Project description:With the global increase in the use of carbapenems, several gram-negative bacteria have acquired carbapenem resistance, thereby limiting treatment options. Klebsiella pneumoniae is one of such notorious pathogen that is being widely studied to find novel resistance mechanisms and drug targets. These antibiotic-resistant clinical isolates generally harbor many genetic alterations, and identification of causal mutations will provide insights into the molecular mechanisms of antibiotic resistance. We propose a method to prioritize mutated genes responsible for antibiotic resistance, in which mutated genes that also show significant expression changes among their functionally coupled genes become more likely candidates. For network-based analyses, we developed a genome-scale co-functional network of K. pneumoniae genes, KlebNet (www.inetbio.org/klebnet). Using KlebNet, we could reconstruct functional modules for antibiotic-resistance, and virulence, and retrieved functional association between them. With complementation assays with top candidate genes, we could validate a gene for negative regulation of meropenem resistance and four genes for positive regulation of virulence in Galleria mellonella larvae. Therefore, our study demonstrated the feasibility of network-based identification of genes required for antimicrobial resistance and virulence of human pathogenic bacteria with genomic and transcriptomic profiles from antibiotic-resistant clinical isolates.
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:There is an urgent need for novel antibiotics against carbapenem and 3rd generation cephalosporin-resistant Gram-negative pathogens, for which the last-resort antibiotics have lost most of their efficacy. We describe here a novel class of synthetic antibiotics that was inspired from natural product-derived scaffolds. The antibiotics have an unprecedented mechanism of action, which targets the main component (BamA) of the Bam folding machinery required for folding and insertion of ß-barrel proteins into the outer membrane of Gram-negative bacteria. This OMPTA (outer membrane protein-targeting antibiotic) class shows potent activity against multidrug-resistant Gram-negative ESKAPE pathogens and overcomes colistin-resistance both in vitro and in vivo. A clinical candidate has the potential to address life threatening Gram-negative infections with high unmet medical need.
Project description:There is an urgent need for novel antibiotics against carbapenem and 3rd generation cephalosporin-resistant Gram-negative pathogens, for which the last-resort antibiotics have lost most of their efficacy. We describe here a novel class of synthetic antibiotics that was inspired from natural product-derived scaffolds. The antibiotics have an unprecedented mechanism of action, which targets the main component (BamA) of the Bam folding machinery required for folding and insertion of ß-barrel proteins into the outer membrane of Gram-negative bacteria. This OMPTA (outer membrane protein-targeting antibiotic) class shows potent activity against multidrug-resistant Gram-negative ESKAPE pathogens and overcomes colistin-resistance both in vitro and in vivo. A clinical candidate has the potential to address life threatening Gram-negative infections with high unmet medical need.
2020-02-04 | MSV000084899 | MassIVE
Project description:Whole genome sequencing of carbapenem resistant Enterobacteriaceae clinical isolates