Evolution-based protein engineering: functional switching between transthyretins and 5-hydroxyisourate hydrolases.

Transthyretin (TTR) is a vertebrate-exclusive transport protein that plays a key role in binding and distributing thyroid hormones. However, its evolutionary origin lies in the duplication of the gene that encoding the enzyme 5-hydroxyisourate hydrolase (HIUase), which is involved in uric acid metabolism. Unlike TTR, HIUase is ubiquitous in both prokaryotes and eukaryotes, with the exception of hominids.

New Approaches to the Prevention of Visceral Leishmaniasis: A Review of Recent Patents of Potential Candidates for a Chimeric Protein Vaccine.

The development of prophylactic vaccines is important in preventing and controlling diseases such as visceral leishmaniasis (VL), in addition to being an economic measure for public health. Despite the efforts to develop a vaccine against human VL caused by , none is available, and the focus has shifted to developing vaccines against canine visceral leishmaniasis (CVL). Currently, commercially available vaccines are targeted at CVL but are not effective.

Structural and immunological characterization of a new nucleotidyltransferase-like antigen from Paracoccidioides brasiliensis.

Pb27 antigen is an interesting alternative to immunological diagnosis of Paracoccidioidomycosis (PCM) and has demonstrated to be protective in experimental PCM. Its tertiary structure and possible function remained unknown till now. To study Pb27 at the atomic level, the recombinant protein was expressed in Escherichia coli BL21(DE3), purified, and its three-dimensional structure was solved by X-ray crystallography.

A combined approach for enhancing the stability of recombinant cis-dihydrodiol naphthalene dehydrogenase from Pseudomonas putida G7 allowed for the structural and kinetic characterization of the enzyme.

The second enzyme of the naphthalene degradation pathway in Pseudomonas putida G7 is NahB, a dehydrogenase that converts cis-1,2-dihydroxy-1,2-dihydronaphthalene to 1,2-dihydroxynaphthalene. We report the cloning, optimization of expression, purification, kinetic studies and preliminary structural characterization of the recombinant NahB. The nahB gene was cloned into a T7 expression vector and the enzyme was overexpressed in Escherichia coli Rosetta (DE3) as an N-terminal hexa-histidine-tagged protein (6xHis-NahB).

Evaluation of parasitological and immunological parameters of Leishmania chagasi infection in BALB/c mice using different doses and routes of inoculation of parasites.

Experimental vaccines to protect against visceral leishmaniasis (VL) have been developed by using BALB/c mice infected with a large (10⁷ to 10⁸) inoculum of parasites. Remarkably, prior literature has reported that the poor protection observed is mainly due to the high susceptibility of this strain. To determine factors inherent to mice that might abrogate vaccine-induced efficacy, the present research sought to investigate the impact of the administration of different infective inoculums of Leishmania chagasi (syn.

Vaccination with the Leishmania infantum ribosomal proteins induces protection in BALB/c mice against Leishmania chagasi and Leishmania amazonensis challenge.

Leishmania chagasi and Leishmania amazonensis are the etiologic agents of different clinical forms of human leishmaniasis in South America. In an attempt to select candidate antigens for a vaccine protecting against different Leishmania species, the efficacy of vaccination using Leishmania ribosomal proteins and saponin as adjuvant was examined in BALB/c mice against challenge infection with both parasite species. Mice vaccinated with parasite ribosomal proteins purified from Leishmania infantum plus saponin showed a specific production of IFN-γ, IL-12 and GM-CSF after in vitro stimulation with L.

Specific serodiagnosis of canine visceral leishmaniasis using Leishmania species ribosomal protein extracts.

In the present work, we have analyzed the antigenicity of Leishmania species ribosomal proteins (LRPs). To accomplish this, Leishmania infantum ribosomes were biochemically purified from promastigote cytosolic extracts, and their reactivities were analyzed by using the sera from dogs naturally infected with L. infantum.