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Analysis of the proteome of any Bacillus thuringiensis strain should provide important information about mechanisms of infection, interactions with host organisms, and very importantly, about the molecular mechanisms by which the bacterium is able to survive under non-favorable conditions. In order to address these important issues, we analyzed the proteome of the crystal-forming Bacillus thuringiensis strain BGSC-4AW1 (var. andalousiensis ). This proteomic analysis reveals the presence of important proteins for cell survival and cell proliferation associated with the exosporium/coat/crystal complexes. Although, at the present time, we cannot discriminate among the specific sub proteomes associated with these developmental stages, it is clear that this information should be useful for mapping the cellular mechanisms involved in cell survival and adaptation to detrimental environmental conditions. It is also clear that the proteomic analysis offers a wider window into the potential biotechnological applications of Bt .

Background S-nitrosylation of mitochondrial enzymes involved in energy transfer under nitrosative stress may result in ATP deficiency. We investigated whether α-lipoic acid, a powerful antioxidant, could alleviate nitrosative stress by regulating S-nitrosylation, which could result in retaining the mitochondrial enzyme activity. Methods In this study, we have identified the S-nitrosylated forms of subunit 1 of dihydrolipoyllysine succinyltransferase (complex III), and subunit 2 of the α-ketoglutarate dehydrogenase complex by implementing a fluorescence-based differential quantitative proteomics method. Results We found that the activities of these two mitochondrial enzymes were partially but reversibly inhibited by S-nitrosylation in cultured endothelial cells, and that their activities were partially restored by supplementation of α-lipoic acid. We show that protein S-nitrosylation affects the activity of mitochondrial enzymes that are central to energy supply, and that α-lipoic acid protects mitochondrial enzymes by altering S-nitrosylation levels. Conclusions Inhibiting protein S-nitrosylation with α-lipoic acid seems to be a protective mechanism against nitrosative stress. General significance Identification and characterization of these new protein targets should contribute to expanding the therapeutic power of α-lipoic acid and to a better understanding of the underlying antioxidant mechanisms.

Aim: Peripheral blood-derived endothelial cells (pBD-ECs) are an attractive tool for cell therapies and tissue engineering, but have been limited by their low isolation yield. We increase pBD-EC yield via administration of the chemokine receptor type 4 antagonist AMD3100, as well as via a diluted whole blood incubation (DWBI). Materials & Methods: Porcine pBD-ECs were isolated using AMD3100 and DWBI and tested for EC markers, acetylated LDL uptake, growth kinetics, metabolic activity, flow-mediated nitric oxide production and seeded onto titanium tubes implanted into vessels of pigs. Results: DWBI increased the yield of porcine pBD-ECs 6.6-fold, and AMD3100 increased the yield 4.5-fold. AMD3100-mobilized ECs were phenotypically indistinguishable from nonmobilized ECs. In porcine implants, the cells expressed endothelial nitric oxide synthase, reduced thrombin-antithrombin complex systemically and prevented thrombosis. Conclusion: Administration of AMD3100 and the DWBI method both increase pBD-EC yield.