A New Rapid and Cost-Effective Method for Detection of Phages, ICEs and Virulence Factors Encoded by Streptococcus pyogenes

Streptococcus pyogenes (group A Streptococcus, GAS) is a human pathogen that causes diseases of various intensity, from mild strep throat to life threatening invasive infections and postinfectional sequelae. S. pyogenes encodes multiple, often phage encoded, virulence factors and their presence is related to severity of the disease. Acquisition of mobile genetic elements, carrying virulence factors, as phages or ICEs (integrative and cojugative elements) has been shown previously to promote selection of virulent clones. We designed the system of eight low volume multi- and one singleplex PCR reactions to detect genes encoding twenty virulence factors (spd3, sdc, sdaB, sdaD, speB, spyCEP, scpA, mac, sic, speL, K, M, C, I, A, H, G, J, smeZ and ssa) and twenty one phage and ICE integration sites described so far for S. pyogenes. Classification of strains based on the phage and virulence factors absence or presence, correlates with PFGE MLST and emm typing results. We developed a novel, fast and cost effective system that can be used to detect GAS virulence factors. Moreover, this system may become an alternative and effective system to differentiate between GAS strains.

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Distribution of emm type and antibiotic susceptibility of group A streptococci causing invasive and noninvasive disease

Journal of Medical Microbiology ◽

10.1099/jmm.0.2008/002642-0 ◽

2008 ◽

Vol 57 (11) ◽

pp. 1383-1388 ◽

Cited By ~ 43

Author(s):

Takeaki Wajima ◽

Somay Y. Murayama ◽

Katsuhiko Sunaoshi ◽

Eiichi Nakayama ◽

Keisuke Sunakawa ◽

...

Keyword(s):

Streptococcus Pyogenes ◽

Macrolide Antibiotic ◽

Group A Streptococcus ◽

Acute Otitis Media ◽

Toxic Shock ◽

Medical Institutions ◽

Invasive Infections ◽

Group A ◽

Resistant Strains ◽

Emm Type

To determine the prevalence of macrolide antibiotic and levofloxacin resistance in infections with Streptococcus pyogenes (group A streptococcus or GAS), strains were collected from 45 medical institutions in various parts of Japan between October 2003 and September 2006. Four hundred and eighty-two strains from patients with GAS infections were characterized genetically. Strains were classified into four groups according to the type of infection: invasive infections (n=74) including sepsis, cellulitis and toxic-shock-like syndrome; acute otitis media (AOM; n=23); abscess (n=53); and pharyngotonsillitis (n=332). Among all strains, 32 emm types were identified; emm1 was significantly more common in invasive infections (39.2 %) and AOM (43.5 %) than in abscesses (3.8 %) or pharyngotonsillitis (10.2 %). emm12 and emm4 each accounted for 23.5 % of pharyngotonsillitis cases. Susceptibility of GAS strains to eight β-lactam agents was excellent, with MICs of 0.0005–0.063 μg ml−1. Macrolide-resistant strains accounted for 16.2 % of all strains, while the percentages of strains possessing the resistance genes erm(A), erm(B) and mef(A) were 2.5 %, 6.2 % and 7.5 %, respectively. Although no strains with high resistance to levofloxacin were found, strains with an MIC of 2–4 μg ml−1 (17.4 %) had amino acid substitutions at either Ser-79 or Asp-83 in ParC. These levofloxacin-intermediately resistant strains included 16 emm types, but macrolide-resistant strains were more likely than others to represent certain emm types.

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Streptococcus pyogenes evades adaptive immunity through specific IgG glycan hydrolysis

Journal of Experimental Medicine ◽

10.1084/jem.20190293 ◽

2019 ◽

Vol 216 (7) ◽

pp. 1615-1629 ◽

Cited By ~ 2

Author(s):

Andreas Naegeli ◽

Eleni Bratanis ◽

Christofer Karlsson ◽

Oonagh Shannon ◽

Raja Kalluru ◽

...

Keyword(s):

Streptococcus Pyogenes ◽

Vaccine Development ◽

Group A Streptococcus ◽

Invasive Infection ◽

Invasive Infections ◽

Life Threatening ◽

Group A ◽

Specific Igg

Streptococcus pyogenes (Group A streptococcus; GAS) is a human pathogen causing diseases from uncomplicated tonsillitis to life-threatening invasive infections. GAS secretes EndoS, an endoglycosidase that specifically cleaves the conserved N-glycan on IgG antibodies. In vitro, removal of this glycan impairs IgG effector functions, but its relevance to GAS infection in vivo is unclear. Using targeted mass spectrometry, we characterized the effects of EndoS on host IgG glycosylation during the course of infections in humans. Substantial IgG glycan hydrolysis occurred at the site of infection and systemically in the severe cases. We demonstrated decreased resistance to phagocytic killing of GAS lacking EndoS in vitro and decreased virulence in a mouse model of invasive infection. This is the first described example of specific bacterial IgG glycan hydrolysis during infection and thereby verifies the hypothesis that EndoS modifies antibodies in vivo. This mechanisms of immune evasion could have implications for treatment of severe GAS infections and for future efforts at vaccine development.

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Virulence factors of Streptococcus pyogenes strains from women in peri-labor with invasive infections

European Journal of Clinical Microbiology & Infectious Diseases ◽

10.1007/s10096-016-2593-0 ◽

2016 ◽

Vol 35 (5) ◽

pp. 747-754 ◽

Cited By ~ 8

Author(s):

E. Golińska ◽

M. van der Linden ◽

G. Więcek ◽

D. Mikołajczyk ◽

A. Machul ◽

...

Keyword(s):

Virulence Factors ◽

Streptococcus Pyogenes ◽

Invasive Infections

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Serine/Threonine Protein Kinase Stk Is Required for Virulence, Stress Response, and Penicillin Tolerance in Streptococcus pyogenes

Infection and Immunity ◽

10.1128/iai.05360-11 ◽

2011 ◽

Vol 79 (10) ◽

pp. 4201-4209 ◽

Cited By ~ 32

Author(s):

Julia Bugrysheva ◽

Barbara J. Froehlich ◽

Jeffrey A. Freiberg ◽

June R. Scott

Keyword(s):

Streptococcus Pyogenes ◽

Fatty Acid Biosynthesis ◽

Group A Streptococcus ◽

Acid Biosynthesis ◽

Regulation Of Expression ◽

Content Type ◽

Reverse Transcription Pcr ◽

Genes Encoding ◽

Group A

ABSTRACTGenes encoding one or more Ser/Thr protein kinases have been identified recently in many bacteria, including one (stk) in the human pathogenStreptococcus pyogenes(group A streptococcus [GAS]). We report that in GAS,stkis required to produce disease in a murine myositis model of infection. Using microarray and quantitative reverse transcription-PCR (qRT-PCR) studies, we found that Stk activates genes for virulence factors, osmoregulation, metabolism of α-glucans, and fatty acid biosynthesis, as well as genes affecting cell wall synthesis. Confirming these transcription studies, we determined that thestkdeletion mutant is more sensitive to osmotic stress and to penicillin than the wild type. We discuss several possible Stk phosphorylation targets that might explain Stk regulation of expression of specific operons and the possible role of Stk in resuscitation from quiescence.

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Streptococcus pyogenes (“Group A Streptococcus”), a Highly Adapted Human Pathogen—Potential Implications of Its Virulence Regulation for Epidemiology and Disease Management

Pathogens ◽

10.3390/pathogens10060776 ◽

2021 ◽

Vol 10 (6) ◽

pp. 776

Author(s):

Nikolai Siemens ◽

Rudolf Lütticken

Keyword(s):

Virulence Factors ◽

Streptococcus Pyogenes ◽

Group A Streptococcus ◽

Human Pathogen ◽

Virulence Regulation ◽

Regulatory Systems ◽

Global Epidemiology ◽

Group A ◽

Prevention Methods ◽

Streptococcus A

Streptococcus pyogenes (group A streptococci; GAS) is an exclusively human pathogen. It causes a variety of suppurative and non-suppurative diseases in people of all ages worldwide. Not all can be successfully treated with antibiotics. A licensed vaccine, in spite of its global importance, is not yet available. GAS express an arsenal of virulence factors responsible for pathological immune reactions. The transcription of all these virulence factors is under the control of three types of virulence-related regulators: (i) two-component systems (TCS), (ii) stand-alone regulators, and (iii) non-coding RNAs. This review summarizes major TCS and stand-alone transcriptional regulatory systems, which are directly associated with virulence control. It is suggested that this treasure of knowledge on the genetics of virulence regulation should be better harnessed for new therapies and prevention methods for GAS infections, thereby changing its global epidemiology for the better.

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Analysis of the Deviation in a Low-Cost System for Stepless Digital Control of Conventional Lathe Spindle Speeds

Applied Sciences ◽

10.3390/app9010012 ◽

2018 ◽

Vol 9 (1) ◽

pp. 12 ◽

Cited By ~ 2

Author(s):

Tadeusz Mikolajczyk ◽

Tomasz Paczkowski ◽

Danil Yurievich Pimenov ◽

Mozammel Mia ◽

Karali Patra ◽

...

Keyword(s):

Digital Control ◽

Low Cost ◽

Cutting Speed ◽

Cost Effective ◽

Spindle Speed ◽

Automated Control ◽

Electric Motor Drives ◽

Multi Stage ◽

Cost Effective Method ◽

Effective System

A conventional manual lathe electric motor drives the multi-stage gearbox transmitting torque to the spindle so that the workpiece makes contact with the machine tool at a given speed. The cutting speed is proportional to both the diameter of the workpiece and the spindle speed, however, the increments in spindle speed are limited. Manual lathe machines cannot be regulated at the optimum cutting speeds for all diameters. An innovative modernization of the main driveline of a TSB16 manual lathe is proposed in this paper, allowing for a cost-effective system for digital control of spindle speeds using an inverter. The inverter is controlled using an 8-bit AO (analog output) converter with special software developed with Visual Basic. The results of the analysis and various test runs with this new system for automated control of spindle rotation, showed that the required cutting speed can be achieved for any workpiece diameter. The deviation of cutting-speed of the upgraded system for any turning diameter is greatly reduced in comparison with the deviation of cutting-speed of a manual lathe. Finally, tests on this versatile system demonstrated a cost-effective method for modernizing the drive system of conventional lathe machines.

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Playing With Fire: Proinflammatory Virulence Mechanisms of Group A Streptococcus

Frontiers in Cellular and Infection Microbiology ◽

10.3389/fcimb.2021.704099 ◽

2021 ◽

Vol 11 ◽

Author(s):

Shyra Wilde ◽

Anders F. Johnson ◽

Christopher N. LaRock

Keyword(s):

Virulence Factors ◽

Group A Streptococcus ◽

Severe Disease ◽

Fatal Outcome ◽

Toxic Shock ◽

Autoreactive Antibodies ◽

Invasive Infections ◽

Group A ◽

Disease Understanding

Group A Streptococcus is an obligate human pathogen that is a major cause of infectious morbidity and mortality. It has a natural tropism for the oropharynx and skin, where it causes infections with excessive inflammation due to its expression of proinflammatory toxins and other virulence factors. Inflammation directly contributes to the severity of invasive infections, toxic shock syndrome, and the induction of severe post-infection autoimmune disease caused by autoreactive antibodies. This review discusses what is known about how the virulence factors of Group A Streptococcus induce inflammation and how this inflammation can promote disease. Understanding of streptococcal pathogenesis and the role of hyper-immune activation during infection may provide new therapeutic targets to treat the often-fatal outcome of severe disease.

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Antibiotic Treatment, Mechanisms for Failure, and Adjunctive Therapies for Infections by Group A Streptococcus

Frontiers in Microbiology ◽

10.3389/fmicb.2021.760255 ◽

2021 ◽

Vol 12 ◽

Author(s):

Anders F. Johnson ◽

Christopher N. LaRock

Keyword(s):

Streptococcus Pyogenes ◽

Disease Burden ◽

Group A Streptococcus ◽

Human Pathogen ◽

Invasive Infections ◽

Group A ◽

Severe Infections ◽

Treatment Mechanisms ◽

Antibiotic Failure ◽

Global Disease Burden

Group A Streptococcus (GAS; Streptococcus pyogenes) is a nearly ubiquitous human pathogen responsible for a significant global disease burden. No vaccine exists, so antibiotics are essential for effective treatment. Despite a lower incidence of antimicrobial resistance than many pathogens, GAS is still a top 10 cause of death due to infections worldwide. The morbidity and mortality are primarily a consequence of the immune sequelae and invasive infections that are difficult to treat with antibiotics. GAS has remained susceptible to penicillin and other β-lactams, despite their widespread use for 80 years. However, the failure of treatment for invasive infections with penicillin has been consistently reported since the introduction of antibiotics, and strains with reduced susceptibility to β-lactams have emerged. Furthermore, isolates responsible for outbreaks of severe infections are increasingly resistant to other antibiotics of choice, such as clindamycin and macrolides. This review focuses on the challenges in the treatment of GAS infection, the mechanisms that contribute to antibiotic failure, and adjunctive therapeutics. Further understanding of these processes will be necessary for improving the treatment of high-risk GAS infections and surveillance for non-susceptible or resistant isolates. These insights will also help guide treatments against other leading pathogens for which conventional antibiotic strategies are increasingly failing.

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RocA Has Serotype-Specific Gene Regulatory and Pathogenesis Activities in Serotype M28 Group A Streptococcus

Infection and Immunity ◽

10.1128/iai.00467-18 ◽

2018 ◽

Vol 86 (11) ◽

Cited By ~ 10

Author(s):

Paul E. Bernard ◽

Priyanka Kachroo ◽

Luchang Zhu ◽

Stephen B. Beres ◽

Jesus M. Eraso ◽

...

Keyword(s):

Mutant Strain ◽

Virulence Factors ◽

Molecular Mechanisms ◽

Group A Streptococcus ◽

Specific Gene ◽

Necrotizing Myositis ◽

Invasive Infections ◽

Group A ◽

Transcription Regulators

ABSTRACTSerotype M28 group A streptococcus (GAS) is a common cause of infections such as pharyngitis (“strep throat”) and necrotizing fasciitis (“flesh-eating” disease). Relatively little is known about the molecular mechanisms underpinning M28 GAS pathogenesis. Whole-genome sequencing studies of M28 GAS strains recovered from patients with invasive infections found an unexpectedly high number of missense (amino acid-changing) and nonsense (protein-truncating) polymorphisms inrocA(regulatorofCov), leading us to hypothesize that altered RocA activity contributes to M28 GAS molecular pathogenesis. To test this hypothesis, an isogenicrocAdeletion mutant strain was created. Transcriptome sequencing (RNA-seq) analysis revealed that RocA inactivation significantly alters the level of transcripts for 427 and 323 genes at mid-exponential and early stationary growth phases, respectively, including genes for 41 transcription regulators and 21 virulence factors. In contrast, RocA transcriptomes from other GAS M protein serotypes are much smaller and include fewer transcription regulators. TherocAmutant strain had significantly increased secreted activity of multiple virulence factors and grew to significantly higher colony counts under acid stressin vitro. RocA inactivation also significantly increased GAS virulence in a mouse model of necrotizing myositis. Our results demonstrate that RocA is an important regulator of transcription regulators and virulence factors in M28 GAS and raise the possibility that naturally occurring polymorphisms inrocAin some fashion contribute to human invasive infections caused by M28 GAS strains.

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