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p27SJ is a novel protein from a callus culture of St. John's wort that modulates transcription of the HIV-1 promoter in several mammalian cells [Darbinian-Sarkissian, N., Darbinyan, A., Otte, J., Radhakrishnan, S., Sawaya, B.E., Arzumanyan, A., Chipitsyna, G., Popov, Y., Rappaport, J., Amini, S., Khalili, K., 2006. p27(SJ), a novel protein from St. John's wort, that suppresses expression of HIV-1 genome. Gene Ther. 13, 288-295]. Here, we armed p27SJ with signals from Ig-kappa light chain that allow its efficient excretion from the cells, and from HIV-1 Tat that facilitates its uptake by other cells for its utilization by a protein transduction method. We demonstrate that treatment of cells containing the HIV-1 LTR with conditioned media from cells expressing the armed p27SJ ((exc)p27SJ(upt)) results in suppression of the viral activation by the C/EBPbeta transcription factor. Once imported into the cells, (exc)p27SJ(upt) impacts the nuclear localization of C/EBPbeta and by retaining the protein in the cytoplasm affects its DNA binding and hence transcriptional activity. The armed p27SJ also inhibits Tat-induced activation of the LTR and decreases the level of viral replication in promonocytic cells including U-937 and T-lymphocytic cells. Our observations introduce a new bi-directional protein transduction system with a broad spectrum of applications for manufacturing therapeutic peptides by a specific group of cells called donor, and delivery to the target cells named recipient. Furthermore, our results support the utility of soluble p27SJ in suppressing transcription and replication of HIV-1 by interfering with the function of cellular proteins such as C/EBPbeta and viral activators including Tat.

Herbal medicine requires searching for new sources with antimicrobial activity. Alkanna sp. (Boraginaceae) is widely used in medicine due to detoxification and antibacterial effects. The aim of this study was to obtain Alkanna orientalis (L.) Boiss. plant callus extracts, to investigate antimicrobial activity of extracts against bacteria and yeast and to reveal responsible mechanisms. Callus tissue cultures have been obtained using different nutrient media. Antimicrobial activity and minimal inhibitory concentrations (MIC) were determined by the methods of extract diffusion in agar and dilution using different test-microorganisms. Quantity and quality of naphthoquinones were determined using spectrophotometric and high performance liquid chromatographic analyses. H ? /K ? exchange by whole cells was assayed using selective electrodes, ATPase activity and SH-groups number of membrane vesicles-by spectrophotometric methods. It was revealed that callus extracts containing naphthoquinones (0.19 ± 0.01 %) possessed bacteriostatic activity against gram-positive bacteria including pathogenic ones (MIC were 125-750 lg/mL -1 ), and bactericidal activity against lactic acid bacteria (Lactobacillus acidophilus, L. rhamnosus) (MIC was 250 lg/mL). MIC against Enterococcus hirae was 250 lg/mL of callus extract or 31.25 lg/ mL of shikonin. It depended on the medium content, cultivation duration and the activity remained for 10-11 years. Moreover, intact root extracts inhibited H ?

Functional foods hold a great promise for future trends in human nutrition. Consumption of milk and milk products has a pronounced probiotic effects together with the expected modification of allergenic properties of milk due to the process of fermentation. The proteolytic system of lactic acid bacteria consists a cell wall bound proteinase and several intracellular peptidases, and can contribute to the liberation of bioactive peptides. Food-derived bioactive peptides are claimed to be health-enhancing components, which can be used for functional food.In this study the attention was focused on homemade milk products from the Balkan region and also from Armenia and Iraq, as a source of newly potential starters for application in the food industry. In this context the aim of this study was to screen the proteolytic activity of newly isolated strains, by determination of the optimal conditions of proteolysis for reducing the milk proteins allergenicity. The proteolytic activity of 50 lactic acid strains was tested against major milk proteins. Some of the studied strains showed relatively high proteolytic activity towards α-casein, α-lactalbumin and β-lactoglobulin reducing their concentration proved by the HPLC analysis and Tricine-PAGE. Hydrolysis of milk protein generated peptides with antimicrobial effect against Esherichia coli, Staphylococcus aureus, Listeria innocua, Enterobacter aerogenes, Enterococcus avium and Salmonela choleraesuis.Consequently to obtain a maximal effect of the product, a combination of strains with different properties could be used as starters in milk industry.