Structural elucidation of the O-antigenic polysaccharides from Escherichia coli O21 and the enteroaggregative Escherichia coli strain 105.

The structure of the O-antigen polysaccharide of the lipopolysaccharide from an enteroaggregative Escherichia coli (strain 105) has been elucidated, using primarily one-dimensional and two-dimensional NMR experiments. The sequence of residues was deduced with heteronuclear multiple-bond correlation and NOESY experiments. The structure of the repeating unit of the polysaccharide from the enteroaggregative E. coli is as follows:[sequence: see text] The structure of the O-antigen from enteroaggregative E. coli strain 105 was shown to be identical with that of E. coli O21 by sugar and methylation analyses as well as by 1H-NMR and 13C-NMR spectroscopy.     

Autonomic neuropathy in Fabry disease: a prospective study using the Autonomic Symptom Profile and cardiovascular autonomic function tests

Background  

Fabry patients have symptoms and signs compatible with autonomic dysfunction. These symptoms and signs are considered to be due to impairment of the peripheral nervous system, but findings indicative of autonomic neuropathy in other diseases, such as orthostatic intolerance and male sexual dysfunction, are infrequently reported in Fabry disease. The aim of our study was to investigate autonomic symptoms and cardiovascular autonomic function in a large cohort of male and female Fabry patients.     

Genome sequence and characterization of the bcs clusters for the production of nanocellulose from the low pH resistant strain Komagataeibacter medellinensis ID13488

Komagataeibacter medellinensis ID13488 (formerly Gluconacetobacter medellinensis ID13488) is able to produce crystalline bacterial cellulose (BC) under high acidic growth conditions. These abilities make this strain desirable for industrial BC production from acidic residues (e.g. wastes generated from cider production). To explore the molecular bases of the BC biosynthesis in this bacterium, the genome has been sequenced revealing a sequence of 3.4 Mb containing three putative plasmids of 38.1 kb (pKM01), 4.3 kb (pKM02) and 3.3 Kb (pKM03). Genome comparison analyses of K. medellinensis ID13488 with other cellulose-producing related strains resulted in the identification of the bcs genes involved in the cellulose biosynthesis. Genes arrangement and composition of four bcs clusters (bcs1, bcs2, bcs3 and bcs4) was studied by RT-PCR, and their organization in four operons transcribed as four independent polycistronic mRNAs was determined. qRT-PCR experiments demonstrated that mostly bcs1 and bcs4 are expressed under BC production conditions, suggesting that these operons direct the synthesis of BC. Genomic differences with the close related strain K. medellinensis NBRC 3288 unable to produce BC were also described and discussed.     

The gut of Guatemalan passalid beetles: a habitat colonized by cellobiose- and xylose-fermenting yeasts

The gut of insects is a productive environment for discovering undescribed species of yeasts, and the gut of wood-feeding insects of several families is especially rich in yeasts that carry out the fermentation of cellobiose and xylose. Passalid beetles (Passalidae, Coleoptera) live in dead wood that they ingest as their primary food source. We report the isolation, molecular identification and physiological characterization of 771 yeast cultures isolated from the gut of 16 species of passalids collected in nine localities in Guatemala. Ascomycete yeasts were present in the gut of every passalid studied, and the xylose-fermenting (X-F) yeasts Scheffersomyces shehatae and Scheffersomyces stipitis were the most abundant taxa isolated. The gut of the beetles also contained undescribed cellobiose-fermenting and X-F species in the Lodderomyces, Scheffersomyces and Spathaspora, and undescribed species in Sugiyamaella clades as well as rare yeast species in the Phaffomyces and Spencermartinsiella clades. Basidiomycete yeasts in the genera Cryptococcus and Trichosporon were also common. The yeast species richness was influenced by the host species and the substrate, and gut-inhabiting yeasts have the ability to survive the differing physiological conditions of several gut compartments.