scholarly journals Genome-Wide Screening for Enteric Colonization Factors in Carbapenem-Resistant ST258 Klebsiella pneumoniae

mBio ◽  
2019 ◽  
Vol 10 (2) ◽  
Author(s):  
Hea-Jin Jung ◽  
Eric R. Littmann ◽  
Ruth Seok ◽  
Ingrid M. Leiner ◽  
Ying Taur ◽  
...  
Keyword(s):  
Klebsiella Pneumoniae ◽  
Genetic Factors ◽  
Intestinal Lumen ◽  
Intestinal Colonization ◽  
Antibiotic Resistant ◽  
Content Type ◽  
Carbapenem Resistant ◽  
Gut Colonization ◽  
Colonization Factors

ABSTRACT A diverse, antibiotic-naive microbiota prevents highly antibiotic-resistant microbes, including carbapenem-resistant Klebsiella pneumoniae (CR-Kp), from achieving dense colonization of the intestinal lumen. Antibiotic-mediated destruction of the microbiota leads to expansion of CR-Kp in the gut, markedly increasing the risk of bacteremia in vulnerable patients. While preventing dense colonization represents a rational approach to reduce intra- and interpatient dissemination of CR-Kp, little is known about pathogen-associated factors that enable dense growth and persistence in the intestinal lumen. To identify genetic factors essential for dense colonization of the gut by CR-Kp, we constructed a highly saturated transposon mutant library with >150,000 unique mutations in an ST258 strain of CR-Kp and screened for in vitro growth and in vivo intestinal colonization in antibiotic-treated mice. Stochastic and partially reversible fluctuations in the representation of different mutations during dense colonization revealed the dynamic nature of intestinal microbial populations. We identified genes that are crucial for early and late stages of dense gut colonization and confirmed their role by testing isogenic mutants in in vivo competition assays with wild-type CR-Kp. Screening of the transposon library also identified mutations that enhanced in vivo CR-Kp growth. These newly identified colonization factors may provide novel therapeutic opportunities to reduce intestinal colonization by CR-Kp. IMPORTANCE Klebsiella pneumoniae is a common cause of bloodstream infections in immunocompromised and hospitalized patients, and over the last 2 decades, some strains have acquired resistance to nearly all available antibiotics, including broad-spectrum carbapenems. The U.S. Centers for Disease Control and Prevention has listed carbapenem-resistant K. pneumoniae (CR-Kp) as an urgent public health threat. Dense colonization of the intestine by CR-Kp and other antibiotic-resistant bacteria is associated with an increased risk of bacteremia. Reducing the density of gut colonization by CR-Kp is likely to reduce their transmission from patient to patient in health care facilities as well as systemic infections. How CR-Kp expands and persists in the gut lumen, however, is poorly understood. Herein, we generated a highly saturated mutant library in a multidrug-resistant K. pneumoniae strain and identified genetic factors that are associated with dense gut colonization by K. pneumoniae. This study sheds light on host colonization by K. pneumoniae and identifies potential colonization factors that contribute to high-density persistence of K. pneumoniae in the intestine.

scholarly journals Fighting Antibiotic-Resistant Klebsiella pneumoniae with “Sweet” Immune Targets

mBio ◽  
2018 ◽  
Vol 9 (3) ◽  
Author(s):  
Roberto Adamo ◽  
Immaculada Margarit
Keyword(s):  
Klebsiella Pneumoniae ◽  
Multidrug Resistant ◽  
Resistant Bacteria ◽  
Therapeutic Approaches ◽  
Antibiotic Resistant ◽  
Content Type ◽  
Carbapenem Resistant ◽  
Surface Polysaccharides ◽  
Resistant Strains ◽  
Murine Monoclonal Antibodies

ABSTRACT Antibiotics and vaccines have greatly impacted human health in the last century by dramatically reducing the morbidity and mortality associated with infectious diseases. The recent challenge posed by the emergence of multidrug-resistant bacteria could possibly be addressed by novel immune prophylactic and therapeutic approaches. Among the newly threatening pathogens, Klebsiella pneumoniae is particularly worrisome in the nosocomial setting, and its surface polysaccharides are regarded as promising antigen candidates. The majority of Klebsiella carbapenem-resistant strains belong to the sequence type 158 (ST258) lineage, with two main clades expressing capsular polysaccharides CPS1 and CPS2. In a recent article, S. D. Kobayashi and colleagues (mBio 9:e00297-18, 2018, https://doi.org/10.1128/mBio.00297-18) show that CPS2-specific IgGs render ST258 clade 2 bacteria more sensitive to human serum and phagocytic killing. E. Diago-Navarro et al. (mBio 9:e00091-18, 2018, https://doi.org/10.1128/mBio.00091-18) generated two murine monoclonal antibodies recognizing distinct glycotopes of CPS2 that presented functional activity against multiple ST258 strains. These complementary studies represent a step toward the control of this dangerous pathogen.

scholarly journals In Vivo Efficacy of Novel Monobactam LYS228 in Murine Models of Carbapenemase-Producing Klebsiella pneumoniae Infection

2019 ◽  
Vol 63 (4) ◽  
Author(s):  
W. J. Weiss ◽  
M. E. Pulse ◽  
P. Nguyen ◽  
E. J. Growcott
Keyword(s):  
Klebsiella Pneumoniae ◽  
Clinical Development ◽  
Murine Models ◽  
Bacterial Burden ◽  
In Vivo Efficacy ◽  
Content Type ◽  
Carbapenem Resistant ◽  
Infection Models ◽  
Resistant Strains

ABSTRACT LYS228 has potent antibacterial activity against carbapenem-resistant strains of Enterobacteriaceae. LYS228 was efficacious in neutropenic thigh models established with Klebsiella pneumoniae producing KPC-2 or NDM-1; pretreatment with uranyl nitrate considerably shifted calculated static doses of LYS228. In murine ascending pyelonephritis, LYS228 reduced bacterial burden in kidney, urine, and bladder. The successful treatment of murine infection models established with carbapenem-resistant K. pneumoniae further supports the clinical development of LYS228.

scholarly journals Molecular Characterization of Carbapenemase-Producing Escherichia coli and Klebsiella pneumoniae in the Countries of the Gulf Cooperation Council: Dominance of OXA-48 and NDM Producers

2014 ◽  
Vol 58 (6) ◽  
pp. 3085-3090 ◽  
Author(s):  
Hosam M. Zowawi ◽  
Anna L. Sartor ◽  
Hanan H. Balkhy ◽  
Timothy R. Walsh ◽  
Sameera M. Al Johani ◽  
...  
Keyword(s):  
Klebsiella Pneumoniae ◽  
United Arab Emirates ◽  
Gulf Cooperation Council ◽  
Mechanisms Of Resistance ◽  
Antibiotic Resistant ◽  
Content Type ◽  
Carbapenem Resistant ◽  
Resistant Genes ◽  
Gcc Countries

ABSTRACTThe molecular epidemiology and mechanisms of resistance of carbapenem-resistantEnterobacteriaceae(CRE) were determined in hospitals in the countries of the Gulf Cooperation Council (GCC), namely, Saudi Arabia, United Arab Emirates, Oman, Qatar, Bahrain, and Kuwait. Isolates were subjected to PCR-based detection of antibiotic-resistant genes and repetitive sequence-based PCR (rep-PCR) assessments of clonality. Sixty-two isolates which screened positive for potential carbapenemase production were assessed, and 45 were found to produce carbapenemase. The most common carbapenemases were of the OXA-48 (35 isolates) and NDM (16 isolates) types; 6 isolates were found to coproduce the OXA-48 and NDM types. No KPC-type, VIM-type, or IMP-type producers were detected. Multiple clones were detected with seven clusters of clonally relatedKlebsiella pneumoniae. Awareness of CRE in GCC countries has important implications for controlling the spread of CRE in the Middle East and in hospitals accommodating patients transferred from the region.

scholarly journals Serum Antibody Responses against Carbapenem-Resistant Klebsiella pneumoniae in Infected Patients

mSphere ◽  
2021 ◽  
Vol 6 (2) ◽  
Author(s):  
Kasturi Banerjee ◽  
Michael P. Motley ◽  
Elizabeth Diago-Navarro ◽  
Bettina C. Fries
Keyword(s):  
Klebsiella Pneumoniae ◽  
Capsular Polysaccharide ◽  
Serum Antibody ◽  
Antibody Responses ◽  
Capsular Polysaccharides ◽  
Content Type ◽  
Carbapenem Resistant ◽  
Reactive Properties

ABSTRACT Capsular polysaccharide (CPS) heterogeneity within carbapenem-resistant Klebsiella pneumoniae (CR-Kp) strain sequence type 258 (ST258) must be considered when developing CPS-based vaccines. Here, we sought to characterize CPS-specific antibody responses elicited by CR-Kp-infected patients. Plasma and bacterial isolates were collected from 33 hospital patients with positive CR-Kp cultures. Isolate capsules were typed by wzi sequencing. Reactivity and measures of efficacy of patient antibodies were studied against 3 prevalent CR-Kp CPS types (wzi29, wzi154, and wzi50). High IgG titers against wzi154 and wzi50 CPS were documented in 79% of infected patients. Patient-derived (PD) IgGs agglutinated CR-Kp and limited growth better than naive IgG and promoted phagocytosis of strains across the serotype isolated from their donors. Additionally, poly-IgG from wzi50 and wzi154 patients promoted phagocytosis of nonconcordant CR-Kp serotypes. Such effects were lost when poly-IgG was depleted of CPS-specific IgG. Additionally, mice infected with wzi50, wzi154, and wzi29 CR-Kp strains preopsonized with wzi50 patient-derived IgG exhibited lower lung CFU than controls. Depletion of wzi50 antibodies (Abs) reversed this effect in wzi50 and wzi154 infections, whereas wzi154 Ab depletion reduced poly-IgG efficacy against wzi29 CR-Kp. We are the first to report cross-reactive properties of CPS-specific Abs from CR-Kp patients through both in vitro and in vivo models. IMPORTANCE Carbapenem-resistant Klebsiella pneumoniae is a rapidly emerging public health threat that can cause fatal infections in up to 50% of affected patients. Due to its resistance to nearly all antimicrobials, development of alternate therapies like antibodies and vaccines is urgently needed. Capsular polysaccharides constitute important targets, as they are crucial for Klebsiella pneumoniae pathogenesis. Capsular polysaccharides are very diverse and, therefore, studying the host’s capsule-type specific antibodies is crucial to develop effective anti-CPS immunotherapies. In this study, we are the first to characterize humoral responses in infected patients against carbapenem-resistant Klebsiella pneumoniae expressing different wzi capsule types. This study is the first to report the efficacy of cross-reactive properties of CPS-specific Abs in both in vitro and in vivo models.

scholarly journals Anticolonization of Carbapenem-Resistant Klebsiella pneumoniae by Lactobacillus plantarum LP1812 Through Accumulated Acetic Acid in Mice Intestinal

2021 ◽  
Vol 11 ◽  
Author(s):  
Rushuang Yan ◽  
Ye Lu ◽  
Xiaoqing Wu ◽  
Peihao Yu ◽  
Peng Lan ◽  
...  
Keyword(s):  
Acetic Acid ◽  
Klebsiella Pneumoniae ◽  
Lactobacillus Plantarum ◽  
Intestinal Lumen ◽  
Pathway Enrichment Analysis ◽  
Potential Candidate ◽  
Carbapenem Resistant ◽  
Gut Colonization ◽  
16S Rna

Carbapenem-resistant Klebsiella pneumoniae (CRKP) is highly prevalent and poses a significant threat to public health. In critically ill patients, gut colonization is considered to be the reservoir of recurrent CRKP infection. Therefore, eliminating CRKP carriage in the intestine is critical for preventing subsequent CRKP infection. In the present study, Lactobacillus plantarum LP1812, a probiotic that can inhibit CRKP in vitro, was used as a candidate probiotic to investigate its efficacy for CRKP anticolonization. Compared with the control, mice fed with 1×10 8 CFU L. plantarum LP1812 exhibited significant CRKP clearance from 1×10 4 CFU/mg to less than 10 CFU/mg in mice feces. Furthermore, 16S RNA gene sequencing revealed that L. plantarum LP1812 modulated mice microbiota by increasing the relative abundance of the genus Halomanas, Blautia, and Holdemania. Further KEGG pathway enrichment analysis revealed that fatty acid-utilizing bacteria, such as acetate-producing Bacteroidetes and Blautia flourished in mice fed with L. plantarum LP1812. Moreover, we found that the concentration of acetic acid was higher in L. plantarum LP1812, which inhibited the growth of K. pneumoniae strains in vitro. Meanwhile, mice intragastrically administered with acetic acid exhibited significantly increased CRKP elimination in vivo. In conclusion, L. plantarum LP1812 is a potential candidate for intestinal CRKP anticolonization by regulating the intestinal microbiota and inhibiting CRKP via increased acetic acid in the intestinal lumen.

scholarly journals Complete Genome Sequence of Shelby, a Siphophage Infecting Carbapenemase-Producing Klebsiella pneumoniae

2019 ◽  
Vol 8 (38) ◽  
Author(s):  
Robert Saldana ◽  
Heather Newkirk ◽  
Mei Liu ◽  
Jason J. Gill ◽  
Jolene Ramsey
Keyword(s):  
Klebsiella Pneumoniae ◽  
Genome Sequence ◽  
Nosocomial Infections ◽  
Complete Genome Sequence ◽  
Complete Genome ◽  
Antibiotic Resistant ◽  
Content Type ◽  
Carbapenem Resistant ◽  
The Family ◽  
Predicted Function

Carbapenem-resistant Klebsiella pneumoniae, a bacterium of the family Enterobacteriaceae, is a high-priority antibiotic-resistant pathogen that causes nosocomial infections. Here, we describe the isolation and annotation of the K. pneumoniae siphophage Shelby, a T1-like siphophage encoding 78 proteins, of which 34 have a predicted function.

scholarly journals MCR-1 and OXA-48 In Vivo Acquisition in KPC-Producing Escherichia coli after Colistin Treatment

2017 ◽  
Vol 61 (8) ◽  
Author(s):  
Racha Beyrouthy ◽  
Frederic Robin ◽  
Aude Lessene ◽  
Igor Lacombat ◽  
Laurent Dortet ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Klebsiella Pneumoniae ◽  
Whole Genome Sequencing ◽  
Genome Sequencing ◽  
Whole Genome ◽  
Content Type ◽  
First Report ◽  
E Coli ◽  
Carbapenem Resistant

ABSTRACT The spread of mcr-1-encoding plasmids into carbapenem-resistant Enterobacteriaceae raises concerns about the emergence of untreatable bacteria. We report the acquisition of mcr-1 in a carbapenem-resistant Escherichia coli strain after a 3-week course of colistin in a patient repatriated to France from Portugal. Whole-genome sequencing revealed that the Klebsiella pneumoniae carbapenemase-producing E. coli strain acquired two plasmids, an IncL OXA-48-encoding plasmid and an IncX4 mcr-1-encoding plasmid. This is the first report of mcr-1 in carbapenemase-encoding bacteria in France.

scholarly journals Four Carbapenem-Resistant Gram-Negative Species Carrying Distinct Carbapenemases in a Single Patient

2014 ◽  
Vol 53 (3) ◽  
pp. 1031-1033 ◽  
Author(s):  
Baixing Ding ◽  
Fupin Hu ◽  
Yang Yang ◽  
Qinglan Guo ◽  
Jinwei Huang ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Klebsiella Pneumoniae ◽  
Acinetobacter Baumannii ◽  
Enterobacter Aerogenes ◽  
Single Patient ◽  
Gram Negative ◽  
Content Type ◽  
E Coli ◽  
Carbapenem Resistant

Carbapenem-resistantEscherichia coli,Klebsiella pneumoniae,Enterobacter aerogenes, andAcinetobacter baumanniiwere isolated from a single patient, each producing different carbapenemases (NDM-1, KPC-2, IMP, and OXA-23, respectively). The NDM-1-producingE. colistrain was preceded by a clonally related carbapenem-susceptible strain a month earlier, suggestingin vivoacquisition ofblaNDM-1.

scholarly journals Komodo-dragon cathelicidin-inspired peptides are antibacterial against carbapenem-resistant Klebsiella pneumoniae

2020 ◽  
Vol 69 (11) ◽  
pp. 1262-1272
Author(s):  
Samantha J. Hitt ◽  
Barney M. Bishop ◽  
Monique L. van Hoek
Keyword(s):  
Antimicrobial Activity ◽  
Klebsiella Pneumoniae ◽  
Antimicrobial Peptides ◽  
Galleria Mellonella ◽  
Content Type ◽  
Carbapenem Resistant ◽  
Level Of Activity ◽  
Improvement In Survival ◽  
Synthetic Antimicrobial Peptides

Introduction. The rise of carbapenem-resistant enterobacteriaceae (CRE) is a growing crisis that requires development of novel therapeutics. Hypothesis. To this end, cationic antimicrobial peptides (CAMPs) represent a possible source of new potential therapeutics to treat difficult pathogens such as carbapenem-resistant Klebsiella pneumoniae (CRKP), which has gained resistance to many if not all currently approved antibiotics, making treatment difficult. Aim. To examine the anti-CRKP antimicrobial activity of the predicted cathelicidins derived from Varanus komodoensis (Komodo dragon) as well as synthetic antimicrobial peptides that we created. Methodology. We determined the minimum inhibitory concentrations of the peptides against CRKP. We also characterized the abilities of these peptides to disrupt the hyperpolarization of the bacterial membrane as well as their ability to form pores in the membrane. Results. We did not observe significant anti-CRKP activity for the predicted native Komodo cathelicidin peptides. We found that the novel peptides DRGN-6,-7 and -8 displayed significant antimicrobial activity against CRKP with MICs of 4–8 µg ml−1. DRGN-6 peptide was the most effective peptide against CRKP. Unfortunately, these peptides showed higher than desired levels of hemolysis, although in vivo testing in the waxworm Galleria mellonella showed no mortality associated with treatment by the peptide; however, CRKP-infected waxworms treated with peptide did not show an improvement in survival. Conclusion. Given the challenges of treating CRKP, identification of peptides with activity against it represents a promising avenue for further research. Given DRGN-6′s similar level of activity to colistin, DRGN-6 is a promising template for the development of novel antimicrobial peptide-based therapeutics.

scholarly journals Severe Sepsis Facilitates Intestinal Colonization by Extended-Spectrum-β-Lactamase-Producing Klebsiella pneumoniae and Transfer of the SHV-18 Resistance Gene to Escherichia coli during Antimicrobial Treatment

2013 ◽  
Vol 58 (2) ◽  
pp. 1039-1046 ◽  
Author(s):  
Jun Guan ◽  
Shaoze Liu ◽  
Zhaofen Lin ◽  
Wenfang Li ◽  
Xuefeng Liu ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Severe Sepsis ◽  
Klebsiella Pneumoniae ◽  
Resistance Gene ◽  
Antimicrobial Treatment ◽  
Intestinal Colonization ◽  
Content Type ◽  
Challenge Strain ◽  
Gut Colonization ◽  
Extended Spectrum

ABSTRACTInfections caused by multidrug-resistant pathogens are frequent and life threatening in critically ill patients. To investigate whether severe sepsis affects gut colonization by resistant pathogens and genetic exchange between opportunistic pathogens, we tested the intestinal-colonization ability of an extended-spectrum beta-lactamase-producingKlebsiella pneumoniaestrain carrying the SHV-18 resistance gene and the transfer ability of the resistance gene to endogenousEscherichia coliunder ceftriaxone treatment in rats with burn injury only or severe sepsis induced by burns plus endotoxin exposure. Without ceftriaxone treatment, theK. pneumoniaestrain colonized the intestine in both septic and burned rats for a short time, with clearance occurring earlier in burn-only rats but never in sham burn rats. In both burned and septic rats, the colonization level of the challenge strain dropped at the beginning and then later increased during ceftriaxone treatment, after which it declined gradually. This pattern coincided with the change in resistance ofK. pneumoniaeto ceftriaxone during and after ceftriaxone treatment. Compared with burn-only injury, severe sepsis had a more significant effect on the change in antimicrobial resistance to ceftriaxone. Only in septic rats was the resistance gene successfully transferred from the challenge strain to endogenousE. coliduring ceftriaxone treatment; the gene persisted for at least 4 weeks after ceftriaxone treatment. We concluded that severe sepsis can facilitate intestinal colonization by an exogenous resistant pathogen and the transfer of the resistance gene to a potential endogenous pathogen during antimicrobial treatment.

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