Comparative genetic characterization of Enteroaggregative Escherichia coli strains recovered from clinical and non-clinical settings.

The origin of pathogenic Enteroaggregative Escherichia coli (EAEC), a major causative agent of childhood diarrhea worldwide, remains ill-defined. The objective of this study was to determine the relative prevalence of EAEC in clinical and non-clinical sources and compare their genetic characteristics in order to identify strains that rarely and commonly cause human diarrhea. The virulence gene astA was commonly detectable in both clinical and non-clinical EAEC, while clinical isolates, but not the non-clinical strains, were consistently found to harbor other virulence factors such as aap (32%), aatA (18%) and aggR (11%).

Emergence of KPC-2-producing Pseudomonas aeruginosa sequence type 463 isolates in Hangzhou, China.

Thirty-nine Klebsiella pneumoniae carbapenemase (KPC)-producing Pseudomonas aeruginosa isolates, all exhibiting high-level resistance to carbapenems and other β-lactam antibiotics, were isolated in Hangzhou, China. Molecular epidemiology analysis indicated the presence of two dominant clones, namely, clones A and B, both of which belong to sequence type 463 (ST463). A genetic environment analysis demonstrated that both clones harbor an ISKpn8 transposase, bla(KPC-2), and an ISKpn6-like transposase.

Substitutions of Ser83Leu in GyrA and Ser80Leu in ParC Associated with Quinolone Resistance in Acinetobacter pittii.

To investigate the prevalence and the mechanism of quinolone-resistant Acinetobacter pittii, 634 Acinetobacter calcoaceticus-Acinetobacter baumannii complex isolates were collected throughout Zhejiang Province. Identification of isolates was conducted by matrix-assisted laser desorption ionization/time of flight mass spectrometry (MALDI-TOF MS), blaOXA-51-like gene, and partial RNA polymerase β-subunit (rpoB) amplification. Twenty-seven isolates of A.