Premium
Outer Membrane Vesicles from Clinical Strains of Escherichia coli Can Cause Megalocytosis and DNA Damage in HeLa Cells
Author(s) -
MoralesLozada Yermary,
GómezMoreno Ramón,
BaergaOrtiz Abel
Publication year - 2017
Publication title -
the faseb journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.709
H-Index - 277
eISSN - 1530-6860
pISSN - 0892-6638
DOI - 10.1096/fasebj.31.1_supplement.lb55
Subject(s) - bacterial outer membrane , periplasmic space , biology , escherichia coli , bacteria , virulence , mutant , microbiology and biotechnology , hela , secretion , dna damage , dna , vesicle , enterobacteriaceae , gene , cell , biochemistry , membrane , genetics
Outer membrane vesicles (OMV) are proteoliposomes secreted by almost all gram‐negative bacteria with several functions like the transportation of bacterial virulence and survival factors. OMV provide an insoluble secretion pathway for gram‐negative bacteria and are responsible for the release of outer membrane and periplasm content out of the cell. It has been shown that certain OMV promote aberrant growth in mammalian cells upon contact. The pks island gene cluster, a virulence factor in some strains of extraintestinal E. coli , encodes enzymes purported to make a genotoxic compound that we hypothesize is transported towards cells by OMV. The main objective of this investigation is to compare the biological activity of OMV isolated from E. coli strains harboring and lacking the pks island genes. As a preliminary result, we observe megalocytosis, a hallmark of genotoxic activity, on HeLa cells treated with OMV isolated from E. coli IHE3034 ( pks+ ) in comparison with cells exposed to OMV isolated from IHE3034 (Δ clbP ), which lacks the pks island . Surprisingly, immunoblotting analysis targeting the phosphorylation of the histone H 2 AX shows greater DNA damage in cells treated with the IHE3034 wildtype strain, but also, DNA damage was observed in IHE3034 (Δ clbP ) mutant strain. Overall, these results show that OMV treated cells exhibit morphological abnormalities similar to those observed in cells exposed to pks positive bacterial cells, thus demonstrating a link between the genotoxic activity of the pks island and the production of OMV by the bacteria. Support or Funding Information RISE Program Grant #R25GM061151‐15