Location, synthesis and function of glycolipids and polyglycerolphosphate lipoteichoic acid in Gram-positive bacteria of the phylum Firmicutes.

Published versio

Recombinant Porphyromonas gingivalis FimA preproprotein expressed in Escherichia coli is lipidated and the mature or processed recombinant FimA protein forms a short filament in vitro.

The gram-negative anaerobic bacterium Porphyromonas gingivalis is an etiologically important pathogen for chronic periodontal diseases in adults. Our previous study suggested that the major structural components of both Fim and Mfa fimbriae in this organism are secreted through their lipidated precursors. In this study, we constructed Escherichia coli strains expressing various fimA genes with or without the 5\u27-terminal DNA region encoding the signal peptide, and we determined whether lipidation of recombinant FimA proteins occurred in E. coli. Lipidation occurred for a recombinant protein from the fimA gene with the 5\u27-terminal DNA region encoding the signal peptide but not for a recombinant protein from the fimA gene without the signal-peptide-encoding region, as revealed by [3H]palmitic acid labeling experiments. A TLR2-dependent signaling response was induced by the recombinant protein from the fimA gene with the signal-peptide-encoding region but not by a recombinant protein from the fimA gene with the signal-peptide-encoding region that had a base substitution causing an amino acid substitution (C19A). Electron microscopic analysis revealed that recombinant FimA (A-47 - W-383) protein was autopolymerized to form filamentous structures of about 80 nm in length in vitro. The results suggest that FimA protein, a major subunit of Fim fimbriae, is transported to the outer membrane by the lipoprotein sorting system, and a mature or processed FimA protein on the outer membrane is autopolymerized to form Fim fimbriae.This is a revised document of the article published in Canadian Journal of Microbiology, 56(11), pp.959-967; 2010. The contents of modification is published in Canadian Journal of Microbiology, 57(1), pp.68; 2011. It is available at http://dx.doi.org/10.1139/W10-114

DC Breakdown Voltage of Carbon Dioxide Medium under Needle to Plane Electrode

This paper reports the experimental results on thecorona onset voltage and breakdown voltage by positiveand negative dc discharges in carbon dioxide mediumwithin the pressure range of 0.1 to 15MPa under theneedle to plane electrode. From the experimental resultsof dc discharge, negative corona discharges are observedmore clearly in liquid and supercritical phase than in gasphase of carbon dioxide. However, in our experimentalcondition, positive corona discharge was not found for dcdischarges. The breakdown mechanism in liquid can beclassified into two categories on account of the bubbletriggeredformation

Comparative analysis of traditional and modern production small architectural forms by the example of Suzdal

The article examines the characteristics of production and the role of small architectural forms in the design of the urban environment. It revealed the use of traditional, national typicalRussian architectural elements in the arrangement of modern cities, and explore the use of new technologies in the manufacture of small architectural forms. On the basis of the investigated material conclusions about current views on landscape and architectural design and their relationship with the culture of Russia, its traditions