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Liu H, Xiang Y, Xiong M, Xiao X, Zhou J, Tian H, Chen Q, Li Y. Prevalence of ST1049-KL5 carbapenem-resistant Klebsiella pneumoniae with a bla KPC-2 and bla NDM-1 co-carrying hypertransmissible IncM1 plasmid. Commun Biol 2024; 7:695. [PMID: 38844513 PMCID: PMC11156905 DOI: 10.1038/s42003-024-06398-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2023] [Accepted: 05/29/2024] [Indexed: 06/09/2024] Open
Abstract
Infection caused by KPC and NDM carbapenemases co-producing Klebsiella pneumoniae (KPC_NDM_CRKP) poses serious public health concerns. Here, we elucidate the prevalence of a hypertransmissible lncM1 plasmid, pKPC_NDM, co-carrying blaKPC-2 and blaNDM-1 genes in sequence type 1049 K_locus 5 (ST1049-KL5) KPC_NDM_CRKP isolates. Genetic and clonal relatedness analyses using pulsed-field gel electrophoresis, single nucleotide polymorphism analysis and core genome multilocus sequence typing suggested clonal dissemination of ST1049-KL5 KPC_NDM_CRKP strains in our hospital. Whole genome sequencing identified an identical 76,517 bp- blaKPC-2 and blaNDM-1 genes co-carrying IncM1 plasmid pKPC_NDM and a pLVPK-like hypervirulent plasmid in all ST1049-KL5 KPC_NDM_CRKP isolates. pKPC_NDM shared 100% identity with a previously sequenced plasmid CRKP35_unnamed4, demonstrating high transferability in conjugation assay, with conjugation frequencies reaching 10-4 and 10-5 in Escherichia coli and K. pneumoniae recipients, respectively. It also maintained favorable stability and flexible compatibility, with retention rates exceeding 80% after 10 days of continuous passage, and could be compatible with pre-existing blaKPC- or blaNDM-carrying plasmids in recipient strains. This study summarizes the characteristics of KPC_NDM_CRKP outbreaks and highlights the importance of ongoing surveillance and infection control strategies to address the challenges posed by ST1049 K. pneumoniae strains.
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Affiliation(s)
- Hongmao Liu
- Department of Laboratory Medicine, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Yating Xiang
- Department of Laboratory Medicine, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Mengyuan Xiong
- Department of Laboratory Medicine, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Xiao Xiao
- Department of Laboratory Medicine, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Junying Zhou
- Department of Laboratory Medicine, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Hongpan Tian
- Department of Laboratory Medicine, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Qingsong Chen
- Department of Laboratory Medicine, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Yirong Li
- Department of Laboratory Medicine, Zhongnan Hospital of Wuhan University, Wuhan, China.
- Hubei Engineering Center for Infectious Disease Prevention, Control and Treatment, Wuhan, China.
- Wuhan Research Center for Infectious Diseases and Tumors of the Chinese Academy of Medical Sciences, Wuhan, Hubei, China.
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Miliotis G, McDonagh F, Singh NK, O'Connor L, Tuohy A, Morris D, Venkateswaran K. Genomic analysis reveals the presence of emerging pathogenic Klebsiella lineages aboard the International Space Station. Microbiol Spectr 2023; 11:e0189723. [PMID: 37966203 PMCID: PMC10715203 DOI: 10.1128/spectrum.01897-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2023] [Accepted: 09/27/2023] [Indexed: 11/16/2023] Open
Abstract
IMPORTANCE The International Space Station (ISS) is a unique, hermetically sealed environment, subject to environmental pressures not encountered on Earth, including microgravity and radiation (cosmic ionising/UV). While bacteria's adaptability during spaceflight remains elusive, recent research suggests that it may be species and even clone-specific. Considering the documented spaceflight-induced suppression of the human immune system, a deper understanding of the genomics of potential human pathogens in space could shed light on species and lineages of medical astromicrobiological significance. In this study, we used hybrid assembly methods and comparative genomics to deliver a comprehensive genomic characterization of 10 Klebsiella isolates retrieved from the ISS. Our analysis unveiled that Klebsiella quasipneumoniae ST138 demonstrates both spatial and temporal persistence aboard the ISS, showing evidence of genomic divergence from its Earth-based ST138 lineage. Moreover, we characterized plasmids from Klebsiella species of ISS origin, which harbored genes for disinfectant resistance and enhanced thermotolerance, suggestin possible adaptive advantages. Furthermore, we identified a mobile genetic element containing a hypervirulence-associated locus belonging to a Klebsiella pneumoniae isolate of the "high-risk" ST101 clone. Our work provides insights into the adaptability and persistence of Klebsiella species during spaceflight, highlighting the importance of understanding the dynamics of potential pathogenic bacteria in such environments.
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Affiliation(s)
- Georgios Miliotis
- Antimicrobial Resistance and Microbial Ecology Group, School of Medicine, University of Galway, Galway, Ireland
| | - Francesca McDonagh
- Antimicrobial Resistance and Microbial Ecology Group, School of Medicine, University of Galway, Galway, Ireland
| | - Nitin Kumar Singh
- Biotechnology and Planetary Protection Group, NASA Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California, USA
| | - Louise O'Connor
- Antimicrobial Resistance and Microbial Ecology Group, School of Medicine, University of Galway, Galway, Ireland
| | - Alma Tuohy
- Antimicrobial Resistance and Microbial Ecology Group, School of Medicine, University of Galway, Galway, Ireland
| | - Dearbháile Morris
- Antimicrobial Resistance and Microbial Ecology Group, School of Medicine, University of Galway, Galway, Ireland
| | - Kasthuri Venkateswaran
- Biotechnology and Planetary Protection Group, NASA Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California, USA
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Recombinase-Aided Amplification Assay for Rapid Detection of Hypervirulent Klebsiella pneumoniae (hvKp) and Characterization of the hvKp Pathotype. Microbiol Spectr 2023:e0398422. [PMID: 36912637 PMCID: PMC10100362 DOI: 10.1128/spectrum.03984-22] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/14/2023] Open
Abstract
Hypervirulent Klebsiella pneumoniae (hvKp) is a major human pathogen associated with liver abscess, pneumonia, meningitis, and endophthalmitis. It is challenging to differentiate hvKp from classical Klebsiella pneumoniae (cKp) using conventional methods, necessitating the development of a rapid, sensitive, and convenient assay for hvKp detection. In this study, we constructed a recombinase-aided amplification (RAA) method targeting hvKp genes peg344 and rmpA, and also analyzed the pathogenic characteristics of hvKp. We optimized the reaction temperature and system, and evaluated its sensitivity, specificity, and clinical application. The primer and probe sets peg344-set1 and rmpA-set2 delivered significant fluorescent signals at 39°C with the shortest gene amplification times (sensitivity: 20 copies/reaction). This RAA assay showed no cross-reactivity with 15 other common pathogenic bacteria. Its applicability was confirmed by the evaluation of 208 clinical specimens, of which 45 were confirmed to be hvKp. The sensitivity and specificity of the RAA assay were both 100% compared with real-time PCR as the reference standard. To verify the assay, we also assessed the diversity of molecular characteristics among the hvKp isolates and identified serotype K1 and sequence type ST23 as the dominant clone. Virulence factors iroN and iutA were highly associated with virulence level. In conclusion, our novel RAA assay is a powerful tool for early diagnosis and epidemiological surveillance of hvKp. IMPORTANCEKlebsiella pneumoniae is the most common opportunistic bacterial species and a major threat to public health. Since the 1990s, hvKp has received increasing attention from public health officials and infectious disease specialists. Hypervirulent strains differ from classical strains in terms of phenotypic features and clinical outcomes. It is hard to identify hvKp from cKp using the conventional methods including colony morphology analysis, serum killing assays, mouse lethality assays, string tests, and real-time PCR. In this study, we established a rapid, sensitive and convenient recombinase-aided amplification assay for hvKp detection targeting virulence genes peg344 and rmpA. Our RAA assay provides an important tool for the rapid diagnosis of infectious diseases caused by hvKp, particularly in primary laboratories.
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Lan P, Lu Y, Yan R, Fang L, Zhao D, Jiang Y, Yu Y, Du X, Zhou J. Development of a Novel Typing Scheme Based on the Genetic Diversity of Heme/Hemin Uptake System Hmu in Klebsiella pneumoniae Species Complex. Microbiol Spectr 2023; 11:e0106222. [PMID: 36786624 PMCID: PMC10101058 DOI: 10.1128/spectrum.01062-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2022] [Accepted: 01/30/2023] [Indexed: 02/15/2023] Open
Abstract
Iron is essential for the survival and reproduction of Klebsiella pneumoniae. Although K. pneumoniae employs multiple types of siderophores to scavenge iron during infections, the majority of host iron is retained within erythrocytes and carried by hemoglobin that is inaccessible to siderophores. HmuRSTUV is a bacterial hemin/hemoprotein uptake system. However, the genetic background and function of HmuRSTUV in K. pneumoniae remain unknown. We collected 2,242 K. pneumoniae genomes, of which 2,218 (98.9%) had complete hmuRSTUV loci. Based on the 2,218 complete hmuRSTUV sequences, we established a novel typing scheme of K. pneumoniae named hmST, and 446 nonrepetitive hmSTs were identified. In hypervirulent lineages, hmST was diversely distributed and hmST1 mainly existed in ST23 strains. In contrast, hmST was less diversely distributed among multidrug-resistant strains. hmST demonstrated greater genetic diversity in hypervirulent lineages and community-acquired and bloodstream-sourced strains. In vitro and in vivo experiments revealed that an intact hmuRSTUV was essential for hemin uptake, playing an important role in bloodstream infections. This study established a novel typing scheme of hmST based on hmuRSTUV providing new insights into identifying and monitoring the emergence of novel virulence evolution in K. pneumoniae. IMPORTANCE Siderophore is a group of low molecular weight compounds with high affinity for ferric iron, which could facilitate bacterial iron consumption. Similarly, hemin/heme scavenged by the hemin uptake system HmuRSTUV usually act as another critical iron source for K. pneumoniae. This study proved that Hmu system significantly promoted the growth of K. pneumoniae in the presence of hemin and played an important role in bloodstream infections. A novel typing scheme named hmST was established, and the genetic diversity of hmuRSTUV loci was analyzed based on a large number of genomes. This study provides new insights into identifying and monitoring the emergence of novel virulence evolution in K. pneumoniae.
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Affiliation(s)
- Peng Lan
- Department of Critical Care Medicine, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, China
- Key Laboratory of Microbial Technology and Bioinformatics of Zhejiang Province, Hangzhou, China
| | - Ye Lu
- Department of Critical Care Medicine, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, China
- Key Laboratory of Microbial Technology and Bioinformatics of Zhejiang Province, Hangzhou, China
| | - Rushuang Yan
- Department of Critical Care Medicine, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, China
- Key Laboratory of Microbial Technology and Bioinformatics of Zhejiang Province, Hangzhou, China
| | - Lei Fang
- Department of Critical Care Medicine, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, China
- Key Laboratory of Microbial Technology and Bioinformatics of Zhejiang Province, Hangzhou, China
| | - Dongdong Zhao
- Key Laboratory of Microbial Technology and Bioinformatics of Zhejiang Province, Hangzhou, China
- Department of Infectious Diseases, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Yan Jiang
- Key Laboratory of Microbial Technology and Bioinformatics of Zhejiang Province, Hangzhou, China
- Department of Infectious Diseases, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Yunsong Yu
- Key Laboratory of Microbial Technology and Bioinformatics of Zhejiang Province, Hangzhou, China
- Department of Infectious Diseases, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Xiaoxing Du
- Key Laboratory of Microbial Technology and Bioinformatics of Zhejiang Province, Hangzhou, China
- Department of Infectious Diseases, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Jiancang Zhou
- Department of Critical Care Medicine, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, China
- Key Laboratory of Microbial Technology and Bioinformatics of Zhejiang Province, Hangzhou, China
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Peng W, Wu Y, Lu R, Zheng Y, Chen J, Pan P. Successful treatment of acute respiratory distress syndrome caused by hypervirulent Klebsiella pneumoniae with extracorporeal membrane oxygenation and continuous renal replacement therapy: A case report and literature review. Front Med (Lausanne) 2022; 9:936927. [PMID: 36091705 PMCID: PMC9449315 DOI: 10.3389/fmed.2022.936927] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2022] [Accepted: 07/29/2022] [Indexed: 11/29/2022] Open
Abstract
Hypervirulent Klebsiella pneumoniae (hvKP) causes invasive infections and leads to high morbidity and mortality rates. Here, we report the case of a Chinese man with diabetes mellitus who developed acute respiratory distress syndrome and septic shock due to hvKP belonging to the K1 strain. The patient was treated with venovenous extracorporeal membrane oxygenation and continuous renal replacement therapy, in combination with antibiotics and recovered well. Clinicians should be aware of fatal infections caused by hvKP and investigate the best treatment options for patients at various stages of infection.
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Affiliation(s)
- Wenzhong Peng
- Department of Respiratory Medicine, National Key Clinical Specialty, Branch of National Clinical Research Center for Respiratory Disease, Xiangya Hospital, Central South University, Changsha, China
- Center of Respiratory Medicine, Xiangya Hospital, Central South University, Changsha, China
- Clinical Research Center for Respiratory Diseases in Hunan Province, Xiangya Hospital, Central South University, Changsha, China
- Hunan Engineering Research Center for Intelligent Diagnosis and Treatment of Respiratory Disease, Xiangya Hospital, Central South University, Changsha, China
- National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, China
| | - Yanhao Wu
- Department of Respiratory Medicine, National Key Clinical Specialty, Branch of National Clinical Research Center for Respiratory Disease, Xiangya Hospital, Central South University, Changsha, China
- Center of Respiratory Medicine, Xiangya Hospital, Central South University, Changsha, China
- Clinical Research Center for Respiratory Diseases in Hunan Province, Xiangya Hospital, Central South University, Changsha, China
- Hunan Engineering Research Center for Intelligent Diagnosis and Treatment of Respiratory Disease, Xiangya Hospital, Central South University, Changsha, China
- National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, China
| | - Rongli Lu
- Department of Respiratory Medicine, National Key Clinical Specialty, Branch of National Clinical Research Center for Respiratory Disease, Xiangya Hospital, Central South University, Changsha, China
- Center of Respiratory Medicine, Xiangya Hospital, Central South University, Changsha, China
- Clinical Research Center for Respiratory Diseases in Hunan Province, Xiangya Hospital, Central South University, Changsha, China
- Hunan Engineering Research Center for Intelligent Diagnosis and Treatment of Respiratory Disease, Xiangya Hospital, Central South University, Changsha, China
- National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, China
| | - Yunpeng Zheng
- Department of Respiratory Medicine, National Key Clinical Specialty, Branch of National Clinical Research Center for Respiratory Disease, Xiangya Hospital, Central South University, Changsha, China
- Center of Respiratory Medicine, Xiangya Hospital, Central South University, Changsha, China
- Clinical Research Center for Respiratory Diseases in Hunan Province, Xiangya Hospital, Central South University, Changsha, China
- Hunan Engineering Research Center for Intelligent Diagnosis and Treatment of Respiratory Disease, Xiangya Hospital, Central South University, Changsha, China
- National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, China
| | - Jie Chen
- Department of Respiratory Medicine, National Key Clinical Specialty, Branch of National Clinical Research Center for Respiratory Disease, Xiangya Hospital, Central South University, Changsha, China
- Center of Respiratory Medicine, Xiangya Hospital, Central South University, Changsha, China
- Clinical Research Center for Respiratory Diseases in Hunan Province, Xiangya Hospital, Central South University, Changsha, China
- Hunan Engineering Research Center for Intelligent Diagnosis and Treatment of Respiratory Disease, Xiangya Hospital, Central South University, Changsha, China
- National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, China
| | - Pinhua Pan
- Department of Respiratory Medicine, National Key Clinical Specialty, Branch of National Clinical Research Center for Respiratory Disease, Xiangya Hospital, Central South University, Changsha, China
- Center of Respiratory Medicine, Xiangya Hospital, Central South University, Changsha, China
- Clinical Research Center for Respiratory Diseases in Hunan Province, Xiangya Hospital, Central South University, Changsha, China
- Hunan Engineering Research Center for Intelligent Diagnosis and Treatment of Respiratory Disease, Xiangya Hospital, Central South University, Changsha, China
- National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, China
- *Correspondence: Pinhua Pan
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Genomic and Immunological Characterization of Hypermucoviscous Carbapenem-Resistant Klebsiella pneumoniae ST25 Isolates from Northwest Argentina. Int J Mol Sci 2022; 23:ijms23137361. [PMID: 35806365 PMCID: PMC9266295 DOI: 10.3390/ijms23137361] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Revised: 06/14/2022] [Accepted: 06/27/2022] [Indexed: 02/05/2023] Open
Abstract
In recent years, an increase in the prevalence hypermucoviscous carbapenem-resistant Klebsiella pneumoniae with sequence type 25 (ST25) was detected in hospitals of Tucuman (Northwest Argentina). In this work, the virulence and the innate immune response to two K. pneumoniae ST25 strains (LABACER 01 and LABACER 27) were evaluated in a murine model after a respiratory challenge. In addition, comparative genomics was performed with K. pneumoniae LABACER01 and LABACER27 to analyze genes associated with virulence. Both LABACER01 and LABACER27 were detected in the lungs of infected mice two days after the nasal challenge, with LABACER01 counts significantly higher than those of LABACER27. Only LABACER01 was detected in hemocultures. Lactate dehydrogenase (LDH) and albumin levels in bronchoalveolar lavage (BAL) samples were significantly higher in mice challenged with LABACER01 than in LABACER27-infected animals, indicating greater lung tissue damage. Both strains increased the levels of neutrophils, macrophages, TNF-α, IL-1β, IL-6, KC, MCP-1, IFN-γ, and IL-17 in the respiratory tract and blood, with the effect of LABACER01 more marked than that of LABACER27. In contrast, LABACER27 induced higher levels of IL-10 in the respiratory tract than LABACER01. Genomic analysis revealed that K. pneumoniae LABACER01 and LABACER27 possess virulence factors found in other strains that have been shown to be hypervirulent, including genes required for enterobactin (entABCDEF) and salmochelin (iroDE) biosynthesis. In both strains, the genes of toxin–antitoxin systems, as well as regulators of the expression of virulence factors and adhesion genes were also detected. Studies on the genetic potential of multiresistant K. pneumoniae strains as well as their cellular and molecular interactions with the host are of fundamental importance to assess the association of certain virulence factors with the intensity of the inflammatory response. In this sense, this work explored the virulence profile based on genomic and in vivo studies of hypermucoviscous carbapenem-resistant K. pneumoniae ST25 strains, expanding the knowledge of the biology of the emerging ST25 clone in Argentina.
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Mohamed H, Marusich E, Afanasev Y, Leonov S. Bacterial Outer Membrane Permeability Increase Underlies the Bactericidal Effect of Fatty Acids From Hermetia illucens (Black Soldier Fly) Larvae Fat Against Hypermucoviscous Isolates of Klebsiella pneumoniae. Front Microbiol 2022; 13:844811. [PMID: 35602017 PMCID: PMC9121012 DOI: 10.3389/fmicb.2022.844811] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Accepted: 03/08/2022] [Indexed: 11/25/2022] Open
Abstract
Behind expensive treatments, Klebsiella pneumoniae infections account for extended hospitalization’s high mortality rates. This study aimed to evaluate the activity and mechanism of the antimicrobial action of a fatty acid-containing extract (AWME3) isolated from Hermetia illucens (HI) larvae fat against K. pneumoniae subsp. pneumoniae standard NDM-1 carbapenemase-producing ATCC BAA-2473 strain, along with a wild-type hypermucoviscous clinical isolate, strain K. pneumoniae subsp. pneumoniae KPi1627, and an environmental isolate, strain K. pneumoniae subsp. pneumoniae KPM9. We classified these strains as extensive multidrug-resistant (XDR) or multiple antibiotic-resistant (MDR) demonstrated by a susceptibility assay against 14 antibiotics belonging to ten classes of antibiotics. Antibacterial properties of fatty acids extracted from the HI larvae fat were evaluated using disk diffusion method, microdilution, minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), half of the inhibitory concentration (MIC50), and bactericidal assays. In addition, the cytotoxocity of AWME3 was tested on human HEK293 cells, and AWME3 lipid profile was determined by gas chromatography-mass spectrometry (GC-MS) analysis. For the first time, we demonstrated that the inhibition zone diameter (IZD) of fatty acid-containing extract (AWME3) of the HI larvae fat tested at 20 mg/ml was 16.52 ± 0.74 and 14.23 ± 0.35 mm against colistin-resistant KPi1627 and KPM9, respectively. It was 19.72 ± 0.51 mm against the colistin-susceptible K. pneumoniae ATCC BAA-2473 strain. The MIC and MBC were 250 μg/ml for all the tested bacteria strains, indicating the bactericidal effect of AWME3. The MIC50 values were 155.6 ± 0.009 and 160.1 ± 0.008 μg/ml against the KPi1627 and KPM9 isolates, respectively, and 149.5 ± 0.013 μg/ml against the ATCC BAA-2473 strain in the micro-dilution assay. For the first time, we demonstrated that AWME3 dose-dependently increased bacterial cell membrane permeability as determined by the relative electric conductivity (REC) of the K. pneumoniae ATCC BAA-2473 suspension, and that none of the strains did not build up resistance to extended AWME3 treatment using the antibiotic resistance assay. Cytotoxicity assay showed that AWME3 is safe for human HEK293 cells at IC50 266.1 μg/ml, while bactericidal for all the strains of bacteria at the same concentration. Free fatty acids (FFAs) and their derivatives were the significant substances among 33 compounds identified by the GC-MS analysis of AWME3. Cis-oleic and palmitoleic acids represent the most abundant unsaturated FAs (UFAs), while palmitic, lauric, stearic, and myristic acids were the most abundant saturated FAs (SFAs) of the AWME3 content. Bactericidal resistant-free AWM3 mechanism of action provides a rationale interpretations and the utility of HI larvae fat to develop natural biocidal resistance-free formulations that might be promising therapeutic against Gram-negative MDR bacteria causing nosocomial infections.
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Affiliation(s)
- Heakal Mohamed
- School of Biological and Medical Physics, Moscow Institute of Physics and Technology, Dolgoprudny, Russia
| | - Elena Marusich
- School of Biological and Medical Physics, Moscow Institute of Physics and Technology, Dolgoprudny, Russia
- *Correspondence: Elena Marusich,
| | - Yuriy Afanasev
- School of Biological and Medical Physics, Moscow Institute of Physics and Technology, Dolgoprudny, Russia
| | - Sergey Leonov
- School of Biological and Medical Physics, Moscow Institute of Physics and Technology, Dolgoprudny, Russia
- Institute of Cell Biophysics, Russian Academy of Sciences, Moscow, Russia
- Sergey Leonov,
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