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Bulla, A. C. S.

Publications and source records attributed to Bulla, A. C. S..

2 recordsLinked to original sources

Functional annotation hypothetical proteins: a world to be explored in drug development in Trypanosomatids

Hypothetical proteins can provide an alternative pathway for finding potential targets in the development of new drugs due to the fact that many Neglected tropical diseases are caused by Trypanosomatids (Chagas Disease, Leishmaniasis, and Human African Trypanosomiasis). In this work, we focus on applying functional prediction methods based on both sequence and structure to analyze the hypothetical proteins of the pathogenic agents that cause these diseases: T. cruzi (Tcr), T. brucei brucei (Tbr), T. brucei gambiense (Tbg), L. infantum (Lif), L. donovani (Ldo), and L. braziliensis (Lbz). By consulting databases and servers, we have predicted functional domains for twenty-six proteins in Tcr, thirteen in Tbr, fifteen in Tbg, ten in Lif, and one in both Ldo and Lbz. With the goal of developing multi-target therapies, we grouped the domains according to how they are shared among the organisms and investigated those that are shared among more species. By examining the existing literature using specific search strategies, we described what has already been reported for these domains and also analyzed protein structures and sequences, describing mutations among the species and potential drug sites. The published works have unveiled that some of these domains are non-essential for trypanosomatids, like the TRX domain, while others demand further investigation due to a lack of information about metabolic processes (UFC1, Ufm1, ACBP, AAA 18, and Fe-S). Although, we have identified three noteworthy domains that hold promise as targets: TPR, which plays a crucial role in the ciliogenesis process; Nuc deoxyrib tr, essential in purine recycling and recovery mechanisms; and MIX, important for protein targeting and the assembly of complexes such as COX. These three domains are promising targets for drug development due to their conservation, their potential to affect multiple species and their exclusivity.

bioinformatics↗

The Escherichia coli TolC efflux pump protein is immunogenic and elicits protective antibodies

Antimicrobial resistance is an increasing worldwide public health burden that threatens to make the existent antimicrobials obsolete. Among the mechanisms of antimicrobial resistance is the overexpression of efflux pumps, such as the AcrA-AcrB-TolC which extrude diverse compounds, reducing the intracellular concentration of antimicrobials. TolC is the outer membrane protein of this pump and has recently gained attention as a therapeutic target. However, little is known about the immune response generated against the TolC protein. Here we evaluated the cellular and humoral immune response against the TolC from Escherichia coli. An in silico epitope prediction of the E. coli TolC showed several residues could bind to human antibodies, and we showed that human plasma presented anti-TolC IgG and IgA antibodies. Gram-negative infected patients presented a slight increase in anti-TolC IgM amounts, compared to controls. Recombinant E. coli TolC protein stimulated macrophages in vitro to produce nitric oxide, as well as IL-6 and TNF-, assessed by Griess assay and ELISA, respectively. Immunization of mice with TolC intraperitoneally and an in vitro re-stimulation of lymph node cells led to increased percentage of T cell proliferation and IFN{gamma} production, evaluated by flow cytometry and ELISA, respectively. We observed that TolC mouse immunization stimulated anti-TolC IgM and IgG production, with a higher level of IgG1 and IgG2, amongst the IgG subclasses. Finally, TolC IgG from mouse immune serum could bind to live E. coli, increase bacterial uptake by macrophages in vitro. TolC immunized mice had a survival rate increased in 60% post infection with E. coli. Our results showed that TolC is immunogenic, activating macrophages, T and B cells, leading to the production of protective antibodies against E. coli.

immunology↗