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TOMÁS , Juan M.

Last name: TOMÁS

First name: Juan M.

September 28, 2017 (v1)

Publication

Metadata-only

In vivo selection of porin-deficient mutants of Klebsiella pneumoniae with increased resistance to cefoxitin and expanded-spectrum cephalosporins

Martínez Martínez, Luis Hernández Allés, Santiago Albertí, Sebastián

Four Klebsiella pneumoniae isolates (LB1, LB2, LB3, and LB4) with increased antimicrobial resistance were obtained from the same patient. The four isolates were indistinguishable in biotype, plasmid content, lipopolysaccharide, and DNA analysis by pulse-field gel electrophoresis. Isolate LB1 made TEM-1 and SHV-1 β-lactamases. Isolates LB2, LB3,...

Uploaded on: March 27, 2023
September 28, 2017 (v1)

Publication

Metadata-only

Development of resistance during antimicrobial therapy caused by insertion sequence interruption of porin genes

Hernández Allés, Santiago Benedí, Vicente J. Martínez Martínez, Luis

We have demonstrated by using an in vitro approach that interruption of the OmpK36 porin gene by insertion sequences (ISs) is a common type of mutation that causes loss of porin expression and increased resistance to cefoxitin in Klebsiella pneumoniae. This mechanism also operates in vivo: of 13 porin-deficient cefoxitin-resistant clinical...

Uploaded on: March 27, 2023