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Animals : An Open Access Journal From... May 2024is a common tick species that carries several pathogens. There are few reports on the influence of different hosts on the structure of midgut microflora in . In this...
is a common tick species that carries several pathogens. There are few reports on the influence of different hosts on the structure of midgut microflora in . In this study, midgut contents of fully engorged female were collected from the surface of tiger () and deer (). The bacterial genomic DNA of each sample was extracted, and the V3-V4 regions of the bacterial 16S rRNA were sequenced using the Illumina NovaSeq sequencing. The diversity of the bacterial community of the fully engorged female on the surface of tiger was higher than that of deer. In total, 8 phyla and 73 genera of bacteria annotations were detected in the two groups. At the phylum level, the bacterial phyla common to the two groups were Proteobacteria, Firmicutes, and Actinobacteriota. At the genus level, there were 20 common bacterial genera, among which the relative abundances of , , , and were high. The species was further identified to be . The alpha diversity index indicated that the bacterial diversity of the tiger group was higher than that of the deer group. Bacteroidota, Patescibacteria, Desulfobacterota, Verrucomicrobiota, and Cyanobacteria were solely detected in the tiger group. A total of 52 bacterial genera were unique in the tiger group, while one bacterial genus was unique in the deer group. This study indicates that there are differences in the structure of the gut bacteria of the same tick species among different hosts. Further culture-based methods are needed to provide a more comprehensive understanding of the tick microbiota parasitizing different hosts.
PubMed: 38891605
DOI: 10.3390/ani14111557 -
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 -
Cureus May 2024Diabetic foot ulcers represent a significant complication of diabetes mellitus, characterized by mechanical changes of bony architecture often leading to chronic wounds...
Diabetic foot ulcers represent a significant complication of diabetes mellitus, characterized by mechanical changes of bony architecture often leading to chronic wounds with increased risk of infection and impaired healing. , a Gram-negative bacterium, is one of the pathogens found in infected diabetic foot ulcers. It is a human gastrointestinal commensal organism that may cause widespread deadly infections. This report discusses the case of a 76-year-old male with diabetes mellitus who presented with diabetic foot ulcer to an in-patient rehabilitation facility. Despite conventional wound care and antibiotic therapy, the ulcer failed to improve. The management approach for this patient consisted of a rehabilitation modality called Vaporox, a machine that utilizes vaporous hyperoxia therapy (VHT), as it combines ultrasonic mist and high concentration of oxygen to fasten revascularization and healing. This case highlights the potential efficacy of VHT as an adjunctive therapy for the management of diabetic foot ulcers, particularly those complicated by pathogens, such as .
PubMed: 38883037
DOI: 10.7759/cureus.60413 -
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 -
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 -
Cureus Apr 2024Purple urine bag syndrome (PUBS) is a rare manifestation of urinary tract infection (UTI) characterized by bluish-purple discoloration of urine, typically seen in...
Purple urine bag syndrome (PUBS) is a rare manifestation of urinary tract infection (UTI) characterized by bluish-purple discoloration of urine, typically seen in patients with long-term urinary catheters. It occurs due to the bacterial metabolism of dietary tryptophan into indole, which is converted into indoxyl sulfate in the liver and then excreted in the urine, where it reacts with catheter materials under alkaline conditions. Risk factors include chronic constipation, advanced age, female gender, dehydration, and recurrent UTIs. is one of the bacteria commonly implicated. Although usually benign, PUBS can signal underlying UTIs, especially in asymptomatic patients. The case presented involves an 81-year-old woman with a history of urothelial carcinoma and a monoJ catheter since pelvic exenteration and ureterostomy. She presented with blue-colored urine in the collection bag; she was asymptomatic, but the urinalysis had leukocytes, nitrites and alkaline pH, and the uroculture was positive for . Antibiotic therapy resolved the symptoms initially, but recurrence prompted further treatment and optimization of constipation management. PUBS, although rare, poses risks, especially in vulnerable populations. Identification of risk factors and causative agents is crucial for effective treatment, typically involving catheter replacement, antimicrobial therapy, and constipation correction. Prevention focuses on minimizing catheter use, regular replacement, and hygiene optimization. Early recognition and management in primary care settings can prevent complications and reduce patient and caregiver distress. In conclusion, PUBS is a visually evident condition that may serve as an early indication of UTI, particularly in patients with chronic catheterization. Treatment and prevention strategies should be tailored to individual risk factors to prevent the recurrence or persistence of the syndrome. Awareness among healthcare professionals and patients is essential for timely diagnosis and management. The presented case demonstrates the importance of primary care in managing complex conditions and highlights the close patient-physician relationship in such settings.
PubMed: 38707090
DOI: 10.7759/cureus.57620 -
The Lancet. Microbe Jun 2024Morganella spp are opportunistic pathogens involved in various infections. Intrinsic resistance to multiple antibiotics (including colistin) combined with the emergence... (Comparative Study)
Comparative Study
BACKGROUND
Morganella spp are opportunistic pathogens involved in various infections. Intrinsic resistance to multiple antibiotics (including colistin) combined with the emergence of carbapenemase producers reduces the number of active antimicrobials. The aim of this study was to characterise genetic features related to the spread of carbapenem-resistant Morganella spp.
METHODS
This comparative genomic study included extensively drug-resistant Morganella spp isolates collected between Jan 1, 2013, and March 1, 2021, by the French National Reference Center (NRC; n=68) and European antimicrobial resistance reference centres in seven European countries (n=104), as well as one isolate from Canada, two reference strains from the Pasteur Institute collection (Paris, France), and two colistin-susceptible isolates from Bicêtre Hospital (Kremlin-Bicêtre, France). The isolates were characterised by whole-genome sequencing, antimicrobial susceptibility testing, and biochemical tests. Complete genomes from GenBank (n=103) were also included for genomic analysis, including phylogeny and determination of core genomes and resistomes. Genetic distance between different species or subspecies was performed using average nucleotide identity (ANI). Intrinsic resistance mechanisms to polymyxins were investigated by combining genetic analysis with mass spectrometry on lipid A.
FINDINGS
Distance analysis by ANI of 275 isolates identified three groups: Morganella psychrotolerans, Morganella morganii subspecies sibonii, and M morganii subspecies morganii, and a core genome maximum likelihood phylogenetic tree showed that the M morganii isolates can be separated into four subpopulations. On the basis of these findings and of phenotypic divergences between isolates, we propose a modified taxonomy for the Morganella genus including four species, Morganella psychrotolerans, Morganella sibonii, Morganella morganii, and a new species represented by a unique environmental isolate. We propose that M morganii include two subspecies: M morganii subspecies morganii (the most prevalent) and M morganii subspecies intermedius. This modified taxonomy was supported by a difference in intrinsic resistance to tetracycline and conservation of metabolic pathways such as trehalose assimilation, both only present in M sibonii. Carbapenemase producers were mostly identified among five high-risk clones of M morganii subspecies morganii. The most prevalent carbapenemase corresponded to NDM-1, followed by KPC-2, and OXA-48. A cefepime-zidebactam combination was the most potent antimicrobial against the 172 extensively drug-resistant Morganella spp isolates in our collection from different European countries, which includes metallo-β-lactamase producers. Lipid A analysis showed that the intrinsic resistance to colistin was associated with the presence of L-ARA4N on lipid A.
INTERPRETATION
This global characterisation of, to our knowledge, the widest collection of extensively drug-resistant Morganella spp highlights the need to clarify the taxonomy and decipher intrinsic resistance mechanisms, and paves the way for further genomic comparisons.
FUNDING
None.
Topics: Bacterial Proteins; beta-Lactamases; Anti-Bacterial Agents; Genome, Bacterial; Microbial Sensitivity Tests; Humans; Phylogeny; Enterobacteriaceae Infections; Morganella; Genomics; Whole Genome Sequencing; Europe; Carbapenems; Drug Resistance, Multiple, Bacterial; Colistin
PubMed: 38677305
DOI: 10.1016/S2666-5247(23)00407-X -
Journal of Insect Science (Online) Mar 2024Larval habitats of blood-feeding stable flies, Stomoxys calcitrans (L.) (Diptera: Muscidae), overlap with foraging sites of black blow flies, Phormia regina (Meigen)...
Larval habitats of blood-feeding stable flies, Stomoxys calcitrans (L.) (Diptera: Muscidae), overlap with foraging sites of black blow flies, Phormia regina (Meigen) (Diptera: Calliphoridae). We tested the hypothesis that bacteria in blow fly excreta inform oviposition decisions by female stable flies. In laboratory 2-choice bioassays, we offered gravid female stable flies fabric-covered agar plates as oviposition sites that were kept sterile or inoculated with either a blend of 7 bacterial strains isolated from blow fly excreta (7-isolate-blend) or individual bacterial isolates from that blend. The 7-isolate-blend deterred oviposition by female stable flies, as did either of 2 strains of Morganella morganii subsp. sibonii. Conversely, Exiguobacterium sp. and Serratia marcescens each prompted oviposition by flies. The flies' oviposition decisions appear to be guided by bacteria-derived semiochemicals as the bacteria could not be physically accessed. Oviposition deterrence caused by semiochemicals of the 7-isolate-blend may help stable flies avoid competition with blow flies. The semiochemicals of bioactive bacterial strains could be developed as trap lures to attract and capture flies and deter their oviposition in select larval habitats.
Topics: Female; Animals; Muscidae; Calliphoridae; Oviposition; Larva; Bacteria; Pheromones; Morganella
PubMed: 38597910
DOI: 10.1093/jisesa/ieae040 -
Microorganisms Feb 2024Venous leg ulcers (VLUs) are a common chronic wound condition susceptible to infection by various bacterial species. Understanding bacterial presence and antibiotic...
Bacterial Species Involved in Venous Leg Ulcer Infections and Their Sensitivity to Antibiotherapy-An Alarm Signal Regarding the Seriousness of Chronic Venous Insufficiency C6 Stage and Its Need for Prompt Treatment.
Venous leg ulcers (VLUs) are a common chronic wound condition susceptible to infection by various bacterial species. Understanding bacterial presence and antibiotic sensitivity is crucial for effective treatment. Methodsː Medical records of 60 patients diagnosed with the C6 chronic venous insufficiency stage were analyzed retrospectively. The patients were divided into an active recurrent VLU group (33 cases) and a first-onset active VLU group (27 cases). Bacterial identification, antibiotic sensitivity, and laboratory markers were assessed. Resultsː was the most prevalent bacterial species in both the study (72.72%) and control (37.03%) groups, along with other common bacteria such as , sp., , , spp., and . Furthermore, uncommon bacteria, including , , and , and a fungal infection with , were identified only in the study group, while was found exclusively in the control group. showed significant sensitivity to several antibiotics, particularly Amikacin and Meropenem. Nonspecific laboratory markers, such as CRP, fibrinogen, ESR, WBC, CK, neutrophils, and lymphocytes, revealed statistically significant differences between groups, indicating their potential as biomarkers for monitoring recurrent VLUs. Conclusionsː These results highlight the need for comprehensive diagnostic approaches to effectively manage VLU infections and improve patient outcomes. Further research is warranted to explore factors influencing the presence of uncommon bacteria and to develop targeted interventions for VLU management.
PubMed: 38543523
DOI: 10.3390/microorganisms12030472 -
Pathogens (Basel, Switzerland) Mar 2024Urinary tract infections occupy a special niche among diseases of infectious etiology. Many microorganisms associated with urinary tract infections, such as , spp., , ,...
Urinary tract infections occupy a special niche among diseases of infectious etiology. Many microorganisms associated with urinary tract infections, such as , spp., , , , , , spp., and spp., can form biofilms. The aim of this research was to study the effect of the enzyme L-lysine-Alpha-oxidase (LO) produced by the fungus on the biofilm formation process of microorganisms associated with urinary tract infections. Homogeneous LO showed a more pronounced effect than the culture liquid concentrate (cCL). When adding samples at the beginning of incubation, the maximum inhibition was observed in relation to 5960-cCL 86%, LO 95%; 1669-cCL 85%, LO 94%; 6392-cCL 83%, LO-98%; and 3057-cCL 70%, LO-82%. The minimum inhibition was found in spp. Scanning electron microscopy was carried out, and numerous morphological and structural changes were observed in the cells after culturing the bacterial cultures in a medium supplemented with homogeneous LO. For example, abnormal division was detected, manifesting as the appearance of joints in places where the bacteria diverge. Based on the results of this work, we can draw conclusions about the possibility of inhibiting microbial biofilm formation with the use of LO; especially significant inhibition was achieved when the enzyme was added at the beginning of incubation. Thus, LO can be a promising drug candidate for the treatment or prevention of infections associated with biofilm formation.
PubMed: 38535596
DOI: 10.3390/pathogens13030252