Genomic insights into members of the candidate phylum Hyd24-12 common in mesophilic anaerobic digesters

Members of the candidate phylum Hyd24-12 are globally distributed, but no genomic information or knowledge about their morphology, physiology or ecology is available. In this study, members of the Hyd24-12 lineage were shown to be present and abundant in full-scale mesophilic anaerobic digesters at Danish wastewater treatment facilities. In some samples, a member of the Hyd24-12 lineage was one of the most abundant genus-level bacterial taxa, accounting for up to 8% of the bacterial biomass. Three closely related and near-complete genomes were retrieved using metagenome sequencing of full-scale anaerobic digesters. Genome annotation and metabolic reconstruction showed that they are Gram-negative bacteria likely involved in acidogenesis, producing acetate and hydrogen from fermentation of sugars, and may play a role in the cycling of sulphur in the digesters. Fluorescence in situ hybridization revealed single rod-shaped cells dispersed within the flocs. The genomic information forms a foundation for a more detailed understanding of their role in anaerobic digestion and provides the first insight into a hitherto undescribed branch in the tree of life

How sulphate-reducing microorganisms cope with stress: lessons from systems biology

Sulphate-reducing microorganisms (SRMs) are a phylogenetically diverse group of anaerobes encompassing distinct physiologies with a broad ecological distribution. As SRMs have important roles in the biogeochemical cycling of carbon, nitrogen, sulphur and various metals, an understanding of how these organisms respond to environmental stresses is of fundamental and practical importance. In this Review, we highlight recent applications of systems biology tools in studying the stress responses of SRMs, particularly Desulfovibrio spp., at the cell, population, community and ecosystem levels. The syntrophic lifestyle of SRMs is also discussed, with a focus on system-level analyses of adaptive mechanisms. Such information is important for understanding the microbiology of the global sulphur cycle and for developing biotechnological applications of SRMs for environmental remediation, energy production, biocorrosion control, wastewater treatment and mineral recovery

Notes for genera: basal clades of Fungi (including Aphelidiomycota, Basidiobolomycota, Blastocladiomycota, Calcarisporiellomycota, Caulochytriomycota, Chytridiomycota, Entomophthoromycota, Glomeromycota, Kickxellomycota, Monoblepharomycota, Mortierellomycota, Mucoromycota, Neocallimastigomycota, Olpidiomycota, Rozellomycota and Zoopagomycota)

Compared to the higher fungi (Dikarya), taxonomic and evolutionary studies on the basal clades of fungi are fewer in number. Thus, the generic boundaries and higher ranks in the basal clades of fungi are poorly known. Recent DNA based taxonomic studies have provided reliable and accurate information. It is therefore necessary to compile all available information since basal clades genera lack updated checklists or outlines. Recently, Tedersoo et al. (MycoKeys 13:1--20, 2016) accepted Aphelidiomycota and Rozellomycota in Fungal clade. Thus, we regard both these phyla as members in Kingdom Fungi. We accept 16 phyla in basal clades viz. Aphelidiomycota, Basidiobolomycota, Blastocladiomycota, Calcarisporiellomycota, Caulochytriomycota, Chytridiomycota, Entomophthoromycota, Glomeromycota, Kickxellomycota, Monoblepharomycota, Mortierellomycota, Mucoromycota, Neocallimastigomycota, Olpidiomycota, Rozellomycota and Zoopagomycota. Thus, 611 genera in 153 families, 43 orders and 18 classes are provided with details of classification, synonyms, life modes, distribution, recent literature and genomic data. Moreover, Catenariaceae Couch is proposed to be conserved, Cladochytriales Mozl.-Standr. is emended and the family Nephridiophagaceae is introduced

Spatially resolved profiling of colorectal cancer lipid biochemistry via DESI imaging mass spectrometry to reveal morphology-dependent alterations in fatty acid metabolism

Background: Lipid metabolic alterations are recognised as potential oncogenic triggers that promote malignant transformation. Here we performed spatially-resolved profiling of lipid signatures in colorectal cancer (CRC) tissue and matched healthy mucosa using desorption electrospray ionisation imaging mass spectrometry (DESI-MSI). The objectives of this study were to comprehensively define the CRC ‘lipidome’ and to assess lipid signatures in discrete histological regions-of-interest, specifically morphologically bland peri-tumoural epithelium (PT-e) and tumour stroma (T-s). Methods: Fresh frozen tissue sections from 42 patients with confirmed CRC were subjected to negative-ion mode DESI-MSI analysis. Mass spectra in the 200-1000 m/zrange were collated from CRC epithelium (CRC-e), PT-e, T-s and healthy tumour-remote epithelium (TR-e). Spectral signatures were subjected to multivariate analysis using a recursive maximum margin criterion (RMMC) algorithm operating in MATLAB. Results: Increased levels of long/very-long chain fatty acids (LCFA/VLCFA) were seen in CRC-e compared with TR-e(AUC = 0.99). Correspondingly, increased expression of lipogenic and elongase enzymes was found on IHC. Transmission electron microscopy was performed to evaluate peroxisomal distribution and morphology in CRC-e, as these organelles metabolise LCFA/VLCFA through β-oxidation, to negligibly low levels, in healthy cells. No discernible difference in peroxisomal distribution, abundance or structure was found between CRC-e and TR-e. PT-e demonstrated a lipid expression pattern almost identical to that of CRC-e, and markedly different from TR-e (AUC = 0.89). Conclusions: A shift towards increased LCFA/VLCFA production may be an important metabolic trait in CRC facilitated through upregulation of de novo lipogenesis and fatty acid elongation and concurrent impairment of peroxisomal β-oxidation. This phenotype was also observed in morphologically bland PT-e, suggesting that enhanced de novo LCFA/VLCFA biosynthesis and impaired peroxisomal function may represent important steps in peri-tumoural field cancerisation