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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 -
Frontiers in Nutrition 2022Restrictive diets for the treatment of different gastrointestinal disorders are reported to change the composition of intestinal microbiota. Recently, it has been...
The dietary treatment of histamine intolerance reduces the abundance of some histamine-secreting bacteria of the gut microbiota in histamine intolerant women. A pilot study.
Restrictive diets for the treatment of different gastrointestinal disorders are reported to change the composition of intestinal microbiota. Recently, it has been proposed that individuals with histamine intolerance suffer from intestinal dysbiosis, having an overabundance of histamine-secreting bacteria, but how it is still unknown this state is affected by the usual dietary treatment of histamine intolerance [i.e., low-histamine diet and the supplementation with diamine oxidase (DAO) enzyme]. Thus, a preliminary study was carried out aiming to evaluate the potential changes on the composition of the intestinal microbiota in a group of five women diagnosed with histamine intolerance undergoing 9 months of the dietary treatment of histamine intolerance. After sequencing bacterial 16S rRNA genes (V3-V4 region) and analyzing the data using the EzBioCloud Database, we observed a reduction in certain histamine-secreting bacteria, including the genera and and the specie . Moreover, it was also observed an increase in spp., a bacterial group frequently related to gut health. These changes could help to explain the clinical improvement experienced by histamine intolerant women underwent a dietary treatment.
PubMed: 36337620
DOI: 10.3389/fnut.2022.1018463 -
Critical Reviews in Microbiology Mar 2019Polymyxins are important lipopeptide antibiotics that serve as the last-line defense against multidrug-resistant (MDR) Gram-negative bacterial infections. Worryingly,... (Review)
Review
Polymyxins are important lipopeptide antibiotics that serve as the last-line defense against multidrug-resistant (MDR) Gram-negative bacterial infections. Worryingly, the clinical utility of polymyxins is currently facing a serious threat with the global dissemination of , plasmid-mediated polymyxin resistance. The first plasmid-mediated polymyxin resistance gene, termed as was identified in China in November 2015. Following its discovery, isolates carrying , mainly and less commonly to , have been reported across Asia, Africa, Europe, North America, South America and Oceania. This review covers the epidemiological, microbiological and genomics aspects of this emerging threat to global human health. The has been identified in various species of Gram-negative bacteria including , , , , , , , , , , , and species from animal, meat, food product, environment and human sources. More alarmingly is the detection of in extended-spectrum-β-lactamases- and carbapenemases-producing bacteria. The can be carried by different plasmids, demonstrating the high diversity of plasmid reservoirs. Our review analyses the current knowledge on the emergence of -mediated polymyxin resistance.
Topics: Animals; Anti-Bacterial Agents; Bacterial Proteins; Drug Resistance, Bacterial; Gram-Negative Bacteria; Gram-Negative Bacterial Infections; Humans; Plasmids; Polymyxins; Transferases (Other Substituted Phosphate Groups)
PubMed: 31122100
DOI: 10.1080/1040841X.2018.1492902 -
Revista Medica Del Instituto Mexicano... Jan 2019The genus Raoultella, which belongs to the Enterobacteriaceae family, encompasses gramnegative, oxidase-negative, aerobic, encapsulated and motionless bacilli.... (Review)
Review
The genus Raoultella, which belongs to the Enterobacteriaceae family, encompasses gramnegative, oxidase-negative, aerobic, encapsulated and motionless bacilli. Currently, four species of this genus have been described: Raoultella terrigena (R. terrigena), Raoultella planticola (R. planticola), Raoultella ornithinolytica (R. ornithinolytica) and Raoultella electrica (R. electrica), out of which R. planticola and R. ornithinolytica are the most important because of their probable association as pathogenic agents. The incidence of this genus has been underestimated, given that detecting it is really difficult, since it is misidentified as Klebsiella spp. by using manual and automated conventional phenotypic methods. The rapid and correct detection has been increasing since the advent of mass spectrometers (MALDI-TOF MS), which have been used for the differentiation of Klebsiella spp. and Raoultella spp. Currently 80 cases of bacteremia secondary to Raoultella spp. have been identified with different sites of primary infection, which is why it is important to emphasize proper detection in hospitals and healthcare facilities.
Topics: Bacteremia; Bacterial Typing Techniques; Diagnosis, Differential; Diagnostic Errors; Enterobacteriaceae; Enterobacteriaceae Infections; Humans
PubMed: 30777417
DOI: No ID Found -
Diagnostic Microbiology and Infectious... Jun 2023A total of 35,360 Enterobacterales isolates were consecutively collected from 75 US medical centers in 2018-2022. Among these isolates, 2612 (7.4%) were categorized as...
Ceftazidime-avibactam, meropenem-vaborbactam, and imipenem-relebactam activities against multidrug-resistant Enterobacterales from United States Medical Centers (2018-2022).
A total of 35,360 Enterobacterales isolates were consecutively collected from 75 US medical centers in 2018-2022. Among these isolates, 2612 (7.4%) were categorized as multidrug-resistant (MDR). Isolates were susceptibility tested by reference broth microdilution methods. Carbapenem-resistant Enterobacterales (CRE) were screened for carbapenemase (CPE) genes by whole genome sequencing. The highest MDR rates was observed among Klebsiella pneumoniae (12.2%), followed by Raoultella spp. (10.9%) and Providencia stuartii (9.8%). Ceftazidime-avibactam and meropenem-vaborbactam were very active and showed identical susceptibility rates against MDR isolates (97.9%). Imipenem-relebactam (93.5% susceptible [S]) exhibited slightly lower susceptibility rates due to its limited activity against Morganellaceae family. The most active β-lactamase inhibitor combination (BLI) against CRE isolates (n = 310) was ceftazidime-avibactam (84.2%S), followed by meropenem-vaborbactam (81.9%S) and imipenem-relebactam (74.8%S). All 3 BLIs were very active against KPC producers and none were active against MBL producers. Ceftazidime-avibactam exhibited greater activity against OXA-48-type producers than meropenem-vaborbactam and imipenem-vaborbactam.
Topics: United States; Humans; Meropenem; Anti-Bacterial Agents; Ceftazidime; Azabicyclo Compounds; Drug Combinations; Imipenem; beta-Lactamases; Carbapenems; Microbial Sensitivity Tests
PubMed: 37060707
DOI: 10.1016/j.diagmicrobio.2023.115945 -
Frontiers in Cellular and Infection... 2024spp. is a genus of bacteria that is known to be closely related to . It has been debated whether should be reclassified as a subgroup of . The aim of this study is to... (Comparative Study)
Comparative Study
PURPOSE
spp. is a genus of bacteria that is known to be closely related to . It has been debated whether should be reclassified as a subgroup of . The aim of this study is to compare clinical aspects of and , a species of that is known to be bacteriologically similar to spp.
METHODS
Using data collected at a tertiary care hospital in the United States, we identified 43 patients with infection and 1173 patients with infection. We compared patient demographics (age and sex), hospitalization status, isolation sites and antibiotic resistance profiles between the two species.
RESULTS
There was no significant difference in patient demographics between the two bacteria species. The proportions of intensive care unit (ICU) admission were higher among patients with infection (p=0.008). The most common site of isolation was urine for both species (39.5% of all patients with spp. vs. 59.3% for ). The second most common site of isolation was blood stream for spp. (23.3%) and respiratory tract for (10.8%). Except for the high proportion of resistant isolates of spp. for Trimethoprim/sulfamethoxazole, the antibiotic susceptibility profiles were similar between the two bacteria species. Both were susceptible to ciprofloxacin and meropenem.
CONCLUSION
While there are no significant differences in the patient demographics and antibiotic susceptibility profiles between spp. and , may cause more serious infection requiring ICU admissions. Also, may cause blood stream infection more frequently than .
Topics: Humans; Male; Klebsiella oxytoca; Female; Middle Aged; Aged; Enterobacteriaceae; Klebsiella Infections; Anti-Bacterial Agents; Enterobacteriaceae Infections; Microbial Sensitivity Tests; Adult; Tertiary Care Centers; Intensive Care Units; United States; Aged, 80 and over; Drug Resistance, Bacterial
PubMed: 38887491
DOI: 10.3389/fcimb.2024.1260212 -
PloS One 2023To study antimicrobial resistance and virulence genes of Klebsiella pneumoniae and Raoultella strains isolated from captive giant pandas. Non-duplicate fecal samples...
To study antimicrobial resistance and virulence genes of Klebsiella pneumoniae and Raoultella strains isolated from captive giant pandas. Non-duplicate fecal samples were collected from 128 giant pandas during 2017-2019. All isolated microbial strains were tested for antimicrobial drug susceptibility using BD verification panels. Four extended-spectrum β-lactamase resistance genes, nine virulence genes and six capsular serotype genes were detected using PCR. 42 K. pneumoniae and nine Raoultella strains were isolated from different giant pandas. Antibiotic resistance rates were 1.9%-23.5%, except for ampicillin, and 7.8% of the isolates were multidrug-resistant to 7-10 antibiotic classes. This is the first time that a multidrug-resistant R. ornithinolytica strain has been isolated from captive giant pandas. The blaTEM, blaCTX-M, blaSHV and blaDHA genes were detected in four MDR ESBL- K. pneumoniae strains. The rmpA, iutA, ybtS, iroN and iroB genes were positively detected in 11.7% of the isolates. Capsular serotype (K2, K5, K54 and K57) genes were all detected in four K. pneumoniae strains, and one was identified as hypervirulent. This study showed that MDR ESBL- K. pneumoniae, hypervirulent K. pneumoniae, MDR R. ornithinolytica and the colistin-resistant strain may pose risks to captive giant pandas and their keepers, and that the diversity of antibiotic resistance and virulence genes in Klebsiella and Raoultella should be monitored regularly.
Topics: Animals; Anti-Bacterial Agents; Virulence; Klebsiella pneumoniae; Ursidae; Drug Resistance, Bacterial; Prevalence; Klebsiella Infections; beta-Lactamases; Microbial Sensitivity Tests
PubMed: 36996135
DOI: 10.1371/journal.pone.0283738 -
Cureus Sep 2021is a gram-negative, aerobic, nonmotile bacteria that can be found in soil and water. This is a relatively rare organism with few case reports on it and only three...
is a gram-negative, aerobic, nonmotile bacteria that can be found in soil and water. This is a relatively rare organism with few case reports on it and only three reports of -induced urinary tract infection (UTI) have been reported. Here we present a case of acute cystitis caused by in a woman with atrial fibrillation and recurrent UTIs.
PubMed: 34660160
DOI: 10.7759/cureus.17985 -
Liver Transplantation : Official... May 2021The gut microbiome is altered in cirrhosis. Recent evidence has suggested a key role for the gut microbiota in the progression of cirrhosis and the development of...
The gut microbiome is altered in cirrhosis. Recent evidence has suggested a key role for the gut microbiota in the progression of cirrhosis and the development of hepatocellular carcinoma (HCC). We studied the differences in the microbial composition in patients with cirrhosis with prior and future HCC in the context of other complications (eg, infections, hepatic encephalopathy). The following 2 cohorts were recruited prospectively: the prior HCC cohort, in which outpatients with HCC within 2 years were age-matched, sex-matched, and Model for End-Stage Liver Disease (MELD) score-matched with those without HCC; and the future HCC cohort, in which patients were followed for 2 years and divided into future HCC versus no HCC after age, sex, and MELD-score matching and other complications were also recorded. Microbiota composition and predicted function were analyzed with ribosomal RNA sequencing and Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PiCRUST)and compared between (1) prior HCC versus none and (2) future HCC versus none, and in the future cohort, comparisons were also made between those patients who developed (1) HCC only versus without complications, (2) HCC only versus non-HCC complications only, and (3) HCC + other complications versus non-HCC complications only. A total of 142 men (76 total in the prior cohort [38 with/38 without HCC] and 66 total in the future cohort [33 with/33 without future HCC]) were included. The groups had similar etiology, lactulose/rifaximin/proton pump inhibitor use, diabetes mellitus, and non-HCC complications. Microbial diversity was similar between prior HCC/not or future HCC/not. On DESeq2 higher Clostridium sensu stricto and Anaerotruncus were significantly associated with protection from HCC, whereas the reverse was seen with Raoultella and Haemophilus regardless of prior/future HCC comparisons. Functions focused on urea cycle, bioenergetics, tryptophan, and toluene metabolism were different between the groups. Rothia was specific for other complications. Despite age, sex, and MELD-score matching and accounting for other complications, gut microbiota composition and the predicted function are different in men with cirrhosis with and without prior HCC and can be extended toward future HCC development.
Topics: Carcinoma, Hepatocellular; Child, Preschool; End Stage Liver Disease; Gastrointestinal Microbiome; Humans; Liver Cirrhosis; Liver Neoplasms; Liver Transplantation; Male; Phylogeny; Severity of Illness Index
PubMed: 33492761
DOI: 10.1002/lt.25994 -
Scientific Reports Mar 2022Raoultella planticola is an emerging pathogen causing several infections in humans, and its roles in the propagation of antibiotic resistance genes (ARGs) remain...
Raoultella planticola is an emerging pathogen causing several infections in humans, and its roles in the propagation of antibiotic resistance genes (ARGs) remain uncharacterized. In this study, a carbapenem and tigecycline-resistant R. planticola isolate was recovered from hospital sewage. It carried nine plasmids, bearing 30 ARGs, including one bla and two bla. It also contained a plasmid-borne efflux pump gene cluster, tmexCD1-toprJ, conferring resistance to tigecycline. Analysis of plasmid sequences revealed that both bla-carrying plasmids were highly similar to those recovered from humans, reinforcing the close relatedness of environmental and clinical isolates. We also identified that plasmid bearing bla or tmexCD1-toprJ1 was transferable, and can be stabilized in the host bacteria, indicating that the R. planticola isolate has a considerable potential in the dissemination of ARGs. Besides, we found that this isolate could produce biofilm and was virulent in a Galleria mellonella infection model. In conclusion, our study shows the convergence of virulence and multidrug resistance in a R. planticola isolate. This potentially virulent superbug may disseminate into its receiving rivers, and finally to humans through cross-contamination during recreation activities or daily use of water, which poses a risk to public health.
Topics: Anti-Bacterial Agents; Carbapenems; Enterobacteriaceae; Humans; Klebsiella pneumoniae; Microbial Sensitivity Tests; Plasmids; Tigecycline; Virulence; beta-Lactamases
PubMed: 35264602
DOI: 10.1038/s41598-022-07778-0