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International Journal of Molecular... Jun 2024is an important opportunistic pathogenic bacterium widely distributed in the environment. Pyolysin (PLO) is a primary virulence factor of and capable of lysing many...
is an important opportunistic pathogenic bacterium widely distributed in the environment. Pyolysin (PLO) is a primary virulence factor of and capable of lysing many different cells. PLO is a member of the cholesterol-dependent cytolysin (CDC) family of which the primary structure only presents a low level of homology with other members from 31% to 45%. By deeply studying PLO, we can understand the overall pathogenic mechanism of CDC family proteins. This study established a mouse muscle tissue model infected with recombinant PLO (rPLO) and its single-point mutations, rPLO N139K and rPLO F240A, and explored its mechanism of causing inflammatory damage. The inflammatory injury abilities of rPLO N139K and rPLO F240A are significantly reduced compared to rPLO. This study elaborated on the inflammatory mechanism of PLO by examining its unit point mutations in detail. Our data also provide a theoretical basis and practical significance for future research on toxins and bacteria.
Topics: Animals; Point Mutation; Mice; Hemolysin Proteins; NLR Family, Pyrin Domain-Containing 3 Protein; Bacterial Proteins; Inflammation; Potassium; Signal Transduction; Bacterial Toxins; Inflammasomes; Humans
PubMed: 38928408
DOI: 10.3390/ijms25126703 -
Animals : An Open Access Journal From... May 2024is a Gram-positive fastidious bacterium and is occasionally isolated from the reproductive tract of apparently healthy mares () or from mares with reproductive tract...
is a Gram-positive fastidious bacterium and is occasionally isolated from the reproductive tract of apparently healthy mares () or from mares with reproductive tract abnormalities. Apart from a few 16S rRNA gene-based GenBank sequences and one recent report on complete genome assembly, detailed genomic sequence and clinical experimental data are not available on the bacterium. Recently, we observed an unusual increase in the detection of the organism from samples associated with mare reproductive failures in Atlantic Canada. Two colony morphotypes (i.e., small, and large) were detected in culture media, which were identified as by MALDI-TOF mass spectrometry and 16S rRNA gene sequencing. Here, we report the whole genome sequencing and characterization of the morphotype variants. The genome length of the large phenotypes was between 2.42 and 2.43, and the small phenotype was 1.99 Mbs. The orthologous nucleotide identity between the large colony phenotypes was ~99%, and the large and small colony phenotypes was between 77.86 and 78.52%, which may warrant the classification of the two morphotypes into different species. Phylogenetic analysis based on 16S rRNA genes or concatenated housekeeping genes grouped the small and large colony variants into two different genotypic clusters. The UvrA protein, which is part of the nucleotide excision repair (NER) system, and 3-isopropoylmalate dehydratase small subunit protein expressed by the gene were identified as potential virulence factors in the large and small colony morphotypes, respectively. However, detailed functional studies will be required to determine the exact roles of these and other identified hypothetical proteins in the cellular metabolism and potential pathogenicity of in mares.
PubMed: 38891657
DOI: 10.3390/ani14111609 -
New Microbes and New Infections Jun 2024
Expression of Concern: Arcanobacterium ihumii sp. nov., Varibaculum vaginae sp. nov. and Tessaracoccus timonensis sp. nov., isolated from vaginal swabs from healthy Senegalese women.
PubMed: 38799966
DOI: 10.1016/j.nmni.2024.101259 -
New Microbes and New Infections Jun 2024
PubMed: 38799955
DOI: 10.1016/j.nmni.2024.101396 -
New Microbes and New Infections Jun 2024
PubMed: 38799916
DOI: 10.1016/j.nmni.2024.101260 -
Microbial Genomics May 2024Cutaneous ulcers are common in yaws-endemic areas. Although often attributed to ' subsp. and , quantitative PCR has highlighted a significant proportion of these ulcers...
Using 16s rRNA sequencing to characterize the microbiome of tropical cutaneous ulcer disease: insights into the microbial landscape and implications for diagnosis and treatment.
Cutaneous ulcers are common in yaws-endemic areas. Although often attributed to ' subsp. and , quantitative PCR has highlighted a significant proportion of these ulcers are negative for both pathogens and are considered idiopathic. This is a retrospective analysis utilising existing 16S rRNA sequencing data from two independent yaws studies that took place in Ghana and the Solomon Islands. We characterized bacterial diversity in 38 samples to identify potential causative agents for idiopathic cutaneous ulcers. We identified a diverse bacterial profile, including , , , spp and , consistent with findings from previous cutaneous ulcer microbiome studies. No single bacterial species was universally present across all samples. The most prevalent bacterium, , appeared in 42% of samples, suggesting a multifactorial aetiology for cutaneous ulcers in yaws-endemic areas. This study emphasizes the need for a nuanced understanding of potential causative agents. The findings prompt further exploration into the intricate microbial interactions contributing to idiopathic yaw-like ulcers, guiding future research toward comprehensive diagnostic and therapeutic strategies.
Topics: Humans; RNA, Ribosomal, 16S; Microbiota; Skin Ulcer; Ghana; Male; Yaws; Retrospective Studies; Female; Adult; Bacteria; Melanesia; Middle Aged; Staphylococcus; Streptococcus pyogenes; Arcanobacterium; Campylobacter
PubMed: 38739120
DOI: 10.1099/mgen.0.001234 -
IDCases 2024This article describes a case of polymicrobial pharyngitis and sinusitis complicated by intracranial complications and reviews similar cases in the literature.
OBJECTIVE
This article describes a case of polymicrobial pharyngitis and sinusitis complicated by intracranial complications and reviews similar cases in the literature.
CASE SUMMARY
A 21-year-old immunocompetent male presented with symptoms of sore throat, rhinorrhoea, lethargy, headache, and rash. Imaging demonstrated sinusitis, pre-septal sinusitis, peritonsillar abscess formation, subdural empyema and cerebritis. He was managed with endoscopic sinus surgery, craniotomy for evacuation of subdural empyema and antibiotics. Microbiological samples demonstrated growth of , , and . He subsequently developed a cerebral abscess requiring stereotactic needle drainage. After a prolonged course of antibiotics, the patient was discharge and made a good recovery.
DISCUSSION
is an uncommon cause of non-streptococcal pharyngitis that may occur alongside other microorganisms and is rarely associated with severe intracranial complications. This organism and its antibiotic susceptibility patterns should be considered in complicated upper respiratory tract infections in immunocompetent hosts. Penicillins and macrolide antibiotics form the mainstay of therapy for .
PubMed: 38690576
DOI: 10.1016/j.idcr.2024.e01960 -
Radiology Case Reports Jul 2024, found as normal flora in healthy individuals, is an unusual culprit for pharyngitis and sinusitis in young adults, rarely leading to severe infections. Here, we...
, found as normal flora in healthy individuals, is an unusual culprit for pharyngitis and sinusitis in young adults, rarely leading to severe infections. Here, we present a singular case involving a 19-year-old immunocompetent male who experienced complications arising from sinusitis, leading to orbital and intracranial sinogenic complications. The patient developed severe cerebral vasospasm with delayed cerebral ischemia, necessitating aggressive management encompassing daily catheter-directed intra-arterial infusions, surgical source control, and maximal medical therapy. This case explores the challenging diagnostic and management aspects associated with cerebral artery vasospasm secondary to bacterial meningoencephalitis. The abrupt neurological decline in such patients presents a dilemma in recognizing the occurrence of cerebral vasospasm versus the progression of meningoencephalitis. By utilizing computed tomography brain perfusion scans, we were able to identify delayed cerebral ischemia due to cerebral vasospasm, acknowledging that this modality was not used to identify classical territorial stroke infarcts. This decision was made based on the understanding of the potential for bacterial-induced cerebral vasospasm to involve both hemispheres.
PubMed: 38645946
DOI: 10.1016/j.radcr.2024.03.029 -
Reproduction in Domestic Animals =... Apr 2024Pyometra is a prevalent and severe infectious disease that affects the reproductive systems of cattle worldwide. This study's main goal was to investigate the biomarkers...
Pyometra is a prevalent and severe infectious disease that affects the reproductive systems of cattle worldwide. This study's main goal was to investigate the biomarkers for oxidative stress (OS), adiponectin, leptin and neopterin (NPT) in cows suffering from postpartum pyometra. The study also aimed to determine which bacteria were most commonly implicated in the development of the disease. A total of 74 cows with pyometra were examined and compared to a control group of healthy cows (n = 20). In comparison to the healthy control and post-treatment groups, the pyometra group showed higher mean values of leptin, adiponectin and malondialdehyde (MDA). In contrast, the glutathione (GSH) and superoxide dismutase (SOD) mean values were lower in the pyometra group as compared to the post-treatment and control groups. NPT levels in the post-treatment groups were lower than those in cows with pyometra but comparable to the healthy control group (p > .05). When compared to the other biomarkers, NPT, leptin and adiponectin showed higher sensitivity and specificity in identifying pyometra cases (AUC ≥0.99). The predominant bacterial isolates from the ptomtra-affected cows consisted of Escherichia coli (N = 29; 39.2%), Arcanobacterium pyogenes (N = 27; 36.5%) and Fusobacterium necrophorum (N = 13; 17.6%). Mixed infection was determined in nine samples (12.2%). Conclusively, OS, adiponectin, leptin and NPT play crucial roles in comprehending the development of postpartum pyometra in cows and have the potential to serve as biomarkers for the disease.
Topics: Female; Cattle; Animals; Pyometra; Leptin; Adiponectin; Postpartum Period; Oxidative Stress; Glutathione; Biomarkers; Cattle Diseases
PubMed: 38591742
DOI: 10.1111/rda.14559