-
Diseases (Basel, Switzerland) Sep 2023Infective endocarditis remains a condition associated with high morbidity and mortality, regardless of advances in diagnosis and therapeutics. The etiology,...
Infective endocarditis remains a condition associated with high morbidity and mortality, regardless of advances in diagnosis and therapeutics. The etiology, microbiology, and epidemiology of infective endocarditis have changed in the last years, with healthcare-associated infective endocarditis being responsible for a myriad of cases. is rarely the cause of infective endocarditis. We present a 72-year-old Caucasian female with a history of mitral valve replacement for rheumatic valve disease two months before the current presentation, without any immunosuppressive pathologies, diagnosed with infective endocarditis. Long-drawn antibiotic treatment led to a full recovery with no evidence of recurrence or relapse. This report highlights the importance of a multimodal approach for the diagnosis of bacterial etiology, the importance of selection and duration of an appropriate antibiotic regimen, and the presence of a rare opportunistic bacteria that has proven pathogenicity in a wide range of organ systems, usually in patients with several risk factors.
PubMed: 37873777
DOI: 10.3390/diseases11040133 -
Microbiology and Immunology Jan 2024Over the last decade, New Delhi metallo-beta-lactamase (NDM) carbapenemase has silently spread in Brazil. In this study, we analyzed a large collection of...
Genomic characterization of New Delhi metallo-beta-lactamase-producing species of Morganellaceae, Yersiniaceae, and Enterobacteriaceae (other than Klebsiella) from Brazil over 2013-2022.
Over the last decade, New Delhi metallo-beta-lactamase (NDM) carbapenemase has silently spread in Brazil. In this study, we analyzed a large collection of Enterobacterales other than Klebsiella spp. received in our reference laboratory between 2013 and 2022. A total of 32 clinical isolates displaying different pulsed-field gel electrophoresis profiles, and represented by 11 species in the families Enterobacteriaceae (Citrobacter freundii, Citrobacter portucalensis, Enterobacter hormaechei, and Escherichia coli), Morganellaceae (Morganella morganii, Proteus mirabilis, Proteus vulgaris, Providencia rettgeri, Providencia stuartii, and Raoultella ornithinolytica), and Yersiniaceae (Serratia marcescens) had their whole genomes sequenced and further analyzed. Antimicrobial susceptibility was determined by disk diffusion, except for polymyxin B, assessed by broth microdilution. The bla allele was predominant (n = 29), but bla was identified in an E. coli specimen with a novel ST, and the bla allele was found in E. hormaechei ST45 and E. coli ST1049. Polymyxin was active against all but one Enterobacteriaceae isolate: an mcr-1-producing E. coli presenting minimal inhibitory concentration (4 mg/L). Isolates producing extended-spectrum β-lactamases were common: cefotaximase from Munich (CTX-M)-15 (n = 10), CTX-M-2 (n = 4), and CTX-M-8 (n = 3) were detected, and the mcr-1-producing E. coli was found to co-produce both CTX-M-8 and CTX-M-55 β-lactamases. The mcr-9 gene was found in 5/8 E. hormaechei isolates, distributed in four different sequence types, all of them presenting susceptibility to polymyxin. This study showed that NDM-producing Enterobacterales other than Klebsiella are already spread in Brazil, in diversified species, and cocarrying important resistance genes. Prompt detection and effective implementation of measures to prevent further spread are mandatory for mitigating the dissemination of NDM carbapenemase in hospital settings and preserving the already limited antimicrobial therapy options.
Topics: Humans; Escherichia coli; Klebsiella; Brazil; Anti-Bacterial Agents; beta-Lactamases; Enterobacteriaceae Infections; Genomics; Microbial Sensitivity Tests; Polymyxins
PubMed: 37859304
DOI: 10.1111/1348-0421.13100 -
Journal of Infection in Developing... Sep 2023The spread of multidrug-resistant bacteria, particularly carbapenem-resistant Gram-negative bacilli (CR-GNB), has become a serious challenge for clinicians due to...
INTRODUCTION
The spread of multidrug-resistant bacteria, particularly carbapenem-resistant Gram-negative bacilli (CR-GNB), has become a serious challenge for clinicians due to limited therapeutic options. The aim of the study was to investigate the prevalence of carbapenemase production among clinical isolates recovered from 352 samples collected in Tebessa hospital, Algeria.
METHODOLOGY
Bacterial isolates were identified by 16S RNA gene sequencing and susceptibility to antibiotics was determined by disk diffusion method. Carbapenem-resistant isolates were screened for carbapenemase production using modified carba Nordmann-Poirel test, modified Hodge test and imipenem-EDTA combined disc test. Extended-spectrum β-lactamases (ESBL) were detected using double-disk synergy test. Molecular characterization of carbapenemases and ESBL genes was performed by polymerase chain reaction (PCR) and sequencing.
RESULTS
A total of 85 Gram-negative bacilli isolates were recovered mainly from urine samples and were identified as: Klebsiella pneumoniae (17.65%), Serratia odorifera (15.29%), Escherichia coli (12.94%), Raoultella ornithinolytica, Enterobacter cloacae (11.76%), Serratia marcescens (10.59%), Morganella morganii (7.06%), Proteus mirabilis (5.88%), Acinetobacter baumannii (4.70%) and Pseudomonas aeruginosa (2.35%). All strains were resistant or intermediate to imipenem and/or ertapenem. ESBL, carbapenemase and metallo-beta-lactamases (MBL) phenotypes were detected in 19 (22.35%), 9 (10.59%) and 2 (2.35%) GNB isolates, respectively. PCR results in nine carbapenemase-producing GNB strains chosen showed the presence of one to four carbapenemase genes (blaGES, blaSME, blaNDM-1, blaVIM, blaGIM, blaSPM, blaOXA-48) in four strains; however, seven strains had at least one ESBL gene (blaTEM-1, blaCTXM-15, blaSHV).
CONCLUSIONS
In this study, we report the first incidence of blaNDM-1 gene in Enterobacter cloacae isolated from urine sample in Algeria.
Topics: Enterobacter cloacae; beta-Lactamases; Bacterial Proteins; Gram-Negative Bacteria; Anti-Bacterial Agents; Carbapenems; Imipenem; Escherichia coli; Microbial Sensitivity Tests
PubMed: 37824354
DOI: 10.3855/jidc.18031 -
Applied and Environmental Microbiology Oct 2023While the evolution of antimicrobial resistance is well studied in free-living bacteria, information on resistance development in dense and diverse biofilm communities...
While the evolution of antimicrobial resistance is well studied in free-living bacteria, information on resistance development in dense and diverse biofilm communities is largely lacking. Therefore, we explored how the social interactions in a duo-species biofilm composed of the brewery isolates and influence the adaptation to the broad-spectrum antimicrobial sulfathiazole. Previously, we showed that the competition between these brewery isolates enhances the antimicrobial tolerance of . Here, we found that this enhanced tolerance in duo-species biofilms is associated with a strongly increased antimicrobial resistance development in . Whereas was not able to evolve resistance against sulfathiazole in monospecies conditions, it rapidly evolved resistance in the majority of the duo-species communities. Although the initial presence of was thus required for to acquire resistance, the resistance mechanisms did not depend on the presence of . Whole genome sequencing of resistant clones showed no clear mutational hot spots. This indicates that the acquired resistance phenotype depends on complex interactions between low-frequency mutations in the genetic background of the strains. We hypothesize that the increased tolerance in duo-species conditions promotes resistance by enhancing the selection of partially resistant mutants and opening up novel evolutionary trajectories that enable such genetic interactions. This hypothesis is reinforced by experimentally excluding potential effects of increased initial population size, enhanced mutation rate, and horizontal gene transfer. Altogether, our observations suggest that the community mode of life and the social interactions therein strongly affect the accessible evolutionary pathways toward antimicrobial resistance.IMPORTANCEAntimicrobial resistance is one of the most studied bacterial properties due to its enormous clinical and industrial relevance; however, most research focuses on resistance development of a single species in isolation. In the present study, we showed that resistance evolution of brewery isolates can differ greatly between single- and mixed-species conditions. Specifically, we observed that the development of antimicrobial resistance in certain species can be significantly enhanced in co-culture as compared to the single-species conditions. Overall, the current study emphasizes the need of considering the within bacterial interactions in microbial communities when evaluating antimicrobial treatments and resistance evolution.
Topics: Anti-Infective Agents; Biofilms; Bacteria; Phenotype; Sulfathiazoles; Anti-Bacterial Agents
PubMed: 37819078
DOI: 10.1128/aem.01155-23 -
in a Healthy, Young Person: Rapidly Progressive Sinusitis with Orbital and Intracranial Involvement.European Journal of Case Reports in... 2023is an encapsulated, Gram-negative, nonmotile, rod belonging to the family. Infections involving the gastrointestinal tract and the hepatopancreatobiliary system are...
UNLABELLED
is an encapsulated, Gram-negative, nonmotile, rod belonging to the family. Infections involving the gastrointestinal tract and the hepatopancreatobiliary system are most frequently reported, especially in immunocompromised patients. The authors present an unusual case of acute complicated sinusitis with orbital and intracranial involvement caused by . The infection was rapidly progressive, even though the patient was a healthy, young person without any co-morbidities. The patient's condition improved after antibiotic treatment and multiple ophthalmic and sinus surgeries.
LEARNING POINTS
can cause rapidly progressive infections, even in immunocompetent young individuals. identified in sinusitis can be a true pathogen rather than an innocent bystander.
PubMed: 37789980
DOI: 10.12890/2023_003987 -
Journal of Environmental Management Dec 2023Microorganisms obtain inorganic nutrients or energy from specific minerals to selectively weather minerals, but few studies on the differences in metabolic components of...
Microorganisms obtain inorganic nutrients or energy from specific minerals to selectively weather minerals, but few studies on the differences in metabolic components of different functional bacteria lead to different weathering effects. This study evaluated the leaching effects of two bacteria with distinct metabolic characteristics on lithium silicate minerals with different structures. We aimed to understand the microscopic mechanism of crystal destruction of lithium silicate minerals with different structures under the action of microorganisms. The results showed that the metabolites produced by an acid producing silicate strain Raoultella sp. Z107 (strain Z107) had a high content of organic acids, among which lactic acid was up to about 11 g/L. Bacillus mucilaginosus 21,699 (strain BM) secreted capsular polysaccharide with a high content of 14.84 mg/L. The metabolic activities of the two strains were significantly different. Through the analysis of the leaching residue, it was found that the lithium silicate minerals were acid etched, interlayer domains expanded, crystallinity decreased, and metal bonds were broken under the action of bacteria. The dissolution of lithium silicate minerals by bacteria is a combination of bacterial adsorption, organic acid corrosion, and complexation of small molecular organic acids and macromolecular polymers with metal ions. The acid erosion and complexation effects of organic acids are greater than the single complexation of capsular polysaccharides, and the layered lepidolite is more likely to be decomposed by the weathering of bacterial metabolites than the chain structure spodumene. These results indicate that the diversity of metabolic activity of bacteria from different sources and the sequence and decomposition mechanism of metal ions released from minerals after lattice destruction are also different. Microorganisms decompose minerals for energy and nutrients, and eventually become the main players in the transformation of elements in biogeology.
Topics: Lithium; Silicates; Minerals; Ions; Organic Chemicals
PubMed: 37783078
DOI: 10.1016/j.jenvman.2023.119082 -
International Journal of Food... Dec 2023Bacterial biofilm is a major concern of dairy industry due to its association with milk contamination and its derived products. Algerian pasteurized milk shelf-life does...
Bacterial biofilm is a major concern of dairy industry due to its association with milk contamination and its derived products. Algerian pasteurized milk shelf-life does not exceed one day, which may reflect the high level of contamination of this product and presence of extracellular enzymes such as lipases and proteases. This work aimed to investigate the microbial biodiversity in milk-processing surfaces of a dairy plant in Algeria. Therefore, stainless steel cylinders were placed in piping system of the dairy system before and after pasteurization of the milk, being removed after 7 days, for biofilm maturation and microorganism isolation and identification by mass spectrometry. Fifty-nine Gram-positive isolates were identified, namely Bacillus altitudinis, Bacillus cereus, Bacillus pumilus, Bacillus subtilis, Bacillus weithenstephanensis, Enterococcus casseliflavus, Enterococcus faecium, and Staphylococcus epidermidis. In addition, twenty-four Gram-negative isolates were identified, namely Acinetobacter schindleri Enterobacter cloacae, Enterobacter xiangfangensis, Leclercia adecarboxylata, and Raoultella ornithinolytica. Bacterial isolates showed ability for production of extracellular enzymes, being 49 % capable of both proteolytic and lipolytic activities. Milk isolates were tested for the ability to form biofilms on stainless steel. The cell numbers recovered on plate count agar plates from stainless steel biofilms ranged from 3.52 to 6.92 log10 CFU/cm, being the maximum number detected for Enterococcus casseliflavus. Bacterial isolates showed intermediate and/or resistant profiles to multiple antibiotics. Resistance to amoxicillin, cefoxitin and/or erythromycin was commonly found among the bacterial isolates.
Topics: Animals; Pasteurization; Milk; Stainless Steel; Algeria; Biofilms; Bacillus subtilis
PubMed: 37708608
DOI: 10.1016/j.ijfoodmicro.2023.110389 -
Frontiers in Microbiology 2023The purpose of this study was to highlight the clinical and molecular features of 13 strains isolated from clinical environments in Ecuador, and to perform comparative...
PURPOSE
The purpose of this study was to highlight the clinical and molecular features of 13 strains isolated from clinical environments in Ecuador, and to perform comparative genomics with previously published genomes of spp. As is primarily found in environmental, clinical settings, we focused our work on identifying mechanisms of resistance that can provide this bacterium an advantage to establish and persist in hospital environments.
METHODS
We analyzed 13 strains of isolated from patients with healthcare associated infections (HAI) in three hospitals in Quito and one in Santo Domingo de Los Tsáchilas, Ecuador, between November 2017 and April 2018. These isolates were subjected to phenotypic antimicrobial susceptibility testing, end-point polymerase chain reaction (PCR) to detect the presence of carbapenemases and whole-genome sequencing.
RESULTS
Polymerase chain reaction revealed that seven isolates were positive isolates for and one for gene. Of the seven strains that presented the gene, six harbored it on an IncFII plasmid, one was inserted into the bacterial chromosome. The gene was detected in an IncM2/IncR plasmid. From the bioinformatics analysis, nine genomes had the gene , originating from Ecuador. Moreover, all strains contained the ORN-1 gene, which confers resistance for β-lactams, such as penicillins and cephalosporins. Comparative genome analysis of the strains showed that the pangenome of is considered an open pangenome, with 27.77% of core genes, which could be explained by the fact that the antibiotic resistance genes in the ancestral reconstruction are relatively new, suggesting that this genome is constantly incorporating new genes.
CONCLUSION
These results reveal the genome plasticity of , particularly in acquiring antibiotic-resistance genes. The genomic surveillance and infectious control of these uncommon species are important since they may contribute to the burden of antimicrobial resistance and human health.
PubMed: 37692398
DOI: 10.3389/fmicb.2023.1216008 -
Data in Brief Oct 2023PX02 is a Gram-negative, encapsulated bacterium, part of the family, emerging as a notable human pathogen. Here, we present the whole genome sequence of PX02...
PX02 is a Gram-negative, encapsulated bacterium, part of the family, emerging as a notable human pathogen. Here, we present the whole genome sequence of PX02 isolated from San Jacinto River sediment near a Burnet Shores community in Baytown, Texas. This microorganism harbors a large 200,000 bp incF plasmid and can potentially be a significant antibiotic reservoir. The PX02 genome consists of 5,970,914 base pairs encoding approximately 5,661 functional proteins. Strain PX02 (chromosomal and plasmid) was compiled at the scaffold level and can be accessed through the National Center for Biotechnology Information database under accession NZ_NJBC00000000.1.
PubMed: 37674506
DOI: 10.1016/j.dib.2023.109506 -
Molecules (Basel, Switzerland) Aug 2023Biological methods are currently the most commonly used methods for removing hazardous substances from land. This research work focuses on the remediation of...
Biological methods are currently the most commonly used methods for removing hazardous substances from land. This research work focuses on the remediation of oil-contaminated land. The biodegradation of aliphatic hydrocarbons and PAHs as a result of inoculation with biopreparations B1 and B2 was investigated. Biopreparation B1 was developed on the basis of autochthonous bacteria, consisting of strains sp. IN118, sp. IN101, IN53, IN119, IN113 and sp. IN109, whereas biopreparation B2 was enriched with fungi, such as , , sp., , . As a result of biodegradation tests conducted under ex situ conditions for soil inoculated with biopreparation B1, the concentrations of TPH and PAH were reduced by 31.85% and 27.41%, respectively. Soil inoculation with biopreparation B2 turned out to be more effective, as a result of which the concentration of TPH was reduced by 41.67% and PAH by 34.73%. Another issue was the phytoremediation of the pre-treated G6-3B2 soil with the use of . The tests were carried out in three systems (system 1-soil G6-3B2 + ; system 2-soil G6-3B2 + biopreparation B2 + ; system 3-soil G6-3B2 + biopreparation B2 with γ-PGA + ) for 6 months. The highest degree of TPH and PAH reduction was obtained in system 3, amounting to 65.35% and 60.80%, respectively. The lowest phytoremediation efficiency was recorded in the non-inoculated system 1, where the concentration of TPH was reduced by 22.80% and PAH by 18.48%. Toxicological tests carried out using Phytotoxkit, Ostracodtoxkit and Microtox Solid Phase tests confirmed the effectiveness of remediation procedures and showed a correlation between the concentration of petroleum hydrocarbons in the soil and its toxicity. The results obtained during the research indicate the great potential of bioremediation practices with the use of microbial biopreparations and in the treatment of soils contaminated with petroleum hydrocarbons.
Topics: Zea mays; Biodegradation, Environmental; Hazardous Substances; Actinomycetales; Enterobacteriaceae
PubMed: 37630356
DOI: 10.3390/molecules28166104