Genetic organization of transposase regions surrounding blaKPC carbapenemase genes on plasmids from Klebsiella strains isolated in a New York City hospital.

Carbapenem-resistant Klebsiella strains carrying Klebsiella pneumoniae carbapenemases (KPC) are endemic to New York City and are spreading across the United States and internationally. Recent studies have indicated that the KPC structural gene is located on a 10-kb plasmid-borne element designated Tn4401. Fourteen Klebsiella pneumoniae strains and one Klebsiella oxytoca strain isolated at a New York City hospital in 2005 carrying either bla(KPC-2) or bla(KPC-3) were examined for isoforms of Tn4401.

A high-throughput HERG potassium channel function assay: an old assay with a new look.

In this paper, we describe an assay using radioactive rubidium (86Rb) efflux to screen functional human ether-a go-go-related gene (HERG) K+ channels in a high-throughput screening (HTS) format. This assay offers an alternative way to examine junctional interactions between chemical compounds and HERG K+ channels. Follow-up experiments and discussions were carried out to address a variety of factors that affect potency evaluation within the Rb efflux assay.