 100-fold higher concentrations. While untreated dw/dw livers do possess high affinity bGH-binding sites, treatment with bGH did not alter the bGH-binding activity. Treatment of dw/dw with cycloheximide does not prevent induction of PRL receptors by bGH injections. These observations indicate that bGH induces the PRL receptor by interacting with the cell at some point distal to the induced receptor site and does not require the synthesis of new proteins.
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Enanismo/genética , Hormona del Crecimiento/farmacología , Hígado/metabolismo , Prolactina/metabolismo , Receptores de Superficie Celular/biosíntesis , Animales , Membrana Celular/metabolismo , Electroforesis en Gel de Poliacrilamida , Femenino , Hígado/efectos de los fármacos , Masculino , RatonesRESUMEN
The present study examined the way in which an indirect partial deafferentation of the medial portion of the ventrobasal complex (VPM/VPL) induced by neonatal transection of the infraorbital nerve (ION) altered the structural and functional properties of its constituent neurons. This manipulation significantly reduced the volume of the contralateral VPM/VPL. In addition, cell counts in Nissl-stained material revealed a significant reduction of the number of VPM/VPL neurons contralateral to neonatal ION transection. We also analyzed the effect of neonatal ION transection on the soma-dendritic morphology of individual neurons in the ventral posteromedial nucleus of the thalamus (VPM) by intracellular injection of horseradish peroxidase (HRP) in vivo and Lucifer yellow in fixed slices. Neonatal transection of the ION resulted in increased dendritic length, area, and volume of VPM neurons in both preparations; however only the changes observed in fixed slices reached statistical significance. Alterations in the functional characteristics of VPM neurons were also observed following neonatal nerve damage. There was a significant decrease in the percentage of vibrissae-sensitive neurons and a corresponding increase in the percentages of neurons responsive to guard hair deflection or that were unresponsive to peripheral stimulation. Neonatal nerve damage also resulted in significantly longer latencies of VPM cells after stimulation of either trigeminal nucleus principalis or subnucleus interpolaris. The present results indicate that the development of normal response properties and soma-dendritic morphology of VPM neurons is dependent upon intact afferent input during development. Indirect partial deafferentation of VPM/VPL by neonatal transection of the ION results in reduced neuron number, which may result in decreased competition among the dendrites of these neurons. This proposal is consistent with observations of increased dendritic dimensions of VPM neurons contralateral to neonatal ION damage.
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Órbita/inervación , Núcleos Talámicos/crecimiento & desarrollo , Animales , Animales Recién Nacidos , Recuento de Células , Desnervación , Estimulación Eléctrica , Colorantes Fluorescentes , Peroxidasa de Rábano Silvestre , Isoquinolinas , Fenómenos Fisiológicos del Sistema Nervioso , Neuronas/citología , Neuronas/ultraestructura , Ratas , Tiempo de Reacción , Núcleos Talámicos/citologíaRESUMEN
We have tested a set of oligonucleotide primers originally developed for the specific amplification of 16S rRNA gene segments from cyanobacteria, in order to determine their versatility as an identification tool for phototrophic eucaryotes. Using web-based bioinformatics tools we determined that these primers not only targeted cyanobacterium sequences as previously described, but also 87% of sequences derived from phototrophic eucaryotes. In order to qualify our finding, a type culture and environmental strain from the freshwater unicellular, green algae genus Chlorella Beijerinck, were selected for further study. Subsequently, we sequenced a 578-bp fragment of the 16S rRNA gene, which proved to be present within the chloroplast genome, performed sequence analysis and positively identified our solvent-degrading environmental strain (SDC1) as Chlorella vulgaris.
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Chlorella/clasificación , ADN de Hongos/genética , ARN Ribosómico 16S/genética , Chlorella/genética , Cloroplastos/genética , Clonación Molecular , Biología Computacional , Cartilla de ADN , Agua Dulce/microbiología , Datos de Secuencia Molecular , Alineación de Secuencia , Homología de Secuencia de Ácido NucleicoRESUMEN
Cyanobacteria are an ancient and diverse group of photosynthetic microorganisms, which inhabit many different and extreme environments. This indicates a high degree of biological adaptation, which has enabled these organisms to thrive and compete effectively in nature. The filamentous cyanobacterium, Lyngbya majuscula, produces several promising antifungal and cytotoxic agents, including laxaphycin A and B and curacin A. Samples of L. majuscula collected from Moorea Island, Tahiti (French Polynesia) and from the Culture Collection of Algae and Protozoa (CCAP 1446/4) were studied and adapted to large scale laboratory culture (5 l). This constitutes a 100-fold scale-up for the culture of this particular strain of L. majuscula. The effect of culture vessel configurations, growth conditions and media compositions on growth of L. majuscula was examined. Using optimised culture conditions, two strains of L. majuscula are currently being evaluated for their production of secondary metabolites. Results will be compared with those obtained from four environmental extracts. Comparisons were made by thin layer chromatography (TLC), high performance liquid chromatography (HPLC) and fourier transform ion cyclotron resonance mass spectrometry (FTICR-MS). It was shown that varying the culture conditions under which L. majuscula was grown had the greatest effect on secondary metabolite production, thus providing potential for future bioprocess intensified production.
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Cianobacterias/metabolismo , Lipoproteínas/análisis , Microbiología del Agua , Cromatografía Líquida de Alta Presión , Cromatografía en Capa Delgada , Medios de Cultivo , Espectrometría de MasasRESUMEN
The purpose of this paper is to discuss general treatment guidelines for treating patients with acute burns and to review pathophysiology of acute burn injuries. I will discuss skin composition briefly, give a review of acute burn pathophysiology and medical treatment, outline the psychological factors physical therapists should consider when working with these patients, and discuss physical therapy for the patient with acute burns. Physical therapy for patients with burns has become a specialty as knowledge of burn injuries increases. I have attempted to review physical therapy burn knowledge for inexperienced clinicians beginning to treat patients with acute burns.
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Quemaduras/rehabilitación , Modalidades de Fisioterapia/métodos , Enfermedad Aguda , Adulto , Vendajes , Apósitos Biológicos , Quemaduras/fisiopatología , Quemaduras/terapia , Quemaduras por Inhalación/terapia , Niño , Fármacos Dermatológicos/uso terapéutico , Terapia por Ejercicio/métodos , Fluidoterapia , Humanos , Necesidades Nutricionales , Educación del Paciente como Asunto , Apoyo Social , Cuidado Terminal , Infección de Heridas/terapiaRESUMEN
The aerobic biodegradation of high liquid phase concentrations of 2-propanol (IPA) by a previously enriched solvent-tolerant bacterial consortium within a 1.9 l fed-batch three phase fixed bed bioreactor was investigated. Solvent concentrations of up to 7.9 g l(-1) were investigated. Previously enriched solvent-tolerant bacterial cells were immobilised onto porous glass cylinders as a means obioprocess intensification. Bioreactor start-up and acclimation was studied anacetone concentration tracked as an indicator of IPA utilization, as the sole carbon source within a minimal salts medium (MSM). The initial batch treatment of IPA exhibited a biodegradation rate of 0.11 g l(-1) h(-1) prior to biofilm formation Biofilm growth during the second batch treatment was consistent with an increase in metabolic activity and an IPA biodegradation rate of 0.34 g l(-1), followed by a reduction of biodegradation rate to a constant value of 0.078 g l(-1) h(-1) after 650 h. A maximum acetone generation rate of 1.3 g l(-1) h(-1) was obtained during the fourth IPA addition although the maximum acetone biodegradation rate of 0.38 g l(-1) h(-1) was observed during the initial IPA addition. It is proposed that the metabolic lag resulting from switching from alcohol dehydrogenase to acetone carboxylase is a major rate-limiting step in the deep oxidation of IPA to acetone. The results demonstrate the potential of a previously enriched solvent-tolerant bacterial consortium in fixed bed bioreactor systems, for the aerobic treatment of concentrated solvent-containing wastestreams.
Asunto(s)
2-Propanol/metabolismo , Bacterias Aerobias/fisiología , Biopelículas , Solventes/metabolismo , Purificación del Agua/métodos , Acetona/metabolismo , Biodegradación Ambiental , Cinética , Eliminación de Residuos Líquidos/métodosRESUMEN
The aerobic biological oxidation of 2-propanol (isopropyl alcohol, IPA) at extremely high concentrations in air by an enriched solvent-tolerant microbial consortium operating at ambient temperature was evaluated for six months. Solvent-tolerant microbial cells were immobilised onto porous glass pall rings and fed with either IPA or its metabolic product acetone as sole carbon source. Successful biofiltration of solvent vapour at a concentration of 24 g m(-3) was achieved with oxidation of up to 100% total inlet carbon. The maximum IPA mass loading and IPA elimination capacity (EC) was 1700 g m(-3) h(-1). This performance exceeds all previous values published in the literature for similar processes. A slip feed experiment, using acetone, was also performed in order to assess the substrate specificity performance. The biofilter responded successfully to a switch from acetone to IPA as sole carbon source, displaying little reduction in overall organic carbon removal.
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2-Propanol/metabolismo , Biopelículas , Reactores Biológicos , Solventes/metabolismo , Purificación del Agua/métodos , Bacterias Aerobias/metabolismo , HumanosRESUMEN
Proteomics is very much a technology-driven field. The ambition is to identify, quantify and to assess the state of posttranslational modification and interaction partners for every protein in the cell. The proteome is in a state of flux and is thus extremely complex. Analysis of the proteome is exacerbated by the huge dynamic concentration range of proteins in the cellular environment. The impact that mass spectrometry-based proteomics has had on the field of biology has heavily depended on dramatic improvements in mass spectrometry that have been made in recent years. We examined 1541 reports indexed in PubMed relating to proteomics and reproduction to identify trends in the field and to make some broad observations for future work. To set the scene, in the first part of the report, we give a comprehensive overview of proteomics and associated techniques and technologies (such as separations and mass spectrometry). The second part examines the field in light of these techniques and suggests some opportunities for application of these tools in the area of reproduction.
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Proteómica/tendencias , Reproducción/fisiología , Animales , Femenino , Humanos , Masculino , Espectrometría de Masas , Embarazo , Procesamiento Proteico-Postraduccional , Proteínas/análisis , Proteómica/métodos , Biología de SistemasAsunto(s)
Eritrocitos/enzimología , Hiperargininemia , Animales , Arginasa/sangre , Aromatizantes , OvinosAsunto(s)
Especies en Peligro de Extinción , Extinción Biológica , Lemur , Animales , Madagascar , Masculino , RiesgoRESUMEN
Globally, priority areas for biodiversity are relatively well known, yet few detailed plans exist to direct conservation action within them, despite urgent need. Madagascar, like other globally recognized biodiversity hot spots, has complex spatial patterns of endemism that differ among taxonomic groups, creating challenges for the selection of within-country priorities. We show, in an analysis of wide taxonomic and geographic breadth and high spatial resolution, that multitaxonomic rather than single-taxon approaches are critical for identifying areas likely to promote the persistence of most species. Our conservation prioritization, facilitated by newly available techniques, identifies optimal expansion sites for the Madagascar government's current goal of tripling the land area under protection. Our findings further suggest that high-resolution multitaxonomic approaches to prioritization may be necessary to ensure protection for biodiversity in other global hot spots.
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Anuros , Biodiversidad , Conservación de los Recursos Naturales , Insectos , Lemur , Lagartos , Plantas , Algoritmos , Animales , Conservación de los Recursos Naturales/métodos , Ecosistema , Geografía , Madagascar , ÁrbolesRESUMEN
Metabolic flux analysis using 13C-tracer experiments is an important tool in metabolic engineering since intracellular fluxes are non-measurable quantities in vivo. Current metabolic flux analysis approaches are fully based on stoichiometric constraints and carbon atom balances, where the over-determined system is iteratively solved by a parameter estimation approach. However, the unavoidable measurement noises involved in the fractional enrichment data obtained by 13C-enrichment experiment and the possible existence of unknown pathways prevent a simple parameter estimation method for intracellular flux quantification. The MCMC (Markov chain-Monte Carlo) method, which obtains intracellular flux distributions through delicately constructed Markov chains, is shown to be an effective approach for deep understanding of the intracellular metabolic network. Its application is illustrated through the simulation of an example metabolic network.
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Isótopos de Carbono/metabolismo , Cadenas de Markov , Método de Montecarlo , Matemática , Modelos TeóricosRESUMEN
Findings are presented from a 9-week field study on Aotus trivirgatus in continuous primary, tropical forest in Peru. One group of 2 adults and 2 juveniles utilized the same lodge area in the center of a home range of 3.1 ha for the duration of the study. The group utilized eleven fruit trees of nine different species during the 9 weeks. The home range overlapped extensively with that of other Aotus groups.
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Agresión , Conducta Agonística , Aotus trivirgatus , Conducta Animal , Haplorrinos , Fenómenos de Retorno al Lugar Habitual , Animales , Conducta Excretoria Animal , Conducta Alimentaria , Femenino , Humanos , Locomoción , Masculino , PerúRESUMEN
The last decade's lemur research includes successes in discovering new living and extinct species and learning about the distribution, biogeography, physiology, behavior, and ecology of previously little-studied species. In addition, in both the dry forest and rain forest, long-term studies of lemur demography, life history, and reproduction, have been completed in conjunction with data on tree productivity, phenology, and climate. Lemurs contrast with anthropoids in several behavioral features, including female dominance, targeted female-female aggression, lack of sexual dimorphism regardless of mating system, sperm competition coupled with male-male aggression, high infant mortality, cathemerality, and strict seasonal breeding. Hypotheses to explain these traits include the "energy conservation hypothesis" (ECH) suggesting that harsh and unpredictable climate factors on the island of Madagascar have affected the evolution of female dominance, and the "evolutionary disequilibrium hypotheses" (EVDH) suggesting that the recent megafauna extinctions have influenced lemurs to become diurnal. These hypotheses are compared and contrasted in light of recent empirical data on climate, subfossils, and lemur behavior. New data on life histories of the rain forest lemurs at Ranomafana National Park give further support to the ECH. Birth seasons are synchronized within each species, but there is a 6-month distribution of births among species. Gestation and lactation lengths vary among sympatric lemurs, but all lemur species in the rain forest wean in synchrony at the season most likely to have abundant resources. Across-species weaning synchrony seen in Ranomafana corroborates data from the dry forest that late lactation and weaning is the life history event that is the primary focus of the annual schedule. Lemur adaptations may assure maximum offspring survival in this environment with an unpredictable food supply and heavy predation. In conclusion, a more comprehensive energy frugality hypothesis (EFH) is proposed, which postulates that the majority of lemur traits are either adaptations to conserve energy (e.g., low basal metabolic rate (BMR), torpor, sperm competition, small group size, seasonal breeding) or to maximize use of scarce resources (e.g., cathemerality, territoriality, female dominance, fibrous diet, weaning synchrony). Among primates, the isolated adaptive radiation of lemurs on Madagascar may have been uniquely characterized by selection toward efficiency to cope with the harsh and unpredictable island environment.
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Conducta Animal , Lemur , Conducta Social , Adaptación Fisiológica , Animales , Antropología Física , Evolución Biológica , Dieta , Ecología , Metabolismo Energético , Femenino , Fósiles , Geografía , Madagascar , Masculino , Reproducción , Estaciones del AñoRESUMEN
Many extant species are at risk to go extinct. This impending loss of species is likely to cause changes in future ecosystem functions. Ecological components of diversity, such as dietary or habitat specializations, can be used to estimate the impact of extinctions on ecosystem functions. As an approach to estimate the impact of future extinctions, we tested interdependency between ecological and taxonomic change based on current predictions of extinction rates in primates. We analyzed the ecological characteristics of extant primate faunas having species in various categories of endangerment of extinction and forecasted the future primate faunas as if they were paleontological faunas. Predicting future faunas combines the wealth of ecological information on living primates with large, fossil record-like changes in diversity. Predicted extinction patterns of living primates in Africa, Asia, Madagascar, and South America show that changes in ecology differ among the regions in ways that are not reducible to taxonomic measures. The ecological effects of primate extinctions are initially least severe in South America and larger in Asia and Africa. Disproportionately larger ecological changes are projected for Madagascar. The use of taxonomy as a proxy for ecology can mislead when estimating competence of future primate ecosystems.
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Evolución Biológica , Primates , Animales , Clasificación , Ecosistema , Fósiles , PaleontologíaRESUMEN
In Britain, Canada and the USA, a chronic shortage of registered nurses has existed since World War II. This situation is predicted to become worse. Reviews both the general and nursing literature in human resource planning, and recommends a system which can be build up step by step and individualized for each nursing department. The core planning activities are a planning database, demand forecasting, supply forecasting, variance analysis and forecasting, and recruitment policies.