Whole-genome sequencing of serotype M3 group A streptococci (GAS) from oropharyngeal and invasive infections in Ontario recently showed that the gene encoding regulator of protease B (RopB) is highly polymorphic in this population. To test the hypothesis that ropB is under diversifying selective pressure among all serotype M3 GAS strains, we sequenced this gene in 1178 strains collected from different infection types, geographic regions, and time periods. The results confirmed our hypothesis and discovered a significant association between mutant ropB alleles, decreased activity of its major regulatory target SpeB, and pharyngitis. Additionally, isoallelic strains with ropB polymorphisms were significantly less virulent in a mouse model of necrotizing fasciitis. These studies provide a model strategy for applying whole-genome sequencing followed by deep single-gene sequencing to generate new insight to the rapid evolution and virulence regulation of human pathogens.
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http://dx.doi.org/10.1093/infdis/jir825 | DOI Listing |
Acta Physiol (Oxf)
February 2025
Henan Key Laboratory of Medical Tissue Regeneration, Xinxiang Medical University, Xinxiang, China.
Cardiovascular diseases (CVD) are the leading cause of morbidity and mortality globally, with elevated low-density lipoprotein cholesterol (LDL-C) levels being a major risk factor. Proprotein convertase subtilisin/kexin type 9 (PCSK9) plays a critical role in regulating LDL-C levels by promoting the degradation of hepatic low-density lipoprotein receptors (LDLR) responsible for clearing LDL-C from the circulation. PCSK9 inhibitors are novel lipid-modifying agents that have demonstrated remarkable efficacy in reducing plasma LDL-C levels and decreasing the incidence of CVD.
View Article and Find Full Text PDFNutrients
January 2025
Key Laboratory of Geriatric Nutrition and Health, Ministry of Education, China-Canada Joint Lab of Food Nutrition and Health, Key Laboratory of Special Food Supervision Technology for State Market Regulation, Beijing Technology and Business University, Beijing 100048, China.
Organ fibrosis is gradually becoming a human health and safety problem, and various organs of the body are likely to develop fibrosis. The ultimate pathological feature of numerous chronic diseases is fibrosis, and few interventions are currently available to specifically target the pathogenesis of fibrosis. The medical detection of organ fibrosis has gradually matured.
View Article and Find Full Text PDFNutrients
December 2024
Key Laboratory of Environmental Medicine and Engineering of Ministry of Education, Department of Nutrition and Food Hygiene, School of Public Health, Southeast University, Nanjing 210009, China.
Food protein-derived antihypertensive peptides have attracted substantial attention as a safer alternative for drugs. The regulation of the renin-angiotensin system (RAS) is an essential aspect underlying the mechanisms of antihypertensive peptides. Most of the identified antihypertensive peptides exhibit the angiotensin-converting enzyme (ACE) inhibitory effect.
View Article and Find Full Text PDFInt J Mol Sci
January 2025
Department of Biosciences and Bioinformatics, School of Science, Xi'an Jiaotong-Liverpool University, Suzhou 215123, China.
Melatonin is a hormone released by the pineal gland that regulates the sleep-wake cycle. It has been widely studied for its therapeutic effects on Alzheimer's disease (AD), particularly through the amyloidosis, oxidative stress, and neuroinflammation pathways. Nevertheless, the mechanisms through which it exerts its neuroprotective effects in AD are still largely unknown.
View Article and Find Full Text PDFInt J Mol Sci
January 2025
Research Department, Royal College of Surgeons of Ireland, Adliya 15503, Bahrain.
Matrix metalloproteinases (MMPs) are M2 macrophage markers that are modulated by inflammation. A disintegrin and metalloproteinases (ADAMS) and those with thrombospondin motifs (ADAMTS) regulate the shedding of membrane-bound proteins, growth factors, cytokines, ligands, and receptors; MMPs, ADAMS, and ADAMTS may be regulated by tissue inhibitors of metalloproteinases (TIMPs). This study aimed to determine whether these interacting proteins were dysregulated in PCOS.
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