The xanthine oxidases and dehydrogenases are among the most conserved enzymes in all living kingdoms. They contain the molybdopterin cofactor Moco. We show here that in the fungi, in addition to xanthine dehydrogenase, a completely different enzyme is able to catalyse the oxidation of xanthine to uric acid. In Aspergillus nidulans this enzyme is coded by the xanA gene. We have cloned the xanA gene and determined its sequence. A deletion of the gene has the same phenotype as the previously known xanA1 miss-sense mutation. Homologues of xanA exist only in the fungal kingdom. We have inactivated the cognate gene of Schizosaccharomyces pombe and this results in strongly impaired xanthine utilization as a nitrogen source. We have shown that the Neurospora crassa homologue is functionally equivalent to xanA. The enzyme coded by xanA is an alpha-ketoglutarate- and Fe(II)-dependent dioxygenase which shares a number of properties with other enzymes of this group. This work shows that only in the fungal kingdom, an alternative mechanism of xanthine oxidation, not involving Moco, has evolved using the dioxygenase scaffold.
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http://dx.doi.org/10.1111/j.1365-2958.2005.04686.x | DOI Listing |
Crit Rev Microbiol
January 2025
Oral Microbiology, Bristol Dental School, University of Bristol, United Kingdom.
This review discusses the chemical properties, synthesis and detection, and biological functions of a molecular group of cis-2-unsaturated fatty acids, containing fatty acid carbon chains of various lengths and cis double-bond configurations, known as the diffusible signaling factor family (DSFF). Early postulation of the conserved nature of the DSFF among Gram-negative bacteria have now been challenged by the latest evidences that unraveled their presence in a various other distinct microorganisms. Over the last decade, a significant depth and breadth of understanding has been made on the multifaceted functions of DSFFs among bacteria, and their interactions with evolutionarily divergent fungi, plants insects and small animals.
View Article and Find Full Text PDFTranspl Int
January 2025
Department of Microbiology, Immunology and Transplantation, KU Leuven, Leuven, Belgium.
Highly sensitized (HS) patients in need of kidney transplantation (KTx) typically spend a longer time waiting for compatible kidneys, are unlikely to receive an organ offer, and are at increased risk of antibody-mediated rejection (AMR). Desensitization using imlifidase, which is more rapid and removes total body immunoglobulin G (IgG) to a greater extent than other methods, enables transplantation to occur between HLA-incompatible (HLAi) donor-recipient pairs and allows patients to have greater access to KTx. However, when the project was launched there was limited data and clinical experience with desensitization in general and with imlifidase specifically.
View Article and Find Full Text PDFFront Pediatr
January 2025
Department of Public Health Pharmacy and Management, School of Pharmacy, Sefako Makgatho Health Sciences University, Ga-Rankuwa, South Africa.
Introduction: Surveillance of antibiotic use is crucial for identifying targets for antibiotic stewardship programs (ASPs), particularly in pediatric populations within countries like Pakistan, where antimicrobial resistance (AMR) is escalating. This point prevalence survey (PPS) seeks to assess the patterns of antibiotic use in pediatric patients across Punjab, Pakistan, employing the WHO AWaRe classification to pinpoint targets for intervention and encourage rational antibiotic usage.
Methods: A PPS was conducted across 23 pediatric wards of 14 hospitals in the Punjab Province of Pakistan using the standardized Global-PPS methodology developed by the University of Antwerp.
Front Plant Sci
January 2025
Institute of Biological, Environmental and Rural Sciences (IBERS) Aberystwyth University, Aberystwyth, United Kingdom.
Nitrogen and water are the primary resources limiting agricultural production worldwide. We have demonstrated the ability of a novel halotolerant bacterial endophyte, s CBE, to induce osmotic stress tolerance in under nitrogen-deprived conditions. Additionally, we aimed to identify the molecular factors in plants that contribute to the beneficial effects induced by CBE in .
View Article and Find Full Text PDFEnviron Microbiol
January 2025
Department of Biology, University of Oxford, Oxford, UK.
Rhizobia and legumes form a symbiotic relationship resulting in the formation of root structures known as nodules, where bacteria fix nitrogen. Legumes release flavonoids that are detected by the rhizobial nodulation (Nod) protein NodD, initiating the transcriptional activation of nod genes and subsequent synthesis of Nod Factors (NFs). NFs then induce various legume responses essential for this symbiosis.
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