Investigation of Islands of Pathogenicity by Bioinformatics Tools

Pathogenicity islands (PAIs) are relatively large DNA segments inserted into the bacterial genome that attribute a variety of virulence characteristics to the microorganisms that possess them.They have deviations in cytosine and guanine (C+G) content different from the rest of the genome located in specific parts.In the study we analyze the genes present in the PAIs of the complete genomes of Brucell abortus by bioinformatics tools.The samples were obtained through the public database National Center for Biotechnology Information (NCBI), where twenty-three complete genomes of B. abortus were collected.After data collection, the phylogenetic tree was created by the MEGAX program, using the Maximum Parsimony method with 1000 bootstrap replicates, from the rRNA16s gene, and the multiple alignment was performed by the BioEdit program, through the ClustalW program.As an external group, the genome used from the Escherichia coli str.K-12 substr.MG1655 strain.The identification of PAIs was performed by the program Gipsy, where two strains were used, one pathogenic to Brucella abortus CIIMS-NV-4, and non-pathogenic Escherichia coli str.K-12 substr.MG1655.In the obtained analyses, four (4) possible genomic islands are found to have a high possible number of pathogenicity islands, with a total of nine (9).The lowest C+G change was 7% while the highest was 23% for PAIs.Thus, the presence of genes encoding proteins linked to virulence factors indicates that these islands are pathogenic.