Expansion of Invasive Group A Streptococcus M1UK Lineage in Active Bacterial Core Surveillance, United States, 2019 ‒2021
Y. Li et al. (Source: Emerging Infectious Diseases Journal)
Source: Emerging Infectious Diseases Journal - August 28, 2023 Category: Infectious Diseases Source Type: research
RopB-regulated SpeB cysteine protease degrades extracellular vesicles-associated streptolysin O and bacterial proteins from group A Streptococcus
Volume 14, Issue 1, December 2023 . (Source: Virulence)
Source: Virulence - August 25, 2023 Category: Virology Authors: Chuan Chiang-Ni Chien-Yi Chiang Yan-Wen Chen Yong-An Shi Yu-Tzu Chao Shuying Wang Pei-Jane Tsai Cheng-Hsun Chiu Source Type: research
Insertion of an immunodominant T helper cell epitope within the Group A Streptococcus M protein promotes an IFN- γ-dependent shift from a non-protective to a protective immune response
In this study, we use a murine immunization model to investigate aspects of the cellular and molecular foundation for protective adaptive immune responses generated against GAS. We show that a wild type M1 GAS strain induces a non-protective antibody response, while an isogenic strain carrying the immunodominant 2W T helper cell epitope within the M protein elicits an immune response that is protective against the parental non-recombinant M1 GAS strain. Although the two strains induce total anti-GAS IgG levels of similar magnitude, only the 2W-carrying strain promotes elevated titers of the complement-fixing IgG2c subclass...
Source: Frontiers in Immunology - August 15, 2023 Category: Allergy & Immunology Source Type: research
Effectiveness of Intravenous Immunoglobulin Therapy for Invasive Group A Streptococcus Infection: A Japanese Nationwide Observational Study
Group A Streptococcus (GAS) is a Gram-positive, beta-hemolytic coccus. It can cause various diseases, ranging from mild illnesses (such as pharyngitis and impetigo) to severe illnesses (such as necrotizing fasciitis and streptococcal toxic shock syndrome (STSS)). Invasive group A Streptococcus infection (iGAS) is defined as the isolation of GAS from sterile sites including the blood, pleura, and cerebrospinal fluid [1]. (Source: International Journal of Infectious Diseases)
Source: International Journal of Infectious Diseases - August 14, 2023 Category: Infectious Diseases Authors: Atsushi Senda, Akira Endo, Kiyohide Fushimi, Yasuhiro Otomo Source Type: research
The protease associated (PA) domain in ScpA from Streptococcus pyogenes plays a role in substrate recruitment
Biochim Biophys Acta Proteins Proteom. 2023 Aug 8:140946. doi: 10.1016/j.bbapap.2023.140946. Online ahead of print.ABSTRACTAnnually, over 18 million disease cases and half a million deaths worldwide are estimated to be caused by Group A Streptococcus. ScpA (or C5a peptidase) is a well characterised member of the cell enveleope protease family, which possess a S8 subtilisin-like catalytic domain and a shared multi-domain architecture. ScpA cleaves complement factors C5a and C3a, impairing the function of these critical anaphylatoxins and disrupts complement-mediated innate immunity. Although the of high resolution of struct...
Source: Biochimica et Biophysica Acta - August 10, 2023 Category: Biochemistry Authors: Sophie McKenna Frances Aylward Xeni Miliara Rikin J Lau Camilla Berg Huemer Sean P Giblin Kristin K Huse Mingyang Liang Lucy Reeves Max Pearson Yingqi Xu Sarah L Rouse James E Pease Shiranee Sriskandan Todd F Kagawa Jakki Cooney Stephen Matthews Source Type: research
The protease associated (PA) domain in ScpA from Streptococcus pyogenes plays a role in substrate recruitment
Biochim Biophys Acta Proteins Proteom. 2023 Aug 8:140946. doi: 10.1016/j.bbapap.2023.140946. Online ahead of print.ABSTRACTAnnually, over 18 million disease cases and half a million deaths worldwide are estimated to be caused by Group A Streptococcus. ScpA (or C5a peptidase) is a well characterised member of the cell enveleope protease family, which possess a S8 subtilisin-like catalytic domain and a shared multi-domain architecture. ScpA cleaves complement factors C5a and C3a, impairing the function of these critical anaphylatoxins and disrupts complement-mediated innate immunity. Although the of high resolution of struct...
Source: Biochimica et Biophysica Acta - August 10, 2023 Category: Biochemistry Authors: Sophie McKenna Frances Aylward Xeni Miliara Rikin J Lau Camilla Berg Huemer Sean P Giblin Kristin K Huse Mingyang Liang Lucy Reeves Max Pearson Yingqi Xu Sarah L Rouse James E Pease Shiranee Sriskandan Todd F Kagawa Jakki Cooney Stephen Matthews Source Type: research
Severe problem of macrolides resistance to common pathogens in China
With the widespread use of macrolide antibiotics in China, common pathogens causing children’s infections, such as Streptococcus pneumoniae, Streptococcus (including Group A streptococcus, Group B streptococcus), Staphylococcus aureus, Bordetella pertussis, and Mycoplasma pneumoniae, have shown varying degrees of drug resistance. In order to provide such problem and related evidence for rational use of antibiotics in clinic, we reviewed the drug resistance of common bacteria to macrolides in children recent 20 years. (Source: Frontiers in cellular and infection microbiology)
Source: Frontiers in cellular and infection microbiology - August 10, 2023 Category: Microbiology Source Type: research
Group A Streptococcus cation diffusion facilitator proteins contribute to immune evasion by regulating intracellular metal concentrations
Biochem Biophys Res Commun. 2023 Jul 24;676:141-148. doi: 10.1016/j.bbrc.2023.07.052. Online ahead of print.ABSTRACTCation diffusion facilitators (CDFs) are a large family of divalent metal transporters with broad specificities that contribute to intracellular metal homeostasis and toxicity in bacterial pathogens. Streptococcus pyogenes (Group A Streptococcus [GAS]) expresses two homologous CDF efflux transporters, MntE and CzcD, which selectively transport Mn and Zn, respectively. We discovered that the MntE- and CzcD-deficient strains exhibited a marked decrease in the viability of macrophage-differentiated THP-1 cells a...
Source: Biochemical and Biophysical Research communications - July 29, 2023 Category: Biochemistry Authors: Chihiro Aikawa Akihide Shimizu Makoto Nakakido Kazunori Murase Takashi Nozawa Kouhei Tsumoto Ichiro Nakagawa Source Type: research
Group A Streptococcus cation diffusion facilitator proteins contribute to immune evasion by regulating intracellular metal concentrations
Biochem Biophys Res Commun. 2023 Jul 24;676:141-148. doi: 10.1016/j.bbrc.2023.07.052. Online ahead of print.ABSTRACTCation diffusion facilitators (CDFs) are a large family of divalent metal transporters with broad specificities that contribute to intracellular metal homeostasis and toxicity in bacterial pathogens. Streptococcus pyogenes (Group A Streptococcus [GAS]) expresses two homologous CDF efflux transporters, MntE and CzcD, which selectively transport Mn and Zn, respectively. We discovered that the MntE- and CzcD-deficient strains exhibited a marked decrease in the viability of macrophage-differentiated THP-1 cells a...
Source: Biochemical and Biophysical Research communications - July 29, 2023 Category: Biochemistry Authors: Chihiro Aikawa Akihide Shimizu Makoto Nakakido Kazunori Murase Takashi Nozawa Kouhei Tsumoto Ichiro Nakagawa Source Type: research
Group A Streptococcus Meningitis in Adults, Denmark
We report a 21-fold increase in group A Streptococcus meningitis in adults in Denmark during October 13, 2022-April 12, 2023, concurrent with an outbreak of invasive streptococcal disease. We describe clinical characteristics of the outbreak cases and prognosis for patients in comparison to those for previous sporadic cases.PMID:37478289 | DOI:10.3201/eid2909.230627 (Source: Emerging Infectious Diseases)
Source: Emerging Infectious Diseases - July 21, 2023 Category: Infectious Diseases Authors: Henrik Nielsen Merete Storgaard Jannik Helweg-Larsen Lykke Larsen Micha P G Jepsen Birgitte R Hansen Lothar Wiese Jacob Bodilsen Source Type: research
Group A Streptococcus Meningitis in Adults, Denmark
We report a 21-fold increase in group A Streptococcus meningitis in adults in Denmark during October 13, 2022-April 12, 2023, concurrent with an outbreak of invasive streptococcal disease. We describe clinical characteristics of the outbreak cases and prognosis for patients in comparison to those for previous sporadic cases.PMID:37478289 | DOI:10.3201/eid2909.230627 (Source: Emerging Infectious Diseases)
Source: Emerging Infectious Diseases - July 21, 2023 Category: Infectious Diseases Authors: Henrik Nielsen Merete Storgaard Jannik Helweg-Larsen Lykke Larsen Micha P G Jepsen Birgitte R Hansen Lothar Wiese Jacob Bodilsen Source Type: research
Group A Streptococcus Meningitis in Adults, Denmark
We report a 21-fold increase in group A Streptococcus meningitis in adults in Denmark during October 13, 2022-April 12, 2023, concurrent with an outbreak of invasive streptococcal disease. We describe clinical characteristics of the outbreak cases and prognosis for patients in comparison to those for previous sporadic cases.PMID:37478289 | DOI:10.3201/eid2909.230627 (Source: Emerging Infectious Diseases)
Source: Emerging Infectious Diseases - July 21, 2023 Category: Infectious Diseases Authors: Henrik Nielsen Merete Storgaard Jannik Helweg-Larsen Lykke Larsen Micha P G Jepsen Birgitte R Hansen Lothar Wiese Jacob Bodilsen Source Type: research
Group A Streptococcus Meningitis in Adults, Denmark
H. Nielsen et al. (Source: Emerging Infectious Diseases Journal)
Source: Emerging Infectious Diseases Journal - July 21, 2023 Category: Infectious Diseases Source Type: research
Invasive Group A streptococcal infections: are we facing a new outbreak? A case series with the experience of a single tertiary center
ConclusionsAccurate differential diagnosis and early treatment both could help to reduce the transmission of GAS and consequently the risk of severe iGAS. These cases confirmed the need for close monitoring and appropriate notification, in order to verify their actual increased incidence. (Source: Italian Journal of Pediatrics)
Source: Italian Journal of Pediatrics - July 19, 2023 Category: Pediatrics Source Type: research
