Project description:The Antibiotic Resistant Sepsis Pathogens Framework Initiative aims to develop a framework dataset of 5 sepsis pathogens (Escherichia coli, Klebsiella pneumoniae complex, Staphylococcus aureus, Streptococcus pneumoniae and Streptococcus pyogenes, 5 strains each) using an integrated application of genomic, transcriptomic, metabolomic and proteomic technologies. This submission contains the results from six Klebsiella strains (four Klebsiella variicola: AJ005, AJ292, 03-311-0071, 04153260899A and two Klebsiella pneumoniae: AJ218, KPC2) grown in either RPMI or pooled human sera. Six replicates of each condition were subjected to shotgun proteomics and label-free MS1-based quantitation.
Project description:The emergence of colistin resistance in carbapenem-resistant and extended-spectrum ß-lactamase (ESBL)-producing bacteria is a significant threat to human health, and new treatment strategies are urgently required. Here we investigated the ability of the safe-for-human use ionophore PBT2 to restore antibiotic sensitivity in several polymyxin-resistant, ESBL-producing, carbapenem resistant Gram-negative human pathogens. PBT2 was observed to resensitize Klebsiella pneumoniae, Escherichia coli, Acinetobacter baumannii, and Pseudomonas aeruginosa to last-resort polymyxin class antibiotics, including a ‘next generation’ polymyxin derivative, FADDI-287. To gain additional insight into the potential mechanism of action of PBT2, we analyzed the transcriptome of K. pneumoniae and E. coli in the presence of sub-inhibitory concentrations of PBT2. Treatment with PBT2 was associated with multiple stress responses in both K. pneumoniae and E. coli. Significant changes in the transcription of transition metal ion homeostasis genes were observed in both strains.
Project description:The emergence of polymyxin resistance in carbapenem-resistant and extended-spectrum -lactamase (ESBL)-producing bacteria is a critical threat to human health, and new treatment strategies are urgently required. Here, we investigated the ability of the safe-for-human use ionophore PBT2 to restore antibiotic sensitivity in polymyxin-resistant, ESBL-producing, carbapenem-resistant Gram-negative human pathogens. PBT2 was observed to resensitize Klebsiella pneumoniae, Escherichia coli, Acinetobacter baumannii and Pseudomonas aeruginosa to last-resort polymyxin class antibiotics, including the less-toxic next-generation polymyxin derivative, FADDI-287. We were unable to select for mutants resistant to PBT2 + FADDI-287 in polymyxin resistant E. coli containing a plasmid-borne mcr-1 gene or K. pneumoniae carrying a chromosomal mgrB mutation. Using a highly invasive K. pneumoniae strain engineered for polymyxin resistance through mgrB mutation, we successfully demonstrated the efficacy of PBT2 + FADDI-287 in vivo for the treatment of Gram-negative sepsis. These data present a new treatment modality to break antibiotic resistance in high priority polymyxin-resistant Gram-negative pathogens.
Project description:The emergence and spread of polymyxin resistance, especially among Klebsiella pneumoniae isolates threaten the effective management of infections. This study profiled for polymyxin resistance mechanisms and investigated the activity of polymyxins plus vancomycin against carbapenem- and polymyxin-resistant K. pneumoniae.
Project description:This study aims to determine the epidemiology of Enterobacteriaceae resistant to antibiotics of last resort in pregnant women in labour at a tertiary hospital, Pretoria, South Africa. Rectal swabs shall be used to screen for colonisation with CRE and colistin-resistant Enterobacteriales in pregnant women during labour. Carbapenem and colistin-resistant Enterobacterales can cause the following infections: bacteraemia; nosocomial pneumonia; urinary tract infections, and intra-abdominal infections. Due to limited treatment options, infections caused by these multidrug-resistant organisms are associated with a mortality rate of 40-50%. Screening for colonisation of carbapenem-resistant Enterobacteriaceae (CRE) and colistin-resistant Enterobacteriaceae will help implement infection and prevention measures to limit the spread of these multidrug-resistant organisms.