Experimental Infection and Detection of Necrotizing Hepatopancreatitis Bacterium in the American Lobster Homarus americanus

Necrotizing hepatopancreatitis bacterium (NHPB) is an obligated intracellular bacteria causing severe hepatopancreatic damages and mass mortalities in penaeid shrimp. The worldwide distribution of penaeid shrimp as alien species threatens the life cycle of other crustacean species. The aim of the experiment was to evaluate the possibility of experimentally infecting the American lobster (Homarus americanus) with NHPB extracted from shrimp hepatopancreas. Homogenates from infected shrimp were fed by force to lobsters. Other group of lobsters was fed with homogenates of NHPB-free hepatopancreas. After the 15th day from initial inoculation, the presence of NHPB was detected by polymerase chain reaction in feces and hepatopancreas from lobsters inoculated with infected homogenates. Necrotized spots were observed in the surface of lobster hepatopancreas. In contrast, lobsters fed on NHPB-free homogenates resulted negative for NHPB. Evidence suggests the plasticity of NHPB which can infect crustacean from different species and inhabiting diverse latitudes. Considering the results, the American lobster could be a good candidate to maintain available NHPB in vivo

Antiproliferative activity of protein extracts from the black clam (Chione fluctifraga) on human cervical and breast cancer cell lines

The wide diversity of the marine environment has been an important resource for the discovery of new bioactive agents from marine organisms. The aim of this study was to obtain protein extracts from the clam Chione fluctifraga and determine its antiproliferative activity against cervical and breast cancer cells. The extracts were obtained by ammonium sulfate fractionation, gel filtration and ion exchange chromatography. Antiproliferative activity was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5- diphenyltetrazolium bromide assay (MTT). The results showed that 3F3 had antiproliferative effect against HeLa and MDA-MB-231 cell lines with IC50 values of 138.035 and 157.19 μg/ml, respectively, and 2F2 showed IC50 values of 67.46 μg/ml on HeLa cells. These results suggest that protein extracts from C. fluctifraga might be potential anticancer agents.Key words: Protein extracts, clam, antiproliferative activity, breast cancer, cervical cancer

Purificacion y caracterizacion parcial de la profenoloxidasa de hemocitos de camarón café (Penaues californiensis)

Impreso y PD

Análisis bioinformático del sistema flagelar de la alphaproteobacteria tipo rickettsia Candidatus Hepatobacter penaei

The presence of flagellar systems is common in several free-living bacteria; however, these have been considered absent in bacteria belonging to the Rickettsiales order. Candidatus Hepatobacter penaei is a marine Rickettsial bacterium described as a motile microorganism propelled by a flagellar system that facilitates infection. This bacterium represents a major risk of infection in shrimp farms. Therefore, the objective of this study was to determine the presence of genes encoding the flagellar system proteins of the bacterium Candidatus Hepatobacter penaei. The genomic sequence of the GenBank database with accession number NZ_JQAJ00000000.1, was analyzed. After genes were identified, amino acid sequences were deduced. The amino acid sequences of the flagellar system were identified by BLASTP through multiple alignment of conserved domains. Subsequently, a modeling process of FlhA protein was performed and compared with the protein reported for Oceanibaculum indicum considering the formation of α-helixes and β-sheets. Results showed the presence of some amino acid sequences of the genes related to bacterial flagellar system as MotA FliG, FliN, FliL FlhA, FlhB, FliQ FliR and FliF. Finally, these results suggest that Candidatus Hepatobacter penaei is a rickettsial bacterium having a flagellar system, which possibly confers motility and take part in the infection process in hosts such as marine crustaceans.La presencia de sistemas flagelares es común en muchas bacterias de vida libre, sin embargo, estos han sido considerados ausentes en bacterias del orden Rickettsiales. Candidatus Hepatobacter penaei es una bacteria Rickettsial de origen marino descrita como un microorganismo con motilidad, propulsada por un sistema flagelar, el cual también facilita la infección. Siendo esta bacteria uno de los principales riesgos de infección en granjas camaronícolas. El objetivo de este trabajo fue determinar la presencia de genes que codifiquen proteínas del sistema flagelar de la bacteria Candidatus Hepatobacter penaei. Para el análisis se utilizó la secuencia genómica la base de datos del GenBank con número de acceso NZ_JQAJ00000000.1, una vez detectados los genes, se dedujeron las secuencias de aminoácidos. Las secuencias de aminoácidos del sistema flagelar se identificaron mediante BlastP, por medio de un alineamiento múltiple de dominios conservados. Posteriormente, se realizó un modelado de la proteína FlhA y se comparó con la proteína reportada para Oceanibaculum indicum para la conformación hojas β y α hélices. Los resultados mostraron la presencia de algunas secuencias de aminoácidos relacionadas con los genes del sistema flagelar de la bacteria como MotA, FliG, FliN, FliL FlhA, FlhB, FliQ, FliR y FliF. Finalmente, estos resultados sugieren que Candidatus Hepatobacter penaei es una bacteria tipo Rickettsia que posee un sistema flagelar, el cual posiblemente le confiere motilidad y forma parte del proceso de infección en hospederos como crustáceos marinos

Análisis bioinformático del sistema flagelar de la alphaproteobacteria tipo rickettsia Candidatus Hepatobacter penaei

The presence of flagellar systems is common in several free-living bacteria; however, these have been considered absent in bacteria belonging to the Rickettsiales order. Candidatus Hepatobacter penaei is a marine Rickettsial bacterium described as a motile microorganism propelled by a flagellar system that facilitates infection. This bacterium represents a major risk of infection in shrimp farms. Therefore, the objective of this study was to determine the presence of genes encoding the flagellar system proteins of the bacterium Candidatus Hepatobacter penaei. The genomic sequence of the GenBank database with accession number NZ_JQAJ00000000.1, was analyzed. After genes were identified, amino acid sequences were deduced. The amino acid sequences of the flagellar system were identified by BLASTP through multiple alignment of conserved domains. Subsequently, a modeling process of FlhA protein was performed and compared with the protein reported for Oceanibaculum indicum considering the formation of -helixes and -sheets. Results showed the presence of some amino acid sequences of the genes related to bacterial flagellar system as MotA FliG, FliN, FliL FlhA, FlhB, FliQ FliR and FliF. Finally, these results suggest that Candidatus Hepatobacter penaei is a rickettsial bacterium having a flagellar system, which possibly confers motility and take part in the infection process in hosts such as marine crustaceans.La presencia de sistemas flagelares es común en muchas bacterias de vida libre, sin embargo, estos han sido considerados ausentes en bacterias del orden Rickettsiales. Candidatus Hepatobacter penaei es una bacteria Rickettsial de origen marino descrita como un microorganismo con motilidad, propulsada por un sistema flagelar, el cual también facilita la infección. Siendo esta bacteria uno de los principales riesgos de infección en granjas camaronícolas. El objetivo de este trabajo fue determinar la presencia de genes que codifiquen proteínas del sistema flagelar de la bacteria Candidatus Hepatobacter penaei. Para el análisis se utilizó la secuencia genómica la base de datos del GenBank con número de acceso NZ_JQAJ00000000.1, una vez detectados los genes, se dedujeron las secuencias de aminoácidos. Las secuencias de aminoácidos del sistema flagelar se identificaron mediante BlastP, por medio de un alineamiento múltiple de dominios conservados. Posteriormente, se realizó un modelado de la proteína FlhA y se comparó con la proteína reportada para Oceanibaculum indicum para la conformación hojas y hélices. Los resultados mostraron la presencia de algunas secuencias de aminoácidos relacionadas con los genes del sistema flagelar de la bacteria como MotA, FliG, FliN, FliL FlhA, FlhB, FliQ, FliR y FliF. Finalmente, estos resultados sugieren que Candidatus Hepatobacter penaei es una bacteria tipo Rickettsia que posee un sistema flagelar, el cual posiblemente le confiere motilidad y forma parte del proceso de infección en hospederos como crustáceos marinos