TY - JOUR
T1 - Genomic and molecular characterization of clinical isolates of Enterobacteriaceae harboring mcr-1 in Colombia, 2002 to 2016
AU - Saavedra, Sandra Yamile
AU - Diaz, Lorena
AU - Wiesner, Magdalena
AU - Correa, Adriana
AU - Alejandra Arévalo, Stefany
AU - Reyes, Jinnethe
AU - Hidalgo, Andrea Melissa
AU - De La Cadena, Elsa
AU - Perenguez, Marcela
AU - Montaño, Lucy Angeline
AU - Ardila, Javier
AU - Ríos, Rafael
AU - Ovalle, María Victoria
AU - Díaz, Paula
AU - Porras, Paola
AU - Villegas, Maria V.
AU - Arias, Cesar A.
AU - Beltrán, Mauricio
AU - Duarte, Carolina
N1 - Funding Information:
We acknowledge all public health laboratories from the Red Nacional de Laborato-rios (RNL) and the Colombian Nosocomial Resistance Study Group (Vigilancia CIDEIM) for providing the 5,887 isolates obtained under the previously mentioned surveillance programs. We are grateful to CORPOGEN for providing E. coli J53 Azr for conjugation experiments. We thank the Molecular Genetics and Antimicrobial Resistance Unit, International Center for Microbial Genomics, Universidad El Bosque, for financial support for whole-genome sequencing and analysis of data. We are indebted to Elizabeth Castañeda for support in the development of the study and for thorough manuscript revision. Cesar A. Arias is supported by grant K24 AI114818 from the National Institutes of Health (NIAID).
Publisher Copyright:
© 2017 American Society for Microbiology. All Rights Reserved.
PY - 2017/12
Y1 - 2017/12
N2 - Polymyxins are last-resort antimicrobial agents used to treat infections caused by carbapenem-resistant Enterobacteriaceae. Due to the worldwide dissemination of polymyxin resistance in animal and human isolates, we aimed to characterize polymyxin resistance associated with the presence of mcr-1 in Enterobacteriaceae and nonfermenter Gram-negative bacilli, using isolates collected retrospectively in Colombia from 2002 to 2016. A total of 5,887 Gram-negative clinical isolates were studied, and 513 were found to be resistant to the polymyxins. Susceptibility to colistin was confirmed by broth microdilution for all mcr-1-positive isolates, and these were further subjected to whole-genome sequencing (WGS). The localization of mcr-1 was confirmed by S1 pulsed-field gel electrophoresis (S1-PFGE) and CeuI-PFGE hybridization. Transferability was evaluated by mating assays. A total of 12 colistin-resistant isolates recovered after 2013 harbored mcr-1, including 8 Escherichia coli, 3 Salmonella enterica serovar Typhimurium, and 1 Klebsiella pneumoniae isolate. E. coli isolates were unrelated by PFGE and belonged to 7 different sequence types (STs) and phylogroups. S. Typhimurium and K. pneumoniae isolates belonged to ST34 and ST307, respectively. The mcr-1 gene was plasmid borne in all isolates but two E. coli isolates which harbored it on the chromosome. Conjugation of mcr-1 was successful in 8 of 10 isolates (8.2 105 to 2.07 101 cell per recipient). Plasmid sequences showed that the mcr-1 plasmids belonged to four different Inc groups (a new IncP-1 variant and the IncFII, IncHI1, and IncH families). Our results indicate that mcr-1 is circulating in clinical isolates of colistin-resistant Enterobacteriaceae in Colombia and is mainly harbored in transferable plasmids.
AB - Polymyxins are last-resort antimicrobial agents used to treat infections caused by carbapenem-resistant Enterobacteriaceae. Due to the worldwide dissemination of polymyxin resistance in animal and human isolates, we aimed to characterize polymyxin resistance associated with the presence of mcr-1 in Enterobacteriaceae and nonfermenter Gram-negative bacilli, using isolates collected retrospectively in Colombia from 2002 to 2016. A total of 5,887 Gram-negative clinical isolates were studied, and 513 were found to be resistant to the polymyxins. Susceptibility to colistin was confirmed by broth microdilution for all mcr-1-positive isolates, and these were further subjected to whole-genome sequencing (WGS). The localization of mcr-1 was confirmed by S1 pulsed-field gel electrophoresis (S1-PFGE) and CeuI-PFGE hybridization. Transferability was evaluated by mating assays. A total of 12 colistin-resistant isolates recovered after 2013 harbored mcr-1, including 8 Escherichia coli, 3 Salmonella enterica serovar Typhimurium, and 1 Klebsiella pneumoniae isolate. E. coli isolates were unrelated by PFGE and belonged to 7 different sequence types (STs) and phylogroups. S. Typhimurium and K. pneumoniae isolates belonged to ST34 and ST307, respectively. The mcr-1 gene was plasmid borne in all isolates but two E. coli isolates which harbored it on the chromosome. Conjugation of mcr-1 was successful in 8 of 10 isolates (8.2 105 to 2.07 101 cell per recipient). Plasmid sequences showed that the mcr-1 plasmids belonged to four different Inc groups (a new IncP-1 variant and the IncFII, IncHI1, and IncH families). Our results indicate that mcr-1 is circulating in clinical isolates of colistin-resistant Enterobacteriaceae in Colombia and is mainly harbored in transferable plasmids.
KW - Colombia
KW - Enterobacteriaceae
KW - Genomic
KW - mcr-1
UR - http://www.scopus.com/inward/record.url?scp=85034961923&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85034961923&partnerID=8YFLogxK
U2 - 10.1128/AAC.00841-17
DO - 10.1128/AAC.00841-17
M3 - Article
C2 - 28893788
AN - SCOPUS:85034961923
VL - 61
JO - Antimicrobial Agents and Chemotherapy
JF - Antimicrobial Agents and Chemotherapy
SN - 0066-4804
IS - 12
M1 - e00841
ER -