purification-refolding-to-amyloid-fibrils-his-6-tagged-recombinant

Purification and Refolding to Amyloid Fibrils of (His)<sub>6</sub>-tagged Recombinant Shadoo Protein Expressed as Inclusion Bodies in<em> E. coli</em>

The Escherichia coli expression system is a powerful tool for the production of recombinant eukaryotic proteins. We use it to produce Shadoo, a protein ...

INRA

A quantitative PCR (qPCR) assay using SYBR Green I was developed based on the published sequence of the gtxA gene from Gallibacterium anatis. This method produced reliable specificity, sensitivity, and repeatability. The detection rate of Gallibacterium in 181 clinical samples was 36.5% (66/181) by qPCR, which was superior to the detection rate of Gallibacterium-specific PCR (0/181) and an isolation and identification assay (18.2% or 33/181). No association was found between the prevalence of Gallibacterium and the age of the chickens. Gallibacterium infection was detected in one 4-day-old chicken, showing that infection can occur much earlier than the previously stated fourth week of life. Tissue sample analysis showed that Gallibacterium is mainly located in the trachea and ovaries, based on results from three groups of chicken with different health statuses. Furthermore, a titer analysis suggested that Gallibacterium loads in different organs may correlate with different clinical manifestations of disease. Thus, the qPCR assay developed in the present study is useful for identification and quantitative analysis of gtxA-containing Gallibacterium in various tissue samples from birds and for the assessment of the pathogenic mechanisms of Gallibacterium.

Development and preliminary application of a quantitative PCR assay for detecting gtxA-containing Gallibacterium species in chickens.

Lipid membrane can enhance prion protein (PrP) pathological fibrillogenesis. A neuronal paralog of PrP, named Shadoo (Sho), is localized to similar membrane environment as PrP and can also convert to amyloid-like fibrilles. To gain insight into the role of Sho in prion diseases, we studied Sho interactions with cellular membrane models. Sho was found to bind anionic lipid vesicles. Spectroscopic and microscopic data showed that membrane-associated Sho slowly converted into amyloid fibers. Furthermore, binding of Sho to anionic liposomes has a disruptive effect on the integrity of the lipid bilayer leading to the formation of supramolecular lipid-protein complexes. In consequence, the role of Sho in prion diseases might depend on the oligomerization state of Sho but also the nature of these lipoprotein assembles.

Article	Year
Development and preliminary application of a quantitative PCR assay for detecting gtxA-containing Gallibacterium species in chickens. Avian diseases\| PubMed ID: 22856188	2012
Shadoo binds lipid membranes and undergoes aggregation and fibrillization. Biochemical and biophysical research communications\| PubMed ID: 23911790	2013

Qiaojing Li

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