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The in situ occurrence and localization of 3-hydroxy oxylipins (fatty acids) in selected members of the Lipomycetaceae were mapped with immunofluorescence microscopy. As was found previously in Dipodascopsis uninucleata, fluorescence was associated with the meiospores of all the strains tested. These results further highlight this yeast family as a rich source of 3-hydroxy oxylipins, which have potent biological activity in mammalian cells and are hence of biological interest. In addition, immunogold labelling of Dipodascopsis uninucleata revealed lipid globules with a high affinity for the antibody specific to 3-hydroxy fatty acids. These lipids were produced during the generative stage. These observations may aid in the further optimization and extraction of these novel compounds. [ABSTRACT FROM AUTHOR]

Abstract Background In Gram-negative bacteria, the outer membrane is composed of an asymmetric lipid bilayer of phopspholipids and lipopolysaccharides, and the transmembrane proteins that reside in this membrane are almost exclusively β-barrel proteins. These proteins are inserted into the membrane by a highly conserved and essential machinery, the BAM complex. It recognizes its substrates, unfolded outer membrane proteins (OMPs), through a C-terminal motif that has been speculated to be species-specific, based on theoretical and experimental results from only two species, Escherichia coli and Neisseria meningitidis, where it was shown on the basis of individual sequences and motifs that OMPs from the one cannot easily be over expressed in the other, unless the C-terminal motif was adapted. In order to determine whether this species specificity is a general phenomenon, we undertook a large-scale bioinformatics study on all predicted OMPs from 437 fully sequenced proteobacterial strains. Results We were able to verify the incompatibility reported between Escherichia coli and Neisseria meningitidis, using clustering techniques based on the pairwise Hellinger distance between sequence spaces for the C-terminal motifs of individual organisms. We noticed that the amino acid position reported to be responsible for this incompatibility between Escherichia coli and Neisseria meningitidis does not play a major role for determining species specificity of OMP recognition by the BAM complex. Instead, we found that the signal is more diffuse, and that for most organism pairs, the difference between the signals is hard to detect. Notable exceptions are the Neisseriales, and Helicobacter spp. For both of these organism groups, we describe the specific sequence requirements that are at the basis of the observed difference. Conclusions Based on the finding that the differences between the recognition motifs of almost all organisms are small, we assume that heterologous overexpression of almost all OMPs should be feasible in E. coli and other Gram-negative bacterial model organisms. This is relevant especially for biotechnology applications, where recombinant OMPs are used e.g. for the development of vaccines. For the species in which the motif is significantly different, we identify the residues mainly responsible for this difference that can now be changed in heterologous expression experiments to yield functional proteins.

Abstract: A 36 channel reactor system combining high-throughput experimentation (HTE) with operando UV/vis diffuse reflectance (UV/vis-DR) spectroscopy is introduced and applied for the oxidative dehydrogenation of propane (ODP) to propene at 500°C over polycrystalline V2O3, VO2, and V2O5. This set-up enabled to monitor reaction-induced reduction of V2O5 to V2O3, and VO2 during the ODP reaction. The operando UV/vis-DR spectroscopic analysis along the catalyst bed demonstrated that the vanadium oxidation state at the reactor inlet is higher than at the reactor outlet. This is due to the depletion of oxygen and the enrichment of propene down stream along the catalyst bed. [Copyright &y& Elsevier]

Moritella viscosa is a Gram-negative psychrophilic bacterium that causes winter ulcer disease in farmed fish. The aim of the study was to describe an outer membrane protein of roughly 20 kDa in pathogenic M. viscosa and to compare the coincident protein of strains isolated from different fish species and geographical locations. The protein was isolated from a pathogenic strain of M. viscosa. An oligopeptide sequence obtained with MS/MS analysis showed homology to Escherichia coli OmpA and Neisseria surface protein A. The protein was named Moritella viscosa outer membrane protein 1 (MvOmp1), and sequence analysis confirmed that it is an integral membrane protein consisting of eight antiparallel β-strands, three short periplasmic turns and four long hydrophilic extracellular loops. The encoding gene, mvomp1, was fully sequenced in nine strains representing different serotypes and phenotypes. The results revealed some differences in the extracellular loops between strains. The mvomp1 gene was cloned and expressed in E. coli, and the recombinant product was recognized by anti- M. viscosa polyclonal antisera. The results indicate that MvOmp1 is a major protective antigen of M. viscosa. The results open up possibilities for use of the protein as a part of a subunit vaccine in the future. [ABSTRACT FROM AUTHOR]