RESUMO
A multi-resistant strain of Vibrio parahaemolyticus was isolated from a tropical estuary in Rio de Janeiro, Brazil. Genome sequencing was conducted to establish the molecular basis of antibiotic resistance in this organism. The genetic content of this strain revealed it to be a non-virulent lineage that nevertheless possesses several antibiotic resistance determinants.
Assuntos
Antibacterianos/farmacologia , Resistência Microbiana a Medicamentos/genética , Vibrio parahaemolyticus/efeitos dos fármacos , Vibrio parahaemolyticus/genética , Microbiologia da Água , Genômica , Testes de Sensibilidade Microbiana , Vibrio parahaemolyticus/isolamento & purificaçãoRESUMO
A multi-resistant strain of Vibrio parahaemolyticus was isolated from a tropical estuary in Rio de Janeiro, Brazil. Genome sequencing was conducted to establish the molecular basis of antibiotic resistance in this organism. The genetic content of this strain revealed it to be a non-virulent lineage that nevertheless possesses several antibiotic resistance determinants.
Assuntos
Vibrio parahaemolyticus/efeitos dos fármacos , Vibrio parahaemolyticus/genética , Microbiologia da Água , Resistência Microbiana a Medicamentos/genética , Antibacterianos/farmacologia , Vibrio parahaemolyticus/isolamento & purificação , Testes de Sensibilidade Microbiana , GenômicaRESUMO
Advances brought about by omics-based approaches have revolutionized our understanding of the diversity and ecological processes involving marine archaea, bacteria, and their viruses. This broad review discusses recent examples of how genomics, metagenomics, and ecogenomics have been applied to reveal the ecology of these biological entities. Three major topics are covered in this revision: (i) the novel roles of microorganisms in ecosystem processes; (ii) virus-host associations; and (iii) ecological associations of microeukaryotes and other microbes. We also briefly comment on the discovery of novel taxa from marine ecosystems; development of a robust taxonomic framework for prokaryotes; breakthroughs on the diversity and ecology of cyanobacteria; and advances on ecological modelling. We conclude by discussing limitations of the field and suggesting directions for future research.
Assuntos
Ecologia , Metagenômica , Água do Mar/microbiologia , Água do Mar/virologia , Archaea/genética , Archaea/fisiologia , Bactérias/genética , Fenômenos Fisiológicos Bacterianos/genética , Biodiversidade , Evolução Biológica , Classificação , Cianobactérias/fisiologia , Ecossistema , Genômica , Interações entre Hospedeiro e Microrganismos/fisiologia , Biologia Marinha , Fenômenos Fisiológicos Virais/genética , Vírus/genéticaRESUMO
The red seaweeds belonging to the genus Laurencia are well known as halogenated secondary metabolites producers, mainly terpenoids and acetogennins. Several of these chemicals exhibit important ecological roles and biotechnological applications. However, knowledge regarding the genes involved in the biosynthesis of these compounds is still very limited. We detected 20 different genes involved in the biosynthesis of terpenoid precursors, and 21 different genes coding for terpene synthases that are responsible for the chemical modifications of the terpenoid precursors, resulting in a high diversity of carbon chemical skeletons. In addition, we demonstrate through molecular and cytochemical approaches the occurrence of the mevalonate pathway involved in the biosynthesis of terpenes in L. dendroidea. This is the first report on terpene synthase genes in seaweeds, enabling further studies on possible heterologous biosynthesis of terpenes from L. dendroidea exhibiting ecological or biotechnological interest.
Assuntos
Laurencia/química , Terpenos/química , Alquil e Aril Transferases/genética , Alquil e Aril Transferases/metabolismo , Vias Biossintéticas , Configuração de Carboidratos , DNA Complementar/biossíntese , DNA Complementar/genética , Laurencia/enzimologia , Laurencia/genética , Ácido Mevalônico/metabolismo , Modelos Moleculares , Terpenos/metabolismo , Transcriptoma/genéticaRESUMO
We report the genome sequence of Vibrio cholerae strain IEC224, which fails to ferment sucrose. It was isolated from a cholera outbreak in the Amazon. The defective sucrose phenotype was determined to be due to a frameshift mutation, and a molecular marker of the Latin American main epidemic lineage was identified.
Assuntos
Cólera/microbiologia , Epidemias , Genoma Bacteriano , Sacarose/metabolismo , Vibrio cholerae/classificação , Vibrio cholerae/genética , Brasil/epidemiologia , Cólera/epidemiologia , Humanos , Dados de Sequência Molecular , Vibrio cholerae/metabolismoRESUMO
An online scheme to assign Stenotrophomonas isolates to genomic groups was developed using the multilocus sequence analysis (MLSA), which is based on the DNA sequencing of selected fragments of the housekeeping genes ATP synthase alpha subunit (atpA), the recombination repair protein (recA), the RNA polymerase alpha subunit (rpoA) and the excision repair beta subunit (uvrB). This MLSA-based scheme was validated using eight of the 10 Stenotrophomonas species that have been previously described. The environmental and nosocomial Stenotrophomonas strains were characterised using MLSA, 16S rRNA sequencing and DNA-DNA hybridisation (DDH) analyses. Strains of the same species were found to have greater than 95% concatenated sequence similarity and specific strains formed cohesive readily recognisable phylogenetic groups. Therefore, MLSA appeared to be an effective alternative methodology to amplified fragment length polymorphism fingerprint and DDH techniques. Strains of Stenotrophomonas can be readily assigned through the open database resource that was developed in the current study (www.steno.lncc.br/).
Assuntos
DNA Bacteriano/genética , Tipagem de Sequências Multilocus/métodos , RNA Ribossômico 16S/genética , Stenotrophomonas/genética , Técnicas de Tipagem Bacteriana , RNA Polimerases Dirigidas por DNA/genética , Humanos , FilogeniaRESUMO
An online scheme to assign Stenotrophomonas isolates to genomic groups was developed using the multilocus sequence analysis (MLSA), which is based on the DNA sequencing of selected fragments of the housekeeping genes ATP synthase alpha subunit (atpA), the recombination repair protein (recA), the RNA polymerase alpha subunit (rpoA) and the excision repair beta subunit (uvrB). This MLSA-based scheme was validated using eight of the 10 Stenotrophomonas species that have been previously described. The environmental and nosocomial Stenotrophomonas strains were characterised using MLSA, 16S rRNA sequencing and DNA-DNA hybridisation (DDH) analyses. Strains of the same species were found to have greater than 95 percent concatenated sequence similarity and specific strains formed cohesive readily recognisable phylogenetic groups. Therefore, MLSA appeared to be an effective alternative methodology to amplified fragment length polymorphism fingerprint and DDH techniques. Strains of Stenotrophomonas can be readily assigned through the open database resource that was developed in the current study (www.steno.lncc.br/).
