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Due to the emergence of microorganisms resistant to antibiotics and the failure of antibiotic therapies, there is an urgent need to search for new therapeutic options, as well as new molecules with antimicrobial potential. The objective of the present study was to evaluate the in vitro antibacterial activity of Apis mellifera venom collected in the beekeeping areas of the city of Lambayeque in northern Peru against Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus. Bee venom extraction was performed by electrical impulses and separated using the Amicon ultra centrifugal filter. Subsequently, the fractions were quantified by spectrometric 280 nm and evaluated under denaturant conditions in SDS-PAGE. The fractions were pitted against Escherichia coli ATCC 25922, Staphylococcus aureus ATCC 29213, and Pseudomonas aeruginosa ATCC 27853. A purified fraction (PF) of the venom of A. mellifera and three low molecular weight bands of 7 KDa, 6 KDa, and 5 KDa were identified that showed activity against E. coli with a MIC of 6.88 µg/mL, while for P. aeruginosa and S. aureus, it did not present a MIC. No hemolytic activity at a concentration lower than 15.6 µg/mL and no antioxidant activity. The venom of A. mellifera contains a potential presence of peptides and a predilection of antibacterial activity against E. coli.
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Mygalin is a synthetic analog of polyamine spermidine isolated from spider hemocytes. Polyamines show potential therapeutic activity against a wide range of human diseases such as cancer and microbial infections. In this work, we analyzed the antibacterial and antitumoral activities of Mygalin silver nanoparticles synthesized by the photoreduction method. The formation and distribution of MygAgNPs were confirmed by UV-visible spectroscopy, zeta potential, and transmission electron microscopy. The obtained nanoparticles were mostly spherical with a particle size distribution in the range of ~ 10–60 nm. We have demonstrated that MygAgNPs increased the effectiveness of the native Mygalin by approximately 6400-fold. Cytotoxicity tests were performed, and it was possible to reach a concentration that was not toxic to healthy cells (NHI-3T3) and at the same time toxic to the tumor cell line (MCF-7). The obtained results suggest that this system shows potential enhanced antibacterial activity against Escherichia coli, DH5a and anticancer activity against MCF-7 cell line
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Secreted autotransporter toxin (Sat) is a 107-kDa serine protease autotransporter of Enterobacteriaceae (SPATE) presenting cytotoxic activity in renal and bladder cells. Further studies have detected the Sat-encoding gene (sat) in enteroaggregative Escherichia coli (EAEC) and in E. coli strains isolated from neonatal septicemia and meningitis. Here, we investigated the role of Sat as a cytotoxin of EAEC. Sat was purified from a strain of E. coli harboring sat (DEC/Sat+, O126:H2) and used to raise antibodies in rabbit. The presence of Sat was detected by ELISA in the supernatant of 93.7% of EAEC strains harboring sat and in none lacking the gene. The effect of Sat during infection was investigated in polarized Caco-2 cells infected with Sat-producing EAEC (CV323/77,O125ab:H21). This strain induced intense cell detachment, which was inhibited by PMSF or Sat antiserum. Also, sat transcription and Sat production were detected during infection. Here we demonstrate that Sat is internalized in polarized cells leading to F-actin disruption which preceded cell detachment. A comparative study of the toxin action in cell lines corresponding to the infection sites in which bacteria carrying the sat gene have been isolated was performed. Cells originating from the gastrointestinal tract (Caco-2), urinary (LLC-PK1) and endothelium (HUVEC) were incubated with purified Sat. The time required for observation of cell damage differed according to the cell line. HUVEC cells were more sensitive to Sat than cells derived from urinary and intestinal tracts. The intense activity of Sat on the endothelial cells suggests that Sat could also be a virulence factor for the bacteria in the bloodstream. In addition, this is the first work demonstrating that Sat induces cytotoxic effect during EAEC infection in vitro. The cell damage observed during infection indicates that Sat may be another toxin with cytotoxic role in the EAEC pathogenesis.
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OBJECTIVE: . To characterize the nucleoprotein (N) and establish the origin of the rabies virus in dogs coming from Arequipa. MATERIALS AND METHODS.: Thirty samples of nervous tissue from the departments of Arequipa and Puno were analyzed. Total RNA was extracted from the samples and cDNA was synthesized to amplify the nucleoprotein gene, sequence it, and perform bioinformatics analysis. RESULTS: . A defined group was formed with respect to the external group (European bat lyssavirus). This group was classified into two subgroups, one constituted by samples coming from Puno and Arequipa (subgroup A), and another one by samples from Puno (subgroup B), exhibiting a nucleotide identity of 99.9% in subgroup A. This group was classified in two subgroups, one constituted by samples coming from Puno and Arequipa (subgroup A), and another one by samples from Puno (subgroup B), observing a nucleotide identity of 99.9% in subgroup A. CONCLUSIONS.: The groupings of viral sequences show that the cases of canine rabies reported in Arequipa are the result of the expansion of canine rabies from the endemic region of Puno.
OBJETIVOS.: Caracterizar la nucleoproteína (N) y establecer el origen del virus de la rabia en canes procedentes de Arequipa. MATERIALES Y MÉTODOS.: Se analizaron 30 muestras de tejido nervioso procedentes de los departamentos de Arequipa y Puno. Se extrajo el ARN total de las muestras y se sintetizó ADNc para amplificar el gen de la nucleoproteína, secuenciarlo y realizar el análisis bioinformático. RESULTADOS.: Se obtuvo la formación de un grupo definido con respecto al grupo externo (European bat lyssavirus). Este grupo fue clasificado en dos subgrupos, uno constituido por muestras procedentes de Puno y Arequipa (subgrupo A), y otro por muestras de Puno (subgrupo B), observándose una identidad nucleotídica de 99,9% en el subgrupo A. CONCLUSIONES.: Los agrupamientos de las secuencias virales muestran que los casos de rabia canina notificados en Arequipa son el resultado de la expansión de rabia canina procedente de la región endémica de Puno.
Asunto(s)
Nucleoproteínas/genética , Virus de la Rabia/genética , Proteínas Virales/genética , Animales , Perros , PerúRESUMEN
RESUMEN Objetivos. Caracterizar la nucleoproteína (N) y establecer el origen del virus de la rabia en canes procedentes de Arequipa. Materiales y métodos. Se analizaron 30 muestras de tejido nervioso procedentes de los departamentos de Arequipa y Puno. Se extrajo el ARN total de las muestras y se sintetizó ADNc para amplificar el gen de la nucleoproteína, secuenciarlo y realizar el análisis bioinformático. Resultados. Se obtuvo la formación de un grupo definido con respecto al grupo externo (European bat lyssavirus). Este grupo fue clasificado en dos subgrupos, uno constituido por muestras procedentes de Puno y Arequipa (subgrupo A), y otro por muestras de Puno (subgrupo B), observándose una identidad nucleotídica de 99,9% en el subgrupo A. Conclusiones. Los agrupamientos de las secuencias virales muestran que los casos de rabia canina notificados en Arequipa son el resultado de la expansión de rabia canina procedente de la región endémica de Puno.
ABSTRACT Objective . To characterize the nucleoprotein (N) and establish the origin of the rabies virus in dogs coming from Arequipa. Materials and Methods. Thirty samples of nervous tissue from the departments of Arequipa and Puno were analyzed. Total RNA was extracted from the samples and cDNA was synthesized to amplify the nucleoprotein gene, sequence it, and perform bioinformatics analysis. Results . A defined group was formed with respect to the external group (European bat lyssavirus). This group was classified into two subgroups, one constituted by samples coming from Puno and Arequipa (subgroup A), and another one by samples from Puno (subgroup B), exhibiting a nucleotide identity of 99.9% in subgroup A. This group was classified in two subgroups, one constituted by samples coming from Puno and Arequipa (subgroup A), and another one by samples from Puno (subgroup B), observing a nucleotide identity of 99.9% in subgroup A. Conclusions. The groupings of viral sequences show that the cases of canine rabies reported in Arequipa are the result of the expansion of canine rabies from the endemic region of Puno.
Asunto(s)
Animales , Perros , Virus de la Rabia/genética , Proteínas Virales/genética , Nucleoproteínas/genética , PerúRESUMEN
Antibiotic resistance is at dangerous levels and increasing worldwide. The search for new antimicrobial drugs to counteract this problem is a priority for health institutions and organizations, both globally and in individual countries. Sarconesiopsis magellanica blowfly larval excretions and secretions (ES) are an important source for isolating antimicrobial peptides (AMPs). This study aims to identify and characterize a new S. magellanica AMP. RP-HPLC was used to fractionate ES, using C18 columns, and their antimicrobial activity was evaluated. The peptide sequence of the fraction collected at 43.7 min was determined by mass spectrometry (MS). Fluorescence and electronic microscopy were used to evaluate the mechanism of action. Toxicity was tested on HeLa cells and human erythrocytes; physicochemical properties were evaluated. The molecule in the ES was characterized as sarconesin II and it showed activity against Gram-negative (Escherichia coli MG1655, Pseudomonas aeruginosa ATCC 27853, P. aeruginosa PA14) and Gram-positive (Staphylococcus aureus ATCC 29213, Micrococcus luteus A270) bacteria. The lowest minimum inhibitory concentration obtained was 1.9 µM for M. luteus A270; the AMP had no toxicity in any cells tested here and its action in bacterial membrane and DNA was confirmed. Sarconesin II was documented as a conserved domain of the ATP synthase protein belonging to the Fli-1 superfamily. The data reported here indicated that peptides could be alternative therapeutic candidates for use in infections against Gram-negative and Gram-positive bacteria and eventually as a new resource of compounds for combating multidrug-resistant bacteria.
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Objective. To characterize the nucleoprotein (N) and establish the origin of the rabies virus in dogs coming from Arequipa. Materials and Methods. Thirty samples of nervous tissue from the departments of Arequipa and Puno were analyzed. Total RNA was extracted from the samples and cDNA was synthesized to amplify the nucleoprotein gene, sequence it, and perform bioinformatics analysis. Results. A defined group was formed with respect to the external group (European bat lyssavirus). This group was classified into two subgroups, one constituted by samples coming from Puno and Arequipa (subgroup A), and another one by samples from Puno (subgroup B), exhibiting a nucleotide identity of 99.9% in subgroup A. This group was classified in two subgroups, one constituted by samples coming from Puno and Arequipa (subgroup A), and another one by samples from Puno (subgroup B), observing a nucleotide identity of 99.9% in subgroup A. Conclusions. The groupings of viral sequences show that the cases of canine rabies reported in Arequipa are the result of the expansion of canine rabies from the endemic region of Puno.
