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In der Betriebs- und Volkswirtschaftslehre muss regelmäßig die Qualität von Prognosen beurteilt werden. Meist wird dabei nur eine prognostizierte Variable berücksichtigt. Das ist aber unzureichend, wenn mehrere Größen zugleich vorhergesagt werden. Als wichtige Anwendung können Konjunkturprognosen gelten, in denen mehrere Zielgrößen zu einem Zeitpunkt prognostiziert werden. Dieser Beitrag stellt Verfahren vor, mit denen ein Vektor aus verschiedenen Prognosen evaluiert werden kann und erläutert diese anhand eines Beispiels. Datengrundlage hierfür sind die jährlichen Prognosen des Sachverständigenrats und der (Herbst-)Gemeinschaftsdiagnose für die Veränderungsrate des realen Bruttoinlandsprodukts sowie die Inflationsrate, die Arbeitslosenquote und die Veränderungsraten der preisbereinigten Ex- und Importe für den Zeitraum 1993 bis 2020.

We rank the quality of German macroeconomic forecasts using various methods for 17 regular annual German economic forecasts from 14 different institutions for the period from 1993 to 2019. Using data for just one year, rankings based on different methods correlate only weakly with each other. Correlations of rankings calculated for two consecutive years and a given method are often relatively low and statistically insignificant. For the total sample, rank correlations between institutions are generally relatively high among different criteria. We report substantial long-run differences in forecasting quality, which are mostly due to distinct average forecast horizons. In the long-run, choosing the criterion to rank the forecasters is of minor importance. Rankings based on recession years and normal periods are similar. The same does hold for rankings based on real-time vs revised data.

The paper describes the “Halle Institute for Economic Research (IWH) Forecasting Dashboard (ForDas)”. This tool aims at providing, on a non-commercial basis, historical and actual macroeconomic forecast data for the Germany economy to researchers and interested audiences. The database renders it possible to directly compare forecast quality across selected institutions and over time. It is partly based on data collected in the DFG-funded project “Macroeconomic forecasts in great crisis”.

Class size reduction is frequently argued to be a cost-effective way to improve learner outcomes. In the South African context, most studies conclude that greater class sizes are associated with po...

In der Märzausgabe 2019 veröffentlichte der Wirtschaftsdienst einen Aufsatz mit dem Titel „Vorschlag zur Grundrente: ungerecht, ineffizient und teuer“ von Franz Ruland. Tim Köhler-Rama vertritt hier eine andere Auffassung, er plädiert für die Grundrente als Element des sozialen Ausgleichs im Rentenrecht. Im Anschluss erläutert Ruland seinen Standpunkt in einer Erwiderung.

Die staatliche Alterssicherung steht vor großen Herausforderungen. In den nächsten Jahren werden die geburtenstarken Jahrgänge ins Rentenalter eintreten. Dies wird die Kosten der Alterssicherung rapide ansteigen lassen. Zugleich werden zunehmend Jahrgänge ins Rentenalter kommen, die in ihren Biografien Phasen von Niedrigverdienst und Langzeitarbeitslosigkeit aufweisen. Das Thema Altersarmut wird vor diesem Hintergrund an Bedeutung zunehmen. Zugleich wird das Anfang der 2000er Jahre von der rotgrünen Regierung durchgesetzte neue "Drei-Säulen-Paradigma" in der Alterssicherung mehr und mehr unter Legitimationsdruck geraten, weil sich seine Ausgangslage verändert hat. Das Zinsniveau ist seit Jahren niedrig und die private Vorsorge hat insgesamt stark an Attraktivität eingebüßt. Dieses Buch bietet eine systematische Einführung in Grundfragen und Grundbegriffe der Alterssicherung. Es macht die überaus komplexe Thematik durchschaubar und kann dadurch zur Versachlichung der sozialstaatlichen Debatte in diesem Bereich beitragen. Für die 3. Auflage wurde es aktualisiert.

Terrestrial Trunked Radio (TETRA) is a worldwide common mobile communication standard, used by authorities and organizations with security tasks. Previous studies reported on health effects of TETRA, with focus on the specific pulse frequency of 17.64 Hz, which affects calcium efflux in neuronal cells. Likewise among others, it was reported that TETRA affects heart rate variability, neurophysiology and leads to headaches. In contrast, other studies conclude that TETRA does not affect calcium efflux of cells and has no effect on people's health. In the present study we examine whether TETRA short- and long-term exposure could affect the electrophysiology of neuronal in vitro networks. Experiments were performed with a carrier frequency of 395 MHz, a pulse frequency of 17.64 Hz and a differential quaternary phase-shift keying (π/4 DQPSK) modulation. Specific absorption rates (SAR) of 1.17 W/kg and 2.21 W/kg were applied. In conclusion, the present results do not indicate any effect of TETRA exposure on electrophysiology of neuronal in vitro networks, neither for short-term nor long-term exposure. This applies to the examined parameters spike rate, burst rate, burst duration and network synchrony.

Die Lohnersatzfunktion der gesetzlichen Rente macht die Bestimmung eines Sicherungsziels unerlasslich. Jahrzehntelang wurde das Sicherungsziel in der GRV daher sinnvollerweise mit einem Netto-Rentenniveau von 70 % verknupft. Seit den Rentenreformen 2001 / 2004 fehlt in der deutschen Alterssicherungspolitik fur die GRV ein sozialpolitisch begrundetes und empirisch fundiertes Sicherungsziel. Zugleich ignoriert die Politik, dass ein Zielkonflikt zwischen den beiden zentralen Zielen staatlicher Alterssicherungssysteme – Lohnersatz zur Statussicherung in der Nacherwerbsphase und Vermeidung von Altersarmut – existiert. Die Benennung einer imaginaren „Haltelinie“ fur das sinkende Rentenniveau stellt keine Losung dar, weil unklar ist, welchem Ziel die „Haltelinie“ eigentlich dienen soll. Why the Public Pension Scheme needs a Security Target Instead of ‘Stopping Lines’ Traditionally, the German old-age pension system was based on earnings replacement benefits with a well-founded target. Since the reform...

Die Transplantationsmedizin in Deutschland leidet unter einem permanenten Mangel an postmortal gespendeten Organen. Dieser Mangel hat sich insbesondere uber die letzten Jahre weiter verscharft. Als Ursache fur das Auseinanderfallen des Organangebots und der entsprechenden Nachfrage lassen sich sowohl strukturelle Probleme in den Entnahmekliniken, als auch eine mangelnde Bereitschaft der Bevolkerung zur Organspende anfuhren. Im Lichte dieser Problematik generiert die vorliegende, qualitativ-empirische (Pilot-)Studie Einsichten in Einstellungen und Meinungen zur Organspende. Auf der Grundlage von Beitragen aus Internet-Diskussionsforen und unter Anwendung der Methode GABEK® werden von der Bevolkerung vorgebrachte Argumente fur und gegen das postmortale Spenden von Organen extrahiert, analysiert und systematisch aufbereitet. Es kann gezeigt werden, dass insbesondere die Hirntoddiagnostik sowie der (un-)vollstandige Erhalt des Leichnams uberaus kontrovers diskutiert werden. Die Ergebnisse der (Pilot-)Studie ermoglichen es, Wissensdefizite und Fehlinformationen auf Seiten des Burgers aufzuzeigen und Anstose fur Informationskampagnen und (weitere) Aufklarung zu geben.

Nicole Gerlach,1,* Matthias Mentel,2,* Tim Köhler,2 Benjamin Tuchscherer,2 Birgit Garbe,1 Jasmina Ülker,1 Hagen Tronnier,1 Ulrike Heinrich,1 Mike Farwick2 1DermaTronnier GmbH & Co. KG, Institute for Experimental Dermatology, Witten/Herdecke University, Witten, 2Evonik Nutrition & Care GmbH, Essen, Germany *These authors contributed equally to this work Abstract: Sphingolipids are well known to promote keratinocyte differentiation and to induce ceramide production. In addition, they show anti-inflammatory and antimicrobial activities. Thus, the aim of this study is to investigate the potential effect of sphinganine on prolonging the hair anagen rate and improving the overall hair quality and scalp health. The inhibitory potential of sphinganine toward 5-α-reductase was studied using an in vitro assay. The stimulation of the antimicrobial peptide HBD2 by sphinganine was measured by real-time polymerase chain reaction and immunostaining. Sphinganine bioavailability was studied ex vivo using a pig skin model. A placebo-controlled, double-blind study was designed to evaluate the efficacy of sphinganine on hair loss and hair/scalp quality in vivo. In vitro results showed that sphinganine is a potent inhibitor of 5-α-reductase type I that prevents the conversion of testosterone to dihydrotestosterone, a key factor of androgenetic male baldness. In vivo results demonstrated efficacy in reducing non-illness-related hair loss among males. In terms of expert rating, all hair quality and scalp parameters improved after application of sphinganine. Improved scalp health might be linked to the observed increase of the antimicrobial peptide HBD2. Thus, sphinganine is well suited as a topical alternative for the improvement of scalp health and hair quality and anti-hair loss application. Keywords: sphinganine, 5-α-reductase inhibition, HBD2, hair loss, anagen rate, TrichoScan&reg

Termite gut flagellates are typically colonized by specific bacterial symbionts. Here we describe the phylogeny, ultrastructure and subcellular location of 'Candidatus Adiutrix intracellularis', an intracellular symbiont of Trichonympha collaris in the termite Zootermopsis nevadensis. It represents a novel, deep-branching clade of uncultured Deltaproteobacteria widely distributed in intestinal tracts of termites and cockroaches. Fluorescence in situ hybridization and transmission electron microscopy localized the endosymbiont near hydrogenosomes in the posterior part and near the ectosymbiont 'Candidatus Desulfovibrio trichonymphae' in the anterior part of the host cell. The draft genome of 'Ca. Adiutrix intracellularis' obtained from a metagenomic library revealed the presence of a complete gene set encoding the Wood-Ljungdahl pathway, including two homologs of fdhF encoding hydrogenase-linked formate dehydrogenases (FDHH ) and all other components of the recently described hydrogen-dependent carbon dioxide reductase (HDCR) complex, which substantiates previous claims that the symbiont is capable of reductive acetogenesis from CO2 and H2 . The close phylogenetic relationship between the HDCR components and their homologs in homoacetogenic Firmicutes and Spirochaetes suggests that the deltaproteobacterium acquired the capacity for homoacetogenesis via lateral gene transfer. The presence of genes for nitrogen fixation and the biosynthesis of amino acids and cofactors indicate the nutritional nature of the symbiosis.

Um die Leistungsabsenkungen im Rentensystem der drei vergangenen Jahrzehnte anschaulich zu machen, wird die tatsächliche Versicherungsbiografie seines Vaters mit der fiktiven identischen Versicherungsbiografie des Autors kontrastiert, der 28 Jahre später geboren wurde. Dabei zeigt sich, dass insbesondere die rentenrechtliche Entwertung von Ausbildungs- und Arbeitslosigkeitszeiten zu drastisch niedrigeren Rentenanwartschaften des Sohnes führen. Die 'Entsicherung' sozialer Risikolagen mit der Folge tatsächlicher Rentenabsenkungen spiegeln sich nicht in dem vieldiskutierten Rentenniveau wider. To illustrate the reductions in the benefits of the pension system over the past three decades, the actual insurance history of the author's father is contrasted with an identical, fictitious insurance history of the author, who was born 28 years later. This illustrates that the devaluation of periods of training and unemployment under pension law leads to drastically lower pension entitlements for the son. The actual pension reductions created by the lack of coverage of social risk situations is not reflected in the much discussed pension level.

Mixed infections of insect larvae with different baculoviruses are occasionally found. They are of interest from an evolutionary as well as from a practical point of view when baculoviruses are applied as biocontrol agents. Here, we report mixed-infection studies of neonate larvae of the common cutworm, Agrotis segetum , with two baculoviruses, Agrotis segetum nucleopolyhedrovirus B (AgseNPV-B) and Agrotis segetum granulovirus (AgseGV). By applying quantitative PCR (qPCR) analysis, coinfections of individual larvae were demonstrated, and occlusion body (OB) production within singly infected and coinfected larvae was determined in individual larvae. Mixtures of viruses did not lead to changes in mortality rates compared with rates of single-virus treatments, indicating an independent action within host larvae under our experimental conditions. AgseNPV-B-infected larvae showed an increase in OB production during 2 weeks of infection, whereas the number of AgseGV OBs did not change from the first week to the second week. Fewer OBs of both viruses were produced in coinfections than in singly infected larvae, suggesting a competition of the two viruses for larval resources. Hence, no functional or economic advantage could be inferred from larval mortality and OB production from mixed infections of A. segetum larvae with AgseNPV-B and AgseGV.

The Wickerhamomyces ciferrii strain NRRL Y-1031 F-60-10A is a well-known producer of tetraacetylphytosphingosine (TAPS) and used for the biotechnological production of sphingolipids and ceramides. It was our aim to gain new biological insights into the sphingolipid metabolism by employing a dual platform mass spectrometry strategy. The first step comprised metabolic 15N-labeling in combination with label-free proteomics using high resolution LTQ Orbitrap mass spectrometry. Then selected reaction monitoring tandem mass spectrometry served for the targeted quantification of sphingoid base biosynthesis enzymes. The non-producer strain NRRL Y-1031-27 served as a reference strain. In total, 1697 proteins were identified, and 123 enzymes of main metabolic pathways were observed as differentially expressed. Major findings were: 1) the likely presence of higher carbon flux in NRRL Y-1031 F-60-10A, resulting in higher availability of pyruvate and acetyl-CoA; 2) indications of oleaginous yeast-like behavior in NRRL Y-1031 F-60-10A; and 3) approx. 2-fold higher abundance of eight sphingolipid biosynthesis enzymes in NRRL Y-1031 F-60-10A. Taken together, in NRRL Y-1031 F-60-10A, the levels of glycolytic enzymes apparently gear carbon flux towards higher acetyl-CoA synthesis rates, while simultaneously reducing protein biosynthesis in the process. Thereby, C2 building blocks for acyl-moieties and downstream sphingoid base acetylation are provided to maintain TAPS production. Biological significance First quantitative proteome study for a phytosphingosine-producing yeast.

The Arabidopsis thaliana Qa-SNARE SYP121 (=SYR1/PEN1) drives vesicle traffic at the plasma membrane of cells throughout the vegetative plant. It facilitates responses to drought, to the water stress hormone abscisic acid, and to pathogen attack, and it is essential for recovery from so-called programmed stomatal closure. How SYP121-mediated traffic is regulated is largely unknown, although it is thought to depend on formation of a fusion-competent SNARE core complex with the cognate partners VAMP721 and SNAP33. Like SYP121, the Arabidopsis Sec1/Munc18 protein SEC11 (=KEULE) is expressed throughout the vegetative plant. We find that SEC11 binds directly with SYP121 both in vitro and in vivo to affect secretory traffic. Binding occurs through two distinct modes, one requiring only SEC11 and SYP121 and the second dependent on assembly of a complex with VAMP721 and SNAP33. SEC11 competes dynamically for SYP121 binding with SNAP33 and VAMP721, and this competition is predicated by SEC11 association with the N terminus of SYP121. These and additional data are consistent with a model in which SYP121-mediated vesicle fusion is regulated by an unusual “handshaking” mechanism of concerted SEC11 debinding and rebinding. They also implicate one or more factors that alter or disrupt SEC11 association with the SYP121 N terminus as an early step initiating SNARE complex formation.

Der Altenquotient steigt deutlich an, das Rentenniveau sinkt. Dies fordert politisches Handeln heraus. Noch in diesem Herbst will Sozialministerin Andrea Nahles Eckpunkte einer Reform der Alterssicherung vorstellen. Stellschrauben gibt es genug: Die betriebliche Altersvorsorge kann besser gesichert, die private Rentenversicherung ausgebaut, die Beitragsbasis in der gesetzlichen Rentenversicherung erweitert, das Renteneintrittsalter angehoben und staatliche Zuschüsse können erhöht werden. Die Autoren sind sich durchaus nicht darüber einig, wo der dringendste Handlungsbedarf besteht und ob nicht gar das ganze System zurückgedreht werden sollte. The demographic imbalance is aggravating, and by 2060 the old-age dependency ratio will double to approximately 70%. This development has consequences for the state pension system: growing contribution rates to social security coupled with lower pension levels, but at the same time a higher retirement age. The German pension scheme is mandatory for all wage and salary earners, but since 2001, no reasonable indicator for measuring the pension level exists any more. As a consequence of this, old-age pension has lost its traditional function as a replacement for earnings. The recent pension reforms have dropped the pension level sharply. Further reductions have been announced with the consequence of increasing old age poverty. Against this background it is proposed to raise the pension level so that the pensioners can maintain their standard of living. But any pension reform involves issues of distribution between and often also within generations, which cannot be addressed without explicit equity criteria. Some authors consider the past reforms as a mistake, others suggest adjustments.

Summary Termite gut flagellates are colonized by host-specific lineages of ectosymbiotic and endosymbiotic bacte- ria. Previous studies have shown that flagellates of the genus Trichonympha may harbour more than one type of symbiont. Using a comprehensive approach that combined cloning of SSU rRNA genes with fluo- rescence in situ hybridization and electron micros- copy, we investigated the phylogeny and subcellular locations of the symbionts in a variety of Trichonym- pha species from different termites. The flagellates in Trichonympha Cluster I were the only species asso- ciated with 'Endomicrobia', which were located in the posterior part of the cell, confirming previous results. Trichonympha species of Cluster II from the termite genus Incisitermes (family Kalotermitidae) lacked 'Endomicrobia' and were associated with endo- symbiotic Actinobacteria, which is highly unusual. The endosymbionts, for which we suggest the name 'Candidatus Ancillula trichonymphae', represent a novel, deep-branching lineage in the Micrococcineae that consists exclusively of clones from termite guts. They preferentially colonized the anterior part of the flagellate host and were highly abundant in all species of Trichonympha Cluster II except Tricho- nympha globulosa. Here, they were outnumbered by a Desulfovibrio species associated with the cytoplas- mic lamellae at the anterior cell pole. Such symbionts are present in both Trichonympha clusters, but not in all species. Unlike the intracellular location reported for the Desulfovibrio symbionts of Trichonympha agilis (Cluster I), the Desulfovibrio symbionts of T. globulosa (Cluster II) were situated in deep invagi- nations of the plasma membrane that were clearly connected to the exterior of the host cell.

To follow endocytosis in BY-2 cells we made use of fluorescent nano beads. Beads with 20nm in diameter were internalised rapidly and accumulated partially in compartments also labelled by the endocytic marker FM4-64. Studies in BY-2 cells and protoplasts revealed that larger beads (100nm) were excluded from uptake into turgescent and plasmolysed cells while protoplasts were able to internalise beads with a diameter of up to 1000nm. Endocytosis of beads was only partially inhibited by the clathrin-specific inhibitor Ikarugamycin and strongly blocked by wortmannin. These results imply that uptake of beads involves clathrin-dependent and clathrin-independent endocytic mechanisms and supports the hypothesis that clathrin-independent endocytosis plays a general role in plants.

The non-conventional yeast Pichia ciferrii is known to secrete the sphingoid long-chain base phytosphingosine in a tetraacetylated form (TAPS). Sphingolipids are important ingredients in cosmetic applications as they play important roles in human skin. Our work aimed to improve TAPS production by genetic engineering of P. ciferrii. In the first step we improved precursor availability by blocking degradation of L-serine, which is condensed with palmitoyl-CoA by serine palmitoyltransferase in the first committed step of sphingolipid biosynthesis. Successive deletion of two genes, SHM1 and SHM2, encoding L-serine hydroxymethyltransferases, and of CHA1 encoding L-serine deaminase, resulted in a strain producing 65 mg((TAPS))g(-1)((cdw)), which is a threefold increase in comparison with the parental strain. Attempts to increase the metabolic flux into and through the L-serine biosynthesis pathway did not improve TAPS production. However, genetic engineering of the sphingolipid pathway further increased secretion of TAPS. Blocking of sphingoid long-chain base phosphorylation by deletion of the LCB kinase gene PcLCB4 resulted in a further increase in TAPS production by 78% and significant secretion of the direct precursor of phytosphingosine, sphinganin, in a triacetylated form (TriASa). Overproduction of two serine palmitoyltransferase subunits, Lcb1 and Lcb2, together with a deletion of the gene ORM12 encoding a putative negative regulator of sphingolipid synthesis resulted in a strain producing 178 mg((TAPS))g(-1)((cdw)). Additional overproduction of the C4-hydroxylase Syr2 converting sphinganine to phytosphingosine reduced TriASa production and further improved TAPS production. The final recombinant P. ciferrii strain produced up to 199 mg((TAPS))g(-1)((cdw)) with a maximal production rate of 8.42 mg×OD(600nm)(-1)h(-1) and a titer of about 2 g L(-1), and should be applicable for industrial TAPS production.

Ein einheitlicher Rentenbeitrag trotz längerer Lebenserwartung der Frauen, der Ausbau derKindererziehungszeiten und die Hinterbliebenenrenten stellen faktische Begünstigungen von Frauen in der gesetzlichen Rentenversicherung dar. Wie sollten derartige Umverteilungen ordnungspolitisch korrekt finanziert werden? Während Kindererziehungs- und Hinterbliebenenleistungen (zumindest teilweise) aus Steuermitteln finanziert werden, gilt dies bislang nicht für den Transfer zugunsten der Frauen aufgrund von durchschnittlich längeren Rentenlaufzeiten. Die Autoren plädieren grundsätzlich für eine Mischfi nanzierung der Kosten.

It is well known that at the interface between neuronal tissue and recording electrode low electrical impedance is required. However, if simultaneous optical detection or stimulation is an issue, good optical transmittance of the electrode material is desirable as well. State-of-the-art titanium nitride electrodes provide superior low impedance compared to gold or iridium, but are nontransparent. Transparent electrode materials like the transparent conducting oxide, indium tin oxide (ITO), or graphene offer high light transmittance (>80%) but reveal relatively high impedance. In this paper, the authors propose the conducting polymer poly(3,4-ethylenedioxythiophene) with the counter ion NO3- as the electrode material for low impedance and good optical transmittance properties. The polymer is electrochemically deposited onto ITO improving the relatively high impedance of ITO. This multilayer electrode allows not only for electrophysiological recordings of cardiomyocytes but also for monitoring of cell contraction under the microscope. Electrochemical impedance spectroscopy and action potential recordings reveal that the new transparent electrodes are a good compromise in terms of low impedance and transparency if deposition parameters are optimized.

Zusammenfassung Die langfristige Absenkung des Leistungsniveaus in der gesetzlichen Rentenversicherung und die Anhebung der Altersgrenzen wirken sich auch auf die Erwerbsminderungsrenten aus. Dies stellt ein sozialpolitisches Problem dar, weil erwerbsgeminderte Personen Leistungseinschränkungen weder durch eine Verlängerung der Erwerbsphase noch - insbesondere bei einem Eintritt der Erwerbsminderung in jungen jähren - durch verstärkte private Vorsorge kompensieren können. Dieser Beitrag vergleicht vor diesem Hintergrund verschiedene Möglichkeiten zur Anhebung der Leistungen bei Erwerbsminderung im Hinblick auf ihre Einkommenswirkungen. Dabei zeigt sich, dass die Höherbewertung der so genannten Zurechnungszeit eine effiziente Maßnahme darstellt, weil auf diese Weise mit einem relativ geringen Kostenaufwand die Armutsgefährdung des betroffenen Personenkreises wirksam reduziert werden könnte.

Zusammenfassung Der Artikel thematisiert Zusammenhange zwischen konjunkturellen Entwicklungen und Funktionsweise der bundesdeutschen gesetzlichen Rentenversicherung (GRV). Hierbei stehen die konjunkturbezogenen Wirkungen der GRV-Budgetgleichung und der Rentenanpassungsformel im Mittelpunkt. Zusatzlich sind aber auch die Konsumneigungen der Rentnerinnen und Rentner in Deutschland angesichts der quantitativen volkswirtschaftlichen Bedeutung der GRV von Relevanz. Die entsprechenden Erorterungen sind vor dem Hintergrund der derzeitigen weltwirtschaftlichen Krise von aktuellem Interesse. In diesem Zusammenhang zeigen sich insbesondere die konjunkturstabilisierenden Wirkungen der (verzogerten) Rentenanpassung. The Business Cycle and the German Pension System This article examines the relationship between developments in the business cycle and the German retirement system. In particular, the focus here is on, firstly, the effects that the business cycle has on the calculations that are used to balance the budg...

The yeast Pichia ciferrii produces large quantities of the sphingoid base tetraacetyl phytosphingosine (TAPS) and is an interesting platform organism for the biotechnological production of sphingolipids and ceramides. Ceramides have attracted great attention as a specialty ingredient for moisture retention and protection of the skin in the cosmetics industry. First attempts have been started to metabolically engineer P. ciferrii for improved production of TAPS and other sphingoid bases. However, rational metabolic engineering of P. ciferrii is difficult due to a low gene targeting efficiency. In eukaryotes, two major pathways coexist, which are responsible for genomic DNA integration, homologous recombination (HR) and non-homologous end joining (NHEJ). Integration via HR is targeted, while NHEJ involves ectopic (non-targeted) integration depending on a ligation step mediated by DNA ligase IV (Lig4). Here, we demonstrate a dramatical increase in gene targeting efficiency in a P. ciferrii lig4 knockout strain, deficient in NHEJ. Furthermore, a quick and easy to use freeze-thaw method was developed to transform P. ciferrii with high efficiency. Owing to the ability of targeting genomic DNA integration our results pave the way for further genetic and metabolic engineering approaches with P. ciferrii by means of knocking out or overexpressing predestinated genes.

Termite gut flagellates are typically colonized by specific bacterial symbionts. Here we describe the phylogeny, ultrastructure and subcellular location of 'Candidatus Adiutrix intracellularis', an intracellular symbiont of Trichonympha collaris in the termite Zootermopsis nevadensis. It represents a novel, deep-branching clade of uncultured Deltaproteobacteria widely distributed in intestinal tracts of termites and cockroaches. Fluorescence in situ hybridization and transmission electron microscopy localized the endosymbiont near hydrogenosomes in the posterior part and near the ectosymbiont 'Candidatus Desulfovibrio trichonymphae' in the anterior part of the host cell. The draft genome of 'Ca. Adiutrix intracellularis' obtained from a metagenomic library revealed the presence of a complete gene set encoding the Wood-Ljungdahl pathway, including two homologs of fdhF encoding hydrogenase-linked formate dehydrogenases (FDHH ) and all other components of the recently described hydrogen-dependent carbon dioxide reductase (HDCR) complex, which substantiates previous claims that the symbiont is capable of reductive acetogenesis from CO2 and H2 . The close phylogenetic relationship between the HDCR components and their homologs in homoacetogenic Firmicutes and Spirochaetes suggests that the deltaproteobacterium acquired the capacity for homoacetogenesis via lateral gene transfer. The presence of genes for nitrogen fixation and the biosynthesis of amino acids and cofactors indicate the nutritional nature of the symbiosis.

Recent developments in sequencing technology have given rise to a large number of studies that assess bacterial diversity and community structure in termite and cockroach guts based on large amplicon libraries of 16S rRNA genes. Although these studies have revealed important ecological and evolutionary patterns in the gut microbiota, classification of the short sequence reads is limited by the taxonomic depth and resolution of the reference databases used in the respective studies. Here, we present a curated reference database for accurate taxonomic analysis of the bacterial gut microbiota of dictyopteran insects. The Dictyopteran gut microbiota reference Database (DictDb) is based on the Silva database but was significantly expanded by the addition of clones from 11 mostly unexplored termite and cockroach groups, which increased the inventory of bacterial sequences from dictyopteran guts by 26%. The taxonomic depth and resolution of DictDb was significantly improved by a general revision of the taxonomic guide tree for all important lineages, including a detailed phylogenetic analysis of the Treponema and Alistipes complexes, the Fibrobacteres, and the TG3 phylum. The performance of this first documented version of DictDb (v. 3.0) using the revised taxonomic guide tree in the classification of short-read libraries obtained from termites and cockroaches was highly superior to that of the current Silva and RDP databases. DictDb uses an informative nomenclature that is consistent with the literature also for clades of uncultured bacteria and provides an invaluable tool for anyone exploring the gut community structure of termites and cockroaches.

While the gut microbiota of termites and its role in symbiotic digestion have been studied for decades, little is known about the bacteria colonizing the intestinal tract of the distantly related wood-feeding cockroaches (Blaberidae: Panesthiinae). Here, we show that physicochemical gut conditions and microbial fermentation products in the gut of Panesthia angustipennis resemble that of other cockroaches. Microsensor measurements confirmed that all gut compartments were anoxic at the center and had a slightly acidic to neutral pH and a negative redox potential. While acetate dominated in all compartments, lactate and hydrogen accumulated only in the crop. The high, hydrogen-limited rates of methane emission from living cockroaches were in agreement with the restriction of F420-fluorescent methanogens to the hindgut. The gut microbiota of both P. angustipennis and Salganea esakii differed strongly between compartments, with the highest density and diversity in the hindgut, but similarities between homologous compartments of both cockroaches indicated a specificity of the microbiota for their respective habitats. While some lineages were most closely related to the gut microbiota of omnivorous cockroaches and wood- or litter-feeding termites, others have been encountered also in vertebrates, reinforcing the hypothesis that strong environmental selection drives community structure in the cockroach gut.

International audience; The gut microbiota of termites plays critical roles in the symbiotic digestion of lignocellulose. While phylogenetically lower termites' are characterized by a unique association with cellulolytic flagellates, higher termites (family Termitidae) harbour exclusively prokaryotic communities in their dilated hindguts. Unlike the more primitive termite families, which primarily feed on wood, they have adapted to a variety of lignocellulosic food sources in different stages of humification, ranging from sound wood to soil organic matter. In this study, we comparatively analysed representatives of different taxonomic lineages and feeding groups of higher termites to identify the major drivers of bacterial community structure in the termite gut, using amplicon libraries of 16S rRNA genes from 18 species of higher termites. In all analyses, the wood-feeding species were clearly separated from humus and soil feeders, irrespective of their taxonomic affiliation, offering compelling evidence that diet is the primary determinant of bacterial community structure. Within each diet group, however, gut communities of termites from the same subfamily were more similar than those of distantly related species. A highly resolved classification using a curated reference database revealed only few genus-level taxa whose distribution patterns indicated specificity for certain host lineages, limiting any possible cospeciation between the gut microbiota and host to short evolutionary timescales. Rather, the observed patterns in the host-specific distribution of the bacterial lineages in termite guts are best explained by diet-related differences in the availability of microhabitats and functional niches.

In Saccharomyces cerevisiae , the transcription factors Tec1p and Ste12p are required for haploid invasive and diploid pseudohyphal growth. Tec1p and Ste12p have been postulated to regulate these developmental processes primarily by cooperative binding to filamentous and invasion-responsive elements (FREs), which are combined enhancer elements that consist of a Tec1p-binding site (TCS) and an Ste12p-binding site (PRE). They are present in the promoter regions of target genes, e.g., FLO11 . Here, we show that Tec1p efficiently activates target gene expression and cellular development in the absence of Ste12p. We further demonstrate that TCS elements alone are sufficient to mediate Tec1p-driven gene expression by a mechanism termed TCS control that is operative even when Ste12p is absent. Mutational analysis of TEC1 revealed that TCS control, FLO11 expression, and haploid invasive growth require the C terminus of Tec1p. In contrast, the Ste12p-dependent FRE control mechanism is sufficiently executed by the N-terminal portion of Tec1p, which contains the TEA/ATTS DNA-binding domain. Our study suggests that regulation of haploid invasive and diploid pseudohyphal growth by Ste12p and Tec1p is not only executed by combinatorial control but involves additional control mechanisms in which Ste12p activates TEC1 expression via clustered PREs and where Tec1p regulates expression of target genes, e.g., FLO11 , by TCS control.

The 'matrikine' concept claims that processing of the precursors for collagen results in the formation of peptides such as KTTKS which in turn augments extracellular matrix (ECM) production. In the present study, we show the development of an anti-ageing active from an in silico approach by molecular design resulting in the tetrapeptide GEKG derived from ECM proteins. The efficacy of the peptide to significantly induce collagen production of the protein level and mRNA level has been demonstrated in vitro in human dermal fibroblasts and in vivo in a double-blind, randomized, placebo-controlled study enroling 10 volunteers with an average age of 48.2 years. The effect of GEKG on facial wrinkles was studied in 30 volunteers using state of the art fringe projection, which allows determination of surface roughness in three-dimensions. Here, only GEKG but not the placebo was able to significantly decrease skin roughness as a measure for wrinkles.

Termites digest wood and other lignocellulosic substrates with the help of their intestinal microbiota. While the functions of the symbionts in the digestive process are slowly emerging, the origin of the bacteria colonizing the hindgut bioreactor is entirely unknown. Recently, our group discovered numerous representatives of bacterial lineages specific to termite guts in a closely related omnivorous cockroach, but it remains unclear whether they derive from the microbiota of a common ancestor or were independently selected by the gut environment. Here, we studied the bacterial gut microbiota in 34 species of termites and cockroaches using pyrotag analysis of the 16S rRNA genes. Although the community structures differed greatly between the major host groups, with dramatic changes in the relative abundances of particular bacterial taxa, we found that the majority of sequence reads belonged to bacterial lineages that were shared among most host species. When mapped onto the host tree, the changes in community structure coincided with major events in termite evolution, such as acquisition and loss of cellulolytic protists and the ensuing dietary diversification. UniFrac analysis of the core microbiota of termites and cockroaches and construction of phylogenetic tree of individual genus level lineages revealed a general host signal, whereas the branching order often did not match the detailed phylogeny of the host. It remains unclear whether the lineages in question have been associated with the ancestral cockroach since the early Cretaceous (cospeciation) or are diet-specific lineages that were independently acquired from the environment (host selection).