{"database":"biostudies-literature","file_versions":[],"scores":null,"additional":{"submitter":["Kong J"],"funding":["Key Laboratory of Clinical Laboratory Diagnosis and Translational Research of Zhejiang Province"],"pagination":["183"],"full_dataset_link":["https://www.ebi.ac.uk/biostudies/studies/S-EPMC11956232"],"repository":["biostudies-literature"],"omics_type":["Unknown"],"volume":["25(1)"],"pubmed_abstract":["Background
Carbapenem-resistant Escherichia coli (CREC) is one of the most significant clinical pathogens, primarily emerging owing to the widespread use of broad-spectrum antibiotics. Antimicrobial resistance is a major global health challenge that prolongs treatment duration and increases healthcare costs. This study evaluated the antibacterial and anti-inflammatory effects of the antimicrobial peptide Lf-KR against CREC.Methods
Broth microdilution method, growth curve analysis, and time-kill assays were performed to evaluate the antibacterial activity of Lf-KR against CREC. The working mechanism of Lf-KR was elucidated using N-phenyl-1-naphthylamine, propidium iodide fluorochrome, and lipopolysaccharide-binding assays. qRT-PCR was used to assess the peptide's effects on the expression of pro-inflammatory cytokines expression during infection. Furthermore, the safety and stability of Lf-KR were assessed by testing its cytotoxicity, hemolytic activity, and antibacterial stability under various conditions. The Galleria mellonella infection model was applied to evaluate the in vivo activity of Lf-KR.Results
In vitro tests showed that Lf-KR exhibited potent antibacterial activity against CREC, with the minimum inhibitory concentrations of ranging from 4-8 µg/mL and minimum bactericidal concentrations 4-16 µg/mL. Mechanistically, Lf-KR induced bacterial cell death by disrupting the bacterial membrane. Furthermore, Lf-KR significantly reduced the expression of pro-inflammatory cytokine genes, including IL-1β, IL-6, and TNF-α, in RAW 264.7 macrophage cells infected with CREC. Lf-KR concentrations < 128 µg/mL showed no significant cytotoxicity or erythrocyte hemolytic activity. Lf-KR antibacterial activity was stable across a wide temperature range (- 80 °C to 65 °C), although it was more susceptible to inhibition by fetal bovine serum. The G. mellonella infection model further demonstrated the robust antimicrobial activity of Lf-KR.Conclusions
This study demonstrated that the antimicrobial peptide Lf-KR is a highly promising antimicrobial and anti-inflammatory agent against CREC, with potential applications in combating multi drug-resistant bacterial infections."],"journal":["BMC microbiology"],"pubmed_title":["Antimicrobial and anti-inflammatory effects of antimicrobial peptide Lf-KR against carbapenem-resistant Escherichia coli."],"pmcid":["PMC11956232"],"funding_grant_id":["2022E10022"],"pubmed_authors":["Liu Y","Zheng J","Zhang X","Zhou B","Chen W","Zhou T","Han Y","Kong J","Wang Y","Zhou H"],"additional_accession":[]},"is_claimable":false,"name":"Antimicrobial and anti-inflammatory effects of antimicrobial peptide Lf-KR against carbapenem-resistant Escherichia coli.","description":"Background
Carbapenem-resistant Escherichia coli (CREC) is one of the most significant clinical pathogens, primarily emerging owing to the widespread use of broad-spectrum antibiotics. Antimicrobial resistance is a major global health challenge that prolongs treatment duration and increases healthcare costs. This study evaluated the antibacterial and anti-inflammatory effects of the antimicrobial peptide Lf-KR against CREC.Methods
Broth microdilution method, growth curve analysis, and time-kill assays were performed to evaluate the antibacterial activity of Lf-KR against CREC. The working mechanism of Lf-KR was elucidated using N-phenyl-1-naphthylamine, propidium iodide fluorochrome, and lipopolysaccharide-binding assays. qRT-PCR was used to assess the peptide's effects on the expression of pro-inflammatory cytokines expression during infection. Furthermore, the safety and stability of Lf-KR were assessed by testing its cytotoxicity, hemolytic activity, and antibacterial stability under various conditions. The Galleria mellonella infection model was applied to evaluate the in vivo activity of Lf-KR.Results
In vitro tests showed that Lf-KR exhibited potent antibacterial activity against CREC, with the minimum inhibitory concentrations of ranging from 4-8 µg/mL and minimum bactericidal concentrations 4-16 µg/mL. Mechanistically, Lf-KR induced bacterial cell death by disrupting the bacterial membrane. Furthermore, Lf-KR significantly reduced the expression of pro-inflammatory cytokine genes, including IL-1β, IL-6, and TNF-α, in RAW 264.7 macrophage cells infected with CREC. Lf-KR concentrations < 128 µg/mL showed no significant cytotoxicity or erythrocyte hemolytic activity. Lf-KR antibacterial activity was stable across a wide temperature range (- 80 °C to 65 °C), although it was more susceptible to inhibition by fetal bovine serum. The G. mellonella infection model further demonstrated the robust antimicrobial activity of Lf-KR.Conclusions
This study demonstrated that the antimicrobial peptide Lf-KR is a highly promising antimicrobial and anti-inflammatory agent against CREC, with potential applications in combating multi drug-resistant bacterial infections.","dates":{"release":"2025-01-01T00:00:00Z","publication":"2025 Mar","modification":"2025-07-02T03:04:47.948Z","creation":"2025-07-02T03:04:47.948Z"},"accession":"S-EPMC11956232","cross_references":{"pubmed":["40165061"],"doi":["10.1186/s12866-025-03906-8"]}}