Virulence determinants in genetically heterogeneous populations of Aeromonads recovered from an urban lagoon.

The diversity and distribution of Aeromonas spp. associated with virulence profiles from the Rodrigo de Freitas Lagoon were investigated using phylogenetic analysis of gyrB/rpoB gene sequences for speciation. The concatenated gyrB/rpoB gene sequences clustered into five species: Aeromonas punctata/caviae (n = 37), A.

Keratinolytic activity of LFB-FIOCRUZ 1266 enhanced by whole-cell mutagenesis.

Discarded feathers represent an important residue from the poultry industry and are a rich source of keratin. LFB-FIOCRUZ 1266, previously isolated from industrial poultry wastes, was used in this work and, through random mutation using ethyl methanesulfonate, ten strains were selected based on the size of their degradation halos. The feather degradation was increased to 115% and all selected mutants showed 1.

Detection of human fecal contamination by nifH gene quantification of marine waters in the coastal beaches of Rio de Janeiro, Brazil.

The identification of fecal pollution in aquatic ecosystems is one of the requirements to assess the possible risks to human health. In this report, physicochemical parameters, Escherichia coli enumeration and Methanobrevibacter smithii nifH gene quantification were conducted at 13 marine waters in the coastal beaches of Rio de Janeiro, Brazil. The pH, turbidity, dissolved oxygen, temperature, and conductivity, carried out by mobile equipment, revealed varied levels due to specific conditions of the beaches.

Fecal pollution source tracking in waters intended for human supply based on archaeal and bacterial genetic markers.

The determination of fecal pollution sources in aquatic ecosystems is essential to estimate associated health risks. In this study, we evaluate eight microbial source tracking (MST) markers including host-specific Bacteroidales and Methanobrevibacter spp. for discrimination between human, bovine, equine, and swine fecal contamination in waters intended for human supply.