A sialidase (neuraminidase, acylneuraminosyl hydrolase, EC 3.2.1.18) has been discovered and isolated from Gardnerella vaginalis (ex. Haemophilus vaginalis), a possibly pathogenic inhabitant of the female genital tract. Bacteria were grown in peptone-yeast-extract medium with 2.0 mM N-acetylmannosamine as enzyme inductor under CO2 atmosphere. Sialidase activity was found in the bacterial sediment and in the culture medium. The enzyme was liberated from the cells by ultrasonic treatment. Purification was performed by 60-80% ammonium sulfate precipitation and by column chromatography on Sepharose CL-6B and Sephadex G 200. The enzyme revealed a molecular weight in the range of Mr 75 000 and a pH optimum at 5.5. Among the different types of NeuAc-containing glycoconjugates, the enzyme exhibits its highest activities towards the globular glycoproteins alpha 1-acid glycoprotein and fetuin. Taking their cleavage rate as 100, it is around 55 for II3NeuAc-Lac, 45 for bovine submaxillary mucin, 35 for II6NeuAc-Lac and IV3, III6NeuAc2-LcOse4. The rates for III8,II3NeuAc2-Lac, gangliosides and colominic acid are below 20. Due to its specificity pattern, the enzyme may play a role in the pathogenic process of G. vaginalis infections.
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http://dx.doi.org/10.1016/s0176-6724(84)80003-6 | DOI Listing |
Microbiome
January 2025
Department of Medicine, University of Toronto, Toronto, Canada.
Background: Genital inflammation increases HIV susceptibility and is associated with the density of pro-inflammatory anaerobes in the vagina and coronal sulcus. The penile urethra is a critical site of HIV acquisition, although correlates of urethral HIV acquisition are largely unknown. While Streptococcus mitis is a consistent component of the urethral flora, the presence of Gardnerella vaginalis has been linked with prior penile-vaginal sex and urethral inflammation.
View Article and Find Full Text PDFBiofilm
June 2025
Centre of Biological Engineering (CEB), Laboratory of Research in Biofilms Rosário Oliveira (LIBRO), University of Minho, Braga, Portugal.
Bacterial vaginosis (BV) is a very common gynaecologic condition affecting women of reproductive age worldwide. BV is characterized by a depletion of lactic acid-producing species and an increase in strict and facultative anaerobic bacteria that develop a polymicrobial biofilm on the vaginal epithelium. Despite multiple decades of research, the etiology of this infection is still not clear.
View Article and Find Full Text PDFMicroorganisms
January 2025
Unidad de Investigación en Salud, Hospital de Alta Especialidad Ixtapaluca, IMSS-Bienestar, Carr Federal México-Puebla Km 34.5, Ixtapaluca 56530, Mexico.
Unlabelled: Infertility, both primary and secondary, is strongly influenced by microbiological factors, with the vaginal microbiota playing a key role in reproductive health.
Objective: The aim of this study was to characterize the vaginal microbiota of 136 Mexican women diagnosed with infertility-primary (n = 58) and secondary (n = 78)-by evaluating the presence of pathogenic bacterial species and their associations with infertility conditions.
Methods: Samples were obtained through cervical swabs, and microorganism identification was performed using qPCR techniques.
Microorganisms
January 2025
Hospital Juárez de México, Mexico City 07760, Mexico.
Pyogenic liver abscesses (PLAs) are serious infections in which doctors often fail in identifying the causative agent due to microbiological limitations. These limitations in detecting uncommon pathogens complicate the treatment and recovery. Molecular techniques, like massive sequencing, enable the detection of uncommon pathogens and highlight the shortcomings of traditional cultures.
View Article and Find Full Text PDFFront Immunol
January 2025
Microbiome-X, School of Public Health, Cheeloo College of Medicine, Shandong University, Jinan, China.
[This corrects the article DOI: 10.3389/fimmu.2024.
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