| Autor: |
Sisti S; Laboratory of Microbiology and Virology, Vita-Salute San Raffaele University, Milan, Italy, Diotti RA; Laboratory of Microbiology and Virology, Vita-Salute San Raffaele University, Milan, Italy, Caputo V; Laboratory of Microbiology and Virology, Vita-Salute San Raffaele University, Milan, Italy, Libera M; Laboratory of Microbiology and Virology, Vita-Salute San Raffaele University, Milan, Italy, Ferrarese R; Laboratory of Microbiology and Virology, Vita-Salute San Raffaele University, Milan, Italy, Carletti S; Laboratory of Microbiology and Virology, IRCCS San Raffaele Scientific Institute, Milan, Italy, Rizzi P; Laboratory of Microbiology and Virology, Vita-Salute San Raffaele University, Milan, Italy, Cirillo DM; Emerging Bacterial Pathogens Unit, San Raffaele Scientific Institute, Milan, Italy, Lorenzin G; Emerging Bacterial Pathogens Unit, San Raffaele Scientific Institute, Milan, Italy, Clementi M; Laboratory of Microbiology and Virology, Vita-Salute San Raffaele University, Milan, Italy; Laboratory of Microbiology and Virology, IRCCS San Raffaele Scientific Institute, Milan, Italy, Mancini N; Laboratory of Microbiology and Virology, Vita-Salute San Raffaele University, Milan, Italy; Laboratory of Microbiology and Virology, IRCCS San Raffaele Scientific Institute, Milan, Italy, Clementi N; Laboratory of Microbiology and Virology, Vita-Salute San Raffaele University, Milan, Italy; Laboratory of Microbiology and Virology, IRCCS San Raffaele Scientific Institute, Milan, Italy |
| Abstrakt: |
The spread of multidrug-resistant (MDR) K. pneumoniae carbapenemase-producing bacteria (KPC) is one of the most serious threats to global public health. Due to the limited antibiotic options, colis- tin often represents a therapeutic choice. In this study, we performed Whole-Genome Sequencing (WGS) by Illumina and Nanopore platforms on four colistin-resistant K. pneumoniae isolates (CoRKp) to explore the resistance profile and the mutations involved in colistin resistance. Mapping reads with reference sequence of the most com- mon genes involved in colistin resistance did not show the presence of mobile colistin resistance (mcr) genes in all CoRKp. Complete or partial deletions of mgrB gene were observed in three out of four CoRKp, while in one CoRKp the mutation V24G on phoQ was identified. Complementation assay with proper wild type genes restored colistin susceptibility, validating the role of the amino acid substitution V24G and, as already described in the literature, confirming the key role of mgrB alterations in colistin resistance. In conclusion, this study allowed the identification of the novel mutation on phoQ gene involved in colistin resistance phenotype. |
