Unravelling lactate-acetate and sugar conversion into butyrate by intestinal Anaerobutyricum and Anaerostipes species by comparative proteogenomics

Thed- andl-forms of lactate are important fermentation metabolites produced by intestinal bacteria but are found to negatively affect mucosal barrier function and human health. Both enantiomers of lactate can be converted with acetate into the presumed beneficial butyrate by a phylogenetically related group of anaerobes, includingAnaerobutyricumandAnaerostipesspp. This is a low energy yielding process with a partially unknown pathway inAnaerobutyricumandAnaerostipesspp. and hence, we sought to address this via a comparative genomics, proteomics and physiology approach. We compared growth ofAnaerobutyricum soehngeniion lactate with that on sucrose and sorbitol. Comparative proteomics revealed complete pathway of butyrate formation from sucrose, sorbitol and lactate. Notably, a gene cluster,lctABCDEFwas abundantly expressed when grown on lactate. This gene cluster encodes a lactate dehydrogenase (lctD), electron transport proteins A and B (lctCB), nickel-dependent racemase (lctE), lactate permease (lctF) and short-chain acyl-CoA dehydrogenase (lctG). Investigation of available genomes of intestinal bacteria revealed this new gene cluster to be highly conserved in onlyAnaerobutyricumandAnaerostipesspp. Present study demonstrates thatA. soehngeniiand several relatedAnaerobutyricumandAnaerostipesspp. are highly adapted for a lifestyle involving lactate plus acetate utilization in the human intestinal tract.Peer reviewe

Hypertrophic abductor hallucis muscle with nerve compression syndrome

A 13-year-old girl presented with a soft tissue swelling at the posteromedial side of the foot. This swelling had been present since birth but recently started to cause discomfort and radiating pain to the plantar aspect of the first and second toes. A magnetic resonance imaging (MRI) showed a soft tissue mass (2,6 x 3,7 x 13 centimetres) at the posteromedial side of the foot with signal-intensity similar to the intensity of muscle tissue on all the different sequences. There was no pathological contrast enhancement. Anatomically this mass was located at the abductor hallucis muscle (AH), representing a prominence or hypertrophy of the abductor hallucis muscle (Fig A). The diagnosis was made of a hypertrofic abductor hallucis muscle with narrowing the space for the medial plantar branches of the tibial nerve (circle) at the crossover between the flexor hallucis longus and flexor digitorum longus tendons (arrow), the quadratus plantae muscle (QP) and flexor digitorum brevis muscle (FDB) (Fig B). Example of a normal fibromuscular tunnel (Fig. C). Our patient was treated conservatively first and referred to a foot surgeon

Dutch cooperation programmes to strengthen post-secondary education and training in Africa (1996-2013)

The Dutch government has been supporting higher education in developing countries through cooperation between Dutch higher education and training institutes and partner organizations in the developing countries since the late 1960s.Various programmes have been implemented but the aim in all of them has been to build and strengthen the education and training capacity of organizations/institutes.The map depicts Dutch cooperation programmes to strenghten post-secondary education and training in Africa (1996-2013).ASC – Publicaties niet-programma gebonde

An Isoform of the Eukaryotic Translation Elongation Factor 1A (eEF1a) Acts as a Pro-Viral Factor Required for Tomato Spotted Wilt Virus Disease in <i>Nicotiana benthamiana</i>

The tripartite genome of the negative-stranded RNA virus Tomato spotted wilt orthotospovirus (TSWV) is assembled, together with two viral proteins, the nucleocapsid protein and the RNA-dependent RNA polymerase, into infectious ribonucleoprotein complexes (RNPs). These two viral proteins are, together, essential for viral replication and transcription, yet our knowledge on the host factors supporting these two processes remains limited. To fill this knowledge gap, the protein composition of viral RNPs collected from TSWV-infected Nicotiana benthamiana plants, and of those collected from a reconstituted TSWV replicon system in the yeast Saccharomyces cerevisiae, was analysed. RNPs obtained from infected plant material were enriched for plant proteins implicated in (i) sugar and phosphate transport and (ii) responses to cellular stress. In contrast, the yeast-derived viral RNPs primarily contained proteins implicated in RNA processing and ribosome biogenesis. The latter suggests that, in yeast, the translational machinery is recruited to these viral RNPs. To examine whether one of these cellular proteins is important for a TSWV infection, the corresponding N. benthamiana genes were targeted for virus-induced gene silencing, and these plants were subsequently challenged with TSWV. This approach revealed four host factors that are important for systemic spread of TSWV and disease symptom development

Toward Detecting Polycyclic Aromatic Hydrocarbons on Planetary Objects with ORIGIN

Polycyclic aromatic hydrocarbons (PAHs) are found on various planetary surfaces in the solar system. They are proposed to play a role in the emergence of life, as molecules that are important for biological processes could be derived from them. In this work, four PAHs (pyrene, perylene, anthracene, and coronene) were measured using the ORganics Information Gathering INstrument system (ORIGIN), a lightweight laser desorption ionization-mass spectrometer designed for space exploration missions. In this contribution, we demonstrate the current measurement capabilities of ORIGIN in detecting PAHs at different concentrations and applied laser pulse energies. Furthermore, we show that chemical processing of the PAHs during measurement is limited and that the parent mass can be detected in the majority of cases. The instrument achieves a 3σ detection limit in the order of femtomol mm−2 for all four PAHs, with the possibility of further increasing this sensitivity. This work illustrates the potential of ORIGIN as an instrument for the detection of molecules important for the emergence or presence of life, especially when viewed in combination with previous results by the instrument, such as the identification of amino acids. ORIGIN could be used on a lander or rover platform for future in situ missions to targets in the solar system, such as the icy moons of Jupiter or Saturn

Functional genomics of corrinoid starvation in the organohalide-respiring bacterium Dehalobacter restrictus strain PER-K23

De novo corrinoid biosynthesis represents one of the most complicated metabolic pathways in nature. Organohalide-respiring bacteria (OHRB) have developed different strategies to deal with their need of corrinoid, as it is an essential cofactor of reductive dehalogenases, the key enzymes in OHR metabolism. In contrast to Dehalococcoides mccartyi, the genome of Dehalobacter restrictus strain PER-K23 contains a complete set of corrinoid biosynthetic genes, of which cbiH appears to be truncated and therefore non-functional, possibly explaining the corrinoid auxotrophy of this obligate OHRB. Comparative genomics within Dehalobacter spp. revealed that one (operon-2) of the five distinct corrinoid biosynthesis associated operons present in the genome of D. restrictus appeared to be present only in that particular strain, which encodes multiple members of corrinoid transporters and salvaging enzymes. Operon-2 was highly up-regulated upon corrinoid starvation both at the transcriptional (346-fold) and proteomic level (46-fold on average), in line with the presence of an upstream cobalamin riboswitch. Together, these data highlight the importance of this operon in corrinoid homeostasis in D. restrictus and the augmented salvaging strategy this bacterium adopted to cope with the need for this essential cofacto

Correlation Network Analysis for Amino Acid Identification in Soil Samples With the ORIGIN Space-Prototype Instrument

The detection of biomolecules on Solar System bodies can help us to understand how life emerged on Earth and how life may be distributed in our Solar System. However, the detection of chemical signatures of life on planets or their moons is challenging. A variety of parameters must be considered, such as a suited landing site location, geological and environmental processes favourable to life, life detection strategies, and the application of appropriate and sensitive instrumentation. In this contribution, recent results obtained using our novel laser desorption mass spectrometer ORganics INformation Gathering Instrument (ORIGIN), an instrument designed for in situ space exploration, are presented. We focus in this paper on the detection and identification of amino acid extracts from a natural permafrost sample, as well as in an analogue mixture of soils and amino acids. The resulting dataset was analysed using a correlation network analysis method. Based on mass spectrometric correlation, amino acid signatures were separated from soil signatures, identifying chemically different molecular components in complex samples. The presented analysis method represents an alternative to the typically applied spectra-by-spectra analysis for the evaluation of mass spectrometric data and, therefore, is of high interest for future application in space exploration missions

Prototype laser desorption/ionization mass spectrometer for in situ biosignature detection on ocean worlds

Instrumentatio