RESUMO
Escherichia coli ST131 is a clinical challenge due to its multidrug resistant profile and successful global spread. They are often associated with complicated infections, particularly urinary tract infections (UTIs). Bacteriocins play an important role to outcompete other microorganisms present in the human gut. Here, we characterized bacteriocin-encoding plasmids found in ST131 isolates of patients suffering from a UTI using both short- and long-read sequencing. Colicins Ia, Ib and E1, and microcin V, were identified among plasmids that also contained resistance and virulence genes. To investigate if the potential transmission range of the colicin E1 plasmid is influenced by the presence of a resistance gene, we constructed a strain containing a plasmid which had both the colicin E1 and blaCMY-2 genes. No difference in transmission range was found between transformant and wild-type strains. However, a statistically significantly difference was found in adhesion and invasion ability. Bacteriocin-producing isolates from both ST131 and non-ST131 lineages were able to inhibit the growth of other E. coli isolates, including other ST131. In summary, plasmids harboring bacteriocins give additional advantages for highly virulent and resistant ST131 isolates, improving the ability of these isolates to compete with other microbiota for a niche and thereby increasing the risk of infection.
RESUMO
We assessed the IgG levels anti-diphtheria (D-Ab) and T cell counts (CD4+ and CD8+) in HIV-1 infected subjects undergoing or not highly active antiretroviral therapy (HAART). Approximately 70% of all HIV-1 patients were unprotected against diphtheria. There were no differences in D-Ab according to CD4 counts. Untreated patients had higher D-Ab (geometric mean of 0.62 IU/ml) than HAART-patients (geometric mean of 0.39 IU/ml). The data indicated the necessity of keeping all HIV-1 patients up-to-date with their vaccination.