Nazca Booby (Sula granti) inputs maintain the terrestrial food web of Malpelo Island

Most of the known food webs are based on organic compounds provided by photoautotrophic organisms. The terrestrial ecosystem of Malpelo Island (Colombia) seems to be an exception, however, since it supports several trophic guilds without hosting an adequate amount of primary producers. It has been suggested that this apparent paradox might be explained by external inputs provided by seabirds, namely Nazca Boobies (Sula granti), forming a huge colony on Malpelo. This hypothesis has never been tested. Here, we present a first approach to quantify the significance of Nazca Booby inputs into the Malpelo ecosystem via excrement, second eggs/chicks (which are prone to die), and carcasses, respectively, during the major breeding season. The total input was calculated to amount to 171.6 t per breeding season, with excrements accounting for almost 99% (170 t) of this input. Second eggs/chicks contributed approximately 1.1 t (0.64%) and carcasses around 0.1 t (0.06%). These finding support the idea of the Nazca Booby facilitating a food chain that pairs the pelagic primary producers of the open ocean with the terrestrial consumers of an island. Species most strongly profiting from this process include three endemic lizard species (Anolis agassizi, Diploglossus millepunctatus, Phyllodactylus transversalis) and the land crab (Johngarthia malpilensis).     

Genetic and physical characterisation of the locus controlling columnar habit in apple (Malus × domestica Borkh.)

A better understanding of the genetic control of tree architecture would potentially allow improved tailoring of newly bred apple cultivars in terms of field management aspects, such as planting density, pruning, pest control and disease protection. It would also have an indirect impact on yield and fruit quality. The Columnar (Co) locus strongly suppresses lateral branch elongation and is the most important genetic locus influencing tree architecture in apple. Co has previously been mapped on apple linkage group (LG) 10. In order to obtain fine mapping of Co, both genetically and physically, we have phenotypically analysed and screened three adult segregating experimental populations, with a total of 301 F₁ plants, and one substantial 3-year old population of 1,250 F₁ plants with newly developed simple sequence repeat (SSR) markers, based on the ‘Golden delicious’ apple genome sequence now available. Co was found to co-segregate with SSR marker Co04R12 and was confined in a region of 0.56 cM between SSR markers Co04R11 and Co04R13, corresponding to 393 kb on the ‘Golden delicious’ genome sequence. In this region, 36 genes were predicted, including at least seven sequences potentially belonging to genes that could be considered candidates for involvement in control of shoot development. Our results provide highly reliable, virtually co-segregating markers that will facilitate apple breeding aimed at modifications of the tree habit and lay the foundations for the cloning of Co.     

Geochemistry and Microbial Populations in Sediments of the Northern Baffin Bay,Arctic

The Northern Baffin Bay between Greenland and Canada is a remote Arctic area restricted in primary production by seasonal ice cover, with presumably low sedimentation rates, carbon content and microbial activities in its sediments. Our aim was to study the so far unknown subseafloor geochemistry and microbial populations driving seafloor ecosystems. Shelf sediments had the highest organic carbon content, numbers of Bacteria and Archaea, and microcosms inoculated from Shelf sediments showed highest sulfate reduction and methane production rates. Sediments in the central deep area and on the southern slope contained less organic carbon and overall lower microbial numbers. Similar 16S rRNA gene copy numbers of Archaea and Bacteria were found for the majority of the sites investigated. Sulfate in pore water correlated with dsrA copy numbers of sulfate-reducing prokaryotes and differed between sites. No methane was found as free gas in the sediments, and mcrA copy numbers of methanogenic Archaea were low. Methanogenic and sulfate-reducing cultures were enriched on a variety of substrates including hydrocarbons. In summary, the Greenlandic shelf sediments contain vital microbial communities adapted to their specific environmental conditions.     

Buchbesprechung (Book Review)

Die Bedeutung insektenpathogener Viren als “Biologische Pflanzenschutzmittel” im System des Integrierten Pflanzenschutzes wird erläutert. Es wird dabei insbesondere auf die “Lückenindikationen” in Kulturpflanzenarten mit geringem Anbauumfang hingewiesen. Zu ihnen werden u.a. Gemüse, Zierpflanzen, Sonderkulturen wie Hopfen, Tabak und Wein, aber auch der Obstbau, gerechnet; daneben gehören aber auch Heil‐und Gewürzpflanzen sowie Rohstoffe für Diät‐und Säuglingsnahrungsmittel dazu. Schließlich wird der Forstschutz als ein wichtiges Refugium für die Anwendung biologischer Pflanzenschutzmittel im allgemeinen und damit auch für insektenpathogene Viren angesehen.

Einen hohen Stellenwert besitzen Unter‐Glas‐Kulturen, da hier biologische Bekämpfungsverfahren schon in einem erheblichen Umfang zur Anwendung kommen.

Die nachfolgenden Beispiele sollen stellvertretend für einen erfolgreichen Einsatz insektenpathogener Viren stehen:

• Bekämpfung von Spodoptera exigua in Chrysanthemenbeständen unter Glas in den Niederlanden mit dem autochthonen Virus und von Mamestra brassicae mit dem spezifischen Kernpolyeder‐Virus in Gewächshauskulturen von Rosen und Paprika (Wirkungsgrad 80 bis 100%) sowie an Kohl im Freiland (Wirkungsgrad 68, 9 bis 100%) in Deutschland.

• Das Granulose‐Virus der Wintersaateule (Agrotis segetum) ergab bei Anwendung gegen den Schädling an Astern Mortalitätswerte zwischen 90, 5 und 94, 1%.

In allen Versuchen erwiesen sich die Viren den als Standard mitgeführten chemischen Insektiziden als gleichwertig.

Am Zusammenbruch lokaler Gradationen der Kiefernbuschhornblattwespe Diprion similis in verschiedenen deutschen Bundesländern (Sachsen‐Anhalt, Sachsen) war ein spezifisches Kernpolyeder‐Virus wesentlich mitbeteiligt.     

Liposomes and Liposome-like Vesicles for Drug and DNA Delivery to Mitochondria

Mitochondrial research is presently one of the fastest growing disciplines in biomedicine. Since the early 1990s, it has become increasingly evident that mitochondrial dysfunction contributes to a large variety of human disorders, ranging from neurodegenerative and neuromuscular diseases, obesity, and diabetes to ischemia-reperfusion injury and cancer. Most remarkably, mitochondria, the “power house” of the cell, have also become accepted as the “motor of cell death” reflecting their recognized key role during apoptosis. Based on these recent exciting developments in mitochondrial research, increasing pharmacological efforts have been made leading to the emergence of “Mitochondrial Medicine” as a whole new field of biomedical research. The identification of molecular mitochondrial drug targets in combination with the development of methods for selectively delivering biologically active molecules to the site of mitochondria will eventually launch a multitude of new therapies for the treatment of mitochondria-related diseases, which are based either on the selective protection, repair, or eradication of cells. Yet, while tremendous efforts are being undertaken to identify new mitochondrial drugs and drug targets, the development of mitochondria-specific drug carrier systems is lagging behind. To ensure a high efficiency of current and future mitochondrial therapeutics, colloidal vectors, i.e., delivery systems, need to be developed able to selectively transport biologically active molecules to and into mitochondria within living human cells. Here we review ongoing efforts in our laboratory directed toward the development of different phospholipid- and non-phospholipid-based mitochondriotropic drug carrier systems.     

Impact of vCJD on blood supply.

Variant Creutzfeldt-Jakob disease (vCJD) is an at present inevitably lethal neurodegenerative disease which can only be diagnosed definitely post mortem. The majority of the approximately 200 victims to date have resided in the UK where most contaminated beef materials entered the food chain. Three cases in the UK demonstrated that vCJD can be transmitted by blood transfusion. Since BSE and vCJD have spread to several countries outside the UK, it appears advisable that specific risk assessments be carried out in different countries and geographic areas. This review explains the approach adopted by Germany in assessing the risk and considering precautionary measures. A fundamental premise is that the feeding chain of cattle and the food chain have been successfully and permanently cleared from contaminated material. This raises the question of whether transmissions via blood transfusions could have the potential to perpetuate vCJD in mankind. A model calculation based on actual population data showed, however, that this would not be the case. Moreover, an exclusion of transfusion recipients from blood donation would add very little to the safety of blood transfusions, but would have a considerable impact on blood supply. Therefore, an exclusion of transfusion recipients was not recommended in Germany.     

Identification of (η6-arene)ruthenium(II) protein binding sites in E. coli cells by combined multidimensional liquid chromatography and ESI tandem mass spectrometry: specific binding of [(η6- p -cymene)RuCl2(DMSO)] to stress-regulated proteins and to helicases

An automated multidimensional protein identification technology, which combines biphasic liquid chromatography with electrospray ionisation tandem mass spectrometry (MS/MS), was employed to analyse tryptic peptides from Escherichia coli cells treated with the antiproliferation agent [(η⁶-p-cymene)RuCl₂(DMSO)], where DMSO is dimethyl sulfoxide. MS/MS spectra were recorded for molecular ions generated by neutral loss of p-cymene from intensive peptide ions coordinated by the (η⁶-p-cymene)Ru^II fragment. Matching of the MS/MS spectra of the ruthenated peptides to spectra of proteins in the E. coli database enabled the identification of five protein targets for [(η⁶-p-cymene)RuCl₂(DMSO)]. One of these is the constitutive cold-shock protein cspC, which regulates the expression of genes encoding stress-response proteins, and three of the other targets, ppiD, osmY and sucC, are proteins of the latter type. The DNA damage-inducible helicase dinG was likewise established as a protein target. Aspartate carboxylate functions were identified as the probable Ru binding sites in cspC, ppiD and dinG, and threonine and lysine side chains in osmY and sucC, respectively. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Solitary Song and its inhibition in some Estrildidae

Summary In the species studied song appears to have two functions; an epigamic function = Display Song, and a contact function = Solitary Song. Solitary Song appears to be common to all the species studied. Its utterance indicates that the bird is unpaired or separated from another individual with which it has formed a bond. InUraeginthus bengalus, U. angolensis, andAmandava amandava Solitary Song is also uttered by the hen in similar circumstances. InLonchura punctulata, A. amandava, andEuodice malabarica song is usually but not completely inhibited by the presence of a mate, in whose absence Solitary Song will be uttered even when other individuals of the same species are present. In the species studied of the generaEstrilda, Lagonosticta, andUraeginthus Solitary Song is inhibited by the continued close proximity of another bird even though this may be of the same sex or of a different species and may elicit aggressive or fleeing reactions; but conditions of close association with a bird other than a suitable mate would presumably only occur under captive conditions. There appears to be a distance factor controlling such inhibition. There is evidence of the inhibition of song due to the presence of a mate in other passerine species.     

The Effects of Spatial Scale on Trophic Interactions

Food chain models have dominated empirical studies of trophic interactions in the past decades, and have lead to important insights into the factors that control ecological communities. Despite the importance of food chain models in instigating ecological investigations, many empirical studies still show a strong deviation from the dynamics that food chain models predict. We present a theoretical framework that explains some of the discrepancies by showing that trophic interactions are likely to be strongly influenced by the spatial configuration of consumers and their resources. Differences in the spatial scale at which consumers and their resources function lead to uncoupling of the population dynamics of the interacting species, and may explain overexploitation and depletion of resource populations. We discuss how changed land use, likely the most prominent future stress on natural systems, may affect food web dynamics by interfering with the scale of interaction between consumers and their resource.