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Cell Metabolism Apr 2023Estradiol decline can result in depressive disorders in females; nevertheless, the causes of this decline are unclear. In this study, we isolated estradiol-degrading...
Estradiol decline can result in depressive disorders in females; nevertheless, the causes of this decline are unclear. In this study, we isolated estradiol-degrading Klebsiella aerogenes from the feces of premenopausal females with depression. In mice, gavaging with this strain led to estradiol decline and depression-like behaviors. The gene encoding the estradiol-degrading enzyme in K. aerogenes was identified as 3β-hydroxysteroid dehydrogenase (3β-HSD). Heterologously expressing 3β-HSD resulted in Escherichia coli obtaining the ability to degrade estradiol. Gavaging mice with 3β-HSD-expressing E. coli decreased their serum estradiol levels, causing depression-like behaviors. The prevalence of K. aerogene and 3β-HSD was higher in premenopausal women with depression than in those without depression. These results suggest that the estradiol-degrading bacteria and 3β-HSD enzymes are potential intervention targets for depression treatment in premenopausal women.
Topics: Adult; Animals; Female; Humans; Mice; 3-Hydroxysteroid Dehydrogenases; Depression; Enterobacter aerogenes; Escherichia coli; Estradiol; Feces; Microbiota; Premenopause
PubMed: 36933555
DOI: 10.1016/j.cmet.2023.02.017 -
Journal of Clinical Microbiology Aug 2020was recently renamed This study aimed to identify differences in clinical characteristics, outcomes, and bacterial genetics among patients with versus species...
Newly Named Klebsiella aerogenes (formerly Enterobacter aerogenes) Is Associated with Poor Clinical Outcomes Relative to Other Species in Patients with Bloodstream Infection.
was recently renamed This study aimed to identify differences in clinical characteristics, outcomes, and bacterial genetics among patients with versus species bloodstream infections (BSI). We prospectively enrolled patients with or complex () BSI from 2002 to 2015. We performed whole-genome sequencing (WGS) and pan-genome analysis on all bacteria. Overall, 150 patients with (46/150 [31%]) or (104/150 [69%]) BSI were enrolled. The two groups had similar baseline characteristics. Neither total in-hospital mortality (13/46 [28%] versus 22/104 [21%]; = 0.3) nor attributable in-hospital mortality (9/46 [20%] versus 13/104 [12%]; = 0.3) differed between patients with versus BSI, respectively. However, poor clinical outcome (death before discharge, recurrent BSI, and/or BSI complication) was higher for than BSI (32/46 [70%] versus 42/104 [40%]; = 0.001). In a multivariable regression model, BSI, relative to BSI, was predictive of poor clinical outcome (odds ratio 3.3; 95% confidence interval 1.4 to 8.1; = 0.008). Pan-genome analysis revealed 983 genes in 323 genomic islands unique to isolates, including putative virulence genes involved in iron acquisition ( = 67), fimbriae/pili/flagella production ( = 117), and metal homeostasis ( = 34). Antibiotic resistance was largely found in lineage 1, which had a higher rate of multidrug resistant phenotype (23/54 [43%]) relative to all other bacterial isolates (23/96 [24%]; = 0.03). BSI was associated with poor clinical outcomes relative to BSI. Putative virulence factors in may account for these differences.
Topics: Anti-Bacterial Agents; Bacteremia; Enterobacter; Enterobacter aerogenes; Humans; Sepsis
PubMed: 32493786
DOI: 10.1128/JCM.00582-20 -
Frontiers in Microbiology 2015Enterobacter aerogenes and E. cloacae have been reported as important opportunistic and multiresistant bacterial pathogens for humans during the last three decades in... (Review)
Review
Enterobacter aerogenes and E. cloacae have been reported as important opportunistic and multiresistant bacterial pathogens for humans during the last three decades in hospital wards. These Gram-negative bacteria have been largely described during several outbreaks of hospital-acquired infections in Europe and particularly in France. The dissemination of Enterobacter sp. is associated with the presence of redundant regulatory cascades that efficiently control the membrane permeability ensuring the bacterial protection and the expression of detoxifying enzymes involved in antibiotic degradation/inactivation. In addition, these bacterial species are able to acquire numerous genetic mobile elements that strongly contribute to antibiotic resistance. Moreover, this particular fitness help them to colonize several environments and hosts and rapidly and efficiently adapt their metabolism and physiology to external conditions and environmental stresses. Enterobacter is a versatile bacterium able to promptly respond to the antibiotic treatment in the colonized patient. The balance of the prevalence, E. aerogenes versus E. cloacae, in the reported hospital infections during the last period, questions about the horizontal transmission of mobile elements containing antibiotic resistance genes, e.g., the efficacy of the exchange of resistance genes Klebsiella pneumoniae to Enterobacter sp. It is also important to mention the possible role of antibiotic use in the treatment of bacterial infectious diseases in this E. aerogenes/E. cloacae evolution.
PubMed: 26042091
DOI: 10.3389/fmicb.2015.00392 -
Frontiers in Microbiology 2023, the gram-negative bacteria belonging to the family , lacks the ability to synthesize chemicals. However, in this study, a strain of NJ1023 screened from the soil...
, the gram-negative bacteria belonging to the family , lacks the ability to synthesize chemicals. However, in this study, a strain of NJ1023 screened from the soil containing petrochemicals was found to be capable of producing extracellular polysaccharides (EPSs). After purification of the polysaccharide, the chemical composition and physicochemical properties of the polysaccharide were analyzed by UV-Vis spectra, FTIR spectroscopy and GC-MS, etc. The results showed that: The molecular weight of the polysaccharide produced by this strain was only 2.7×10 Da, which was lower than that reported in other polysaccharides from the same genus. The polysaccharide produced by NJ1023 mainly comprised xylose, glucose, galactose, and N-acetylglucosamine with a molar ratio of 0.27: 4.52: 1.74: 0.2, which differed from those reported from the same genus. The results demonstrated that lower incubation temperatures and shaking speeds were more favorable for EPSs synthesis, while higher incubation temperatures and shaking speeds favored cell growth. Additionally, the EPSs produced by NJ1023 significantly protected the cells against cadaverine stress. Overall, the discovery of EPSs produced by increased the diversity of bacterial polysaccharides and broadened the potential applications of this species.
PubMed: 37577413
DOI: 10.3389/fmicb.2023.1200123 -
The Brazilian Journal of Infectious... 2015Enterobacter is a common nosocomial microorganism and its carbapenem's resistance has increased. The management of these cases is unclear.
BACKGROUND
Enterobacter is a common nosocomial microorganism and its carbapenem's resistance has increased. The management of these cases is unclear.
OBJECTIVE
We evaluated 16 patients with KPC-producing Enterobacter aerogenes infections, detailing the site of infection, therapy, clinical and epidemiological data.
METHODS
A retrospective and descriptive study. Clinical data were revised and KPC-2 detection was by molecular methods. Risk factors associated with mortality were compared using appropriate tests according to variable type with a significance level of 0.05.
RESULTS
The 30-day mortality rate was 37.5% with no association with inadequate treatment. Age (p=0.004) and Charlson score of comorbidities (p=0.048) were independent risk factors associated with death in the multivariate analysis. The odds ratio for age >43 years was 3.00 (95% CI: 1.02-9.32) and for Charlson score >3 was 2.00 (95% CI: 1.08-3.71). Five strains were pan-resistant based on automated susceptibility tests. All patients were treated with monotherapy.
CONCLUSION
The clinician should be alert to carbapenem-resistant Enterobacteriaceae infection in older patients with comorbidities. The mortality is high and we believe that prompt and adequate therapy must be employed.
Topics: Adult; Aged; Aged, 80 and over; Anti-Bacterial Agents; Enterobacter aerogenes; Enterobacteriaceae Infections; Female; Humans; Male; Microbial Sensitivity Tests; Middle Aged; Pregnancy; Retrospective Studies; Risk Factors; Young Adult; beta-Lactamases
PubMed: 25722130
DOI: 10.1016/j.bjid.2015.01.003 -
Journal of Global Antimicrobial... Jun 2021The genus Enterobacter is a common cause of nosocomial infections. Historically, the most frequent Enterobacter species were those of Enterobacter cloacae complex and...
OBJECTIVES
The genus Enterobacter is a common cause of nosocomial infections. Historically, the most frequent Enterobacter species were those of Enterobacter cloacae complex and Enterobacter aerogenes. In 2019, E. aerogenes was re-classified as Klebsiella aerogenes owing to its higher genotypic similarity with the genus Klebsiella. Our objective was to characterise and compare the clinical profiles of bacteraemia caused by E. cloacae and K. aerogenes.
METHODS
This 3-year multicentre, prospective cohort study enrolled consecutive patients with bacteraemia by E. cloacae or K. aerogenes. Baseline characteristics, bacteraemia features (source, severity, treatment), antibiotic susceptibility, resistance mechanisms and mortality were analysed.
RESULTS
The study included 285 patients with bacteraemia [196 (68.8%) E. cloacae and 89 (31.2%) K. aerogenes]. The groups showed no differences in age, sex, previous use of invasive devices, place of acquisition, sources or severity at onset. The Charlson score was higher among patients with E. cloacae bacteraemia [2 (1-4) vs. 1 (0.5-3); P = 0.018], and previous antibiotic therapy was more common in patients with K. aerogenes bacteraemia (57.3% vs. 41.3%; P = 0.01). Mortality was 19.4% for E. cloacae and 20.2% for K. aerogenes (P = 0.869). Antibiotic susceptibility was similar for both species, and the incidence of multidrug resistance or ESBL production was low (6% and 5.3%, respectively), with no differences between species.
CONCLUSION
Bacteraemias caused by E. cloacae and K. aerogenes share similar patient profiles, presentation and prognosis. Patients with E. cloacae bacteraemia had more co-morbidities and those with K. aerogenes bacteraemia had received more antibiotics.
Topics: Bacteremia; Enterobacter aerogenes; Enterobacter cloacae; Enterobacteriaceae Infections; Humans; Prospective Studies
PubMed: 33964492
DOI: 10.1016/j.jgar.2021.04.008 -
Microbiology Spectrum Feb 2023Enterobacter spp. and Klebsiella aerogenes are rod-shaped Gram-negative opportunistic pathogens. This study aimed at the molecular and genomic characterization of...
Enterobacter spp. and Klebsiella aerogenes are rod-shaped Gram-negative opportunistic pathogens. This study aimed at the molecular and genomic characterization of multidrug resistant Enterobacter spp. and K. aerogenes isolates recovered from hospitalized patients in a tertiary care hospital in Lebanon. A total of 59 Enterobacter spp. clinical isolates consisting of 41 carbapenem-resistant and 18 susceptible by Etest were included in this study. Genotypic identification through whole-genome sequencing (WGS) was performed and confirmed . Resistance and plasmid profiles were studied using ResFinder4.0 and Plasmid-Finder2.1. Multilocus sequence typing (MLST) was used to determine the isolates' clonality. Using the average nucleotide identity (ANI) we identified and confirmed that 47 (80%) isolates were . , 11 (18%) were Klebsiella aerogenes and 1 (2%) was an E. cloacae. Carbapenem-resistance was detected among 41 isolates all showing an MIC of ≥ 32 μg/mL for ertapenem, imipenem, and meropenem. (58.5%), (54%), and (54%) were the most common detected β-lactamases, while (68%) was the main detected extended-spectrum β-lactamase (ESBL) encoding gene. Chromosomal , carbapenemase encoding genes, and porin modifications were among the detected carbapenem resistance determinants. The carbapenemase encoding genes were linked to three well-defined plasmid Inc groups, IncFII/IncFIB, IncX3, and IncL. MLST typing revealed the diversity within the studied isolates, with ST114 being the most common among the studied . The spread of carbapenem-resistant isolates in clinical settings in Lebanon is a serious challenge. Screening and continuous monitoring through WGS analysis could effectively limit the dissemination of drug-resistant isolates in hospitalized patients. Drug resistance is an increasing global public health threat that involves most disease-causing organisms and antimicrobial drugs. Drug-resistant organisms spread in health care settings, and resistance to multiple drugs is common. Our study demonstrated the mechanisms leading to resistance against the last resort antimicrobial agents among members of the family. The spread of carbapenem-resistant bacteria in clinical settings is a serious challenge. Screening and continuous monitoring could effectively limit the dissemination of drug-resistant isolates in hospitalized patients.
Topics: Humans; Enterobacter aerogenes; Enterobacter; Anti-Bacterial Agents; Multilocus Sequence Typing; Lebanon; Bacterial Proteins; beta-Lactamases; Carbapenems; Microbial Sensitivity Tests; Klebsiella pneumoniae
PubMed: 36651778
DOI: 10.1128/spectrum.02917-22 -
Antibiotics (Basel, Switzerland) Apr 2023We retrospectively analyzed the antimicrobial data of spp. strains isolated from hospitalized subjects and outpatients over 20 years (2000-2019). A total of 2277...
We retrospectively analyzed the antimicrobial data of spp. strains isolated from hospitalized subjects and outpatients over 20 years (2000-2019). A total of 2277 non-duplicate spp. isolates, 1037 from outpatients (45%) and 1240 from hospitalized subjects (55%), were retrieved. Most of samples are infections of the urinary tract. Considering now classified as and , representing more than 90% of all isolates, except for aminoglycosides and fluroquinolones, which showed significant antibiotic decreasing trends ( < 0.01), none of the other antimicrobial agents tested showed significant changes in both groups ( > 0.05). Conversely, there was a significant increasing resistance trend for fosfomycin ( < 0.01), among both community and hospital-related subjects, most probably owing to uncontrolled and improper usage. Surveillance studies on antibiotic resistance at the local and regional level are required to detect new resistance mechanisms, reduce inappropriate antimicrobial consumption, and increase the focus on antimicrobial stewardship.
PubMed: 37107137
DOI: 10.3390/antibiotics12040775 -
Neurology India Mar 2024
Topics: Humans; Enterobacter aerogenes; Enterobacteriaceae Infections; Brain; Male
PubMed: 38691503
DOI: 10.4103/neurol-india.Neurol-India-D-24-00169 -
Journal of Infection in Developing... Jun 2016Bacterial resistance is a growing concern in the nosocomial environment in which Klebsiella pneumoniae and Enterobacter aerogenes play an important role due to their...
INTRODUCTION
Bacterial resistance is a growing concern in the nosocomial environment in which Klebsiella pneumoniae and Enterobacter aerogenes play an important role due to their opportunism and carbapenemase-production. This work aimed to evaluate physiological and molecular characteristics of carbapenem-resistant K. pneumoniae and E. aerogenes isolated in a Brazilian tertiary hospital.
METHODOLOGY
In total, 42 carbapenem-resistant bacteria isolated from clinical specimens were included (21 K. pneumoniae and 21 E. aerogenes). Drug-sensitive K. pneumoniae (n = 27) were also included. Antimicrobial susceptibility and biocide tolerance patterns, hemolytic activity, tolerance to oxidative stress, and aggregative ability were assessed. Genetic markers related to carbapenem resistance, or ESBL-production were screened by PCR.
RESULTS
Compared to drug-sensitive strains, carbapenem-resistant K. pneumoniae were more tolerant to biocides and to oxidative stress, and they displayed an increase in biofilm formation. The genetic markers blaKPC (95.2%) and blaTEM (90.5%) were the most frequent. Among the carbapenem-resistant E. aerogenes strains, blaKPC, and blaTEM were detected in all bacteria. Drug-sensitive E. aerogenes were not isolated in the same period. blaSHV, blaVIM, and blaCTX markers were also observed among carbapenem-resistant bacteria.
CONCLUSIONS
Results suggest that carbapenemase-producing enterobacteria might show peculiar characteristics regarding their physiology associated with their environmental persistency, virulence, and multidrug resistance. The observed phenomenon may have implications not only for antimicrobial chemotherapy, but also for the prognosis of infectious diseases and infection control.
Topics: Adult; Aged; Aged, 80 and over; Anti-Bacterial Agents; Biofilms; Brazil; Carbapenems; Cross-Sectional Studies; Disinfectants; Enterobacter aerogenes; Enterobacteriaceae Infections; Female; Humans; Klebsiella pneumoniae; Male; Middle Aged; Oxidative Stress; Polymerase Chain Reaction; Stress, Physiological; Tertiary Care Centers; Young Adult; beta-Lactam Resistance
PubMed: 27367007
DOI: 10.3855/jidc.6821