Autor(es):
Castro, Pedro Soares 
; Marques, Diana ; Demyanchuk, Sergey ; Faustino, A. ; Santos, P. M.
Data: 2011
Identificador Persistente: http://hdl.handle.net/1822/16069
Origem: RepositóriUM - Universidade do Minho
Assunto(s): Pseudomonas aeruginosa; Genome; Clinical isolates; Mobilome
Descrição
Recently, we have set a collaboration with Hospital de Braga, located in the North of
Portugal, that handles over 600 P. aeruginosa isolates per year, aiming to rouse a
holistic research approach to provide relevant information and tools to the clinicians to
circumvent the multi-resistance phenomena in P. aeruginosa. Since then, we have set
procedures aiming a systematic phenotypic characterization of the clinical isolates and
developed strategies for the identification of pathogenicity islands and SNPs among the
clinical isolates via comparative genomics. In this context, we have determined the full
genome sequence of two clinical isolates using the high-throughput system Illumina
Genome Analyzer IIx. These two clinical isolates, named 138244 and 152504, are
representatives of allelic sequence types ST175 (widely disseminated and associated
with multidrug-resistance) and ST560 (rare allele), respectively. Importantly, under
standardized experimental procedures, isolate 138244 did not produce pigments and
evidenced an antibiotic pan-resistant phenotype whereas 152504 produced a high
amount of pyocyanin pigment and was susceptible to all antibiotics tested. A
comparative genomic analysis using the genome sequences of both isolates and of all P.
aeruginosa strains deposited in Genbank so far, allowed the identification of the
accessory genome content of both isolates. Apparently, isolate 152504 harbors in its
genome 243 unique genes, often clustered together in the same locus. Based on the
genome annotation information, the pool of unique genes mainly encode several
virulence factors, chemical stress resistance systems as well as 106 hypothetical
proteins, some of which predicted members of the secretome of P. aeruginosa 152504.
The accessory genome of 138244 mainly includes genes associated with mobile
elements (phages, transposases, integrons) and genes encoding for 190 hypothetical
proteins. Currently, research approaches are focused on the functional elucidation of
sets of genes encoding hypothetical proteins of both isolates and in the description and
characterization of their secretomes.
