Microbial communities of the house fly Musca domestica vary with geographical location and habitat.

House flies (Musca domestica) are widespread, synanthropic filth flies commonly found on decaying matter, garbage, and feces as well as human food. They have been shown to vector microbes, including clinically relevant pathogens. Previous studies have demonstrated that house flies carry a complex and variable prokaryotic microbiota, but the main drivers underlying this variability and the influence of habitat on the microbiota remain understudied. Moreover, the differences between the external and internal microbiota and the eukaryotic components have not been examined. To obtain a comprehensive view of the fly microbiota and its environmental drivers, we sampled over 400 flies from two geographically distinct countries (Belgium and Rwanda) and three different environments-farms, homes, and hospitals. Both the internal as well as external microbiota of the house flies were studied, using amplicon sequencing targeting both bacteria and fungi. Results show that the house fly's internal bacterial community is very diverse yet relatively consistent across geographic location and habitat, dominated by genera Staphylococcus and Weissella. The external bacterial community, however, varies with geographic location and habitat. The fly fungal microbiota carries a distinct signature correlating with the country of sampling, with order Capnodiales and genus Wallemia dominating Belgian flies and genus Cladosporium dominating Rwandan fly samples. Together, our results reveal an intricate country-specific pattern for fungal communities, a relatively stable internal bacterial microbiota and a variable external bacterial microbiota that depends on geographical location and habitat. These findings suggest that vectoring of a wide spectrum of environmental microbes occurs principally through the external fly body surface, while the internal microbiome is likely more limited by fly physiology.

Apibacter muscae sp. nov., a novel bacterial species isolated from house flies.

We describe the isolation and characterization of three bacterial isolates from the common house fly, Musca domestica, caught in Londerzeel, Belgium and Huye District, Rwanda. Although isolated from distinct geographical locations, the strains show >99 % identical 16S rRNA gene sequences and are <95 % identical to type strains of Apibacter species. Whole-genome sequences were obtained for all three strains. The genomes are 2.4-2.5 Mb with a G+C content of ~30.3 mol%. Bacteriological and biochemical analysis of the strains demonstrate distinctly different characteristics compared to known Apibacter species. Particularly, the three strains investigated in this study can be distinguished from the known Apibacter species (Apibacter mensalisand Apibacter adventoris) through urease and ß-glucosidase activities. Whole-cell fatty acid methyl ester analysis shows that the fatty acid composition of the novel strains is also unique. On the basis of phylogenetic, genotypic and phenotypic data, we propose to classify these isolates as representatives of a novel species of the genus Apibacter, Apibacter muscae sp. nov., in reference to its prevalence in house flies, with strain G8T (=LMG 30898T=DSM 107922T) as the type strain.

Physiology, ecology and industrial applications of aroma formation in yeast.

Yeast cells are often employed in industrial fermentation processes for their ability to efficiently convert relatively high concentrations of sugars into ethanol and carbon dioxide. Additionally, fermenting yeast cells produce a wide range of other compounds, including various higher alcohols, carbonyl compounds, phenolic compounds, fatty acid derivatives and sulfur compounds. Interestingly, many of these secondary metabolites are volatile and have pungent aromas that are often vital for product quality. In this review, we summarize the different biochemical pathways underlying aroma production in yeast as well as the relevance of these compounds for industrial applications and the factors that influence their production during fermentation. Additionally, we discuss the different physiological and ecological roles of aroma-active metabolites, including recent findings that point at their role as signaling molecules and attractants for insect vectors.

Indole-like Trk receptor antagonists.

The virtual screening for new scaffolds for TrkA receptor antagonists resulted in potential low molecular weight drug candidates for the treatment of neuropathic pain and cancer. In particular, the compound (Z)-3-((5-methoxy-1H-indol-3-yl)methylene)-2-oxindole and its derivatives were assessed for their inhibitory activity against Trk receptors. The IC50 values were computationally predicted in combination of molecular and fragment-based QSAR. Thereafter, based on the structure-activity relationships (SAR), a series of new compounds were designed and synthesized. Among the final selection of 13 compounds, (Z)-3-((5-methoxy-1-methyl-1H-indol-3-yl)methylene)-N-methyl-2-oxindole-5-sulfonamide showed the best TrkA inhibitory activity using both biochemical and cellular assays and (Z)-3-((5-methoxy-1-methyl-1H-indol-3-yl)methylene)-2-oxindole-5-sulfonamide was the most potent inhibitor of TrkB and TrkC.

Novel transcripts reveal a complex structure of the human TRKA gene and imply the presence of multiple protein isoforms.

BACKGROUND: Tropomyosin-related kinase A (TRKA) is a nerve growth factor (NGF) receptor that belongs to the tyrosine kinase receptor family. It is critical for the correct development of many types of neurons including pain-mediating sensory neurons and also controls proliferation, differentiation and survival of many neuronal and non-neuronal cells. TRKA (also known as NTRK1) gene is a target of alternative splicing which can result in several different protein isoforms. Presently, three human isoforms (TRKAI, TRKAII and TRKAIII) and two rat isoforms (TRKA L0 and TRKA L1) have been described. RESULTS: We show here that human TRKA gene is overlapped by two genes and spans 67 kb--almost three times the size that has been previously described. Numerous transcription initiation sites from eight different 5' exons and a sophisticated splicing pattern among exons encoding the extracellular part of TRKA receptor indicate that there might be a large variety of alternative protein isoforms. TrkA genes in rat and mouse appear to be considerably shorter, are not overlapped by other genes and display more straightforward splicing patterns. We describe the expression profile of alternatively spliced TRKA transcripts in different tissues of human, rat and mouse, as well as analyze putative endogenous TRKA protein isoforms in human SH-SY5Y and rat PC12 cells. We also characterize a selection of novel putative protein isoforms by portraying their phosphorylation, glycosylation and intracellular localization patterns. Our findings show that an isoform comprising mainly of TRKA kinase domain is capable of entering the nucleus. CONCLUSIONS: Results obtained in this study refer to the existence of a multitude of TRKA mRNA and protein isoforms, with some putative proteins possessing very distinct properties.