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Kono M, Sakatani H, Kinoshita T, Sadakata H, Miyazaki S, Sano T, Hotomi M. Bactericidal effect of lascufloxacin on HEp-2 cell-internalized group A Streptococcus. J Infect Chemother 2023; 29:401-406. [PMID: 36681190 DOI: 10.1016/j.jiac.2023.01.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Revised: 12/29/2022] [Accepted: 01/17/2023] [Indexed: 01/20/2023]
Abstract
INTRODUCTION Although amoxicillin (AMPC) is recommended as first-line therapy for acute pharyngotonsillitis caused by group A streptococci (GAS), it often fails to eradicate infections. Internalization and subsequent intracellular survival of GAS are considered major mechanisms for penicillin therapeutic failure. It is, therefore, desirable to administer drugs that exert bactericidal effects on extracellular and intracellular GAS. In this study, we aim to investigate the bactericidal effects of lascufloxacin (LSFX) on internalized GAS in HEp-2 cells. MATERIALS AND METHODS The GAS strain M1 and clinical isolate strain #2 were used in this study. Following treatment of GAS-infected human pharyngeal carcinoma epithelial HEp-2 cells with LSFX or AMPC, internalized GAS cells were recovered. The concentrations of LSFX and AMPC were equivalent to 1 × and 2 × MIC for strain M1. Culture medium was used as a control. Time-lapse and fluorescence images of GAS invading HEp-2 cell were obtained. LIVE/DEAD fluorescence staining was used to confirm the viability of internalized GAS. RESULTS LSFX significantly reduced the number of cell-internalized M1 and #2 GAS strains compared to the control (p < 0.01) in a dose-dependent manner. However, AMPC did not reduce this in both strains. Both live and dead intracellular GAS were confirmed in HEp-2 cells exposed to LSFX. In contrast, intracellular GAS survived in HEp-2 cells exposed to AMPC and in the control. CONCLUSION LSFX elicits significant bactericidal effects on cell-internalized GAS, hence it may represent a potent therapeutic option for patients with acute pharyngotonsillitis in whom AMPC treatment has failed.
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Affiliation(s)
- Masamitsu Kono
- Department of Otorhinolaryngology-Head and Neck Surgery, Wakayama Medical University, 811-1 Kimiidera, Wakayama-shi, Wakayama, 641-8510, Japan
| | - Hideki Sakatani
- Department of Otorhinolaryngology-Head and Neck Surgery, Wakayama Medical University, 811-1 Kimiidera, Wakayama-shi, Wakayama, 641-8510, Japan
| | - Tetsuya Kinoshita
- Department of Otorhinolaryngology-Head and Neck Surgery, Wakayama Medical University, 811-1 Kimiidera, Wakayama-shi, Wakayama, 641-8510, Japan
| | - Hisato Sadakata
- TIMELAPSE VISION Inc., PLAZA TORIYAMA 4F, 5-23-11, Honcho, Shiki-shi, Saitama, 353-0004, Japan
| | - Shun Miyazaki
- TIMELAPSE VISION Inc., PLAZA TORIYAMA 4F, 5-23-11, Honcho, Shiki-shi, Saitama, 353-0004, Japan
| | - Takako Sano
- TIMELAPSE VISION Inc., PLAZA TORIYAMA 4F, 5-23-11, Honcho, Shiki-shi, Saitama, 353-0004, Japan
| | - Muneki Hotomi
- Department of Otorhinolaryngology-Head and Neck Surgery, Wakayama Medical University, 811-1 Kimiidera, Wakayama-shi, Wakayama, 641-8510, Japan.
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Wang B, Cleary PP. Intracellular Invasion by Streptococcus pyogenes: Invasins, Host Receptors, and Relevance to Human Disease. Microbiol Spectr 2019; 7:10.1128/microbiolspec.gpp3-0049-2018. [PMID: 31267891 PMCID: PMC10957197 DOI: 10.1128/microbiolspec.gpp3-0049-2018] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Indexed: 12/23/2022] Open
Abstract
The human oral-nasal mucosa is the primary reservoir for Streptococcus pyogenes infections. Although the most common infection of consequence in temperate climates is pharyngitis, the past 25 years have witnessed a dramatic increase in invasive disease in many regions of the world. Historically, S. pyogenes has been associated with sepsis and fulminate systemic infections, but the mechanism by which these streptococci traverse mucosal or epidermal barriers is not understood. The discovery that S. pyogenes can be internalized by mammalian epithelial cells at high frequencies (1-3) and/or open tight junctions to pass between cells (4) provides potential explanations for changes in epidemiology and the ability of this species to breach such barriers. In this article, the invasins and pathways that S. pyogenes uses to reach the intracellular state are reviewed, and the relationship between intracellular invasion and human disease is discussed.
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Affiliation(s)
- Beinan Wang
- Institute of Microbiology, Chinese Academy of Sciences, Beijing China
| | - P Patrick Cleary
- Department of Microbiology and Immunology, University of Minnesota, Minneapolis, MN
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Jendoubi F, Rohde M, Prinz JC. Intracellular Streptococcal Uptake and Persistence: A Potential Cause of Erysipelas Recurrence. Front Med (Lausanne) 2019; 6:6. [PMID: 30761303 PMCID: PMC6361840 DOI: 10.3389/fmed.2019.00006] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2018] [Accepted: 01/10/2019] [Indexed: 12/21/2022] Open
Abstract
Erysipelas is a severe streptococcal infection of the skin primarily spreading through the lymphatic vessels. Penicillin is the treatment of choice. The most common complication consists in relapses which occur in up to 40% or more of patients despite appropriate antibiotic treatment. They cause lymphatic damage resulting in irreversible lymphedema and ultimately elephantiasis nostras and lead to major health restrictions and high socio-medical costs. Prevention of relapses is an unmet need, because even long-term prophylactic penicillin application does eventually not reduce the risk of recurrence. In this article we assess risk factors and causes of erysipelas recurrence. A systematic literature search for clinical studies addressing potential causes and measures for prevention of erysipelas recurrence was combined with a review of experimental and clinical data assessing the ability and clinical relevance of streptococci for intracellular uptake and persistence. The literature review found that venous insufficiency, lymphedema, and intertrigo from fungal infections are considered to be major risk factors for recurrence of erysipelas but cannot adequately explain the high recurrence rate. As hitherto unrecognized likely cause of erysipelas relapses we identify the ability of streptococci for intracellular uptake into and persistence within epithelial and endothelial cells and macrophages. This creates intracellular streptococcal reservoirs out of reach of penicillins which do not reach sufficient bactericidal intracellular concentrations. Incomplete streptococcal elimination due to intracellular streptococcal persistence has been observed in various deep tissue infections and is considered as cause of relapsing streptococcal pharyngitis despite proper antibiotic treatment. It may also serves as endogenous infectious source of erysipelas relapses. We conclude that the current antibiotic treatment strategies and elimination of conventional risk factors employed in erysipelas management are insufficient to prevent erysipelas recurrence. The reactivation of streptococcal infection from intracellular reservoirs represents a plausible explanation for the frequent occurrence erysipelas relapses. Prevention of erysipelas relapses therefore demands for novel antibiotic strategies capable of eradicating intracellular streptococcal persistence.
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Affiliation(s)
- Fatma Jendoubi
- Department of Dermatology, University Clinics, Ludwig-Maximilian University of Munich, Munich, Germany.,Faculty of Medicine of Tunis, University Tunis El Manar, Tunis, Tunisia
| | - Manfred Rohde
- Central Facility for Microscopy, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Jörg Christoph Prinz
- Department of Dermatology, University Clinics, Ludwig-Maximilian University of Munich, Munich, Germany
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4
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Saito M, Hirose M, Ichinose H, Villanueva SYAM, Yoshida SI. Molecular analysis of Streptococcus pyogenes strains isolated from patients with recurrent pharyngitis after oral amoxicillin treatment. J Med Microbiol 2018; 67:1544-1550. [DOI: 10.1099/jmm.0.000833] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Affiliation(s)
- Mitsumasa Saito
- 1Department of Microbiology, School of Medicine, University of Occupational and Environmental Health, Kita-Kyushu, Japan
- 2Department of Bacteriology, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, Fukuoka 812-8582, Japan
| | - Mizuo Hirose
- 3Hirose Children's Clinic, 8-12 Nakanokouji, Saga, Saga 840-0833, Japan
| | - Hirofumi Ichinose
- 4Section of Clinical Laboratories, Preventive Center for Adult-Disease of Saga Medical Association, 2-15 Shinnaka-machi, Saga, Saga 849-0924, Japan
| | - Sharon Y. A. M. Villanueva
- 2Department of Bacteriology, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, Fukuoka 812-8582, Japan
- 5Department of Medical Microbiology, College of Public Health, University of the Philippines-Manila, Manila, Philippines
| | - Shin-ichi Yoshida
- 2Department of Bacteriology, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, Fukuoka 812-8582, Japan
- †Present address: Professor Emeritus, Kyushu University
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Balaji K, Thenmozhi R, Prajna L, Dhananjeyan G, Pandian SK. Comparative analysis of emm types, superantigen gene profiles and antibiotic resistance genes among Streptococcus pyogenes isolates from ocular infections, pharyngitis and asymptomatic children in south India. INFECTION GENETICS AND EVOLUTION 2013; 19:105-12. [PMID: 23851012 DOI: 10.1016/j.meegid.2013.06.018] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2013] [Revised: 06/11/2013] [Accepted: 06/15/2013] [Indexed: 10/26/2022]
Abstract
Group A Streptococcus (Streptococcus pyogenes) is responsible for a wide array of infections and incidence is high in developing countries like India. Although distribution of emm types of S. pyogenes in India has been described, its association with the virulence genes and ocular isolates is less concentrated. In the present study emm type surveillance as well as its association with toxin gene profile was analyzed. Ocular infected cases such as lacrimal abscess, corneal ulcers, mucocoele showed the presence of 20 S. pyogenes isolates. For noninvasive isolates, we screened 370 pharyngitis cases and 400 asymptomatic school children and recovered 33 pharyngitis and 14 carrier isolates respectively. 14 Emm type distributions were observed in ocular isolates, 11 emm types each in pharyngitis and asymptomatic carrier isolates. The two dominant emm types, emm49 and emm63 were accounted for 33% of the total S. pyogenes isolates. Among ocular isolates, slo, smeZ, speB and speG were found in >50% of isolates, in pharyngitis smeZ (48%), speB (45%) and speG (42%) genes were found to be prevalent. Alarmingly, carrier isolates showed more prevalence to virulence genes than the ocular and pharyngitis isolates with speF (79%), speB, speG (64%), slo and sil (64%). Among the three groups, pharyngitis isolates harbored more prtF1 (33%) and prtF2 (94%) than the asymptomatic carriers (28% and 71%) and the ocular isolates (45% and 40%). 450bp Size band in prtF1 and 350bp size band in prtF2 showed dominance. Among the three groups tested, the distribution of ermB and mefA was high in pharyngitis isolates (30%) where 10 isolates showed the presence of both genes. None of the isolates showed the presence of ermA and tetO genes. Dendrogram generated based on the virulence and antibiotic resistance gene profiles revealed that except one cluster, all other clusters showed some correlation with ocular, pharyngitis and asymptomatic carrier isolates, irrespective of their emm types.
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Affiliation(s)
- Kannan Balaji
- Department of Biotechnology, Alagappa University, Karaikudi, Tamil Nadu, India
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6
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Hotomi M, Billal DS, Togawa A, Ikeda Y, Takei S, Kono M, Ogami M, Ubukata K, Sugita R, Fujihara K, Yamanaka N. Distribution of fibronectin-binding protein genes (prtF1 and prtF2) and streptococcal pyrogenic exotoxin genes (spe) among Streptococcus pyogenes in Japan. J Infect Chemother 2009; 15:367-73. [PMID: 20012726 DOI: 10.1007/s10156-009-0724-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2009] [Accepted: 08/06/2009] [Indexed: 10/20/2022]
Abstract
Two hundred and seventy-two strains of Streptococcus pyogenes isolated from patients with invasive and noninvasive infections in Japan were evaluated for the prevalence of fibronectin-binding protein genes (prtF1 and prtF2). The possible associations of the genes with streptococcal pyrogenic exotoxin genes, macrolide resistance genes, and emm types were also evaluated. Overall, about 50% of S. pyogenes isolates carried fibronectin-binding protein genes. The prevalence of the prtF1 gene was significantly higher among isolates from noninvasive infections (71.4%) than among isolates from invasive infections (30.8%; P = 0.0037). Strains possessing both the prtF1 and prtF2 genes were more likely to be isolates from noninvasive infections than isolates from invasive infections (50.6% vs 15.4%; P = 0.019). S. pyogenes isolates with streptococcus pyrogenic exotoxin genes (speA and speZ) were more common among isolates without fibronectin-binding protein genes. The speC gene was more frequently identified among isolates with fibronectin-binding protein genes (P = 0.05). Strains belonging to emm75 or emm12 types more frequently harbored macrolide resistance genes than other emm types (P = 0.0094 and P = 0.043, respectively). Strains carrying more than one repeat at the RD2 region of the prtF1 gene and the FBRD region of the prtF2 gene were more prevalent among strains with macrolide resistance genes than among strains negative for macrolide resistance genes. These genes (i.e., the prtF1, prtF2, and spe genes) may enable host-bacteria interaction, and internalization in the host cell, but may not enable infection complications such as invasive diseases.
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Affiliation(s)
- Muneki Hotomi
- Department of Otolaryngology-Head and Neck Surgery, Wakayama Medical University, 811-1 Kimiidera, Wakayama, 641-8509, Japan
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7
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Skoulakis C, Tigiroglou E, Gkarelis K, Klapsa D, Damani A, Papadakis C, Petinaki E. Level of Streptococcus pyogenes in patients with recurrent tonsillitis and tonsillar hypertrophy. ACTA ACUST UNITED AC 2009; 40:899-903. [PMID: 18785068 DOI: 10.1080/00365540802419048] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Recurrent tonsillitis is 1 of the common human infectious diseases worldwide, but, to date, its pathogenesis remains unclear. Although Streptococcus pyogenes (GAS) is involved in recurrent bouts of acute tonsillitis, conventional cultures usually fail to isolate it. The purpose of this study was to clarify whether the deep tonsillar tissues of patients with recurrent tonsillitis might harbour GAS, resulting in reinfections. Deep tonsillar tissues obtained from 285 patients with recurrent tonsillitis and 172 patients with tonsillar hypertrophy, who had undergone tonsillectomy, were examined for the presence of GAS, using conventional and molecular methods. Cultures from all patients were negative for GAS. GAS DNA was found in the deep tonsillar tissues of 57 out of 285 patients with recurrences (20%), and GAS RNA, indicating the viability of GAS, was detected in 47 of them (82%). On the other hand, Haemophilus influenzae DNA was found in 15% and 16% of patients with recurrences and hypertrophy, respectively; but no Haemophilus influenzae RNA presence was detected. The low level of presence of GAS in patients with recurrent tonsillitis indicates that other unknown factors may be responsible for the recurrences.
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Affiliation(s)
- Ch Skoulakis
- ENT Department, General Hospital of Volos, Greece
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8
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Hyland KA, Wang B, Cleary PP. Protein F1 and Streptococcus pyogenes resistance to phagocytosis. Infect Immun 2007; 75:3188-91. [PMID: 17371855 PMCID: PMC1932906 DOI: 10.1128/iai.01745-06] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2006] [Revised: 01/24/2007] [Accepted: 03/13/2007] [Indexed: 11/20/2022] Open
Abstract
Streptococcus pyogenes is a major cause of pharyngitis in humans and encodes several fibronectin-binding proteins. M protein and protein F1 (PrtF1/SfbI) are differentially regulated by CO(2) and O(2), respectively, and both mediate the invasion of epithelial cells. This study examined whether PrtF1/SfbI shares other properties with M protein. Expression of the PrtF1/SfbI protein by an M-negative mutant conferred resistance to phagocytosis and partial inhibition of C3 deposition on the S. pyogenes surface.
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Affiliation(s)
- Kendra A Hyland
- Department of Microbiology, University of Minnesota Medical School, MMC196, 420 Delaware Street S.E., Minneapolis, MN 55455, USA.
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9
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Tart AH, Walker MJ, Musser JM. New understanding of the group A Streptococcus pathogenesis cycle. Trends Microbiol 2007; 15:318-25. [PMID: 17524649 DOI: 10.1016/j.tim.2007.05.001] [Citation(s) in RCA: 86] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2007] [Revised: 03/26/2007] [Accepted: 05/09/2007] [Indexed: 10/23/2022]
Abstract
Group A Streptococcus (GAS) has long been recognized as a human pathogen causing an exceptionally broad range of infections. Despite intense research, however, the molecular mechanisms of GAS disease remain unclear. Recently, many important discoveries have been made that shed light on GAS pathogenesis and open exciting avenues for future research. Advances in genome sequencing, microarray technology and proteomic analysis, in combination with the development of more suitable animal models, have markedly increased our knowledge of the mechanisms underlying GAS pathogenesis. The information gained from these studies will translate into improved diagnostics and new targets for therapeutic drugs and vaccines.
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Affiliation(s)
- Anne H Tart
- Center for Molecular and Translational Human Infectious Diseases Research, The Methodist Hospital Research Institute, and Department of Pathology, The Methodist Hospital, 6565 Fannin Street B490, Houston, TX 77030, USA
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Baldassarri L, Creti R, Imperi M, Recchia S, Pataracchia M, Orefici G. Detection of genes encoding internalization-associated proteins in Streptococcus pyogenes isolates from patients with invasive diseases and asymptomatic carriers. J Clin Microbiol 2007; 45:1284-7. [PMID: 17287324 PMCID: PMC1865825 DOI: 10.1128/jcm.02119-06] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A total of 161 Streptococcus pyogenes isolates from patients with invasive infections or from asymptomatic carriers were examined for genes (prtF1, prtF2, and fba) coding for fibronectin-binding proteins to evaluate their involvement in the pathogenesis of different streptococcal manifestations. We found no significant differences in the presence of these three genes between the two groups. Overall, the prtF2 gene was present in similar percentages among strains from both sources (61% versus 63%). Strains carrying the gene fba were slightly more common among those isolated from asymptomatic carriers (72.6% versus 65%). Also, the prtF1 gene was present in a higher, but not significant, percentage among strains from throat swabs than among isolates from invasive infections (75% versus 64.9%). However, this more detailed characterization of the genes encoding fibronectin-binding proteins allowed us to identify a strong association of genes of the erm class, coding for macrolide resistance, with prtF1 and prtF2 rather than with prtF1 alone. Since macrolide resistance was significantly associated with throat swab isolates, it may be hypothesized that proteins coded by prtF1 and prtF2 genes may be synergic in providing support for cell invasion and/or colonizing or persistence efficiency.
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Affiliation(s)
- Lucilla Baldassarri
- Dipartimento di Malattie Infettive, Parassitarie ed Immunomediate, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161 Rome, Italy.
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Variations in the distribution of genes encoding virulence and extracellular proteins in group A streptococcus are largely restricted to 11 genomic loci. Microbes Infect 2006; 9:259-70. [PMID: 17307378 DOI: 10.1016/j.micinf.2006.11.014] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2006] [Revised: 10/05/2006] [Accepted: 11/20/2006] [Indexed: 12/14/2022]
Abstract
Group A streptococcus (GAS) is a human pathogen associated with a wide range of human diseases that vary in symptoms and clinical severity. In this report we describe the use of a targeted low density array representing genes encoding classical virulence factors, purported virulence factors and other extracellular proteins to examine differences in the genetic profiles of 68 clinical GAS isolates. Of the 226 genes on the array (encoding 217 virulence factors or putative extracellular proteins and nine positive control house-keeping proteins) 62 had distributions that were statistically associated with specific GAS M-types. While 32 of these genes were bacteriophage related, the remaining 30 have not previously been described as bacteriophage associated. We show that these 'non-bacteriophage related' genes are found in 11 loci located in five greater chromosomal regions, often near classical GAS virulence factors, and often accompanied by genes associated with mobile genetic elements (MGEs). Many of these loci also demonstrated genetic variation within strains of the same M-type, suggesting these regions to be recombinatorial and mutational hotspots. Evidence for acquisition of genes from other species is also apparent in these loci. Our data suggests that imprecise recombination events involving MGEs not only result in acquisition of new genes, but can also result in deletion of flanking chromosomal genes. Thus MGE related events would appear to be the major contributor to variation of discrete virulence loci, which could account for the disease causing propensity of individual strains. We believe that profiling of the 11 loci could be a meaningful tool in epidemiological GAS typing studies.
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Podbielski A. Flexible architecture of the Streptococcus pyogenes FCT genome region: finally the clue for understanding purulent skin diseases and long-term persistence? J Bacteriol 2006; 189:1181-4. [PMID: 17142401 PMCID: PMC1797344 DOI: 10.1128/jb.01748-06] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Affiliation(s)
- Andreas Podbielski
- Department of Medical Microbiology, Virology and Hygiene, University Hospital, Schillingallee 70, D-18057 Rostock, Germany.
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13
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Bianco S, Allice T, Zucca M, Savoia D. Survey of phenotypic and genetic features of streptococcus pyogenes strains isolated in Northwest Italy. Curr Microbiol 2005; 52:33-9. [PMID: 16391999 DOI: 10.1007/s00284-005-0067-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2005] [Accepted: 08/22/2005] [Indexed: 11/29/2022]
Abstract
Streptococcus pyogenes (group A Streptococcus [GAS]) is an important pathogen whose virulence is related to the production of exotoxins and the presence of particular surface components. One hundred eighty-two GAS strains were collected in northwestern Italy between 1994 and 2002 and analyzed for phenotypic characteristics (opacity factor, proteolyic activity, and antimicrobial susceptibility) and by polymerase chain reaction for the presence of genes responsible for the production of exotoxins implicated in pathogenesis speA and speF and of prtF(1) (encoding fibronectin-binding protein F1). All strains were speF positive and 19.2% were speA positive and prtF(1) negative, whereas the prtF(1) gene was identified in 39.5% of the other strains. Of these, approximately half revealed the same pulse-field gel electrophoresis (PFGE) pattern but differed in both speA gene and macrolide resistance.
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Affiliation(s)
- Simona Bianco
- Dipartimento di Scienze Cliniche e Biologiche, Università di Torino, c/o Ospedale S. Luigi Gonzaga, Regione Gonzole, 10043 Orbassano (TO), Italy
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Wood DN, Chaussee MA, Chaussee MS, Buttaro BA. Persistence of Streptococcus pyogenes in stationary-phase cultures. J Bacteriol 2005; 187:3319-28. [PMID: 15866916 PMCID: PMC1111994 DOI: 10.1128/jb.187.10.3319-3328.2005] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
In addition to causing fulminant disease, Streptococcus pyogenes may be asymptomatically carried between recurrent episodes of pharyngitis. To better understand streptococcal carriage, we characterized in vitro long-term stationary-phase survival (>4 weeks) of S. pyogenes. When grown in sugar-limited Todd-Hewitt broth, S. pyogenes cells remained culturable for more than 1 year. Both Todd-Hewitt supplemented with excess glucose and chemically defined medium allowed survival for less than 1 week. After 4 weeks of survival in sugar-limited Todd-Hewitt broth, at least 10(3) CFU per ml remained. When stained with fluorescent live-dead viability stain, there were a number of cells with intact membranes that were nonculturable. Under conditions that did not support persistence, these cells disappeared 2 weeks after loss of culturability. In persistent cultures, these may be cells that are dying during cell turnover. After more than 4 weeks in stationary phase, the culturable cells formed two alternative colony phenotypes: atypical large colonies and microcolonies. Protein expression in two independently isolated microcolony strains, from 14-week cultures, was examined by use of two-dimensional electrophoresis. The proteomes of these two strains exhibited extensive changes compared to the parental strain. While some of these changes were common to the two strains, many of the changes were unique to a single strain. Some of the common changes were in metabolic pathways, suggesting a possible alternate metabolism for the persisters. Overall, these data suggest that under certain in vitro conditions, S. pyogenes cells can persist for greater than 1 year as a dynamic population.
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Affiliation(s)
- Daniel N Wood
- Department of Microbiology and Immunology, Temple University School of Medicine, Philadelphia, Pennsylvania 19140, USA
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15
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Cocuzza CE, Lanzafame A, Sisto F, Broccolo F, Mattina R. Prevalence of the internalization-associated gene prtF1 in a bacterial population of Streptococcus pyogenes isolated from children with acute pharyngotonsillitis before and after antibiotic therapy. Microb Drug Resist 2005; 10:264-8. [PMID: 15383172 DOI: 10.1089/mdr.2004.10.264] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The prevalence of the internalization-associated prtF1 gene was studied in 837 isolates of Streptococcus pyogenes obtained from 713 pediatric patients presenting with acute pharyngotonsillitis before and after antibiotic therapy. Its association with macrolide resistance and with bacteriological treatment failure was determined. The bacterial population isolated from baseline pharyngeal swabs showed an overall prtF1 positivity rate of 33%. A higher prtF1 positivity was found among erythromycin-resistant strains (45%) showing, however, marked differences between the inducible (iMLS), constitutive (cMLS), and efflux pump (M) resistance phenotypes. The prevalence was statistically higher (p < 0.001) in strains belonging to iMLS (84%) and cMLS (67%) phenotypes as compared to the M phenotype (15%). Interestingly, the prevalence of the prtF1 gene was significantly lower (p = 0.04) in strains belonging to M resistance phenotype as compared to erythromycin-susceptible strains (28%). Failed bacterial eradication was demonstrated in 124 patients. The prtF1 positivity rate remained unchanged in strains isolated before and after therapy in patients treated with macrolides (9/54). On the other hand, the positivity rate for the prtF1 gene was significantly higher (p = 0.015) in strains isolated after therapy with beta-lactams (21/70) as compared to baseline isolates (6/70), indicating a differential selection imposed on the organism by these agents. Finally, a high overall eradication rate (88%) of prtF1-positive isolates, belonging to both the erythromycin-susceptible and -resistant phenotypes, was demonstrated following macrolide treatment.
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Affiliation(s)
- C E Cocuzza
- Department of Clinical Medicine, Prevention and Biotechnologies, University of Milano-Bicocca, Monza, Italy.
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Kreikemeyer B, Klenk M, Podbielski A. The intracellular status of Streptococcus pyogenes: role of extracellular matrix-binding proteins and their regulation. Int J Med Microbiol 2004; 294:177-88. [PMID: 15493828 DOI: 10.1016/j.ijmm.2004.06.017] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Streptococcus pyogenes (group A streptococci, GAS) is an important and exclusively human pathogen. Adherence to and internalization into host cells significantly contributes to the pathogenesis of GAS infections. The adherence mechanism is a two-step process in which host extracellular matrix (ECM) proteins act as prime targets. GAS may express more than a dozen different microbial surface components recognizing adhesive matrix molecules (MSCRAMMs) that attach to fibronectin or collagen. One of them, protein F1/SfbI binds fibronectin and mediates adherence of GAS to host cells. Bound fibronectin acts as a bridging molecule towards host cell integrins, which in turn initialize the uptake process that leads to GAS internalization. In their safe intracellular niche GAS can persist protected from antibiotics and host defense, a scenario currently discussed in the context of treatment failure, asymptomatic GAS carriers and recurrent GAS infections. Patients with such low grade infections represent the main GAS reservoir from which the bacteria are spread in the general population. Due to their important function, expression of GAS MSCRAMMs is under control of several "stand alone" transcriptional regulators and two-component signal transduction systems. Several regulator genes are organized together with MSCRAMM genes on one of two potential pathogenicity islands, act together in a growth phase-dependent regulatory network and are expressed in a strain-specific manner. A detailed understanding of these mechanisms is crucial, since interference with MSCRAMM function alone or in conjunction with specific manipulations of regulators is an attractive goal for novel anti-infective strategies.
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Affiliation(s)
- Bernd Kreikemeyer
- Department of Medical Microbiology and Hospital Hygiene, University Hospital Rostock, Schillingallee 70, D-18055 Rostock, Germany.
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17
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Oehmcke S, Podbielski A, Kreikemeyer B. Function of the fibronectin-binding serum opacity factor of Streptococcus pyogenes in adherence to epithelial cells. Infect Immun 2004; 72:4302-8. [PMID: 15213180 PMCID: PMC427420 DOI: 10.1128/iai.72.7.4302-4308.2004] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The serum opacity factor (SOF) of Streptococcus pyogenes is a serotyping tool and pathogenesis factor. Using SOF-coated latex beads in cell adherence assays and antiserum directed against SOF in S. pyogenes-HEp-2 cell adherence inhibition experiments, we demonstrate SOF involvement in the fibronectin-mediated adherence of S. pyogenes to epithelial cells. SOF exclusively targets the 30-kDa N-terminal region of fibronectin. The interaction revealed association and dissociation constants 1 order of magnitude lower than those of other S. pyogenes fibronectin-binding proteins.
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Affiliation(s)
- Sonja Oehmcke
- Department of Medical Microbiology and Hospital Hygiene, University Hospital Rostock, Schillingallee 70, 18055 Rostock, Germany
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18
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Binks M, Sriprakash KS. Characterization of a complement-binding protein, DRS, from strains of Streptococcus pyogenes containing the emm12 and emm55 genes. Infect Immun 2004; 72:3981-6. [PMID: 15213143 PMCID: PMC427425 DOI: 10.1128/iai.72.7.3981-3986.2004] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
An extracellular protein of Streptococcus pyogenes, streptococcal inhibitor of complement (SIC), and its variant, called DRS (distantly related to SIC), are expressed by some S. pyogenes strains. SIC from type 1 (M1) isolates of S. pyogenes interferes with complement-mediated cell lysis, reportedly via its interaction with complement proteins. In this study we demonstrate that S. pyogenes strains carrying emm12 and emm55 (the genes for the M12 and M55 proteins, respectively) express and secrete DRS. This protein, like SIC, binds to the C6 and C7 complement proteins, and competition enzyme-linked immunosorbent assay experiments demonstrate that DRS competes with SIC for C6 and C7 binding. Similarly, SIC competes with DRS for binding to the complement proteins. Despite this, the recombinant DRS preparation showed no significant effect on complement function, as determined by lysis of sensitized sheep erythrocytes. Furthermore, the presence of DRS is not inhibitory to SIC activity.
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Affiliation(s)
- Michael Binks
- Queensland Institute of Medical Research, 300 Herston Road, Herston, Queensland 4006, Australia
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19
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Spinaci C, Magi G, Zampaloni C, Vitali LA, Paoletti C, Catania MR, Prenna M, Ferrante L, Ripa S, Varaldo PE, Facinelli B. Genetic diversity of cell-invasive erythromycin-resistant and -susceptible group A streptococci determined by analysis of the RD2 region of the prtF1 gene. J Clin Microbiol 2004; 42:639-44. [PMID: 14766830 PMCID: PMC344491 DOI: 10.1128/jcm.42.2.639-644.2004] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2003] [Revised: 09/20/2003] [Accepted: 11/13/2003] [Indexed: 11/20/2022] Open
Abstract
The RD2 region of the internalization-associated gene prtF1, which encodes the fibronectin-binding repeat domain type 2 of protein F1, plays a crucial role in the entry of group A streptococci (GAS) into epithelial cells. A molecular study of the variability of the RD2 region was carried out with 77 independent Italian GAS, 66 erythromycin resistant (ER) and 11 erythromycin susceptible (ES), which had previously been investigated for the association between erythromycin resistance and ability to enter human respiratory cells. The amplicons obtained from PCR analysis of the RD2 region were consistent with a number of RD2 repeats ranging from one to five, more frequently four (n = 30), three (n = 27), and one (n = 18). A new method to type cell-invasive GAS (RD2 typing) was developed by combining PCR analysis of the RD2 region and restriction analysis of PCR products with endonucleases HaeIII, DdeI, and HinfI. Overall, 10 RD2 types (a to j) were distinguished (all detected among the 66 ER isolates, four detected among the 11 ES isolates). Comparison and correlation of RD2 typing data with the genotype and phenotype of macrolide resistance and with data from PCR M typing and SmaI macrorestriction analysis allowed us to identify 41 different clones (31 among the 66 ER isolates and 10 among the 11 ES isolates). Three major clones accounted for 40% of the isolates (47% of ER strains). Some ES isolates appeared to be related to ER isolates with identical combinations of RD2 type and emm type. While simultaneous use of different typing methods is essential for a thorough investigation of GAS epidemiology, RD2 typing may be especially helpful in typing cell-invasive GAS.
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Affiliation(s)
- Cinzia Spinaci
- Department of Microbiology and Biomedical Sciences, University of Ancona Medical School, 60131 Ancona, Italy
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20
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Kreikemeyer B, Oehmcke S, Nakata M, Hoffrogge R, Podbielski A. Streptococcus pyogenes fibronectin-binding protein F2: expression profile, binding characteristics, and impact on eukaryotic cell interactions. J Biol Chem 2004; 279:15850-9. [PMID: 14749329 DOI: 10.1074/jbc.m313613200] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Some Streptococcus pyogenes (group A streptococci, GAS) strains have previously been shown to express the fibronectin-binding protein F2 instead of the functionally related but structurally dissimilar protein F1/SfbI. In this study, recombinant N-terminal and C-terminal portions and the two fibronectin-binding domains of protein F2 were used to assess affinity parameters of the interaction with fibronectin and its N-terminal 70-, 30-, and 45-kDa fragments. The association and dissociation equilibrium constants for both binding domains were in the nanomolar range, although the repeat domain of protein F2 exceeded the affinity of the unique domain by up to one order magnitude. Both domains primarily interacted with the 30-kDa fibronectin fragment. Using a prtF2 gene isogenic mutant of a serotype M49 GAS strain that does not harbor the protein F1/SfbI gene, the attachment values of whole bacteria to immobilized fibronectin and to HEp-2 epithelial cells were found to be 6- and 2-fold decreased, respectively. Reduction of prtF2 mutant internalization rates for eukaryotic cells exceeded the reduction of attachment rates, indicating an independent contribution of protein F2 to both processes. The prtF2 transcription and protein F2 expression profiles documented maximum expression at the transition to the stationary phase especially under aerobic growth condition. The protein F2 function as the major fibronectin-binding adhesin in a subset of GAS strains, its expression pattern, and highly specific interaction with fibronectin would be consistent with a status as an indispensable virulence factor for both earlier and later pathogenetic stages of GAS superficial infections.
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Affiliation(s)
- Bernd Kreikemeyer
- Department of Medical Microbiology and Hospital Hygiene, Hospital of the Rostock University, Schillingallee 70, 18057 Rostock, Germany
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21
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Musumeci R, Bue CL, Milazzo I, Nicoletti G, Serra A, Speciale A, Blandino G. Internalization-associated proteins among Streptococcus pyogenes isolated from asymptomatic carriers and children with pharyngitis. Clin Infect Dis 2003; 37:173-9. [PMID: 12856208 DOI: 10.1086/375589] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2002] [Accepted: 03/05/2003] [Indexed: 11/03/2022] Open
Abstract
Sixty-two strains of Streptococcus pyogenes isolated from 30 asymptomatic school children and 32 children with pharyngitis were characterized to analyze the involvement of 2 fibronectin-binding proteins (F/SfbI and PrtF2/PfbpI) in S. pyogenes colonizing asymptomatic carriers and to determine the possible association between these proteins and the genes associated with macrolide resistance. In this study, we demonstrated that the proportion of S. pyogenes strains carrying the pfbpI gene was significantly higher among asymptomatic carriers (80%) than among children with pharyngitis (53%; P<.05). With regard to the proportion of prtF1-positive strains, no significant differences were found between the 2 groups (70% vs. 69%, for asymptomatic carriers and children with pharyngitis, respectively). Another important finding is the significant association between macrolide resistance and protein F/SfbI (P<.001) in both groups. These results suggest that the presence of the pfbpI gene can be linked to the ability of S. pyogenes to persist in the throat of asymptomatic carriers.
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Affiliation(s)
- R Musumeci
- Department of Microbiological and Gynecological Sciences, Section of Microbiology, University of Catania, 95124 Catania, Italy
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22
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Mazón A, Gil-Setas A, Sota de la Gándara LJ, Vindel A, Sáez-Nieto JA. Transmission of Streptococcus pyogenes causing successive infections in a family. Clin Microbiol Infect 2003; 9:554-9. [PMID: 12848734 DOI: 10.1046/j.1469-0691.2003.00567.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The objective of this study was to determine the characteristics of Streptococcus pyogenes isolated during a 10-month period from members of a family with infections and asymptomatic carriage. T-serotyping and pulsed-field gel electrophoresis confirmed that distinct GAS clones were introduced into the family over a short period of time.
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Affiliation(s)
- A Mazón
- Laboratorio de Microbiología, Ambulatorio General Solchaga, Pamplona, Spain
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23
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Podbielski A, Beckert S, Schattke R, Leithäuser F, Lestin F, Gossler B, Kreikemeyer B. Epidemiology and virulence gene expression of intracellular group A streptococci in tonsils of recurrently infected adults. Int J Med Microbiol 2003; 293:179-90. [PMID: 12868654 DOI: 10.1078/1438-4221-00253] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Intracellularly persistent group A streptococci (GAS, Streptococcus pyogenes) have been associated with recurrent tonsillopharyngitis and antibiotic treatment failure. As a supplementation of the published in vitro data, conventional bacteriology and molecular epidemiology was performed on material from 29 adult patients of a German army hospital with anamnestic signs of recurrent tonsillopharyngitis. Pre-surgery tonsil swabs and the surgically removed tonsils were examined with respect to growth of aerobic bacteria in absence and presence of antibiotics with exclusively extracellular activity. Under such antibiotic selection, Staphylococcus aureus and GAS were cultured from specimens of 13 and 3 patients, respectively. In every material GAS-positive by culture methods, the intracellular location of the penicillin-susceptible GAS isolates was confirmed by immunohistologic examination of tonsillar sections using a GAS-specific IgG antibody. The three intracellular GAS isolates were typed by emm gene sequencing and could be associated to types M6 and M49 (two isolates). The bacteria were serially passaged on sheep blood agar, and semiquantitative mRNA analysis from virulence genes was performed using bacteria of the 4th and 25th passage after isolation. An M-type-specific pattern of virulence gene expression and different gene expression levels in relation to the passage number were observed.
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Affiliation(s)
- Andreas Podbielski
- Department of Medical Microbiology and Hospital Hygiene, University Hospital, Rostock, Germany.
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24
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Frick IM, Akesson P, Rasmussen M, Schmidtchen A, Björck L. SIC, a secreted protein of Streptococcus pyogenes that inactivates antibacterial peptides. J Biol Chem 2003; 278:16561-6. [PMID: 12621031 DOI: 10.1074/jbc.m301995200] [Citation(s) in RCA: 136] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Some isolates of the significant human pathogen Streptococcus pyogenes, including virulent strains of the M1 serotype, secrete protein SIC. This molecule, secreted in large quantities, interferes with complement function. As a result of natural selection, SIC shows a high degree of variation. Here we provide a plausible explanation for this variation and the fact that strains of the M1 serotype are the most frequent cause of severe invasive S. pyogenes infections. Thus, protein SIC was found to inactivate human neutrophil alpha-defensin and LL-37, two major antibacterial peptides involved in bacterial clearance. This inactivation protected S. pyogenes against the antibacterial effect of the peptides. Moreover, SIC isolated from S. pyogenes of the M1 serotype was more powerful in this respect than SIC variants from strains of M serotypes 12 and 55, serotypes rarely connected with invasive infections.
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Affiliation(s)
- Inga-Maria Frick
- Department of Cell and Molecular Biology, Lund University, S-221 85 Lund, Sweden.
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25
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Brandt CM, Haase G, Spellerberg B, Holland R, Lütticken R. drs (Distantly related sic) gene polymorphisms among emm12-type Streptococcus pyogenes isolates. J Clin Microbiol 2003; 41:1794-7. [PMID: 12682191 PMCID: PMC153900 DOI: 10.1128/jcm.41.4.1794-1797.2003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Twenty-eight emm12-type Streptococcus pyogenes isolates from patients with invasive and noninvasive infections or from asymptomatic carriers were genetically typed. Sequencing of drs (distantly related sic [streptococcal inhibitor of complement]) genes identified two novel alleles and revealed a polymorphism for drs similar to that of sic. No association was observed between the five different drs alleles and the five restriction patterns of the vir regulon for the isolates studied. These data suggest that drs sequencing may be useful for further differentiation of S. pyogenes isolates with emm12 and identical vir regulon restriction patterns.
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Affiliation(s)
- Claudia M Brandt
- Institute of Medical Microbiology and National Reference Center for Streptococci, University Hospital Aachen, 52057 Aachen, Germany.
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26
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Ma X, Kikuta H, Ishiguro N, Yoshioka M, Ebihara T, Murai T, Kobayashi I, Kobayashi K. Association of the prtF1 gene (encoding fibronectin-binding protein F1) and the sic gene (encoding the streptococcal inhibitor of complement) with emm types of group A streptococci isolated from Japanese children with pharyngitis. J Clin Microbiol 2002; 40:3835-7. [PMID: 12354893 PMCID: PMC130886 DOI: 10.1128/jcm.40.10.3835-3837.2002] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A total of 66 clinical isolates of group A streptococci (GAS) were obtained from 66 Japanese children with pharyngitis. The prtF1 gene (encoding fibronectin-binding protein F1) and the sic gene (encoding the streptococcal inhibitor of complement) were present in 51 (77.3%) and 48 (72.7%) of the 66 isolates, respectively. These results indicated that a high prevalence of two virulence genes, prtF1 and sic, is characteristic of GAS in Japan.
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Affiliation(s)
- Xiaoming Ma
- Department of Pediatrics, Hokkaido University School of Medicine, N-15 W-7, Kita-ku, Sapporo 060-8638, Japan
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27
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Affiliation(s)
- A Podbielski
- Department of Medical Microbiology and Hospital Hygiene, University Hospital of Rostock, Schillingallee 70, D-18057, Rostock, Germany.
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