Exploring respiration and respiratory electron transport system (ETS) in Ulva spp.

[ES] Respiration is a key ecological index. For either individuals or communities, it can be use to assess carbon and energy, demand and expenditure as well as carbon flow rates through food webs. When combined with productivity measurements it can establish the level of metabolic balance. When combined with measurements of respiratory capacity, it can indicate physiological state. Here, we report pilot studies the metabolism of the green algae, Ulva rotundata that inhabits intertidal pools of Gran Canaria. As a starting point we used the electron transport system (ETS) to differentiate between different growing conditions in the natural environment. We suspected different levels of stress associated with these conditions and looked for the influence of this stress in the ETS measurements. This technique has been successfully applied to study bacteria, phytoplankton and zooplankton in the ocean, but it has not been used to study sessile marine macroalgae. These neritic and littoral macrophytes have major ecological and industrial importance, yet little is known about their respiratory physiology. Such knowledge would strengthen our understanding of the resources of the coastal ocean and facilitate its development and best use. Here, we modified the ETS methodology for Ulva rotundata. With this modified ETS assay we investigated the capacity of Ulva to resist anoxia. We measured respiration with optodes (Fibox 4, Presens) in the dark to the point of oxygen exhaustion and through 24 h of anoxia. Then we exposed the Ulva to light and followed the oxygen increase due to photosynthesis. We discuss here the capacity of Ulva to survive during anoxia.

Relationship between respiration and Electron Transfer System (ETS) in zooplankton

<p>[EN]Respiration of zooplanktonic organisms is an significant fraction of the global carbon cycle. However, it estimation in order to obtain the data required in oceanography is still a problem. In this work, we studied respiration rates in laboratory and field experiments. Laboratory experiments using Daphnia spp. showed a significant decrease of respiration rates during starvation. In addition, we measured the gut fluorescence and enzymatic activity (electron transfer system, ETS). The former did not show the expected decrease probably due to the volume of the incubators. The relationship between respiration and ETS presented the classical variability ranging between 0.5 and 1 as observed in previous works. Copepod respiration rates were measured during RAPROCAN 1504 cruise around the Canary Islands.</p>

Relaciones entre biomasa, tasa de crecimiento, respiraci��n y respiraci��n potencial en el crust��ceo "Artemia salina"

Programa de Doctorado en Oceanograf��a

Metabolism and biomass vertical distribution of zooplankton in the Bransfield Strait during the austral summer of 2000

[EN] The vertical distribution (0?550 m) of zooplankton biomass, and indices of respiration (electron transfer system [ETS]) and structural growth (aminoacyltRNA synthetases activity [AARS]), were studied in waters off the Antarctic Peninsula during the austral summer of 2000. The dominant species were the copepod Metridia gerlachei and the euphausiid Euphausia superba. We observed a vertical krill/copepod substitution in the water column. The zooplankton biomass in the layer at a depth of 200?500 m was of the same magnitude as the biomass in the layer at a depth of 0?200 m, indicating that biomass in the mesopelagic zone is an important fraction of the total zooplankton in Antarctic waters. The metabolic rates of the zooplankton community were sustained by less than 0.5% of the primary production in the area, suggesting that microplankton or small copepods are the main food source. Neither food availability nor predation seemed to control mesozooplankton biomass. The wide time lag between the abundance peak of the dominant copepod (M. gerlachei) and the phytoplankton bloom is suggested to be the main explanation for the low summer zooplankton biomass observed in these waters.

Efecto de la inanici��n sobre el metabolismo respiratorio de los misid��ceos

[ES]Los misid��ceos son peque��os crust��ceos que se encuentran en muchas regiones costeras del mundo. Leptomysis lingvura se encuentra en la costa este de Gran Canaria (Espa��a) asociada a los fondos arenosos de profundidades entre 5 y 15 metros. Son un importante componente en la cadena tr��fica como alimento de muchos peces costeros y podr��an ser un potencial alimento para ser utilizado en acuicultura. Se ha estudiado su supervivencia y reproducci��n en cautividad para su utilizaci��n en estudios de laboratorio, y han resultado ser una especie apta que se adapta bien a las condiciones de cultivo. En el presente estudio se pretende dilucidar como influyen en la tasa respiratoria y en la tasa de respiraci��n potencial (actividad ETS) las condiciones fisiol��gicas en que se encuentran los organismos. Se han llevado a cabo dos experimentos, uno de ellos tiene como objetivo el estudio de organismos adultos de similar talla en diferentes per��odos de inanici��n para determinar su efecto en la respiraci��n y en la actividad ETS; el segundo experimento pretende determinar como influyen las condiciones de alimentaci��n en la relaci��n respiraci��n-biomasa. En el primer caso se observa un descenso de la tasa respiratoria en funci��n del aumento del per��odo de inanici��n, mientras que la respiraci��n potencial no muestra esta relaci��n, siendo m��s conservativa, lo que se da como resultado una disminuci��n del cociente R/ETS a medida que aumenta el per��odo de inanici��n. Tambi��n se observa un aumento de la tasa respiratoria al comienzo de la noche que puede tener relaci��n con ritmos circadianos end��genos de esta especie. El coeficiente de la relaci��n exponencial R-biomasa que presentan los organismos que fueron sometidos durante 7 d��as a condiciones l��mite de alimentaci��n son inferiores a 0.75 que establece la ley de Kleiber, mientras que los organismos en buenas condiciones de alimentaci��n muestran un coeficiente muy cercano o superior a 0.75.

Pyridine nucleotide levels in zooplankton: laboratory work and field samples

[ES]La respiraci��n es un proceso fisiol��gico com��n a todos los organismos marinos. En los estudios oceanogr��ficos se ha determinado, com��nmente, mediante la cuantificaci��n del consumo de ox��geno de organismos incubados en botellas. Esta metodolog��a es tediosa y lenta, por lo que Packard et al. (1971) propusieron el uso del an��lisis bioqu��mico basado en la actividad de las enzimas implicadas en la respiraci��n, el Sistema de Transporte de Electrones (ETS). Este an��lisis mide la velocidad m��xima que dichas enzimas pueden tener, determinando la respiraci��n potencial de los organismos. Dicha velocidad estar�� controlada por la disponibilidad intracelular de sus sustratos, los pirid��n nucle��tidos (NADH y NADPH). En el presente trabajo, se ha analizado el metabolismo respiratorio, a trav��s de medidas del ETS y de los pirid��n nucle��tidos, tanto en el dinoflagelado Oxyrrhis marina en estudios de laboratorio, como en organismos recogidos del medio marino durante la campa��a de circunnavegaci��n MALASPINA 2010

Behavior of respiratory metabolism and pyridine nucleotide levels in Oxyrrhis marina during starvation

M��ster en Oceanograf��a

Potential Respiration in Oxyrrhis marina and Rhodomonas salina

M��ster en Oceanograf��a

Zooplankton oxygen consumption and nutrient release in relation to species composition, animals size and enviromental conditions in the Baltic Sea during May and August

<p>[EN] Zooplankton metabolism in terms of oxygen consumption and &ntilde;utrient rel&eacute;ase (ammonia, phosphate) were measiu'ed in the Baltic Sea, a temp&eacute;rate &aacute;rea with high envirormiental changes both in space and in time. Plankton of the surface layer were analysed with balance measurements in 4 size classes between 50 and 1000 nm during spring in 1988, 1990 and 1991, in summer 19^8 and 1990 as well. The use of electr&oacute;n transport system (ETS), and the Glutamate Dehydrogenase (GDH) activity as indicators for respiration and ammonia rel&eacute;ase respectively, enlarged the data density and made a three dimensional resolution available (May 1990, 1991). Data are in the range of the latitudinal dependend magnitude. They reflect slight interannual, more seasonal and regional aspects. Anim&aacute;is size, temperature, food concentration, and species composition influence the specific rates</p>

Avances en ecofisiolog��a planct��nica y oceanograf��a bioqu��mica en la ULPGC

<p>[EN] This seminar will report the latest activities of the ULPGC��s Plankton Ecophysiology group (PEG). This group studies respiration, growth, nitrogen metabolism, oceanic carbon flux, deep ocean metabolism, and plankton cultivation. It works with zooplankton, phytoplankton, bacteria, and macroalgae. The premise behind the group��s investigations is that enzyme biochemistry controls an organism��s physiology that, in turn, has a strong impact on ocean chemistry and ecology. This research team (PEG) uses as foils, the metabolic theory of ecology (MTE) and Kleiber��s law to argue the fact that respiratory metabolism is controlled not by biomass, but by the respiratory electron transport system (R-ETS). It has pointed out that the reason, zooplankton respiration statistically correlates with biomass, is because biomass packages mitochondria and mitochondria package the R-ETS. It has demonstrated, experimentally with Artemia salina, the superiority of using ETS as a respiration proxy rather than using biomass. Working with bacteria it has shown the inadequacy of the MTE in describing respiration in different growth phases of bacteria and has shown that a rival model based on enzyme kinetics works much better.</p>

Bottle effects, toxicity and cell viability during incubation experiments to asses community respiration

M��ster en Oceanograf��a

A parallel future for Ocean research?

[EN] Today, science is difficult to pursue because funding is so tenuous. In such a financial climate, researchers need to consider parallel alternatives to ensure that scientific research can continue. Based on this thinking, we created BIOCEANSolutions, a company born of a research group. A great variety of environmental regulations and standards have emerged over recent years with the purpose of protecting natural ecosystems. These have enabled us to link our research to the market of environmental management. Marine activities can alter environmental conditions, resulting in changes in physiological states, species diversity, abundance, and biomass in the local biological communities. In this way, we can apply our knowledge, to plankton ecophysiology and biochemical oceanography. We measure enzyme activities as bio-indicators of energy metabolism and other physiological rates and biologic-oceanographic processes in marine organisms. This information provides insight into the health of marine communities, the stress levels of individual organisms, and potential anomalies that may be affecting them. In the process of verifying standards and complying with regulations, we can apply our analytic capability and knowledge. The main analyses that we offer are: (1) the activity of the electron transport system (ETS) or potential respiration (��), (2) the physiological measurement of respiration (oxygen consumption), (3) the activity of Isocitrate dehydrogenase (IDH), (4) the respiratory CO2 production, and (5) the activity of Glutamate dehydrogenase (GDH) and (6) the physiological measurement of ammonium excretion. In addition, our experience in a productive research group allows us to pursue and develop technical-experimental activities such as marine and freshwater aquaculture, oceanographic field sampling, as well as providing guidance, counseling, and academic services. In summary, this new company will permit us to create a symbiosis between public and private sectors that serve clients and will allow us to grow and expand as a research team.

Development of a fluorescent method for the detection in marine organisms of the respiratory electron transport system

Trabajo realizado por: Maldonado, F.; Packard, T.; G��mez, M.; Santana Rodr��guez, J. J

Respiratory electron transport activity in plankton: determinants and detection

<p>[ES]La presente tesis, se centra en el estudio del Sistema de Transporte de Electrones (ETS) en organismos del plancton marino, los factores que lo influencian la interpretaci��n de estas mediciones y su detecci��n mediante espectrofotometr��a y espectrofluorometr��a, en muestras oce��nicas naturales y en cultivos de organismos marinos. Se pudo establecer, la biomasa, la respiraci��n (R) y la respiraci��n potencial (��), en tres transectos en los oc��anos ��ndico y Atl��ntico Norte Sur. A su vez, se determino el estado fisiol��gico, en tres tama��os del zooplancton, midiendo la relaci��n R/��. Se explor�� los efectos de la inanici��n sobre la R y la variaci��n con respecto a la �� en el zooplancton</p>