RESUMO
A multilocus sequence analysis (MLSA) was carried out to delineate Aeromonas hydrophila from fish in Uganda. Five housekeeping genes including recA, gyrB, metG, gltA and pps; and the 16S rRNA gene were amplified and sequenced from a total of nine A. hydrophila isolates. The obtained sequences were edited, and consensus sequences generated for each gene locus. The housekeeping gene sequences were concatenated and phylogenetic analysis performed in MEGA version 7.0.2. Pairwise distances ranged from 0.000 to 0.118, highest within the gltA gene locus and lowest within the 16S rRNA gene. The average evolutionary diversity within isolates from the same source ranged between 0.002 and 0.037, and it was 0.033 between the different sources. Similar tree topologies were obtained from the different gene loci with recA, metG and gyrB being more consistent in discriminating isolates according to sources while the 16S rRNA gene had the lowest resolution. The concatenated tree had the highest discriminatory power. This study revealed that A. hydrophila strains infecting fish in Uganda are of diverse genotypes suggesting different sources of infection in a given outbreak. Efforts to minimize spread of the bacteria across sources should be emphasized to control infections of mixed genotypes.
Assuntos
Aeromonas hydrophila/genética , Variação Genética , Genótipo , Infecções por Bactérias Gram-Negativas/veterinária , Tipagem de Sequências Multilocus/métodos , Filogenia , Animais , Técnicas de Tipagem Bacteriana , DNA Bacteriano/genética , DNA Ribossômico/genética , Doenças dos Peixes/epidemiologia , Doenças dos Peixes/microbiologia , Genes Essenciais , Infecções por Bactérias Gram-Negativas/epidemiologia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Uganda/epidemiologiaRESUMO
Background: The antimicrobial resistance catastrophe is a growing global health threat and predicted to be worse in developing countries. Phages for Global Health (PGH) is training scientists in these regions to isolate relevant therapeutic phages for pathogenic bacteria within their locality, and thus contributing to making phage technology universally available. Materials and Methods: During the inaugural PGH workshop in East Africa, samples from Ugandan municipal sewage facilities were collected and two novel Escherichia coli lytic phages were isolated and characterized. Results: The phages, UP19 (capsid diameter â¼100 nm, contractile tail â¼120/20 nm) and UP30 (capsid diameter â¼70 nm, noncontractile tail of â¼170/20 nm), lysed â¼82% and â¼36% of the 11 clinical isolates examined, respectively. The genomes of UP19 (171.402 kb, 282 CDS) and UP30 (49.834 kb, 75 CDS) closely match the genera Dhakavirus and Tunavirus, respectively. Conclusion: The phages isolated have therapeutic potential for further development against E. coli infections.