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Bulletin of Experimental Biology and... Dec 2023We studied the influence of medium composition and aeration on the hemolytic activity of uropathogenic Morganella morganii strain MM 190. The maximum level of hemolysis...
We studied the influence of medium composition and aeration on the hemolytic activity of uropathogenic Morganella morganii strain MM 190. The maximum level of hemolysis was observed in LB (59%), DMEM supplemented with fetal bovine serum (62%), and urine (53%) under aeration conditions during the exponential growth phase. The presence of 2% urea in the medium suppressed hemolysin synthesis. Moreover, addition of bacterial culture fluid containing hemolysin to a monolayer of T-24 bladder carcinoma and OKP-GS kidney carcinoma cells led to 25 and 42% cell death, respectively. We found that the maximum expression of the hemolysin gene hlyA was observed in 2-h culture in LB medium, which correlated with the hemolytic activity of the bacteria in this medium and indicated the predominance of the short hlyCA transcript in the cells.
Topics: Humans; Morganella morganii; Hemolysin Proteins; Antigens, Bacterial; Hemolysis; Carcinoma
PubMed: 38191876
DOI: 10.1007/s10517-024-05991-7 -
Journal of Infection and Public Health Mar 2024Morganella morganii is a Gram-negative, opportunistic pathogen that can cause a variety of infections, including bloodstream infections, especially in those with...
BACKGROUND
Morganella morganii is a Gram-negative, opportunistic pathogen that can cause a variety of infections, including bloodstream infections, especially in those with compromised immune systems. It is often resistant to antibiotics, making it a difficult organism to treat. Limited studies have addressed M. morganii, but the organism is becoming increasingly recognized as a public health threat. More research is needed to understand the epidemiology and virulence factors of M. morganii in Saudi Arabia, as well as to develop effective treatment strategies.
METHODS
This retrospective study included all M. morganii bloodstream infections patients admitted to five tertiary care hospitals in Saudi Arabia between 2015 and 2022.
RESULTS
The study population included 75 patients (45 males and 30 females) between the age of 53-72 with a 54% ICU admission rate. The most comorbidities were hypertension followed by diabetes. The most common symptoms were fever, cough, shortness of breath, vomiting, and fatigue. The study also found that M. morganii was often resistant to multiple antibiotics, including ciprofloxacin, trimethoprim/sulfamethoxazole, gentamicin, amoxicillin, nitrofurantoin, and colistin. The most common treatment for M. morganii bacteremia was carbapenems, followed by aminoglycosides, ciprofloxacin, and colistin. Source control measures, such as surgery, line removal, drainage, and tissue removal, were also used in some cases. The study found that the in-hospital mortality rate for M. morganii bacteremia was 41%. The risk of mortality was increased in patients who were admitted to the ICU, who were older than 65 years, and who had Klebsiella pneumoniae co-infection.
CONCLUSION
M. morganii bacteremia is a serious infection that is often resistant to antibiotics. Elderly patients and patients with comorbidities are at increased risk of mortality. Source control measures and appropriate antibiotic therapy are important for improving outcomes.
Topics: Male; Female; Humans; Aged; Morganella morganii; Retrospective Studies; Enterobacteriaceae Infections; Colistin; Microbial Sensitivity Tests; Anti-Bacterial Agents; Bacteremia; Sepsis; Ciprofloxacin
PubMed: 38262080
DOI: 10.1016/j.jiph.2023.12.013 -
Foods (Basel, Switzerland) Sep 2023, a spoilage bacterium in fermented foods, produces harmful biogenic amines (BAs). Although is widely used to inhibit spoilage bacteria, the inhibition pattern and...
, a spoilage bacterium in fermented foods, produces harmful biogenic amines (BAs). Although is widely used to inhibit spoilage bacteria, the inhibition pattern and inhibition mechanism of by are not well studied. In this study, we analysed the effects of the addition of cell-free supernatant (CFS) on the growth and BA accumulation of and revealed the mechanisms of changes in different BAs by using RNA sequencing transcriptome analysis. The results showed that CFS could significantly inhibit BAs in a weak acid environment (pH 6), and the main changes were related to metabolism. Carbohydrate and energy metabolism were significantly down-regulated, indicating that CFS inhibited the growth activity and decreased the BA content of . In addition, the change in histamine content is also related to the metabolism of its precursor amino acids, the change in putrescine content may also be related to the decrease in precursor amino acid synthesis and amino acid transporter, and the decrease in cadaverine content may also be related to the decrease in the cadaverine transporter. The results of this study help to inhibit the accumulation of harmful metabolites in fermented foods.
PubMed: 37835277
DOI: 10.3390/foods12193625 -
Antibiotics (Basel, Switzerland) Aug 2023Bioindicator species are used to assess the damage and magnitude of possible impacts of anthropic origin on the environment, such as the reckless consumption of...
Bioindicator species are used to assess the damage and magnitude of possible impacts of anthropic origin on the environment, such as the reckless consumption of antimicrobials. has several characteristics that make it a suitable bioindicator of marine pollution and of the presence of pathogens that cause diseases in humans. This study aimed to investigate the green sea turtle as a reservoir of resistant bacteria, mainly because is the most frequent sea turtle species in Brazilian coastal regions and, consequently, under the intense impact of anthropic factors. Free-living green sea turtles ranging from 42.8 to 92 cm (average = 60.7 cm) were captured from Itaipú Beach, Brazil. Cloaca samples (characterizing the gastrointestinal tract) and neck samples (representing the transient microbiota) were collected. Bacterial species were identified, and their was resistance associated with the antimicrobials cephalothin, ciprofloxacin, gentamicin, tetracycline, and vancomycin. , , and were found resistant to cephalothin and and tetracycline-resistant isolates in cloaca samples. In neck samples, species resistant to tetracycline were sp., , and . This data reinforces that the green turtle is a bioindicator of antimicrobial resistance (AMR).
PubMed: 37627688
DOI: 10.3390/antibiotics12081268 -
BMC Ophthalmology Nov 2023Endophthalmitis following intravitreal injection is a potentially devastating complication of anti-VEGF injections. Post-injection endophthalmitis due to Enterococcus...
BACKGROUND
Endophthalmitis following intravitreal injection is a potentially devastating complication of anti-VEGF injections. Post-injection endophthalmitis due to Enterococcus faecalis is rare, and no previous case of Morganella morganii endophthalmitis after intravitreal injection has been reported.
CASE PRESENTATION
We present the first reported case of Morganella morganii and Enterococcus faecalis endophthalmitis after intravitreal injection in an immunocompetent patient in the absence of recent ocular surgery. Our patient presented with hand movement visual acuity one day after anti-VEGF injection and demonstrated no clinical improvement despite repeated intravitreal ceftazidime and vancomycin injections. A decision was made to proceed with early vitrectomy given failure of intravitreal antibiotics. Visual acuity improved to 6/90 at 12 weeks after vitrectomy without any evidence of disease recurrence.
CONCLUSIONS
Post-injection endophthalmitis due to concurrent Morganella morganii and Enterococcus faecalis infections can have visually devastating consequences despite repeated empirical and targeted intravitreal antibiotics. Lack of clinical improvement following intravitreal antibiotics should warrant consideration of early vitrectomy. Our experience is a pertinent reminder of the ever-growing threat of uncommon and multi-resistant bacteria that must be considered when treating infections such as post-injection endophthalmitis.
Topics: Humans; Morganella morganii; Enterococcus faecalis; Intravitreal Injections; Eye Infections, Bacterial; Endophthalmitis; Anti-Bacterial Agents; Vitrectomy; Bacteria; Retrospective Studies
PubMed: 37950172
DOI: 10.1186/s12886-023-03198-4 -
Journal of the Association of Medical... Sep 2023There is a paucity of studies investigating the population-based epidemiology of (MPP) group infections. Our objective was to determine the incidence, risk factors, and...
BACKGROUND
There is a paucity of studies investigating the population-based epidemiology of (MPP) group infections. Our objective was to determine the incidence, risk factors, and outcome of MPP group bloodstream infections (BSI), and explore species-specific differences.
METHODS
Population-based surveillance was conducted in the western interior of British Columbia, Canada, between April 1, 2010 and March 30, 2020.
RESULTS
Sixty-two incident MPP group BSI occurred for an annual incidence of 3.4 per 100,000 residents; rates for , , and species were 0.5, 2.6, and 0.3 per 100,000 population, respectively. The median year of age was 72.5 and was different ( = 0.03) among the groups. Most (92%) MPP group BSIs were of community-onset. Significant differences were observed in the distribution of clinical focus of infection, with most notably 81% of BSI due to genitourinary focus as compared to 60% and 22% for species and , respectively. Comorbid illnesses that increased the risk for development of MPP group BSI (incidence rate ratio; 95% CI) were HIV infection (37.0; 4.4-139.6), dementia (11.5; 6.1-20.7), cancer (6.4; 3.2-11.9), stroke 6.5 (2.8-13.3), and diabetes 2.7 (1.3-5.0). Thirteen, one, and none of the cases with , , and species BSI died within 30 days of index culture for respective all cause case-fatalities of 27%, 11%, and 0% ( = 0.1).
CONCLUSIONS
Although collectively responsible for a substantial burden of illness, the epidemiology of MPP group BSI varies significantly by species.
PubMed: 38250289
DOI: 10.3138/jammi-2022-0038 -
MSystems Jun 2024, encompassing two subspecies, and , is a common opportunistic pathogen, notable for intrinsic resistance to multiple antimicrobial agents. Despite its clinical...
, encompassing two subspecies, and , is a common opportunistic pathogen, notable for intrinsic resistance to multiple antimicrobial agents. Despite its clinical significance, research into the potential evolutionary dynamics of remains limited. This study involved the analysis of genome sequences from 431 . isolates, comprising 206 isolates that cause host infections, obtained from this study and 225 from the NCBI genome data sets. A diverse array of antimicrobial resistance genes (ARGs) was identified in isolates, including , (X4), , and various carbapenemase genes. In addition, a novel -bearing plasmid with demonstrated conjugative capability was discovered in . The majority of virulence-related genes (VRGs), except for the gene cluster, were found in almost all . Three novel genospecies of were identified, designated as , , and . Compared to , genospecies possessed a greater number of flagellar-related genes, typically located within mobile genetic elements (MGEs), suggesting potential for better environmental adaptability. Phylogenetic analysis further disclosed that was divided into 12 sequence clusters (SCs). Particularly, SC9 harbored an elevated abundance of ARGs and VRGs, mainly toxin-related genes, and was associated with a higher presence of MGEs compared to non-SC9 strains. The collective findings suggest that undergoes evolution driven by the influence of MGEs, thereby significantly enhancing its adaptability to selective pressures of environmental changes and clinical antimicrobial agents.IMPORTANCEThe growing clinical significance of arises from its abundant virulence factors and antimicrobial resistance genes, resulting in elevated infection rates and increased clinical scrutiny. However, research on the molecular epidemiology and evolutionary trends of has been scarce. Our study established a list of virulence-related genes (VRGs) for and conducted a large-scale epidemiological investigation into these VRGs. Based on genomic classification, three novel genotypes of were identified, representing evolutionary adaptations and responses to environmental challenges. Furthermore, we discovered the emergence of a sequence cluster enriched with antimicrobial resistance genes, VRGs, and mobile genetic elements, attributed to the selective pressure of antimicrobial agents. In addition, we identified a novel conjugative plasmid harboring the gene. These findings hold significance in monitoring and comprehending the epidemiology of .
PubMed: 38884495
DOI: 10.1128/msystems.00306-24 -
Journal of Biomolecular Structure &... Jul 2023is a Gram-negative bacterial pathogen that causes bacteremia, urinary tract infections, intra-abdominal infections, chorioamnionitis, neonatal sepsis, and newborn...
is a Gram-negative bacterial pathogen that causes bacteremia, urinary tract infections, intra-abdominal infections, chorioamnionitis, neonatal sepsis, and newborn meningitis. To control this bacterial pathogen a total of 3565 putative proteins targets in were screened using comparative subtractive analysis of biochemical pathways annotated by the KEGG that did not share any similarities with human proteins. One of the targets, D-alanyl-D-alanine carboxypeptidase DacB [] was observed to be implicated in the majority of cell wall synthesis pathways, leading to its selection as a novel pharmacological target. The drug that interacted optimally with the identified target was observed to be Cefoperazone (DB01329) with the estimated free energy of binding -8.9 Kcal/mol. During molecular dynamics simulations; it was observed that DB01328-2exb and DB01329-2exb complexes showed similar values as the control FMX-2exb complex near 0.2 nm with better stability. Furthermore, MMPBSA total free energy calculation showed better binding energy than the control complex for DB01329-2exb interaction i.e. -31.50 (±0.93) kcal/mol. Our presented research suggested that D-alanyl-D-alanine carboxypeptidase DacB could be a therapeutic target and cefoperazone could be a promising ligand to inhibit the D-alanyl-D-alanine carboxypeptidase DacB protein of . To identify prospective therapeutic and vaccine targets in , this is the first computational and subtractive genomics investigation of various metabolic pathways exploring other therapeutic targets of experimental validation of the identified target D-alanyl-D-alanine carboxypeptidase and the design of its inhibitors is suggested to figure out the best dose, the drug's effectiveness, and its toxicity.Communicated by Ramaswamy H. Sarma.
PubMed: 37480259
DOI: 10.1080/07391102.2023.2238088 -
Antibiotics (Basel, Switzerland) May 2024Carbapenemase-producing spp. , , spp., and (CP-ESCPM) are increasingly identified as causative agents of nosocomial infections but are still not under systematic...
Carbapenemase-producing spp. , , spp., and (CP-ESCPM) are increasingly identified as causative agents of nosocomial infections but are still not under systematic genomic surveillance. In this study, using a combination of whole-genome sequencing and conjugation experiments, we sought to elucidate the genomic characteristics and transferability of resistance genes in clinical CP-ESCPM isolates from Bulgaria. Among the 36 sequenced isolates, NDM-1 (12/36), VIM-4 (11/36), VIM-86 (8/36), and OXA-48 (7/36) carbapenemases were identified; two isolates carried both NDM-1 and VIM-86. The majority of carbapenemase genes were found on self-conjugative plasmids. IncL plasmids were responsible for the spread of OXA-48 among , , and . IncM2 plasmids were generally associated with the spread of NDM-1 in and , and also of VIM-4 in . IncC plasmids were involved in the spread of the recently described VIM-86 in isolates. IncC plasmids carrying and were observed too. was also detected on IncX3 in and on IncT plasmid in . The significant resistance transfer rates we observed highlight the role of the ESCPM group as a reservoir of resistance determinants and stress the need for strengthening infection control measures.
PubMed: 38786183
DOI: 10.3390/antibiotics13050455 -
Veterinary Sciences May 2024A bacterium was isolated and identified from the secretion of a rhesus monkey with endometritis. The morphological results showed that the strain exhibited round,...
A bacterium was isolated and identified from the secretion of a rhesus monkey with endometritis. The morphological results showed that the strain exhibited round, convex, gray-white colonies with smooth surfaces and diameters ranging from 1 to 2 mm when cultured on Columbia blood agar at 37 °C for 24 h; on salmonella-shigella agar (S.S.) at 37 °C for 24 h, the colonies appeared round, flat, and translucent. Gram staining showed negative results with blunt ends and non-spore-forming characteristics. Molecular biology results showed that the 16S rRNA sequence of the strain revealed over 96.9% similarity with published sequences of from different sources in the NCBI GenBank database. Morphological and molecular biology analysis confirmed that the strain (RM2023) isolated from cervical secretions of rhesus monkey was . Drug sensitivity testing demonstrated that the isolated strain (RM2023) was sensitive to ceftriaxone, amikacin, gentamicin, cefazolin, cefuroxime, ceftazidime, levofloxacin, cotrimoxazole, norfloxacin, and tetracycline; moderately sensitive to ampicillin; and resistant to penicillin, vancomycin, ciprofloxacin, and clindamycin. The research findings provide valuable insights for disease prevention in rhesus monkeys and contribute to molecular epidemiological studies.
PubMed: 38787195
DOI: 10.3390/vetsci11050223