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Kaewkod T, Kumseewai P, Suriyaprom S, Intachaisri V, Cheepchirasuk N, Tragoolpua Y. Potential therapeutic agents of Bombyx mori silk cocoon extracts from agricultural product for inhibition of skin pathogenic bacteria and free radicals. PeerJ 2024; 12:e17490. [PMID: 38903886 PMCID: PMC11188935 DOI: 10.7717/peerj.17490] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2023] [Accepted: 05/09/2024] [Indexed: 06/22/2024] Open
Abstract
Background Pathogenic bacteria are the cause of most skin diseases, but issues such as resistance and environmental degradation drive the need to research alternative treatments. It is reported that silk cocoon extract possesses antioxidant properties. During silk processing, the degumming of silk cocoons creates a byproduct that contains natural active substances. These substances were found to have inhibitory effects on bacterial growth, DNA synthesis, the pathogenesis of hemolysis, and biofilm formation. Thus, silk cocoon extracts can be used in therapeutic applications for the prevention and treatment of skin pathogenic bacterial infections. Methods The extract of silk cocoons with pupae (SCP) and silk cocoons without pupae (SCWP) were obtained by boiling with distilled water for 9 h and 12 h, and were compared to silkworm pupae (SP) extract that was boiled for 1 h. The active compounds in the extracts, including gallic acid and quercetin, were determined using high-performance liquid chromatography (HPLC). Furthermore, the total phenolic and flavonoid content in the extracts were investigated using the Folin-Ciocalteu method and the aluminum chloride colorimetric method, respectively. To assess antioxidant activity, the extracts were evaluated using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay. Additionally, the minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) of silk extracts and phytochemical compounds were determined against skin pathogenic bacteria. This study assessed the effects of the extracts and phytochemical compounds on growth inhibition, biofilm formation, hemolysis protection, and DNA synthesis of bacteria. Results The HPLC characterization of the silk extracts showed gallic acid levels to be the highest, especially in SCP (8.638-31.605 mg/g extract) and SP (64.530 mg/g extract); whereas quercetin compound was only detected in SCWP (0.021-0.031 mg/g extract). The total phenolics and flavonoids in silk extracts exhibited antioxidant and antimicrobial activity. Additionally, SCP at 9 h and 12 h revealed the highest anti-bacterial activity, with the lowest MIC and MBC of 50-100 mg/mL against skin pathogenic bacteria including Staphylococcus aureus, methicillin-resistant S. aureus (MRSA), Cutibacterium acnes and Pseudomonas aeruginosa. Hence, SCP extract and non-sericin compounds containing gallic acid and quercetin exhibited the strongest inhibition of both growth and DNA synthesis on skin pathogenic bacteria. The suppression of bacterial pathogenesis, including preformed and matured biofilms, and hemolysis activity, were also revealed in SCP extract and non-sericin compounds. The results show that the byproduct of silk processing can serve as an alternative source of natural phenolic and flavonoid antioxidants that can be used in therapeutic applications for the prevention and treatment of pathogenic bacterial skin infections.
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Affiliation(s)
- Thida Kaewkod
- Department of Biology, Faculty of Science, Chiang Mai University, Chiang Mai, Thailand
- Natural Extracts and Innovative Products for Alternative Healthcare Research Group, Chiang Mai University, Chiang Mai, Thailand
| | - Puangphaka Kumseewai
- Department of Biology, Faculty of Science, Chiang Mai University, Chiang Mai, Thailand
| | - Sureeporn Suriyaprom
- Department of Biology, Faculty of Science, Chiang Mai University, Chiang Mai, Thailand
- Office of Research Administration, Chiang Mai University, Chiang Mai, Thailand
| | - Varachaya Intachaisri
- Department of Biology, Faculty of Science, Chiang Mai University, Chiang Mai, Thailand
| | | | - Yingmanee Tragoolpua
- Department of Biology, Faculty of Science, Chiang Mai University, Chiang Mai, Thailand
- Natural Extracts and Innovative Products for Alternative Healthcare Research Group, Chiang Mai University, Chiang Mai, Thailand
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Rashid MH, Habib T, Bukhari SNY, Riaz F, Kolman-Taddeo D. Group B Streptococcus Persistently Colonizing the Adenosquamous Carcinoma of the Lung: A Blessing in Disguise? Cureus 2024; 16:e57377. [PMID: 38694652 PMCID: PMC11061868 DOI: 10.7759/cureus.57377] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/27/2024] [Indexed: 05/04/2024] Open
Abstract
Group B Streptococcus (GBS), also known as Streptococcus agalactiae, is a gram-negative, beta-hemolytic facultative anaerobe that causes neonatal pneumonia and sepsis. The neoplastic epithelial cells in adults, especially those of squamous origin, can show special adhesive properties toward GBS, which tends to reside within these tumors. There are some animal and human studies proving this association. Here, we present a 64-year-old female patient who had lung carcinoma of mixed adeno and squamous origin found to have persistent GBS every time the bronchoscopy was done for tumor ablation or cryotherapy. Subsequently, after starting her on chemo-radiotherapy, she also presented with multiple episodes of pneumonia caused by GBS and Pseudomonas aeruginosa. Moreover, many animal studies have shown the anti-tumor properties of GBS toxin that can prevent its metastasis and stop vascular growth surrounding the tumor. This property of GBS toxin can prove a blessing in disguise.
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Affiliation(s)
| | - Tehmina Habib
- Internal Medicine, Capital Health Regional Medical Center, Trenton, USA
| | | | - Faiqa Riaz
- Internal Medicine, Sir Syed Medical College, Karachi, PAK
| | - Diana Kolman-Taddeo
- Interventional Pulmonology, Capital Health Regional Medical Center, Trenton, USA
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Petca A, Șandru F, Negoiță S, Dumitrașcu MC, Dimcea DAM, Nedelcu T, Mehedințu C, Filipov MM, Petca RC. Antimicrobial Resistance Profile of Group B Streptococci Colonization in a Sample Population of Pregnant Women from Romania. Microorganisms 2024; 12:414. [PMID: 38399818 PMCID: PMC10893514 DOI: 10.3390/microorganisms12020414] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2023] [Revised: 01/31/2024] [Accepted: 02/16/2024] [Indexed: 02/25/2024] Open
Abstract
Group B Streptococcus (GBS) represents one of the leading causes of life-threatening invasive disease in pregnant women and neonates. Rates of GBS colonization vary by region, but studies on maternal GBS status are limited in Romania. This study aims to identify the prevalence of colonization with GBS and whether the obstetrical characteristics are statistically associated with the study group's antimicrobial susceptibility patterns of tested GBS strains. This observational study was conducted between 1 May and 31 December 2021 at The Department of Obstetrics and Gynecology at Elias University Emergency Hospital (EUEH) in Bucharest, Romania. A total of 152 samples were positive for GBS and included in the study according to the inclusion criteria. As a result, the prevalence of colonized patients with GBS was 17.3%. GBS isolated in this population had the highest resistance to erythromycin (n = 38; 25%), followed by clindamycin (n = 36; 23.7%). Regarding the susceptibility patterns of tested strains to penicillin, the 152 susceptible strains had MIC breakpoints less than 0.06 μg/μL. The susceptibility patterns of tested strains to linezolid indicated three resistant strains with low levels of resistance (MICs ranging between 2 and 3 μg/μL). Multidrug resistance (at least three antibiotic classes) was not observed. In conclusion, although GBS naturally displays sensitivity to penicillin, the exact bacterial susceptibility testing should be performed in all cases where second-line therapy is taken into consideration for treatment. We acknowledge the need for future actions to limit multidrug-resistant bacteria.
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Affiliation(s)
- Aida Petca
- Department of Obstetrics and Gynecology, “Carol Davila” University of Medicine and Pharmacy, 8 Eroii Sanitari Blvd., 050474 Bucharest, Romania; (A.P.); (M.C.D.); (D.A.-M.D.); (C.M.)
- Department of Obstetrics and Gynecology, Elias University Emergency Hospital, 17 Marasti Blvd., 011461 Bucharest, Romania
| | - Florica Șandru
- Department of Dermatology, “Carol Davila” University of Medicine and Pharmacy, 050474 Bucharest, Romania
- Department of Dermatology, Elias University Emergency Hospital, 17 Marasti Blvd., 011461 Bucharest, Romania
| | - Silvius Negoiță
- Department of Anesthesiology and Critical Care, “Carol Davila” University of Medicine and Pharmacy, 050474 Bucharest, Romania
- Department of Anesthesiology and Critical Care, Elias University Emergency Hospital, 17 Marasti Blvd., 011461 Bucharest, Romania
| | - Mihai Cristian Dumitrașcu
- Department of Obstetrics and Gynecology, “Carol Davila” University of Medicine and Pharmacy, 8 Eroii Sanitari Blvd., 050474 Bucharest, Romania; (A.P.); (M.C.D.); (D.A.-M.D.); (C.M.)
- Department of Obstetrics and Gynecology, University Emergency Hospital, 050098 Bucharest, Romania
| | - Daiana Anne-Marie Dimcea
- Department of Obstetrics and Gynecology, “Carol Davila” University of Medicine and Pharmacy, 8 Eroii Sanitari Blvd., 050474 Bucharest, Romania; (A.P.); (M.C.D.); (D.A.-M.D.); (C.M.)
- Department of Obstetrics and Gynecology, Elias University Emergency Hospital, 17 Marasti Blvd., 011461 Bucharest, Romania
| | - Tiberiu Nedelcu
- Faculty of Medicine, “Carol Davila” University of Medicine and Pharmacy, 8 Eroii Sanitari Blvd., 050474 Bucharest, Romania;
| | - Claudia Mehedințu
- Department of Obstetrics and Gynecology, “Carol Davila” University of Medicine and Pharmacy, 8 Eroii Sanitari Blvd., 050474 Bucharest, Romania; (A.P.); (M.C.D.); (D.A.-M.D.); (C.M.)
- Department of Obstetrics and Gynecology, Filantropia Clinical Hospital, 011171 Bucharest, Romania
| | - Marinela Magdalena Filipov
- Department of Laboratory Medicine, Elias University Emergency Hospital, 17 Marasti Blvd., 011461 Bucharest, Romania;
| | - Răzvan-Cosmin Petca
- Department of Urology, “Carol Davila” University of Medicine and Pharmacy, 8 Eroii Sanitari Blvd., 050474 Bucharest, Romania;
- Department of Urology, “Prof. Dr. Th. Burghele” Clinical Hospital, 20 Panduri Str., 050659 Bucharest, Romania
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Wataradee S, Boonserm T, Samngamnim S, Ajariyakhajorn K. Characterization of Virulence Factors and Antimicrobial Susceptibility of Streptococcus agalactiae Associated with Bovine Mastitis Cases in Thailand. Animals (Basel) 2024; 14:447. [PMID: 38338090 PMCID: PMC10854646 DOI: 10.3390/ani14030447] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2023] [Revised: 01/12/2024] [Accepted: 01/26/2024] [Indexed: 02/12/2024] Open
Abstract
Streptococcus agalactiae is a contagious pathogen that causes bovine mastitis. The ability of S. agalactiae to cause widespread mastitis relies on bacterial virulence factors. In this study, we detected 10 virulence determinants associated with mastitis pathogenicity using conventional PCR. The antimicrobial susceptibility of 100 S. agalactiae isolates from 13 Thai dairy herds was assessed using the Kirby-Bauer disk diffusion susceptibility test. All strains had at least three virulence factors responsible for invasion, adhesion, and infection (fbsB, bibA, and cfb, respectively). The predominant virulent profile of S. agalactiae strains revealed the presence of fbsA, fbsB, bibA, cfb, and cyl (n = 96). Most strains were sensitive to penicillin, ampicillin, amoxicillin-clavulanic acid, cefotaxime, ceftiofur, erythromycin, sulfamethoxazole-trimethoprim, and vancomycin. However, all strains were resistant to aminoglycosides, including kanamycin and gentamicin attributed to the unnecessary antimicrobial use. Furthermore, we identified seven multidrug resistant (MDR) S. agalactiae strains among four dairy herds, of which, two were vancomycin resistant. Our study provides profiles for virulence factors and antimicrobial susceptibility, which are beneficial for the clinical monitoring, prevention, and control of bovine mastitis in dairy cattle in Thailand. Moreover, we emphasize the need for awareness regarding the judicious use of antimicrobials on dairy farms.
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Affiliation(s)
| | | | | | - Kittisak Ajariyakhajorn
- Department of Veterinary Medicine, Faculty of Veterinary Science, Chulalongkorn University, Bangkok 10330, Thailand; (S.W.); (T.B.); (S.S.)
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Zakerifar M, Goli HR, Kaboosi H, Rahmani Z, Peyravii Ghadikolaii F. Capsular gene distribution and RAPD typing of Streptococcus agalactiae isolated from pregnant women. AMB Express 2024; 14:13. [PMID: 38282173 PMCID: PMC10822826 DOI: 10.1186/s13568-024-01671-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2023] [Accepted: 01/16/2024] [Indexed: 01/30/2024] Open
Abstract
Streptococcus agalactiae has different virulence factors, from which the capsule has the most significant role in the pathogenesis of this organism. We aimed to investigate the distribution of more prevalent capsular genes among different Random Amplified Polymorphic DNA (RAPD) types of S. agalactiae isolated from pregnant women. A total of 106 isolates were collected from 420 vaginal and rectal swabs obtained from pregnant women. The specimens were transferred using Todd Hewitt Broth and were cultured on a blood agar containing antibiotics. The S. agalactiae isolates were identified by the standard microbiological and biochemical tests. The genomic DNAs of S. agalactiae isolates were extracted using an extraction kit. Then, the PCR method was used to detection of the capsular genes. Moreover, The RAPD PCR was used to genotyping of the isolates. The colonization rate of the pregnant women was 25.23%, and there was a statistically significant correlation between the weeks of gestation and the probability of colonization (p-value < 0.05). Also, 31 (29.24%) and 18 (16.98%) pregnant women had a history of abortion and membrane rupture, respectively. In addition, 20 (18.86%), 32 (30.18%), 4 (3.77%), and 6 (5.66%) isolates carried genes encoding capsular types Ia, Ib, III, and V, respectively. None isolates had the type II capsular gene, and other 44 isolates were non-typeable. Nine clones (clusters) of S. agalactiae were observed in the present study with 70% similarity, and 53 different types were identified among the isolates. Except for capsular types III and V that belonged to clones 3, 5, 7, and 9, other capsular types were detected in different RAPD types. We found that the capsular types Ib and Ia were predominant among pregnant women in this area, indicating their significance for vaccine designation. Also, our isolates showed a lower genotypic diversity in RAPD typing. This may be due to the same sources of most isolates.
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Affiliation(s)
- Mona Zakerifar
- Department of Microbiology, Ayatollah Amoli Branch, Islamic Azad University, Amol, Iran
| | - Hamid Reza Goli
- Molecular and Cell Biology Research Centre, Faculty of Medicine, Mazandaran University of Medical Sciences, Sari, Iran.
- Department of Medical Microbiology and Virology, Faculty of Medicine, Mazandaran University of Medical Sciences, Sari, Iran.
| | - Hami Kaboosi
- Department of Microbiology, Ayatollah Amoli Branch, Islamic Azad University, Amol, Iran.
| | - Zahra Rahmani
- Department of Obstetrics and Gynecology, Faculty of Medicine, Mazandaran University of Medical Sciences, Sari, Iran
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Alzayer M, Alkhulaifi MM, Alyami A, Aldosary M, Alageel A, Garaween G, Shibl A, Al-Hamad AM, Doumith M. Molecular typing and antimicrobial resistance of group B Streptococcus clinical isolates in Saudi Arabia. J Glob Antimicrob Resist 2023; 35:244-251. [PMID: 37844802 DOI: 10.1016/j.jgar.2023.10.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2023] [Accepted: 10/06/2023] [Indexed: 10/18/2023] Open
Abstract
OBJECTIVES Group B Streptococcus (GBS) has emerged as an important cause of severe infections in adults. However, limited data are available regarding the epidemiology of GBS in Saudi Arabia. METHODS Isolates were collected over a period of eight months from colonized (n = 104) and infected adults (n = 95). Serotypes and virulence determinants were detected by polymerase chain reactions (PCRs). Genetic relatedness was assessed using Multiple Locus Variable Number Tandem Repeat Analysis (MLVA). Antimicrobial susceptibilities were determined by disk diffusion. RESULTS Serotypes III and V (25% each) were the most prevalent, followed by serotypes II (16.18%), Ia (13.24%), VI (9.31%), and Ib (8.82%), while five isolates remained non-typeable (2.45%). Hypervirulent serotype III/CC17 clone (n = 21) accounted for 41.18% of the serotype III isolates. Most isolates (53.92%) harboured pilus island (PI) 1 and 2a types, while PI-2b was predominantly detected in the hypervirulent clone. Isolates were variably resistant to tetracycline (76.47%), erythromycin (36.76%), clindamycin (25.49%), and levofloxacin (6.37%), but remained susceptible to penicillin. Macrolide resistant isolates exhibited constitutive (55.42%) and inducible macrolide-lincosamide-streptogramin B resistance phenotypes (33.74%), while a few had L (9.64%) or M (1.2%) phenotypes. MLVA patterns of dominant serotypes III and V revealed 40 different types divided into 12 clusters and 28 singletons. Interestingly, macrolide resistance was significantly associated with two major MLVA types. CONCLUSIONS GBS isolates belonged predominantly to serotypes III and V, but there were no clear associations between serotypes and patient groups. The studied isolates exhibited high levels of resistance to erythromycin and clindamycin that need further surveillance.
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Affiliation(s)
- Maha Alzayer
- Department of Botany and Microbiology, College of Science, King Saud University, Riyadh, Saudi Arabia; Department of Microbiology and Immunology, College of Medicine, Alfaisal University, Riyadh, Saudi Arabia.
| | - Manal M Alkhulaifi
- Department of Botany and Microbiology, College of Science, King Saud University, Riyadh, Saudi Arabia
| | - Ahmed Alyami
- Pathology and Clinical Laboratory, Medicine Administration, King Fahad Medical City, Riyadh, Saudi Arabia
| | - Mohammed Aldosary
- Pathology and Clinical Laboratory, Medicine Administration, King Fahad Medical City, Riyadh, Saudi Arabia
| | - Abdulaziz Alageel
- Pathology and Clinical Laboratory, Medicine Administration, King Fahad Medical City, Riyadh, Saudi Arabia
| | - Ghada Garaween
- Department of Microbiology and Immunology, College of Medicine, Alfaisal University, Riyadh, Saudi Arabia
| | - Atef Shibl
- Department of Microbiology and Immunology, College of Medicine, Alfaisal University, Riyadh, Saudi Arabia
| | - Arif M Al-Hamad
- Division of Clinical Microbiology, Pathology and Laboratory Medicine, Qatif Central Hospital, Qatif, Saudi Arabia
| | - Michel Doumith
- Infectious Diseases Research Department, King Abdullah International Medical Research Center, Riyadh, Saudi Arabia
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Gopal N, Chauhan N, Jain U, Dass SK, Sharma HS, Chandra R. Advancement in biomarker based effective diagnosis of neonatal sepsis. ARTIFICIAL CELLS, NANOMEDICINE, AND BIOTECHNOLOGY 2023; 51:476-490. [PMID: 37656048 DOI: 10.1080/21691401.2023.2252016] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2022] [Revised: 08/17/2023] [Accepted: 08/18/2023] [Indexed: 09/02/2023]
Abstract
Neonatal sepsis is considered as alarming medical emergency and becomes the common global reason of neonatal mortality. Non-specific symptoms and limitations of conventional diagnostic methods for neonatal sepsis mandate fast and reliable method to diagnose disease for point of care application. Recently, disease specific biomarkers have gained interest for rapid diagnosis that led to the development of electrochemical biosensor with enhanced specificity, sensitivity, cost-effectiveness and user-friendliness. Other than conventional biomarker C-reactive protein to diagnose neonatal sepsis, several potential biomarkers including Procalcitonin (PCT), Serum amyloid A (SAA) and other candidates are extensively investigated. The present review provides insights on advancements and diagnostic abilities of protein and nucleotide based biomarkers with their incorporation in developing electrochemical biosensors by employing novel fabrication strategies. This review provides an overview of most promising biomarker and its capability for neonatal sepsis diagnosis to fulfil future demand to develop electrochemical biosensor for point-of-care applications.
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Affiliation(s)
- Neha Gopal
- Department of Chemistry, University of Delhi, Delhi, India
| | - Nidhi Chauhan
- Amity Institute of Nanotechnology, Amity University, Noida, Uttar Pradesh, India
| | - Utkarsh Jain
- Amity Institute of Nanotechnology, Amity University, Noida, Uttar Pradesh, India
| | - Sujata K Dass
- Department of Neurology, BLK Super Speciality Hospital, New Delhi, India
| | - Hari S Sharma
- Department of Pathology and Clinical Bioinformatics, Erasmus MC, University Medical Center, Rotterdam, The Netherlands
| | - Ramesh Chandra
- Department of Chemistry, University of Delhi, Delhi, India
- Institute of Nanomedical Sciences (INMS), University of Delhi, Delhi, India
- Dr. B. R. Ambedkar Center for Biomedical Research, University of Delhi, Delhi, India
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Jusuf S, Dong PT. Chromophore-Targeting Precision Antimicrobial Phototherapy. Cells 2023; 12:2664. [PMID: 37998399 PMCID: PMC10670386 DOI: 10.3390/cells12222664] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2023] [Revised: 11/11/2023] [Accepted: 11/18/2023] [Indexed: 11/25/2023] Open
Abstract
Phototherapy, encompassing the utilization of both natural and artificial light, has emerged as a dependable and non-invasive strategy for addressing a diverse range of illnesses, diseases, and infections. This therapeutic approach, primarily known for its efficacy in treating skin infections, such as herpes and acne lesions, involves the synergistic use of specific light wavelengths and photosensitizers, like methylene blue. Photodynamic therapy, as it is termed, relies on the generation of antimicrobial reactive oxygen species (ROS) through the interaction between light and externally applied photosensitizers. Recent research, however, has highlighted the intrinsic antimicrobial properties of light itself, marking a paradigm shift in focus from exogenous agents to the inherent photosensitivity of molecules found naturally within pathogens. Chemical analyses have identified specific organic molecular structures and systems, including protoporphyrins and conjugated C=C bonds, as pivotal components in molecular photosensitivity. Given the prevalence of these systems in organic life forms, there is an urgent need to investigate the potential impact of phototherapy on individual molecules expressed within pathogens and discern their contributions to the antimicrobial effects of light. This review delves into the recently unveiled key molecular targets of phototherapy, offering insights into their potential downstream implications and therapeutic applications. By shedding light on these fundamental molecular mechanisms, we aim to advance our understanding of phototherapy's broader therapeutic potential and contribute to the development of innovative treatments for a wide array of microbial infections and diseases.
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Affiliation(s)
- Sebastian Jusuf
- Division of Infectious Diseases, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA;
| | - Pu-Ting Dong
- Department of Microbiology, The Forsyth Institute, Boston, MA 02142, USA
- Department of Oral Medicine, Infection and Immunity, Harvard School of Dental Medicine, Boston, MA 02115, USA
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Schar D, Zhang Z, Pires J, Vrancken B, Suchard MA, Lemey P, Ip M, Gilbert M, Van Boeckel T, Dellicour S. Dispersal history and bidirectional human-fish host switching of invasive, hypervirulent Streptococcus agalactiae sequence type 283. PLOS GLOBAL PUBLIC HEALTH 2023; 3:e0002454. [PMID: 37856430 PMCID: PMC10586614 DOI: 10.1371/journal.pgph.0002454] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2023] [Accepted: 09/25/2023] [Indexed: 10/21/2023]
Abstract
Human group B Streptococcus (GBS) infections attributable to an invasive, hypervirulent sequence type (ST) 283 have been associated with freshwater fish consumption in Asia. The origin, geographic dispersion pathways and host transitions of GBS ST283 remain unresolved. We gather 328 ST283 isolate whole-genome sequences collected from humans and fish between 1998 and 2021, representing eleven countries across four continents. We apply Bayesian phylogeographic analyses to reconstruct the dispersal history of ST283 and combine ST283 phylogenies with genetic markers and host association to investigate host switching and the gain and loss of antimicrobial resistance and virulence factor genes. Initial dispersal within Asia followed ST283 emergence in the early 1980s, with Singapore, Thailand and Hong Kong observed as early transmission hubs. Subsequent intercontinental dispersal originating from Vietnam began in the decade commencing 2001, demonstrating ST283 holds potential to expand geographically. Furthermore, we observe bidirectional host switching, with the detection of more frequent human-to-fish than fish-to-human transitions, suggesting that sound wastewater management, hygiene and sanitation may help to interrupt chains of transmission between hosts. We also show that antimicrobial resistance and virulence factor genes were lost more frequently than gained across the evolutionary history of ST283. Our findings highlight the need for enhanced surveillance, clinical awareness, and targeted risk mitigation to limit transmission and reduce the impact of an emerging pathogen associated with a high-growth aquaculture industry.
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Affiliation(s)
- Daniel Schar
- Spatial Epidemiology Laboratory, Université Libre de Bruxelles, Brussels, Belgium
| | - Zhenyu Zhang
- Department of Biostatistics, Fielding School of Public Health, University of California, Los Angeles, Los Angeles, CA, United States of America
| | - Joao Pires
- Institute for Environmental Decisions, ETH Zurich, Zurich, Switzerland
| | - Bram Vrancken
- Spatial Epidemiology Laboratory, Université Libre de Bruxelles, Brussels, Belgium
- Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical Research, KU Leuven, Leuven, Belgium
| | - Marc A. Suchard
- Department of Biostatistics, Fielding School of Public Health, University of California, Los Angeles, Los Angeles, CA, United States of America
- Department of Human Genetics, David Geffen School of Medicine at UCLA, University of California, Los Angeles, Los Angeles, CA, United States of America
| | - Philippe Lemey
- Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical Research, KU Leuven, Leuven, Belgium
| | - Margaret Ip
- Department of Microbiology, Faculty of Medicine, Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong SAR, China
| | - Marius Gilbert
- Spatial Epidemiology Laboratory, Université Libre de Bruxelles, Brussels, Belgium
- Fonds National de la Recherche Scientifique, Brussels, Belgium
| | - Thomas Van Boeckel
- Institute for Environmental Decisions, ETH Zurich, Zurich, Switzerland
- Center for Diseases Dynamics, Economics, and Policy, New Delhi, India
| | - Simon Dellicour
- Spatial Epidemiology Laboratory, Université Libre de Bruxelles, Brussels, Belgium
- Department of Microbiology, Immunology and Transplantation, Rega Institute for Medical Research, KU Leuven, Leuven, Belgium
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Wahlenmayer ER, Hammers DE. Streptococcal peptides and their roles in host-microbe interactions. Front Cell Infect Microbiol 2023; 13:1282622. [PMID: 37915845 PMCID: PMC10617681 DOI: 10.3389/fcimb.2023.1282622] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2023] [Accepted: 10/02/2023] [Indexed: 11/03/2023] Open
Abstract
The genus Streptococcus encompasses many bacterial species that are associated with hosts, ranging from asymptomatic colonizers and commensals to pathogens with a significant global health burden. Streptococci produce numerous factors that enable them to occupy their host-associated niches, many of which alter their host environment to the benefit of the bacteria. The ability to manipulate host immune systems to either evade detection and clearance or induce a hyperinflammatory state influences whether bacteria are able to survive and persist in a given environment, while also influencing the propensity of the bacteria to cause disease. Several bacterial factors that contribute to this inter-species interaction have been identified. Recently, small peptides have become increasingly appreciated as factors that contribute to Streptococcal relationships with their hosts. Peptides are utilized by streptococci to modulate their host environment in several ways, including by directly interacting with host factors to disrupt immune system function and signaling to other bacteria to control the expression of genes that contribute to immune modulation. In this review, we discuss the many contributions of Streptococcal peptides in terms of their ability to contribute to pathogenesis and disruption of host immunity. This discussion will highlight the importance of continuing to elucidate the functions of these Streptococcal peptides and pursuing the identification of new peptides that contribute to modulation of host environments. Developing a greater understanding of how bacteria interact with their hosts has the potential to enable the development of techniques to inhibit these peptides as therapeutic approaches against Streptococcal infections.
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Affiliation(s)
| | - Daniel E. Hammers
- Biology Department, Houghton University, Houghton, NY, United States
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Varghese BR, Goh KGK, Desai D, Acharya D, Chee C, Sullivan MJ, Ulett GC. Variable resistance to zinc intoxication among Streptococcus agalactiae reveals a novel IS1381 insertion element within the zinc efflux transporter gene czcD. Front Immunol 2023; 14:1174695. [PMID: 37304277 PMCID: PMC10251203 DOI: 10.3389/fimmu.2023.1174695] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2023] [Accepted: 04/11/2023] [Indexed: 06/13/2023] Open
Abstract
Streptococcus agalactiae, also known as group B Streptococcus, is an important human and animal pathogen. Zinc (Zn) is an essential trace element for normal bacterial physiology but intoxicates bacteria at high concentrations. Molecular systems for Zn detoxification exist in S. agalactiae, however the degree to which Zn detoxification may vary among different S. agalactiae isolates is not clear. We measured resistance to Zn intoxication in a diverse collection of clinical isolates of S. agalactiae by comparing the growth of the bacteria in defined conditions of Zn stress. We found significant differences in the ability of different S. agalactiae isolates to resist Zn intoxication; some strains such as S. agalactiae 18RS21 were able to survive and grow at 3.8-fold higher levels of Zn stress compared to other reference strains such as BM110 (6.4mM vs 1.68mM Zn as inhibitory, respectively). We performed in silico analysis of the available genomes of the S. agalactiae isolates used in this study to examine the sequence of czcD, which encodes an efflux protein for Zn that supports resistance in S. agalactiae. Interestingly, this revealed the presence of a mobile insertion sequence (IS) element, termed IS1381, in the 5' region of czcD in S. agalactiae strain 834, which was hyper-resistant to Zn intoxication. Interrogating a wider collection of S. agalactiae genomes revealed identical placement of IS1381 in czcD in other isolates from the clonal-complex-19 (CC19) 19 lineage. Collectively, these results show a resistance spectrum among S. agalactiae isolates enables survival in varying degrees of Zn stress, and this phenotypic variability has implications for understanding bacterial survival in metal stress.
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Affiliation(s)
- Brian R. Varghese
- School of Pharmacy and Medical Sciences, Menzies Health Institute Queensland, Griffith University, Gold Coast, QLD, Australia
| | - Kelvin G. K. Goh
- School of Pharmacy and Medical Sciences, Menzies Health Institute Queensland, Griffith University, Gold Coast, QLD, Australia
| | - Devika Desai
- School of Pharmacy and Medical Sciences, Menzies Health Institute Queensland, Griffith University, Gold Coast, QLD, Australia
| | - Dhruba Acharya
- School of Pharmacy and Medical Sciences, Menzies Health Institute Queensland, Griffith University, Gold Coast, QLD, Australia
| | - Collin Chee
- School of Pharmacy and Medical Sciences, Menzies Health Institute Queensland, Griffith University, Gold Coast, QLD, Australia
| | - Matthew J. Sullivan
- School of Pharmacy and Medical Sciences, Menzies Health Institute Queensland, Griffith University, Gold Coast, QLD, Australia
| | - Glen C. Ulett
- School of Pharmacy and Medical Sciences, Menzies Health Institute Queensland, Griffith University, Gold Coast, QLD, Australia
- Department of Medicine, University of Alabama at Birmingham, Birmingham, AL, United States
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12
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Zhou J, Zhang L, Zhang Y, Liu H, Xu K, Zhang B, Feng T, Yang S. Analysis of molecular characteristics of CAMP-negative Streptococcus agalactiae strains. Front Microbiol 2023; 14:1189093. [PMID: 37293216 PMCID: PMC10244789 DOI: 10.3389/fmicb.2023.1189093] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2023] [Accepted: 05/03/2023] [Indexed: 06/10/2023] Open
Abstract
Background Streptococcus agalactiae can produce CAMP factor, which can promote the β-hemolysin activity of Staphylococcus aureus, forming an arrow-shaped hemolysis enhancement zone at the intersection of the two bacterial species on a blood agar plate. This characteristic feature of Streptococcus agalactiae has led to the widespread use of the CAMP test as an identification method. Methods Vaginal/rectal swabs, collected from women at 35-37 weeks of pregnancy, were first inoculated into a selective enrichment broth media, then subcultured onto GBS chromogenic agar and 5% sheep blood agar sequentially. The VITEK-2 automatic identification system and MALDI-TOF MS were initially employed for identification, followed by the CAMP test. CAMP-negative strains underwent 16S rDNA and cfb gene sequence analysis, as well as bacterial multilocus sequence typing. Results A total of 190 strains were isolated, with 15 identified as CAMP-negative. Further 16S rDNA gene sequence analysis confirmed that all 15 strains were Streptococcus agalactiae. The MLST typing assay revealed that these 15 strains were of the ST862 type. The cfb gene was amplified and electrophoresed, but no specific fragments were found, indicating that these strains lack the CAMP factor due to cfb gene deletion. Antibiotic susceptibility tests demonstrated no resistance to penicillin, ampicillin, vancomycin and linezolid among the GBS strains. However, there are significant differences in resistance rates to tetracycline. Conclusion This study found that 7.9% of GBS strains isolated from the vagina/rectum of pregnant women were CAMP-negative, suggesting that the CAMP test method or primers targeting the cfb gene should not be used as the sole presumptive test for GBS identification.
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Affiliation(s)
- Jie Zhou
- Department of Clinical Laboratory, Pingshan General Hospital, Southern Medical University (Pingshan District People’s Hospital of Shenzhen), Shenzhen, Guangdong, China
| | - Li Zhang
- Department of Clinical Laboratory, Pingshan General Hospital, Southern Medical University (Pingshan District People’s Hospital of Shenzhen), Shenzhen, Guangdong, China
| | - Yang Zhang
- Department of Clinical Laboratory, Pingshan General Hospital, Southern Medical University (Pingshan District People’s Hospital of Shenzhen), Shenzhen, Guangdong, China
| | - Hui Liu
- Department of Pharmacy, Pingshan General Hospital, Southern Medical University (Pingshan District People’s Hospital of Shenzhen), Shenzhen, Guangdong, China
| | - Kangli Xu
- Department of Clinical Laboratory, Pingshan General Hospital, Southern Medical University (Pingshan District People’s Hospital of Shenzhen), Shenzhen, Guangdong, China
| | - Baohu Zhang
- Department of Clinical Laboratory, Pingshan General Hospital, Southern Medical University (Pingshan District People’s Hospital of Shenzhen), Shenzhen, Guangdong, China
| | - Tianyuan Feng
- Department of Clinical Laboratory, Pingshan General Hospital, Southern Medical University (Pingshan District People’s Hospital of Shenzhen), Shenzhen, Guangdong, China
| | - Shucai Yang
- Department of Clinical Laboratory, Pingshan General Hospital, Southern Medical University (Pingshan District People’s Hospital of Shenzhen), Shenzhen, Guangdong, China
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Balasubramanian N, Pounpandi P, Varatharaju G, Shanmugaiah V, Balakrishnan K, Thirunarayan MA. Distribution of virulence genes and biofilm characterization of human isolates of Streptococcus agalactiae: A pilot study. Colloids Surf B Biointerfaces 2023; 223:113151. [PMID: 36738701 DOI: 10.1016/j.colsurfb.2023.113151] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2022] [Revised: 01/13/2023] [Accepted: 01/16/2023] [Indexed: 01/19/2023]
Abstract
This study included 21 newly isolated clinical samples of Streptococcus agalactiae (Group B Streptococcus) screened in patients (six male, fifteen female) from various states of India with different infections (urinary tract infections, blood, pus and eye infections). All isolates were identified as Group B Streptococcus (GBS) using hemolytic properties, serogrouping and MALDI-TOF-MS analysis. Six virulence genes, cfb (100%), cylE (90.4%), lmp (85.7%), bca (71.4%), rib (38%) and bac (4.7%) were detected via polymerase chain reaction (PCR). Distribution studies of these six genes revealed five isolates containing five virulence genes (23.8%), followed by ten isolates containing four virulence genes (47.6%). The twenty GBS isolates selected on the glass surface included non-biofilm producers (n = 6, 30%), weak (n = 11, 55%) and moderate biofilm producers (n = 3, 15%). On the polystyrene surface, weak (n = 4, 20%), moderate (n = 2, 10%) and strong (n = 14, 70%) biofilm producers were detected. Live-dead cell staining revealed that more viable cells accumulated in the S. ag 7420 isolate than in the AH1 isolate. Scanning electron microscope (SEM) biofilm analysis showed S. ag AH1 cells appeared as chain-like structures, whereas the S. ag 7420 isolate biofilm cells appeared as fork-like structures on the glass surface. Biofilm elements were analyzed using Energy Dispersive X-Ray Analysis (EDAX) for both isolates and 13 elements with different orders of composition were found. Thus, virulence gene detection, distribution and biofilm formation by these new clinical isolates suggested the virulent nature of these pathogens, which might cause different levels of disease severity in humans.
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Affiliation(s)
- N Balasubramanian
- Department of Immunology, School of Biological Sciences, Madurai Kamaraj University, Madurai 625021, India.
| | - P Pounpandi
- Department of Immunology, School of Biological Sciences, Madurai Kamaraj University, Madurai 625021, India
| | - G Varatharaju
- Department of Microbial Technology, School of Biological Sciences, Madurai Kamaraj University, Madurai 625021, India
| | - V Shanmugaiah
- Department of Microbial Technology, School of Biological Sciences, Madurai Kamaraj University, Madurai 625021, India
| | - K Balakrishnan
- Department of Immunology, School of Biological Sciences, Madurai Kamaraj University, Madurai 625021, India
| | - M A Thirunarayan
- Department of Microbiology, Apollo Hospitals, Greams Road, Chennai 600006, India
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14
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Bonsaglia ECR, Rossi RS, Latosinski G, Rossi BF, Campos FC, Junior AF, Pantoja JCF, Rall VLM. Relationship between Biofilm Production and High Somatic Cell Count in Streptococcus agalactiae Isolated from Milk of Cows with Subclinical Mastitis. Pathogens 2023; 12:pathogens12020311. [PMID: 36839583 PMCID: PMC9966988 DOI: 10.3390/pathogens12020311] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2022] [Revised: 01/30/2023] [Accepted: 02/08/2023] [Indexed: 02/16/2023] Open
Abstract
Streptococcus agalactiae (S. agalactiae) is one of the main agents that causes mastitis in dairy cows, mainly inducing the subclinical form, which is characterized by a high somatic cell count (SCC). The aim of this study was to correlate the increase in SCC caused by S. agalactiae in cows with subclinical mastitis to the presence of genes related to adhesion and invasion in bovine mammary epithelial cells (BMEC) and biofilm formation. Considering the 145 isolates tested, 57.2% presented the capsular type Ia and 42.8% presented type III. We identified the virulence genes among the isolates and determined nine genetic profiles. The most common profile was identified in 69 isolates (47.5%): Ia, fbsA+, fbsB-, pI1-, pI2a-, pI2b+, and hylb+. All isolates produced biofilm, with 58.6% classified as strong producers, 29% as moderate producers and 12.4% as weak producers. No statistical correlation was found between the presence of virulence genes and increased SCC or biofilm production. However, biological evidence was observed between increased SCC and biofilm production. One isolate from each profile was randomly subjected to adhesion and invasion assays, and all of them adhered to BEMC, but none were able to invade. Our results showed that different genetic profiles do not provide advantages for bacteria to invade BMEC in vitro. In addition, biofilm production appears to be related to high SCC.
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Affiliation(s)
- Erika Carolina Romão Bonsaglia
- Department of Chemical and Biological Sciences, Institute of Biosciences, Sao Paulo State University (UNESP), Botucatu 18618-970, SP, Brazil
- Correspondence: (E.C.R.B.); (V.L.M.R.); Tel.: +5514-3880-0438 (V.L.M.R.)
| | - Rodolfo S. Rossi
- Department of Veterinary Hygiene and Public Health, Sao Paulo State University (UNESP), Botucatu 18618-970, SP, Brazil
| | - Giulia Latosinski
- Department of Veterinary Hygiene and Public Health, Sao Paulo State University (UNESP), Botucatu 18618-970, SP, Brazil
| | - Bruna Fernanda Rossi
- Department of Chemical and Biological Sciences, Institute of Biosciences, Sao Paulo State University (UNESP), Botucatu 18618-970, SP, Brazil
| | - Fernanda Cristina Campos
- Department of Chemical and Biological Sciences, Institute of Biosciences, Sao Paulo State University (UNESP), Botucatu 18618-970, SP, Brazil
| | - Ary Fernandes Junior
- Department of Chemical and Biological Sciences, Institute of Biosciences, Sao Paulo State University (UNESP), Botucatu 18618-970, SP, Brazil
| | - José Carlos F. Pantoja
- Department of Veterinary Hygiene and Public Health, Sao Paulo State University (UNESP), Botucatu 18618-970, SP, Brazil
| | - Vera Lucia Mores Rall
- Department of Chemical and Biological Sciences, Institute of Biosciences, Sao Paulo State University (UNESP), Botucatu 18618-970, SP, Brazil
- Correspondence: (E.C.R.B.); (V.L.M.R.); Tel.: +5514-3880-0438 (V.L.M.R.)
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15
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Nanayakkara U, Khan MA, Hargun DK, Sivagnanam S, Samarawickrama C. Ocular streptococcal infections: A clinical and microbiological review. Surv Ophthalmol 2023:S0039-6257(23)00036-X. [PMID: 36764397 DOI: 10.1016/j.survophthal.2023.02.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2022] [Revised: 01/30/2023] [Accepted: 02/01/2023] [Indexed: 02/11/2023]
Abstract
Streptococcus is a diverse bacterial genus that is part of the ocular surface microbiome implicated in conjunctivitis, keratitis, endophthalmitis, dacryocystitis, and orbital cellulitis which can lead to decreased visual acuity and require surgical intervention. The pathophysiology of S. pneumoniae is well established and the role of the polysaccharide capsule, pneumolysin, neuraminidases, and zinc metalloproteinases in ocular infections described. Additionally, key virulence factors of the viridans group streptococci such as cytolysins and proteases have been outlined, but there is a paucity of research on the remaining streptococcus species. These virulence factors tend to result in aggressive disease. Clinically, S. pneumoniae is implicated in 2.7-41.2% of bacterial conjunctivitis cases, more predominant in the pediatric population, and is implicated in 1.8-10.7% of bacterial keratitis isolates. Streptococcus bacteria are significantly implicated in acute postoperative, post-intravitreal, and bleb-associated endophthalmitis, responsible for 10.3-37.5, 29.4, and 57.1% of cases, respectively. Group A and B streptococcus endogenous endophthalmitis is rare, but has a very poor prognosis. Inappropriate prescription of antibiotics in cases of non-bacterial aetiology has contributed to increasing resistance, and a clinical index is needed to more accurately monitor this. Furthermore, there is an increasing need for prospective, surveillance studies of antimicrobial resistance in ocular pathogens, as well as point-of-care testing using molecular techniques.
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Affiliation(s)
| | | | | | - Shobini Sivagnanam
- Blacktown Hospital, Sydney, Australia; Australian Clinical Labs, Bella Vista, Sydney, Australia
| | - Chameen Samarawickrama
- University of Sydney, Australia; Translational Ocular Research and Immunology Consortium (TORIC), Westmead Institute for Medical Research, Australia.
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16
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Janžič L, Repas J, Pavlin M, Zemljić-Jokhadar Š, Ihan A, Kopitar AN. Macrophage polarization during Streptococcus agalactiae infection is isolate specific. Front Microbiol 2023; 14:1186087. [PMID: 37213504 PMCID: PMC10192866 DOI: 10.3389/fmicb.2023.1186087] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2023] [Accepted: 04/17/2023] [Indexed: 05/23/2023] Open
Abstract
Introduction Streptococcus agalactiae (Group B Streptococcus, GBS), a Gram-positive commensal in healthy adults, remains a major cause of neonatal infections, usually manifesting as sepsis, meningitis, or pneumonia. Intrapartum antibiotic prophylaxis has greatly reduced the incidence of early-onset disease. However, given the lack of effective measures to prevent the risk of late-onset disease and invasive infections in immunocompromised individuals, more studies investigating the GBS-associated pathogenesis and the interplay between bacteria and host immune system are needed. Methods Here, we examined the impact of 12 previously genotyped GBS isolates belonging to different serotypes and sequence types on the immune response of THP-1 macrophages. Results Flow cytometry analysis showed isolate-specific differences in phagocytic uptake, ranging from 10% for isolates of serotype Ib, which possess the virulence factor protein β, to over 70% for isolates of serotype III. Different isolates also induced differential expression of co-stimulatory molecules and scavenger receptors with colonizing isolates inducing higher expression levels of CD80 and CD86 compared to invasive isolates. In addition, real-time measurements of metabolism revealed that macrophages enhanced both glycolysis and mitochondrial respiration after GBS infection, with isolates of serotype III being the most potent activators of glycolysis and glycolytic ATP production. Macrophages also showed differential resistance to GBS-mediated cell cytotoxicity as measured by LDH release and real-time microscopy. The differences were evident both between serotypes and between isolates obtained from different specimens (colonizing or invasive isolates) demonstrating the higher cytotoxicity of vaginal compared with blood isolates. Conclusions Thus, the data suggest that GBS isolates differ in their potential to become invasive or remain colonizing. In addition, colonizing isolates appear to be more cytotoxic, whereas invasive isolates appear to exploit macrophages to their advantage, avoiding the immune recognition and antibiotics.
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Affiliation(s)
- Larisa Janžič
- Department of Cell Immunology, Institute of Microbiology and Immunology, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia
| | - Jernej Repas
- Institute of Biophysics, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia
| | - Mojca Pavlin
- Institute of Biophysics, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia
- Group for Nano and Biotechnological Applications, Faculty of Electrical Engineering, University of Ljubljana, Ljubljana, Slovenia
| | - Špela Zemljić-Jokhadar
- Institute of Biophysics, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia
| | - Alojz Ihan
- Department of Cell Immunology, Institute of Microbiology and Immunology, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia
| | - Andreja Nataša Kopitar
- Department of Cell Immunology, Institute of Microbiology and Immunology, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia
- *Correspondence: Andreja Nataša Kopitar,
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Shabayek S, Abdellah AM, Salah M, Ramadan M, Fahmy N. Alterations of the vaginal microbiome in healthy pregnant women positive for group B Streptococcus colonization during the third trimester. BMC Microbiol 2022; 22:313. [PMID: 36544085 PMCID: PMC9769055 DOI: 10.1186/s12866-022-02730-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2022] [Accepted: 12/09/2022] [Indexed: 12/24/2022] Open
Abstract
BACKGROUND Streptococcus agalactiae or group B Streptococcus (GBS) asymptomatically colonizes the genitourinary tracts of up to 30% of pregnant women. Globally, GBS is an important cause of neonatal morbidity and mortality. GBS has recently been linked to adverse pregnancy outcomes. The potential interactions between GBS and the vaginal microbiome composition remain poorly understood. In addition, little is known about the vaginal microbiota of pregnant Egyptian women. RESULTS Using V3-V4 16S rRNA next-generation sequencing, we examined the vaginal microbiome in GBS culture-positive pregnant women (22) and GBS culture-negative pregnant women (22) during the third trimester in Ismailia, Egypt. According to the alpha-diversity indices, the vaginal microbiome of pregnant GBS culture-positive women was significantly more diverse and less homogenous. The composition of the vaginal microbiome differed significantly based on beta-diversity between GBS culture-positive and culture-negative women. The phylum Firmicutes and the family Lactobacillaceae were significantly more abundant in GBS-negative colonizers. In contrast, the phyla Actinobacteria, Tenericutes, and Proteobacteria and the families Bifidobacteriaceae, Mycoplasmataceae, Streptococcaceae, Corynebacteriaceae, Staphylococcaceae, and Peptostreptococcaceae were significantly more abundant in GBS culture-positive colonizers. On the genus and species levels, Lactobacillus was the only genus detected with significantly higher relative abundance in GBS culture-negative status (88%), and L. iners was the significantly most abundant species. Conversely, GBS-positive carriers exhibited a significant decrease in Lactobacillus abundance (56%). In GBS-positive colonizers, the relative abundance of the genera Ureaplasma, Gardnerella, Streptococcus, Corynebacterium, Staphylococcus, and Peptostreptococcus and the species Peptostreptococcus anaerobius was significantly higher. The Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways related to the metabolism of cofactors and vitamins, phosphatidylinositol signaling system, peroxisome, host immune system pathways, and host endocrine system were exclusively enriched among GBS culture-positive microbial communities. However, lipid metabolism KEGG pathways, nucleotide metabolism, xenobiotics biodegradation and metabolism, genetic information processing pathways associated with translation, replication, and repair, and human diseases (Staphylococcus aureus infection) were exclusively enriched in GBS culture-negative communities. CONCLUSIONS Understanding how perturbations of the vaginal microbiome contribute to pregnancy complications may result in the development of alternative, targeted prevention strategies to prevent maternal GBS colonization. We hypothesized associations between inferred microbial function and GBS status that would need to be confirmed in larger cohorts.
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Affiliation(s)
- Sarah Shabayek
- grid.33003.330000 0000 9889 5690Department of Microbiology and Immunology, Faculty of Pharmacy, Suez Canal University, Ismailia, Egypt
| | - Asmaa M. Abdellah
- grid.33003.330000 0000 9889 5690Department of Obstetrics and Gynecology, Faculty of Medicine, Suez Canal University, Ismailia, Egypt
| | - Mohammed Salah
- grid.440879.60000 0004 0578 4430Department of Microbiology and Immunology, Faculty of Pharmacy, Port Said University, Port Said, Egypt
| | - Mohammed Ramadan
- grid.411303.40000 0001 2155 6022Department of Microbiology and Immunology, Faculty of Pharmacy, Al-Azhar University, Assiut, Egypt
| | - Nora Fahmy
- grid.33003.330000 0000 9889 5690Department of Microbiology and Immunology, Faculty of Pharmacy, Suez Canal University, Ismailia, Egypt
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Keogh RA, Haeberle AL, Langouët-Astrié CJ, Kavanaugh JS, Schmidt EP, Moore GD, Horswill AR, Doran KS. Group B Streptococcus adaptation promotes survival in a hyperinflammatory diabetic wound environment. SCIENCE ADVANCES 2022; 8:eadd3221. [PMID: 36367946 PMCID: PMC9651866 DOI: 10.1126/sciadv.add3221] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/03/2022] [Accepted: 09/22/2022] [Indexed: 06/16/2023]
Abstract
Diabetic wounds have poor healing outcomes due to the presence of numerous pathogens and a dysregulated immune response. Group B Streptococcus (GBS) is commonly isolated from diabetic wound infections, but the mechanisms of GBS virulence during these infections have not been investigated. Here, we develop a murine model of GBS diabetic wound infection and, using dual RNA sequencing, demonstrate that GBS infection triggers an inflammatory response. GBS adapts to this hyperinflammatory environment by up-regulating virulence factors including those known to be regulated by the two-component system covRS, such as the surface protein pbsP, and the cyl operon, which is responsible for hemolysin/pigmentation production. We recover hyperpigmented/hemolytic GBS colonies from the murine diabetic wound, which we determined encode mutations in covR. We further demonstrate that GBS mutants in cylE and pbsP are attenuated in the diabetic wound. This foundational study provides insight into the pathogenesis of GBS diabetic wound infections.
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Affiliation(s)
- Rebecca A. Keogh
- Department of Immunology and Microbiology, University of Colorado Anschutz, Aurora, CO, USA
| | - Amanda L. Haeberle
- Department of Immunology and Microbiology, University of Colorado Anschutz, Aurora, CO, USA
| | | | - Jeffrey S. Kavanaugh
- Department of Immunology and Microbiology, University of Colorado Anschutz, Aurora, CO, USA
| | - Eric P. Schmidt
- Department of Medicine–Pulmonary Sciences and Critical Care, University of Colorado Anschutz, Aurora, CO, USA
| | - Garrett D. Moore
- Department of Orthopedics, University of Colorado, Anschutz Medical Campus, Aurora, CO, USA
| | - Alexander R. Horswill
- Department of Immunology and Microbiology, University of Colorado Anschutz, Aurora, CO, USA
- Department of Veterans Affairs Eastern Colorado Healthcare System, Aurora, CO, USA
| | - Kelly S. Doran
- Department of Immunology and Microbiology, University of Colorado Anschutz, Aurora, CO, USA
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Henderson K, Bilancia R, Choo-Kang B, Maclay J. An Unusual Case of Postpartum Empyema. Chest 2022; 162:e157-e159. [DOI: 10.1016/j.chest.2022.05.019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2021] [Revised: 02/18/2022] [Accepted: 05/13/2022] [Indexed: 11/07/2022] Open
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Streptococcosis a Re-Emerging Disease in Aquaculture: Significance and Phytotherapy. Animals (Basel) 2022; 12:ani12182443. [PMID: 36139303 PMCID: PMC9495100 DOI: 10.3390/ani12182443] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2022] [Revised: 09/07/2022] [Accepted: 09/12/2022] [Indexed: 11/25/2022] Open
Abstract
Simple Summary Streptococcosis is an economical important bacterial disease that can seriously cause huge losses in the global aquaculture sector. In recent years studies have focused on to use extracts or essences of medicinal herbs and plants to control or treat the disease outbreaks and, in most cases the results were promising. The essential oils of the herbs or plants are more effective than the extracts and, the extracts examined have moderate efficacy in term of increasing fish survival against fish streptococcosis that could be due to the enhancement of fish immunity by the herb bio-compounds. The lack of dosage optimization, toxicity and bioavailability assays of a specific herb/plant or its bioactive compound in fish organs make it difficult to judge the validation of clinical efficacy of a particular herb/plant against fish streptococcosis, and thus, required further investigations. Abstract Streptococcosis, particularly that caused by S. iniae and S. agalactiae, is a major re-emerging bacterial disease seriously affecting the global sustainability of aquaculture development. Despite a wide spread of the disease in aquaculture, few studies have been directed at assessing the in vitro antagonistic activity and in vivo efficacy of medicinal herbs and other plants against streptococcal agents. Most in vitro studies of plant extractives against S. iniae and S. agalactiae have found antibacterial activity, but essential oils, especially those containing eugenol, carvacrol or thymol, are more effective. Although essential oils have shown better anti-streptococcal activity in in vitro assays, in vivo bioassays require more attention. The extracts examined under in vivo conditions show moderate efficacy, increasing the survival rate of infected fish, probably through the enhancement of immunity before challenge bioassays. The available data, however, lack dosage optimization, toxicity and bioavailability assays of a specific plant or its bioactive compound in fish organs; hence, it is difficult to judge the validation of clinical efficacy for the prevention or treatment of fish streptococcosis. Despite the known bioactive compounds of many tested plants, few data are available on their mode of action towards streptococcal agents. This review addresses the efficacy of medicinal plants to fish streptococcosis and discusses the current gaps.
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Ognenovska S, Mukerjee C, Sanderson-Smith M, Moore KH, Mansfield KJ. Virulence Mechanisms of Common Uropathogens and Their Intracellular Localisation within Urothelial Cells. Pathogens 2022; 11:pathogens11080926. [PMID: 36015046 PMCID: PMC9415470 DOI: 10.3390/pathogens11080926] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2022] [Revised: 08/12/2022] [Accepted: 08/15/2022] [Indexed: 11/29/2022] Open
Abstract
A recurrent urinary tract infection (UTI) is a common debilitating condition whereby uropathogens are able to survive within the urinary tract. In this study, we aimed to determine if the common uropathogens Escherichia coli, Enterococcus faecalis, and Group B Streptococcus possessed virulence mechanisms that enable the invasion of urothelial cells. Urothelial cells were isolated from women with detrusor overactivity and recurrent UTIs; the intracellular localisation of the uropathogens was determined by confocal microscopy. Uropathogens were also isolated from women with acute UTIs and their intracellular localisation and virulence mechanisms were examined (yeast agglutination, biofilm formation, and haemolysis). Fluorescent staining and imaging of urothelial cells isolated from women with refractory detrusor overactivity and recurrent UTIs demonstrated that all three uropathogens were capable of intracellular colonisation. Similarly, the bacterial isolates from women with acute UTIs were also seen to intracellularly localise using an in vitro model. All Enterococcus and Streptococcus isolates possessed a haemolytic capacity and displayed a strong biofilm formation whilst yeast cell agglutination was unique to Escherichia coli. The expression of virulence mechanisms by these uropathogenic species was observed to correlate with successful urothelial cell invasion. Invasion into the bladder urothelium was seen to be a common characteristic of uropathogens, suggesting that bacterial reservoirs within the bladder contribute to the incidence of recurrent UTIs.
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Affiliation(s)
- Samantha Ognenovska
- Detrusor Muscle Laboratory, Department of Urogynaecology, University of New South Wales, St. George Hospital, Sydney, NSW 2217, Australia
| | - Chinmoy Mukerjee
- Department of Microbiology, St. George Hospital, Sydney, NSW 2217, Australia
| | - Martina Sanderson-Smith
- Illawarra Health and Medical Research Institute, Wollongong, NSW 2522, Australia
- Molecular Horizons, University of Wollongong, Wollongong, NSW 2522, Australia
| | - Kate H. Moore
- Detrusor Muscle Laboratory, Department of Urogynaecology, University of New South Wales, St. George Hospital, Sydney, NSW 2217, Australia
| | - Kylie J. Mansfield
- Illawarra Health and Medical Research Institute, Wollongong, NSW 2522, Australia
- Graduate School of Medicine, University of Wollongong, Wollongong, NSW 2522, Australia
- Correspondence:
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22
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Akpaka PE, Henry K, Thompson R, Unakal C. Colonization of Streptococcus agalactiae among pregnant patients in Trinidad and Tobago. IJID REGIONS 2022; 3:96-100. [PMID: 35755456 PMCID: PMC9216269 DOI: 10.1016/j.ijregi.2022.03.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Revised: 03/10/2022] [Accepted: 03/12/2022] [Indexed: 11/03/2022]
Abstract
The rate of Streptococcus agalactiae [group B streptococcus (GBS)] colonization in antenatal patients is high. Molecular analysis is a useful tool for screening and detection of GBS isolates. GBS are still susceptible to commonly available antibiotics in Trinidad and Tobago. There is a need to institute routine GBS screening in antenatal patients in Trinidad and Tobago.
Objective Methods Results Conclusion
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23
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Pellegrini A, Lentini G, Famà A, Bonacorsi A, Scoffone VC, Buroni S, Trespidi G, Postiglione U, Sassera D, Manai F, Pietrocola G, Firon A, Biondo C, Teti G, Beninati C, Barbieri G. CodY Is a Global Transcriptional Regulator Required for Virulence in Group B Streptococcus. Front Microbiol 2022; 13:881549. [PMID: 35572655 PMCID: PMC9096947 DOI: 10.3389/fmicb.2022.881549] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2022] [Accepted: 03/21/2022] [Indexed: 12/03/2022] Open
Abstract
Group B Streptococcus (GBS) is a Gram-positive bacterium able to switch from a harmless commensal of healthy adults to a pathogen responsible for invasive infections in neonates. The signals and regulatory mechanisms governing this transition are still largely unknown. CodY is a highly conserved global transcriptional regulator that links nutrient availability to the regulation of major metabolic and virulence pathways in low-G+C Gram-positive bacteria. In this work, we investigated the role of CodY in BM110, a GBS strain representative of a hypervirulent lineage associated with the majority of neonatal meningitis. Deletion of codY resulted in a reduced ability of the mutant strain to cause infections in neonatal and adult animal models. The observed decreased in vivo lethality was associated with an impaired ability of the mutant to persist in the blood, spread to distant organs, and cross the blood-brain barrier. Notably, the codY null mutant showed reduced adhesion to monolayers of human epithelial cells in vitro and an increased ability to form biofilms, a phenotype associated with strains able to asymptomatically colonize the host. RNA-seq analysis showed that CodY controls about 13% of the genome of GBS, acting mainly as a repressor of genes involved in amino acid transport and metabolism and encoding surface anchored proteins, including the virulence factor Srr2. CodY activity was shown to be dependent on the availability of branched-chain amino acids, which are the universal cofactors of this regulator. These results highlight a key role for CodY in the control of GBS virulence.
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Affiliation(s)
- Angelica Pellegrini
- Department of Biology and Biotechnology "Lazzaro Spallanzani," University of Pavia, Pavia, Italy
| | - Germana Lentini
- Department of Human Pathology and Medicine, University of Messina, Messina, Italy
| | - Agata Famà
- Department of Human Pathology and Medicine, University of Messina, Messina, Italy
| | - Andrea Bonacorsi
- Department of Biology and Biotechnology "Lazzaro Spallanzani," University of Pavia, Pavia, Italy
| | - Viola Camilla Scoffone
- Department of Biology and Biotechnology "Lazzaro Spallanzani," University of Pavia, Pavia, Italy
| | - Silvia Buroni
- Department of Biology and Biotechnology "Lazzaro Spallanzani," University of Pavia, Pavia, Italy
| | - Gabriele Trespidi
- Department of Biology and Biotechnology "Lazzaro Spallanzani," University of Pavia, Pavia, Italy
| | - Umberto Postiglione
- Department of Biology and Biotechnology "Lazzaro Spallanzani," University of Pavia, Pavia, Italy
| | - Davide Sassera
- Department of Biology and Biotechnology "Lazzaro Spallanzani," University of Pavia, Pavia, Italy
| | - Federico Manai
- Department of Biology and Biotechnology "Lazzaro Spallanzani," University of Pavia, Pavia, Italy
| | | | - Arnaud Firon
- Institut Pasteur, Université de Paris, CNRS UMR 6047, Unité Biologie des Bactéries Pathogènes à Gram-positif, Paris, France
| | - Carmelo Biondo
- Department of Human Pathology and Medicine, University of Messina, Messina, Italy
| | | | - Concetta Beninati
- Department of Human Pathology and Medicine, University of Messina, Messina, Italy
| | - Giulia Barbieri
- Department of Biology and Biotechnology "Lazzaro Spallanzani," University of Pavia, Pavia, Italy
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Dobrut A, Ochońska D, Brzozowska E, Górska S, Kaszuba-Zwoinska J, Gołda-Cępa M, Gamian A, Brzychczy-Wloch M. Molecular Characteristic, Antibiotic Resistance, and Detection of Highly Immunoreactive Proteins of Group B Streptococcus Strains Isolated From Urinary Tract Infections in Polish Adults. Front Microbiol 2022; 13:809724. [PMID: 35391726 PMCID: PMC8981152 DOI: 10.3389/fmicb.2022.809724] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2021] [Accepted: 01/21/2022] [Indexed: 12/02/2022] Open
Abstract
Group B streptococcus (GBS) is one of the uropathogens that causes urinary tract infections (UTIs). The aims of this article were molecular characterization, an analysis of antimicrobial susceptibility profiles, adherence to bladder endothelial cells, and the detection of immunoreactive proteins of 94 clinical strains of GBS isolated from adult Polish patients with UTI. Antibiotic susceptibilities were determined by disk diffusion. Serotyping and Alp family genes detection were studied using multiplex PCR. Genetic profiles were determined by pulsed-field gel electrophoresis. The adherence ability of the studied strains was estimated by incubation on human bladder microvascular endothelial cell line. Immunoreactive proteins were studied by immunoblotting. Antibiotic susceptibility investigation revealed that 22% of GBS strains were resistant to erythromycin, whereas 18% demonstrated resistance to clindamycin. cMLSB was present in 76% of the resistant strains, M phenotype was detected in 14%, whereas iMLSB was present for 10%. The most common serotype was serotype III (31%), followed by serotype V (27%), and serotype Ia (17%). The genes that dominated among other Alp genes were: epsilon (29%), alp2 (27%), and rib (23%). The most common co-occurring serotypes and Alp genes were: Ia and epsilon, III and rib, III and alp2, V and alp2, and V and alp3 (p < 0.001). The PFGE method showed high clonality for serotype V and cMLSB (p < 001). The PFGE method showed high clonality for serotype V. Furthermore, this serotype was significantly associated with the cMLSB phenotype (p < 0.001). The most common immunoreactive proteins demonstrated masses of 50 kDa and 45–47 kDa. Although examined GBS isolates showed high genetic diversity, immunoreactive proteins were common for most of the studied GBS isolates, which may indicate their conservation, and allows to consider them as potential immunodiagnostic markers. Although the examined GBS isolates showed high genetic diversity, immunoreactive proteins were shared by most of the studied GBS isolates. It may indicate their conservation, thus allowing to consider them as potential immunodiagnostic markers.
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Affiliation(s)
- Anna Dobrut
- Department of Molecular Medical Microbiology, Chair of Microbiology, Faculty of Medicine, Jagiellonian University Medical College, Kraków, Poland
| | - Dorota Ochońska
- Department of Molecular Medical Microbiology, Chair of Microbiology, Faculty of Medicine, Jagiellonian University Medical College, Kraków, Poland
| | - Ewa Brzozowska
- Laboratory of Medical Microbiology, Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Wrocław, Poland
| | - Sabina Górska
- Laboratory of Microbiome Immunobiology, Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Wrocław, Poland
| | - Jolanta Kaszuba-Zwoinska
- Chair of Pathophysiology, Faculty of Medicine, Jagiellonian University Medical College, Kraków, Poland
| | | | - Andrzej Gamian
- Laboratory of Medical Microbiology, Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Wrocław, Poland
| | - Monika Brzychczy-Wloch
- Department of Molecular Medical Microbiology, Chair of Microbiology, Faculty of Medicine, Jagiellonian University Medical College, Kraków, Poland
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Palacios-Saucedo GDC, Rivera-Morales LG, Vázquez-Guillén JM, Caballero-Trejo A, Mellado-García MC, Flores-Flores AS, González-Navarro JA, Herrera-Rivera CG, Osuna-Rosales LE, Hernández-González JA, Vázquez-Juárez R, Barrón-Enríquez C, Valladares-Trujillo R, Treviño-Baez JD, Alonso-Téllez CA, Ramírez-Calvillo LD, Cerda-Flores RM, Ortiz-López R, Rivera-Alvarado MÁ, Solórzano-Santos F, Castro-Garza J, Rodríguez-Padilla C. Genomic analysis of virulence factors and antimicrobial resistance of group B Streptococcus isolated from pregnant women in northeastern Mexico. PLoS One 2022; 17:e0264273. [PMID: 35294459 PMCID: PMC8926241 DOI: 10.1371/journal.pone.0264273] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Accepted: 02/08/2022] [Indexed: 11/18/2022] Open
Abstract
Introduction
Group B Streptococcus (GBS) causes infections in women during pregnancy and puerperium and invasive infections in newborns. The genes lmb, cylE, scpB, and hvgA are involved with increased virulence of GBS, and hypervirulent clones have been identified in different regions. In addition, increasing resistance of GBS to macrolides and lincosamides has been reported, so knowing the patterns of antibiotic resistance may be necessary to prevent and treat GBS infections. This study aimed to identify virulence genes and antibiotic resistance associated with GBS colonization in pregnant women from northeastern Mexico.
Methods
Pregnant women with 35–37 weeks of gestation underwent recto-vaginal swabbing. One swab was inoculated into Todd-Hewitt broth supplemented with gentamicin and nalidixic acid, a second swab was inoculated into LIM enrichment broth, and a third swab was submerged into a transport medium. All samples were subcultured onto blood agar. After overnight incubation, suggestive colonies with or without hemolysis were analyzed to confirm GBS identification by Gram staining, catalase test, hippurate hydrolysis, CAMP test, and incubation in a chromogenic medium. We used latex agglutination to confirm and serotype GBS isolates. Antibiotic resistance patterns were assessed by Vitek 2 and disk diffusion. Periumbilical, rectal and nasopharyngeal swabs were collected from some newborns of colonized mothers. All colonized women and their newborns were followed up for three months to assess the development of disease attributable to GBS. Draft genomes of all GBS isolates were obtained by whole-genome sequencing. In addition, bioinformatic analysis to identify genes encoding capsular polysaccharides and virulence factors was performed using BRIG, while antibiotic resistance genes were identified using the CARD database.
Results
We found 17 GBS colonized women out of 1154 pregnant women (1.47%). None of the six newborns sampled were colonized, and no complications due to GBS were detected in pregnant women or newborns. Three isolates were serotype I, 5 serotype II, 3 serotype III, 4 serotype IV, and 2 serotype V. Ten distinct virulence gene profiles were identified, being scpB, lmb, fbsA, acp, PI-1, PI-2a, cylE the most common (3/14, 21%). The virulence genes identified were scpB, lmb, cylE, PI-1, fbsA, PI-2a, acp, fbsB, PI-2b, and hvgA. We identified resistance to tetracycline in 65% (11/17) of the isolates, intermediate susceptibility to clindamycin in 41% (7/17), and reduced susceptibility to ampicillin in 23.5% (4/17). The tetM gene associated to tetracyclines resistance was found in 79% (11/14) and the mel and mefA genes associated to macrolides resistance in 7% (1/14).
Conclusions
The low prevalence of colonization and the non-occurrence of mother-to-child transmission suggest that the intentional search for GBS colonization in this population is not justified. Our results also suggest that risk factors should guide the use of intrapartum antibiotic prophylaxis. The detection of strains with genes coding virulence factors means that clones with pathogenic potential circulates in this region. On the other hand, the identification of decreased susceptibility to antibiotics from different antimicrobial categories shows the importance of adequately knowing the resistance patterns to prevent and to treat GBS perinatal infection.
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Affiliation(s)
- Gerardo del Carmen Palacios-Saucedo
- División de Investigación en Salud y División de Auxiliares de Diagnóstico, Unidad Médica de Alta Especialidad Hospital de Especialidades No. 25, Instituto Mexicano del Seguro Social, Monterrey, Nuevo León, México
| | - Lydia Guadalupe Rivera-Morales
- Laboratorio de Inmunología y Virología, Facultad de Ciencias Biológicas, Universidad Autónoma de Nuevo León, San Nicolás de los Garza, Nuevo León, México
- * E-mail:
| | - José Manuel Vázquez-Guillén
- Laboratorio de Inmunología y Virología, Facultad de Ciencias Biológicas, Universidad Autónoma de Nuevo León, San Nicolás de los Garza, Nuevo León, México
| | - Amilcar Caballero-Trejo
- Departamento de Epidemiología y Dirección de Educación e Investigación, Unidad Médica de Alta Especialidad No. 23 Hospital de Ginecología y Obstetricia “Dr. Ignacio Morones Prieto”, Instituto Mexicano del Seguro Social, Monterrey, Nuevo León, México
| | - Melissa Carolina Mellado-García
- Laboratorio de Inmunología y Virología, Facultad de Ciencias Biológicas, Universidad Autónoma de Nuevo León, San Nicolás de los Garza, Nuevo León, México
| | - Aldo Sebastián Flores-Flores
- Laboratorio de Inmunología y Virología, Facultad de Ciencias Biológicas, Universidad Autónoma de Nuevo León, San Nicolás de los Garza, Nuevo León, México
| | - José Alfredo González-Navarro
- Laboratorio de Inmunología y Virología, Facultad de Ciencias Biológicas, Universidad Autónoma de Nuevo León, San Nicolás de los Garza, Nuevo León, México
| | - Celia Geovana Herrera-Rivera
- Dirección General de Calidad y Educación en Salud, Secretaría de Salud, Alcaldía Miguel Hidalgo, Ciudad de México, México
| | - Luis Ernesto Osuna-Rosales
- Unidad de Genómica, Centro de Investigación y Desarrollo en Ciencias de la Salud, Universidad Autónoma de Nuevo León, Monterrey, Nuevo León, México
| | - Julio Antonio Hernández-González
- Laboratorio de Genómica y Bioinformática, Centro de Investigaciones Biológicas del Noroeste, La Paz, Baja California Sur, México
| | - Ricardo Vázquez-Juárez
- Laboratorio de Genómica y Bioinformática, Centro de Investigaciones Biológicas del Noroeste, La Paz, Baja California Sur, México
| | - Carolina Barrón-Enríquez
- Laboratorio de Inmunología y Virología, Facultad de Ciencias Biológicas, Universidad Autónoma de Nuevo León, San Nicolás de los Garza, Nuevo León, México
| | - Ramón Valladares-Trujillo
- Coordinación de Educación e Investigación en Salud, Hospital General de Zona No. 17, Instituto Mexicano del Seguro Social, Monterrey, Nuevo León, México
| | - Joaquín Dario Treviño-Baez
- Departamento de Epidemiología y Dirección de Educación e Investigación, Unidad Médica de Alta Especialidad No. 23 Hospital de Ginecología y Obstetricia “Dr. Ignacio Morones Prieto”, Instituto Mexicano del Seguro Social, Monterrey, Nuevo León, México
| | - César Alejandro Alonso-Téllez
- Dirección General de Calidad y Educación en Salud, Secretaría de Salud, Alcaldía Miguel Hidalgo, Ciudad de México, México
| | - Luis Daniel Ramírez-Calvillo
- Dirección General de Calidad y Educación en Salud, Secretaría de Salud, Alcaldía Miguel Hidalgo, Ciudad de México, México
| | | | - Rocío Ortiz-López
- Unidad de Genómica, Centro de Investigación y Desarrollo en Ciencias de la Salud, Universidad Autónoma de Nuevo León, Monterrey, Nuevo León, México
| | - Miguel Ángel Rivera-Alvarado
- División de Investigación en Salud y División de Auxiliares de Diagnóstico, Unidad Médica de Alta Especialidad Hospital de Especialidades No. 25, Instituto Mexicano del Seguro Social, Monterrey, Nuevo León, México
| | - Fortino Solórzano-Santos
- Hospital de Pediatría, Centro Médico Nacional Siglo XXI, Instituto Mexicano del Seguro Social, Alcaldía Cuauhtémoc, Ciudad de México, México
| | - Jorge Castro-Garza
- Laboratorio de Bioquímica y Genética de Microorganismos, Facultad de Ciencias Biológicas, Universidad Autónoma de Nuevo León, San Nicolás de los Garza, Nuevo León, México
| | - Cristina Rodríguez-Padilla
- Laboratorio de Inmunología y Virología, Facultad de Ciencias Biológicas, Universidad Autónoma de Nuevo León, San Nicolás de los Garza, Nuevo León, México
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26
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Furuta A, Brokaw A, Manuel G, Dacanay M, Marcell L, Seepersaud R, Rajagopal L, Adams Waldorf K. Bacterial and Host Determinants of Group B Streptococcal Infection of the Neonate and Infant. Front Microbiol 2022; 13:820365. [PMID: 35265059 PMCID: PMC8899651 DOI: 10.3389/fmicb.2022.820365] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2021] [Accepted: 01/27/2022] [Indexed: 12/15/2022] Open
Abstract
Group B streptococci (GBS) are Gram-positive β-hemolytic bacteria that can cause serious and life-threatening infections in neonates manifesting as sepsis, pneumonia, meningitis, osteomyelitis, and/or septic arthritis. Invasive GBS infections in neonates in the first week of life are referred to as early-onset disease (EOD) and thought to be acquired by the fetus through exposure to GBS in utero or to vaginal fluids during birth. Late-onset disease (LOD) refers to invasive GBS infections between 7 and 89 days of life. LOD transmission routes are incompletely understood, but may include breast milk, household contacts, nosocomial, or community sources. Invasive GBS infections and particularly meningitis may result in significant neurodevelopmental injury and long-term disability that persists into childhood and adulthood. Globally, EOD and LOD occur in more than 300,000 neonates and infants annually, resulting in 90,000 infant deaths and leaving more than 10,000 infants with a lifelong disability. In this review, we discuss the clinical impact of invasive GBS neonatal infections and then summarize virulence and host factors that allow the bacteria to exploit the developing neonatal immune system and target organs. Specifically, we consider the mechanisms known to enable GBS invasion into the neonatal lung, blood vessels and brain. Understanding mechanisms of GBS invasion and pathogenesis relevant to infections in the neonate and infant may inform the development of therapeutics to prevent or mitigate injury, as well as improve risk stratification.
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Affiliation(s)
- Anna Furuta
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Seattle, WA, United States.,Department of Global Health, University of Washington, Seattle, WA, United States
| | - Alyssa Brokaw
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Seattle, WA, United States.,Department of Global Health, University of Washington, Seattle, WA, United States
| | - Gygeria Manuel
- Morehouse School of Medicine, Atlanta, GA, United States
| | - Matthew Dacanay
- Department of Obstetrics & Gynecology, University of Washington, Seattle, WA, United States
| | - Lauren Marcell
- Department of Obstetrics & Gynecology, University of Washington, Seattle, WA, United States
| | - Ravin Seepersaud
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Seattle, WA, United States
| | - Lakshmi Rajagopal
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Seattle, WA, United States.,Department of Global Health, University of Washington, Seattle, WA, United States.,Department of Pediatrics, University of Washington, Seattle, WA, United States
| | - Kristina Adams Waldorf
- Department of Global Health, University of Washington, Seattle, WA, United States.,Department of Obstetrics & Gynecology, University of Washington, Seattle, WA, United States.,Department of Obstetrics and Gynecology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
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27
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Moore RE, Thomas HC, Manning SD, Gaddy JA, Townsend SD. Galacto-Oligosaccharide Supplementation Modulates Pathogen-Commensal Competition between Streptococcus agalactiae and Streptococcus salivarius. Chembiochem 2022; 23:e202100559. [PMID: 34788501 PMCID: PMC9197176 DOI: 10.1002/cbic.202100559] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Revised: 11/16/2021] [Indexed: 02/06/2023]
Abstract
The members of the infant microbiome are governed by feeding method (breastmilk vs. formula). Regardless of the source of nutrition, a competitive growth advantage can be provided to commensals through prebiotics - either human milk oligosaccharides (HMOs) or plant oligosaccharides that are supplemented into formula. To characterize how prebiotics modulate commensal - pathogen interactions, we have designed and studied a minimal microbiome where a pathogen, Streptococcus agalactiae engages with a commensal, Streptococcus salivarius. We discovered that while S. agalactiae suppresses the growth of S. salivarius via increased lactic acid production, galacto-oligosaccharides (GOS) supplementation reverses the effect. This result has major implications in characterizing how single species survive in the gut, what niche they occupy, and how they engage with other community members.
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Affiliation(s)
- Rebecca E. Moore
- Department of Chemistry, Vanderbilt University, Nashville, Tennessee 37235, United States
| | - Harrison C. Thomas
- Department of Chemistry, Vanderbilt University, Nashville, Tennessee 37235, United States,Vanderbilt University School of Medicine, Nashville, Tennessee 37212, United States
| | - Shannon D. Manning
- Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, Michigan 48824 United States
| | - Jennifer A. Gaddy
- Tennessee Valley Healthcare Systems, Department of Veterans Affairs, Nashville, Tennessee 37212, United States,Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee 37232, United States,
| | - Steven D. Townsend
- Department of Chemistry, Vanderbilt University, Nashville, Tennessee 37235, United States,Corresponding Authors
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28
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Francis JD, Guevara MA, Lu J, Madhi SA, Kwatra G, Aronoff DM, Manning SD, Gaddy JA. The antimicrobial activity of zinc against group B Streptococcus is strain-dependent across diverse sequence types, capsular serotypes, and invasive versus colonizing isolates. BMC Microbiol 2022; 22:23. [PMID: 35026981 PMCID: PMC8756620 DOI: 10.1186/s12866-021-02428-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2021] [Accepted: 12/13/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Streptococcus agalactiae or Group B Streptococcus (GBS) is an encapsulated gram-positive bacterial pathobiont that commonly colonizes the lower gastrointestinal tract and reproductive tract of human hosts. This bacterium can infect the gravid reproductive tract and cause invasive infections of pregnant patients and neonates. Upon colonizing the reproductive tract, the bacterial cell is presented with numerous nutritional challenges imposed by the host. One strategy employed by the host innate immune system is intoxication of bacterial invaders with certain transition metals such as zinc. METHODOLOGY Previous work has demonstrated that GBS must employ elegant strategies to circumnavigate zinc stress in order to survive in the vertebrate host. We assessed 30 strains of GBS from diverse isolation sources, capsular serotypes, and sequence types for susceptibility or resistance to zinc intoxication. RESULTS Invasive strains, such as those isolated from early onset disease manifestations of GBS infection were significantly less susceptible to zinc toxicity than colonizing strains isolated from rectovaginal swabs of pregnant patients. Additionally, capsular type III (cpsIII) strains and the ST-17 and ST-19 strains exhibited the greatest resilience to zinc stress, whereas ST-1 and ST-12 strains as well as those possessing capsular type Ib (cpsIb) were more sensitive to zinc intoxication. Thus, this study demonstrates that the transition metal zinc possesses antimicrobial properties against a wide range of GBS strains, with isolation source, capsular serotype, and sequence type contributing to susceptibility or resistance to zinc stress.
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Affiliation(s)
- Jamisha D Francis
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, TN, 37212, USA
| | - Miriam A Guevara
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, TN, 37212, USA
| | - Jacky Lu
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, TN, 37212, USA
| | - Shabir A Madhi
- South African Medical Research Council Vaccines and Infectious Diseases Analytics Research Unit, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Gaurav Kwatra
- South African Medical Research Council Vaccines and Infectious Diseases Analytics Research Unit, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
- Department of Clinical Microbiology, Christian Medical College, Vellore, India
| | - David M Aronoff
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, TN, 37212, USA
- Department of Medicine, Division of Infectious Diseases, Vanderbilt University Medical Center, A2200 Medical Center North, 1161 21st Avenue South, Nashville, TN, 37232, U.S.A
- Department of Obstetrics and Gynecology, Vanderbilt University Medical Center Nashville, Nashville, TN, 37232, USA
| | - Shannon D Manning
- Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, MI, 48824, USA
| | - Jennifer A Gaddy
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, TN, 37212, USA.
- Department of Medicine, Division of Infectious Diseases, Vanderbilt University Medical Center, A2200 Medical Center North, 1161 21st Avenue South, Nashville, TN, 37232, U.S.A..
- Department of Veterans Affairs, Tennessee Valley Healthcare Systems, Nashville, TN, 37212, USA.
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Liang M, Gong W, Sun C, Zhao J, Wang H, Chen Z, Xiao M, Gu G. Sequential One‐pot Three‐enzyme Synthesis of the Tetrasaccha‐ride Repeating Unit of Group B Streptococcus Serotype
VIII
Capsular Polysaccharide. CHINESE J CHEM 2021. [DOI: 10.1002/cjoc.202100822] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Min Liang
- National Glycoengineering Research Center, Shandong Provincial Key Laboratory of Carbohydrate Chemistry and Glycobiology, Shandong University 72 Binhai Road Qingdao 266237 China
- NMPA Key Laboratory for Quality Research and Evaluation of Carbohydrate‐based Medicine, Shandong University Qingdao 266237 China
| | - Wei Gong
- National Glycoengineering Research Center, Shandong Provincial Key Laboratory of Carbohydrate Chemistry and Glycobiology, Shandong University 72 Binhai Road Qingdao 266237 China
- School of Pharmaceutical Science, Shandong University 44 West Wenhua Road Jinan 25012 China
| | - Chongzhen Sun
- National Glycoengineering Research Center, Shandong Provincial Key Laboratory of Carbohydrate Chemistry and Glycobiology, Shandong University 72 Binhai Road Qingdao 266237 China
- NMPA Key Laboratory for Quality Research and Evaluation of Carbohydrate‐based Medicine, Shandong University Qingdao 266237 China
| | - Jielin Zhao
- National Glycoengineering Research Center, Shandong Provincial Key Laboratory of Carbohydrate Chemistry and Glycobiology, Shandong University 72 Binhai Road Qingdao 266237 China
- NMPA Key Laboratory for Quality Research and Evaluation of Carbohydrate‐based Medicine, Shandong University Qingdao 266237 China
| | - Hong Wang
- National Glycoengineering Research Center, Shandong Provincial Key Laboratory of Carbohydrate Chemistry and Glycobiology, Shandong University 72 Binhai Road Qingdao 266237 China
- NMPA Key Laboratory for Quality Research and Evaluation of Carbohydrate‐based Medicine, Shandong University Qingdao 266237 China
| | - Zonggang Chen
- National Glycoengineering Research Center, Shandong Provincial Key Laboratory of Carbohydrate Chemistry and Glycobiology, Shandong University 72 Binhai Road Qingdao 266237 China
- NMPA Key Laboratory for Quality Research and Evaluation of Carbohydrate‐based Medicine, Shandong University Qingdao 266237 China
| | - Min Xiao
- National Glycoengineering Research Center, Shandong Provincial Key Laboratory of Carbohydrate Chemistry and Glycobiology, Shandong University 72 Binhai Road Qingdao 266237 China
- NMPA Key Laboratory for Quality Research and Evaluation of Carbohydrate‐based Medicine, Shandong University Qingdao 266237 China
| | - Guofeng Gu
- National Glycoengineering Research Center, Shandong Provincial Key Laboratory of Carbohydrate Chemistry and Glycobiology, Shandong University 72 Binhai Road Qingdao 266237 China
- NMPA Key Laboratory for Quality Research and Evaluation of Carbohydrate‐based Medicine, Shandong University Qingdao 266237 China
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30
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Maternal vaccination with a type-III glycoconjugate protects mouse neonates against Group B Streptococcus intranasal infection. Sci Rep 2021; 11:21384. [PMID: 34725414 PMCID: PMC8560876 DOI: 10.1038/s41598-021-00941-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Accepted: 10/12/2021] [Indexed: 11/15/2022] Open
Abstract
Group B Streptococcus (GBS) is generally an asymptomatic colonizer of human mucosa but it occasionally infects pregnant women and neonates through vertical transmission, causing disease during the first weeks of life with frequent and severe complications. Preclinical studies have shown that maternal vaccination with polysaccharide-based vaccines protects mothers and offspring from GBS mucosal colonization and consecutive infection. In these models, bacteria were inoculated in mouse either intravaginally in the last trimester of pregnancy or systemically in pups. Here, we investigated whether maternal vaccination with glycoconjugate vaccines may also prevent GBS-mediated colonization and disease in neonates using an infection route that more closely mimics inhalation or ingestion of bacteria during human delivery. To address this point, mice aged less than two days were intranasally challenged with epidemiologically relevant GBS strains. Bacteria were found to colonize nose and intestine, reaching in some cases lungs and blood during the first days of life. Bacteria were also found in vagina of a fraction of colonized female mice within the first month of life. GBS-specific IgG induced by maternal vaccination with a glycoconjugate vaccine formulation were found in blood and mucosal tissues of newborns. Finally, when intranasally challenged with GBS serotype III strains, pups delivered by vaccinated mothers were partially protected against mucosal colonization and deeper infection.
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31
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Cho H, Masters T, Greenwood‐Quaintance KE, Johnson S, Jeraldo PR, Chia N, Pu M, Abdel MP, Patel R. Transcriptomic analysis of Streptococcus agalactiae periprosthetic joint infection. Microbiologyopen 2021; 10:e1256. [PMID: 34964296 PMCID: PMC8678771 DOI: 10.1002/mbo3.1256] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2021] [Revised: 09/09/2021] [Accepted: 11/22/2021] [Indexed: 11/08/2022] Open
Abstract
Although Streptococcus agalactiae periprosthetic joint infection (PJI) is not as prevalent as staphylococcal PJI, invasive S. agalactiae infection is not uncommon. Here, RNA-seq was used to perform transcriptomic analysis of S. agalactiae PJI using fluid derived from sonication of explanted arthroplasties of subjects with S. agalactiae PJI, with results compared to those of S. agalactiae strain NEM316 grown in vitro. A total of 227 genes with outlier expression were found (164 upregulated and 63 downregulated) between PJI sonicate fluid and in vitro conditions. Functional enrichment analysis showed genes involved in mobilome and inorganic ion transport and metabolism to be most enriched. Genes involved in nickel, copper, and zinc transport, were upregulated. Among known virulence factors, cyl operon genes, encoding β-hemolysin/cytolysin, were consistently highly expressed in PJI versus in vitro. The data presented provide insight into S. agalactiae PJI pathogenesis and may be a resource for identification of novel PJI therapeutics or vaccines against invasive S. agalactiae infections.
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Affiliation(s)
- Hye‐Kyung Cho
- Division of Clinical Microbiology, Department of Laboratory Medicine and PathologyMayo ClinicRochesterMinnesotaUSA
| | - Thao Masters
- Division of Clinical Microbiology, Department of Laboratory Medicine and PathologyMayo ClinicRochesterMinnesotaUSA
| | | | - Stephen Johnson
- Department of Health Sciences ResearchMayo ClinicRochesterMinnesotaUSA
| | - Patricio R. Jeraldo
- Center for Individualized MedicineMayo ClinicRochesterMinnesotaUSA
- Department of SurgeryMayo ClinicRochesterMinnesotaUSA
| | - Nicholas Chia
- Center for Individualized MedicineMayo ClinicRochesterMinnesotaUSA
- Department of SurgeryMayo ClinicRochesterMinnesotaUSA
| | - Meng Pu
- Department of Medicine, Division of Gastroenterology and HepatologyMayo ClinicRochesterMinnesotaUSA
| | - Matthew P. Abdel
- Department of Orthopedic SurgeryMayo ClinicRochesterMinnesotaUSA
| | - Robin Patel
- Division of Clinical Microbiology, Department of Laboratory Medicine and PathologyMayo ClinicRochesterMinnesotaUSA
- Division of Infectious Diseases, Department of MedicineMayo ClinicRochesterMinnesotaUSA
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32
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Kabelitz T, Aubry E, van Vorst K, Amon T, Fulde M. The Role of Streptococcus spp. in Bovine Mastitis. Microorganisms 2021; 9:1497. [PMID: 34361932 PMCID: PMC8305581 DOI: 10.3390/microorganisms9071497] [Citation(s) in RCA: 47] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Revised: 06/30/2021] [Accepted: 07/07/2021] [Indexed: 11/18/2022] Open
Abstract
The Streptococcus genus belongs to one of the major pathogen groups inducing bovine mastitis. In the dairy industry, mastitis is the most common and costly disease. It not only negatively impacts economic profit due to milk losses and therapy costs, but it is an important animal health and welfare issue as well. This review describes a classification, reservoirs, and frequencies of the most relevant Streptococcus species inducing bovine mastitis (S. agalactiae, S. dysgalactiae and S. uberis). Host and environmental factors influencing mastitis susceptibility and infection rates will be discussed, because it has been indicated that Streptococcus herd prevalence is much higher than mastitis rates. After infection, we report the sequence of cow immune reactions and differences in virulence factors of the main Streptococcus species. Different mastitis detection techniques together with possible conventional and alternative therapies are described. The standard approach treating streptococcal mastitis is the application of ß-lactam antibiotics. In streptococci, increased antimicrobial resistance rates were identified against enrofloxacin, tetracycline, and erythromycin. At the end, control and prevention measures will be considered, including vaccination, hygiene plan, and further interventions. It is the aim of this review to estimate the contribution and to provide detailed knowledge about the role of the Streptococcus genus in bovine mastitis.
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Affiliation(s)
- Tina Kabelitz
- Department of Engineering for Livestock Management, Leibniz Institute for Agricultural Engineering and Bioeconomy e.V. (ATB), Max-Eyth-Allee 100, 14469 Potsdam, Germany;
| | - Etienne Aubry
- Department of Veterinary Medicine, Institute of Microbiology and Epizootics, Freie Universität Berlin, Robert-von-Ostertag-Str. 7-13, 14163 Berlin, Germany; (E.A.); (K.v.V.); (M.F.)
| | - Kira van Vorst
- Department of Veterinary Medicine, Institute of Microbiology and Epizootics, Freie Universität Berlin, Robert-von-Ostertag-Str. 7-13, 14163 Berlin, Germany; (E.A.); (K.v.V.); (M.F.)
| | - Thomas Amon
- Department of Engineering for Livestock Management, Leibniz Institute for Agricultural Engineering and Bioeconomy e.V. (ATB), Max-Eyth-Allee 100, 14469 Potsdam, Germany;
- Department of Veterinary Medicine, Institute for Animal Hygiene and Environmental Health, Freie Universität Berlin, Robert-von-Ostertag-Str. 7-13, 14163 Berlin, Germany
| | - Marcus Fulde
- Department of Veterinary Medicine, Institute of Microbiology and Epizootics, Freie Universität Berlin, Robert-von-Ostertag-Str. 7-13, 14163 Berlin, Germany; (E.A.); (K.v.V.); (M.F.)
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33
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Liu G, Gao T, Yao H, Liu Y, Lu C. Transcriptional regulator XtgS is involved in iron transition and attenuates the virulence of Streptococcus agalactiae. Res Vet Sci 2021; 138:109-115. [PMID: 34126449 DOI: 10.1016/j.rvsc.2021.06.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2021] [Revised: 05/21/2021] [Accepted: 06/07/2021] [Indexed: 10/21/2022]
Abstract
Streptococcus agalactiae (GBS) is an important pathogen that has increasingly received attention for its role in invasive infections and its broad host range. Research on the regulation of gene expression could illuminate GBS pathogenesis. We previously identified a novel transcriptional regulator XtgS, which is a negative regulator of GBS pathogenicity. Here, we demonstrate that XtgS overexpression significantly attenuated GBS virulence in zebrafish infection tests, and XtgS indirectly downregulated the transcription of two iron transport systems based on the results of transcriptomic analysis, electrophoretic mobility shift assays (EMSAs) and lacZ fusion assays. Subsequent studies verified that the inactivation of iron transport system 1 resulted in GBS excessive iron accumulation and attenuated virulence. Thus, we infer that the downregulation of iron transport system 1 caused by XtgS overexpression probably attenuates bacterial virulence, which partially clarifies the mechanism by which XtgS alleviates the pathogenesis. These findings provide new insights into the relationship between exogenous transcriptional regulation and bacterial virulence.
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Affiliation(s)
- Guangjin Liu
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China; OIE Reference Laboratory for Swine Streptococcosis, Nanjing, China; MOE Joint International Research Laboratory of Animal Health and Food Safety, Nanjing, China; Key Laboratory of Animal Bacteriology, Ministry of Agriculture, Nanjing, China.
| | - Tingting Gao
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China; OIE Reference Laboratory for Swine Streptococcosis, Nanjing, China; MOE Joint International Research Laboratory of Animal Health and Food Safety, Nanjing, China; Key Laboratory of Animal Bacteriology, Ministry of Agriculture, Nanjing, China
| | - Huochun Yao
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China; OIE Reference Laboratory for Swine Streptococcosis, Nanjing, China; MOE Joint International Research Laboratory of Animal Health and Food Safety, Nanjing, China; Key Laboratory of Animal Bacteriology, Ministry of Agriculture, Nanjing, China
| | - Yongjie Liu
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China; OIE Reference Laboratory for Swine Streptococcosis, Nanjing, China; MOE Joint International Research Laboratory of Animal Health and Food Safety, Nanjing, China; Key Laboratory of Animal Bacteriology, Ministry of Agriculture, Nanjing, China
| | - Chengping Lu
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China; OIE Reference Laboratory for Swine Streptococcosis, Nanjing, China; MOE Joint International Research Laboratory of Animal Health and Food Safety, Nanjing, China; Key Laboratory of Animal Bacteriology, Ministry of Agriculture, Nanjing, China
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34
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Research Advances on Tilapia Streptococcosis. Pathogens 2021; 10:pathogens10050558. [PMID: 34066313 PMCID: PMC8148123 DOI: 10.3390/pathogens10050558] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Revised: 03/14/2021] [Accepted: 03/17/2021] [Indexed: 12/14/2022] Open
Abstract
Streptococcus agalactiae, often referred to as group B streptococci (GBS), is a severe pathogen that can infect humans as well as other animals, including tilapia, which is extremely popular in commercial aquaculture. This pathogen causes enormous pecuniary loss, and typical symptoms of streptococcosis—the disease caused by S. agalactiae—include abnormal behavior, exophthalmos, and meningitis, among others. Multiple studies have examined virulence factors associated with S. agalactiae infection, and vaccines were explored, including studies of subunit vaccines. Known virulence factors include capsular polysaccharide (CPS), hemolysin, Christie-Atkins-Munch-Peterson (CAMP) factor, hyaluronidase (HAase), superoxide dismutase (SOD), and serine-threonine protein kinase (STPK), and effective vaccine antigens reported to date include GapA, Sip, OCT, PGK, FbsA, and EF-Tu. In this review, I summarize findings from several studies about the etiology, pathology, virulence factors, and vaccine prospects for S. agalactiae. I end by considering which research areas are likely to yield success in the prevention and treatment of tilapia streptococcosis.
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35
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Manna T, Misra AK. Synthesis of the sialylated pentasaccharide repeating unit of the capsular polysaccharide of Streptococcus group B type VI. Carbohydr Res 2021; 502:108294. [PMID: 33765475 DOI: 10.1016/j.carres.2021.108294] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Revised: 03/10/2021] [Accepted: 03/10/2021] [Indexed: 10/21/2022]
Abstract
An efficient synthetic strategy has been developed for the synthesis of the sialic acid containing pentasaccharide repeating unit of the cell wall O-antigen of Streptococcus group B type VI strain involving stereoselective α-glycosylation of sialic acid thioglycoside derivative. Stereoselective glycosylation of glycosyl trichloroacetimidate derivatives and thioglycosides were carried out using perchloric acid supported over silica (HClO4-SiO2) as a solid acid catalyst. A panel of sialic acid donors has been screened for achieving satisfactory yield and stereochemical outcome of the glycosylation reaction.
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Affiliation(s)
- Tapasi Manna
- Bose Institute, Division of Molecular Medicine, P-1/12, C.I.T. Scheme VII-M, Kolkata, 700054, India
| | - Anup Kumar Misra
- Bose Institute, Division of Molecular Medicine, P-1/12, C.I.T. Scheme VII-M, Kolkata, 700054, India.
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36
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Jusuf S, Dong PT, Hui J, Ulloa ER, Liu GY, Cheng JX. Granadaene Photobleaching Reduces the Virulence and Increases Antimicrobial Susceptibility of Streptococcus agalactiae. Photochem Photobiol 2021; 97:816-825. [PMID: 33502005 DOI: 10.1111/php.13389] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2020] [Accepted: 01/20/2021] [Indexed: 12/14/2022]
Abstract
Streptococcus agalactiae, also known as Group B Streptococcus (GBS), is increasingly recognized as a major cause of soft tissue and invasive diseases in the elderly and diabetic populations. Antibiotics like penicillin are used with great frequency to treat these infections, although antimicrobial resistance is increasing among GBS strains and underlines a need for alternative methods not reliant on traditional antibiotics. GBS granadaene pigment is related to the hemolysin/cytolysin of GBS, which is critical for the pathogenesis of GBS diseases. Here, we show that photobleaching granadaene dampens the hemolytic activity of GBS. Furthermore, photobleaching of this antioxidant was found to increase GBS susceptibility to killing by reactive oxygen species like hydrogen peroxide. Treatment with light was also shown to affect GBS membrane permeability and contribute to increased susceptibility to the cell membrane-targeting antibiotic daptomycin. Overall, our study demonstrates dual effects of photobleaching on the virulence and antimicrobial susceptibility of GBS and suggests a novel approach for the treatment of GBS infection.
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Affiliation(s)
- Sebastian Jusuf
- Department of Biomedical Engineering, Boston University, Boston, MA
| | - Pu-Ting Dong
- Department of Chemistry, Boston University, Boston, MA
| | - Jie Hui
- Department of Electrical & Computer Engineering, Boston University, Boston, MA
| | - Erlinda R Ulloa
- Department of Pediatrics, University of California Irvine School of Medicine, Irvine, CA
| | - George Y Liu
- Division of Pediatric Infectious Diseases, University of California San Diego School of Medicine, La Jolla, CA
| | - Ji-Xin Cheng
- Department of Biomedical Engineering, Boston University, Boston, MA.,Department of Chemistry, Boston University, Boston, MA.,Department of Electrical & Computer Engineering, Boston University, Boston, MA.,Photonics Center, Boston University, Boston, MA
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37
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Vezina B, Al-Harbi H, Ramay HR, Soust M, Moore RJ, Olchowy TWJ, Alawneh JI. Sequence characterisation and novel insights into bovine mastitis-associated Streptococcus uberis in dairy herds. Sci Rep 2021; 11:3046. [PMID: 33542314 PMCID: PMC7862697 DOI: 10.1038/s41598-021-82357-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Accepted: 01/20/2021] [Indexed: 12/16/2022] Open
Abstract
Streptococcus uberis is one of the most frequent mastitis-causing pathogens isolated from dairy cows. Further understanding of S. uberis genetics may help elucidate the disease pathogenesis. We compared the genomes of S. uberis isolates cultured from dairy cows located in distinctly different geographic regions of Australia. All isolates had novel multi locus sequence types (MLST) indicating a highly diverse population of S. uberis. Global clonal complexes (GCC) were more conserved. GCC ST86 and GCC ST143 represented 30% of the total isolates (n = 27) and were clustered within different geographic regions. Core genome phylogeny revealed low phylogenetic clustering by region, isolation source, and MLST. Identification of putative sortase (srtA) substrates and generation of a custom putative virulence factor database revealed genes which may explain the affinity of S. uberis for mammary tissue, evasion of antimicrobial efforts and disease pathogenesis. Of 27 isolates, four contained antibiotic resistance genes including an antimicrobial resistance cluster containing mel/mef(A), mrsE, vatD, lnuD, and transposon-mediated lnuC was also identified. These are novel genes for S. uberis, which suggests interspecies lateral gene transfer. The presence of resistance genes across the two geographic regions tested within one country supports the need for a careful, tailored, implementation and monitoring of antimicrobial stewardship.
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Affiliation(s)
- Ben Vezina
- Good Clinical Practice Research Group (GCPRG), The University of Queensland, School of Veterinary Science, Gatton, QLD, 4343, Australia.,Centre for Cell Factories and Biopolymers, Griffith Institute for Drug Discovery, Griffith University, Nathan, Australia
| | - Hulayyil Al-Harbi
- The University of Queensland, School of Veterinary Science, Gatton, QLD, 4343, Australia
| | - Hena R Ramay
- International Microbiome Centre, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Martin Soust
- Terragen Biotech Pty Ltd., Coolum Beach, QLD, 4573, Australia
| | - Robert J Moore
- School of Science, RMIT University, Bundoora, Melbourne, 3083, Australia
| | - Timothy W J Olchowy
- Good Clinical Practice Research Group (GCPRG), The University of Queensland, School of Veterinary Science, Gatton, QLD, 4343, Australia.,Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, T3R 1J3, Canada
| | - John I Alawneh
- Good Clinical Practice Research Group (GCPRG), The University of Queensland, School of Veterinary Science, Gatton, QLD, 4343, Australia. .,The University of Queensland, School of Veterinary Science, Gatton, QLD, 4343, Australia.
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38
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Mudzana R, Mavenyengwa RT, Gudza-Mugabe M. Analysis of virulence factors and antibiotic resistance genes in group B streptococcus from clinical samples. BMC Infect Dis 2021; 21:125. [PMID: 33509097 PMCID: PMC7844887 DOI: 10.1186/s12879-021-05820-6] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2020] [Accepted: 01/19/2021] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Streptococcus agalacticae (Group B Streptococcus, GBS) is one of the most important causative agents of serious infections among neonates. This study was carried out to identify antibiotic resistance and virulence genes associated with GBS isolated from pregnant women. METHODS A total of 43 GBS isolates were obtained from 420 vaginal samples collected from HIV positive and negative women who were 13-35 weeks pregnant attending Antenatal Care at Chitungwiza and Harare Central Hospitals in Zimbabwe. Identification tests of GBS isolates was done using standard bacteriological methods and molecular identification testing. Antibiotic susceptibility testing was done using the modified Kirby-Bauer method and E-test strips. The boiling method was used to extract DNA and Polymerase Chain Reaction (PCR) was used to screen for 13 genes. Data was fed into SPSS 24.0. RESULTS Nine distinct virulence gene profiles were identified and hly-scpB-bca-rib 37.2% (16/43) was common. The virulence genes identified were namely hly 97.8% (42/43), scpB 90.1% (39/43), bca 86.0% (37/43), rib 69.8% (30/43) and bac 11.6% (5/43). High resistance to tetracycline 97.7% (42/43) was reported followed by 72.1% (31/43) cefazolin, 69.8% (30/43) penicillin G, 58.1% (25/43) ampicillin, 55.8% (24/43) clindamycin, 46.5% (20/43) ceftriaxone, 34.9% (15/43) chloramphenicol, and 30.2% (13/43) for both erythromycin and vancomycin using disk diffusion. Antibiotic resistance genes among the resistant and intermediate-resistant isolates showed high frequencies for tetM 97.6% (41/42) and low frequencies for ermB 34.5% (10/29), ermTR 10.3% (3/29), mefA 3.4% (1/29), tetO 2.4% (1/42) and linB 0% (0/35). The atr housekeeping gene yielded 100% (43/43) positive results, whilst the mobile genetic element IS1548 yielded 9.3% (4/43). CONCLUSION The study showed high prevalence of hly, scpB, bca and rib virulence genes in S. agalactiae strains isolated from pregnant women. Tetracycline resistance was predominantly caused by the tetM gene, whilst macrolide resistance was predominantly due to the presence of erm methylase, with the ermB gene being more prevalent. Multi-drug resistance coupled with the recovery of resistant isolates to antimicrobial agents such as penicillins indicates the importance of GBS surveillance and susceptibility tests. It was also observed that in vitro phenotypic resistance is not always accurately predicted by resistance genotypes.
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Affiliation(s)
- Raymond Mudzana
- Department of Medical Microbiology, National Polio Laboratory, University of Zimbabwe College of Health Sciences, P. O. Box A178, Avondale, Harare, Zimbabwe
| | - Rooyen T. Mavenyengwa
- Department of Medical Microbiology, National Polio Laboratory, University of Zimbabwe College of Health Sciences, P. O. Box A178, Avondale, Harare, Zimbabwe
| | - Muchaneta Gudza-Mugabe
- Faculty of Health Sciences, Institute of Infectious Diseases and Molecular Medicine, University of Cape Town, Room No. 3.22 Falmouth Building, Anzio Road, Observatory, Cape Town, 7925 South Africa
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Alves-Barroco C, Paquete-Ferreira J, Santos-Silva T, Fernandes AR. Singularities of Pyogenic Streptococcal Biofilms - From Formation to Health Implication. Front Microbiol 2021; 11:584947. [PMID: 33424785 PMCID: PMC7785724 DOI: 10.3389/fmicb.2020.584947] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2020] [Accepted: 11/20/2020] [Indexed: 01/09/2023] Open
Abstract
Biofilms are generally defined as communities of cells involved in a self-produced extracellular matrix adhered to a surface. In biofilms, the bacteria are less sensitive to host defense mechanisms and antimicrobial agents, due to multiple strategies, that involve modulation of gene expression, controlled metabolic rate, intercellular communication, composition, and 3D architecture of the extracellular matrix. These factors play a key role in streptococci pathogenesis, contributing to therapy failure and promoting persistent infections. The species of the pyogenic group together with Streptococcus pneumoniae are the major pathogens belonging the genus Streptococcus, and its biofilm growth has been investigated, but insights in the genetic origin of biofilm formation are limited. This review summarizes pyogenic streptococci biofilms with details on constitution, formation, and virulence factors associated with formation.
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Affiliation(s)
- Cinthia Alves-Barroco
- UCIBIO, Departamento Ciências da Vida, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, Campus de Caparica, Caparica, Portugal
| | - João Paquete-Ferreira
- UCIBIO, Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, Campus de Caparica, Caparica, Portugal
| | - Teresa Santos-Silva
- UCIBIO, Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, Campus de Caparica, Caparica, Portugal
| | - Alexandra R Fernandes
- UCIBIO, Departamento Ciências da Vida, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, Campus de Caparica, Caparica, Portugal
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40
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Benmimoun B, Papastefanaki F, Périchon B, Segklia K, Roby N, Miriagou V, Schmitt C, Dramsi S, Matsas R, Spéder P. An original infection model identifies host lipoprotein import as a route for blood-brain barrier crossing. Nat Commun 2020; 11:6106. [PMID: 33257684 PMCID: PMC7704634 DOI: 10.1038/s41467-020-19826-2] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2020] [Accepted: 11/02/2020] [Indexed: 02/06/2023] Open
Abstract
Pathogens able to cross the blood-brain barrier (BBB) induce long-term neurological sequelae and death. Understanding how neurotropic pathogens bypass this strong physiological barrier is a prerequisite to devise therapeutic strategies. Here we propose an innovative model of infection in the developing Drosophila brain, combining whole brain explants with in vivo systemic infection. We find that several mammalian pathogens are able to cross the Drosophila BBB, including Group B Streptococcus (GBS). Amongst GBS surface components, lipoproteins, and in particular the B leucine-rich Blr, are important for BBB crossing and virulence in Drosophila. Further, we identify (V)LDL receptor LpR2, expressed in the BBB, as a host receptor for Blr, allowing GBS translocation through endocytosis. Finally, we show that Blr is required for BBB crossing and pathogenicity in a murine model of infection. Our results demonstrate the potential of Drosophila for studying BBB crossing by pathogens and identify a new mechanism by which pathogens exploit the machinery of host barriers to generate brain infection.
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Affiliation(s)
- Billel Benmimoun
- Institut Pasteur, Brain Plasticity in Response to the Environment, CNRS, UMR3738, Paris, France
| | - Florentia Papastefanaki
- Laboratory of Cellular and Molecular Neurobiology-Stem Cells, Department of Neurobiology, Hellenic Pasteur Institute, Athens, Greece
| | - Bruno Périchon
- Unité de Biologie des Bactéries Pathogènes à Gram-positif, Institut Pasteur, CNRS, UMR 2001, Paris, France
| | - Katerina Segklia
- Laboratory of Cellular and Molecular Neurobiology-Stem Cells, Department of Neurobiology, Hellenic Pasteur Institute, Athens, Greece
| | - Nicolas Roby
- Institut Pasteur, Brain Plasticity in Response to the Environment, CNRS, UMR3738, Paris, France
| | - Vivi Miriagou
- Laboratory of Bacteriology, Department of Microbiology, Hellenic Pasteur Institute, Athens, Greece
| | - Christine Schmitt
- Ultrastructure UTechS Ultrastructural Bioimaging Platform, Institut Pasteur, Paris, France
| | - Shaynoor Dramsi
- Unité de Biologie des Bactéries Pathogènes à Gram-positif, Institut Pasteur, CNRS, UMR 2001, Paris, France
| | - Rebecca Matsas
- Laboratory of Cellular and Molecular Neurobiology-Stem Cells, Department of Neurobiology, Hellenic Pasteur Institute, Athens, Greece
| | - Pauline Spéder
- Institut Pasteur, Brain Plasticity in Response to the Environment, CNRS, UMR3738, Paris, France.
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41
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Rudenko O, Engelstädter J, Barnes AC. Evolutionary epidemiology of Streptococcus iniae: Linking mutation rate dynamics with adaptation to novel immunological landscapes. INFECTION, GENETICS AND EVOLUTION : JOURNAL OF MOLECULAR EPIDEMIOLOGY AND EVOLUTIONARY GENETICS IN INFECTIOUS DISEASES 2020; 85:104435. [PMID: 32569744 DOI: 10.1016/j.meegid.2020.104435] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Revised: 06/10/2020] [Accepted: 06/16/2020] [Indexed: 12/11/2022]
Abstract
Pathogens continuously adapt to changing host environments where variation in their virulence and antigenicity is critical to their long-term evolutionary success. The emergence of novel variants is accelerated in microbial mutator strains (mutators) deficient in DNA repair genes, most often from mismatch repair and oxidized-guanine repair systems (MMR and OG respectively). Bacterial MMR/OG mutants are abundant in clinical samples and show increased adaptive potential in experimental infection models, yet the role of mutators in the epidemiology and evolution of infectious disease is not well understood. Here we investigated the role of mutation rate dynamics in the evolution of a broad host range pathogen, Streptococcus iniae, using a set of 80 strains isolated globally over 40 years. We have resolved phylogenetic relationships using non-recombinant core genome variants, measured in vivo mutation rates by fluctuation analysis, identified variation in major MMR/OG genes and their regulatory regions, and phenotyped the major traits determining virulence in streptococci. We found that both mutation rate and MMR/OG genotype are remarkably conserved within phylogenetic clades but significantly differ between major phylogenetic lineages. Further, variation in MMR/OG loci correlates with occurrence of atypical virulence-associated phenotypes, infection in atypical hosts (mammals), and atypical (osseous) tissue of a vaccinated primary host. These findings suggest that mutators are likely to facilitate adaptations preceding major diversification events and may promote emergence of variation permitting colonization of a novel host tissue, novel host taxa (host jumps), and immune-escape in the vaccinated host.
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Affiliation(s)
- Oleksandra Rudenko
- The University of Queensland, School of Biological Sciences, St Lucia Campus, Brisbane, Queensland 4072, Australia
| | - Jan Engelstädter
- The University of Queensland, School of Biological Sciences, St Lucia Campus, Brisbane, Queensland 4072, Australia
| | - Andrew C Barnes
- The University of Queensland, School of Biological Sciences, St Lucia Campus, Brisbane, Queensland 4072, Australia.
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42
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Alves-Barroco C, Rivas-García L, Fernandes AR, Baptista PV. Tackling Multidrug Resistance in Streptococci - From Novel Biotherapeutic Strategies to Nanomedicines. Front Microbiol 2020; 11:579916. [PMID: 33123110 PMCID: PMC7573253 DOI: 10.3389/fmicb.2020.579916] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Accepted: 09/16/2020] [Indexed: 02/06/2023] Open
Abstract
The pyogenic streptococci group includes pathogenic species for humans and other animals and has been associated with enduring morbidity and high mortality. The main reason for the treatment failure of streptococcal infections is the increased resistance to antibiotics. In recent years, infectious diseases caused by pyogenic streptococci resistant to multiple antibiotics have been raising with a significant impact to public health and veterinary industry. The rise of antibiotic-resistant streptococci has been associated to diverse mechanisms, such as efflux pumps and modifications of the antimicrobial target. Among streptococci, antibiotic resistance emerges from previously sensitive populations as result of horizontal gene transfer or chromosomal point mutations due to excessive use of antimicrobials. Streptococci strains are also recognized as biofilm producers. The increased resistance of biofilms to antibiotics among streptococci promote persistent infection, which comprise circa 80% of microbial infections in humans. Therefore, to overcome drug resistance, new strategies, including new antibacterial and antibiofilm agents, have been studied. Interestingly, the use of systems based on nanoparticles have been applied to tackle infection and reduce the emergence of drug resistance. Herein, we present a synopsis of mechanisms associated to drug resistance in (pyogenic) streptococci and discuss some innovative strategies as alternative to conventional antibiotics, such as bacteriocins, bacteriophage, and phage lysins, and metal nanoparticles. We shall provide focused discussion on the advantages and limitations of agents considering application, efficacy and safety in the context of impact to the host and evolution of bacterial resistance.
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Affiliation(s)
- Cinthia Alves-Barroco
- UCIBIO, Departamento de Ciências da Vida, Faculdade de Ciências e Tecnologia, Universidade NOVA de Lisboa, Caparica, Portugal
| | - Lorenzo Rivas-García
- UCIBIO, Departamento de Ciências da Vida, Faculdade de Ciências e Tecnologia, Universidade NOVA de Lisboa, Caparica, Portugal.,Biomedical Research Centre, University of Granada, Granada, Spain
| | - Alexandra R Fernandes
- UCIBIO, Departamento de Ciências da Vida, Faculdade de Ciências e Tecnologia, Universidade NOVA de Lisboa, Caparica, Portugal
| | - Pedro Viana Baptista
- UCIBIO, Departamento de Ciências da Vida, Faculdade de Ciências e Tecnologia, Universidade NOVA de Lisboa, Caparica, Portugal
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Shadbad MA, Kafil HS, Rezaee MA, Farzami MR, Dehkharghani AD, Sadeghi J, Gholizadeh P, Khodaei F, Aghazadeh M. Streptococcus agalactiae clinical isolates in Northwest Iran: antibiotic susceptibility, molecular typing, and biofilm formation. GMS HYGIENE AND INFECTION CONTROL 2020; 15:Doc23. [PMID: 33214988 PMCID: PMC7656979 DOI: 10.3205/dgkh000358] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Background: Group B Streptococcus (S. agalactiae) is one of the colonizing bacteria in pregnant women which can be a causative agent of meningitis and neonatal sepsis. This organism has also been increasingly related to invasive infections in non-pregnant adults. Objective: In present study, we aimed to characterize the clonality of biofilm-producing S. agalactiae isolates from various sources from two different clinical laboratories in Tehran, Iran. Materials and Methods: S. agalactiae isolates were collected from community-acquired (CA) and hospital-acquired (HA) infections in pregnant and non-pregnant adults. The antimicrobial susceptibility patterns and biofilm formation ability were determined. In addition, pulse field gel electrophoresis (PFGE) was used to verify the clonal diversity of isolates. Results: Out of the 87 isolates, 15 (16.6%) formed biofilm. The antibiotic resistance rate was 98.85% for clindamycin, 98.85% for tetracycline, followed by 29.88% for erythromycin, 9.19% for moxifloxacin and 6.89% for levofloxacin. The PFGE patterns revealed a total of 16 different clusters consisting of 6 single types (STs). Conclusion: This study evaluated the biofilm formation of clinical S. agalactiae, which may be a step towards understanding its role in pathological processes. Biofilm formation was significant only in the hypervirulent ST-17 clone. Intraclonal spread of isolates indicates that a local lineage of isolates is responsible for infection by these bacteria.
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Affiliation(s)
- Mohammad Alipour Shadbad
- Immunology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
- Student Research Committee, Tabriz University of Medical Sciences, Tabriz, Iran
| | | | - Mohammad Ahangarzadeh Rezaee
- Immunology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
- Drug Applied Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | | | | | - Javid Sadeghi
- Biotechnology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Pourya Gholizadeh
- Immunology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Farzaneh Khodaei
- Drug Applied Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Mohammad Aghazadeh
- Immunology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
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The Novel Streptococcal Transcriptional Regulator XtgS Negatively Regulates Bacterial Virulence and Directly Represses PseP Transcription. Infect Immun 2020; 88:IAI.00035-20. [PMID: 32690636 DOI: 10.1128/iai.00035-20] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Accepted: 07/04/2020] [Indexed: 01/14/2023] Open
Abstract
Streptococcus agalactiae (group B streptococcus [GBS]) has received continuous attention for its involvement in invasive infections and its broad host range. Transcriptional regulators have an important impact on bacterial adaptation to various environments. Research on transcriptional regulators will shed new light on GBS pathogenesis. In this study, we identified a novel XRE-family transcriptional regulator encoded on the GBS genome, designated XtgS. Our data demonstrate that XtgS inactivation significantly increases bacterial survival in host blood and animal challenge test, suggesting that it is a negative regulator of GBS pathogenicity. Further transcriptomic analysis and quantitative reverse transcription-PCR (qRT-PCR) mainly indicated that XtgS significantly repressed transcription of its upstream gene pseP Based on electrophoretic mobility shift and lacZ fusion assays, we found that an XtgS homodimer directly binds a palindromic sequence in the pseP promoter region. Meanwhile, the PseP and XtgS combination naturally coexists in diverse Streptococcus genomes and has a strong association with sequence type, serotype diversification and host adaptation of GBS. Therefore, this study reveals that XtgS functions as a transcriptional regulator that negatively affects GBS virulence and directly represses PseP expression, and it provides new insights into the relationships between transcriptional regulator and genome evolution.
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45
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Complete Genome Sequence of Streptococcus agalactiae Strain 01173, Isolated from Kuwaiti Wild Fish. Microbiol Resour Announc 2020; 9:9/36/e00674-20. [PMID: 32883783 PMCID: PMC7471378 DOI: 10.1128/mra.00674-20] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Here, we report the complete genome of piscine Streptococcus agalactiae 01173 serotype Ia, which was generated using long-read sequencing technology. The bacteria were isolated from wild fish displaying signs of streptococcosis, from a fish kill incident in Kuwait. Here, we report the complete genome of piscine Streptococcus agalactiae 01173 serotype Ia, which was generated using long-read sequencing technology. The bacteria were isolated from wild fish displaying signs of streptococcosis, from a fish kill incident in Kuwait.
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46
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Zhang Z, Li Y, Hu M, Yu A. Genome reanalysis to decipher resistome, virulome, and attenuated characters of attenuated Streptococcus agalactiae strain HZAUSC001. Microb Pathog 2020; 147:104416. [PMID: 32745666 DOI: 10.1016/j.micpath.2020.104416] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Revised: 07/11/2020] [Accepted: 07/20/2020] [Indexed: 10/23/2022]
Abstract
Streptococcus agalactiae is a serious pathogen causing severe anthropozoonosis in a broad range of hosts, from aquatic animals to mammals, including humans. S. agalactiae HZAUSC001 was isolated from a moribund tilapia fish exhibiting classic clinical symptoms of streptococcosis in Zhanjiang, Guangdong, China. And it was identified as the etiological factor resulting in fish disease, but was notable because it exhibited attenuated virulence. Here, the genome of S. agalactiae HZAUSC001 was re-analyzed; we assessed the resistome and virulome and deciphered the attenuated characters of HZAUSC001. The S. agalactiae HZAUSC001 genome was assembled into one chromosome with a GC-content of 35.37% and 1972 predicted open reading frames (ORFs). Phylogenetic analysis indicated that it is evolutionarily similar to piscine GBS strains GD201008-001 and ZQ0910. After re-analyzing the published genomic sequence of HZAUSC001, we identified 38 virulence factor genes and one antibiotic-resistance gene. Note that three previously noted virulence genes, bca (C protein alpha-antigen), cpbA (choline-binding protein A) and esp (enterococcal surface protein), were absent in the virulence-attenuated strain S. agalactiae HZAUSC001 but present in the highly virulent strain S. agalactiae GD201008-001. We speculate that the absence of these three virulence genes may be associated with the attenuated traits of the HZAUSC001 strain. Collectively, our study supports that HZAUSC001 may be an excellent candidate for development of an attenuated vaccine, and our results contribute to further understanding of GBS epidemiology and surveillance targets.
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Affiliation(s)
- Ze Zhang
- College of Life Sciences, Beijing Normal University, Beijing, 100875, China; National Institute of Biological Sciences, Zhongguancun Life Science Park, Changping, 102206, Beijing, China; Tsinghua Institute of Multidisciplinary Biomedical Research, Tsinghua University, 102206, Beijing, China.
| | - Yuhui Li
- Key Laboratory of Special Pathogens and Biosafety, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, 430071, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Minqiang Hu
- School of Chemical Biology and Biotechnology, Shenzhen Graduate School, Peking University, Shenzhen, 518055, China
| | - Angen Yu
- Department of Aquatic Animal Medicine, Research Center for Marine Biology, College of Fisheries, Huazhong Agricultural University, Wuhan, Hubei, 430070, China
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Pan-GWAS of Streptococcus agalactiae Highlights Lineage-Specific Genes Associated with Virulence and Niche Adaptation. mBio 2020; 11:mBio.00728-20. [PMID: 32518186 PMCID: PMC7373188 DOI: 10.1128/mbio.00728-20] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
GBS is a leading cause of mortality in newborn babies in high- and low-income countries worldwide. Different strains of GBS are characterized by different degrees of virulence, where some are harmlessly carried by humans or animals and others are much more likely to cause disease.
The genome sequences of almost 2,000 GBS samples isolated from both animals and humans in high- and low- income countries were analyzed using a pan-genome-wide association study approach. This allowed us to identify 279 genes which are associated with different lineages of GBS, characterized by a different virulence and preferred host. Additionally, we propose that the GBS now carried in humans may have first evolved in animals before expanding clonally once adapted to the human host.
These findings are essential to help understand what is causing GBS disease and how the bacteria have evolved and are transmitted. Streptococcus agalactiae (group B streptococcus; GBS) is a colonizer of the gastrointestinal and urogenital tracts, and an opportunistic pathogen of infants and adults. The worldwide population of GBS is characterized by clonal complexes (CCs) with different invasive potentials. CC17, for example, is a hypervirulent lineage commonly associated with neonatal sepsis and meningitis, while CC1 is less invasive in neonates and more commonly causes invasive disease in adults with comorbidities. The genetic basis of GBS virulence and the extent to which different CCs have adapted to different host environments remain uncertain. We have therefore applied a pan-genome-wide association study (GWAS) approach to 1,988 GBS strains isolated from different hosts and countries. Our analysis identified 279 CC-specific genes associated with virulence, disease, metabolism, and regulation of cellular mechanisms that may explain the differential virulence potential of particular CCs. In CC17 and CC23, for example, we have identified genes encoding pilus, quorum-sensing proteins, and proteins for the uptake of ions and micronutrients which are absent in less invasive lineages. Moreover, in CC17, carriage and disease strains were distinguished by the allelic variants of 21 of these CC-specific genes. Together our data highlight the lineage-specific basis of GBS niche adaptation and virulence. The genome sequences of almost 2,000 GBS samples isolated from both animals and humans in high- and low- income countries were analyzed using a pan-genome-wide association study approach. This allowed us to identify 279 genes which are associated with different lineages of GBS, characterized by a different virulence and preferred host. Additionally, we propose that the GBS now carried in humans may have first evolved in animals before expanding clonally once adapted to the human host. These findings are essential to help understand what is causing GBS disease and how the bacteria have evolved and are transmitted.
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Lannes-Costa PS, Baraúna RA, Ramos JN, Veras JFC, Conceição MVR, Vieira VV, de Mattos-Guaraldi AL, Ramos RTJ, Doran KS, Silva A, Nagao PE. Comparative genomic analysis and identification of pathogenicity islands of hypervirulent ST-17 Streptococcus agalactiae Brazilian strain. INFECTION GENETICS AND EVOLUTION 2020; 80:104195. [DOI: 10.1016/j.meegid.2020.104195] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2019] [Revised: 01/09/2020] [Accepted: 01/14/2020] [Indexed: 11/29/2022]
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49
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Mekvimol T, Poonthong G, Chaipunna C, Pumipuntu N. Antimicrobial activity of marigold (Tagetes erecta), mulberry (Morus indica), and red shallot (Allium ascalonicum) extracts against Streptococcus agalactiae. INTERNATIONAL JOURNAL OF ONE HEALTH 2020. [DOI: 10.14202/ijoh.2020.56-60] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Background and Aim: The increasing antimicrobial resistance with reduced susceptibility to antimicrobial drugs is becoming a major concern for both human and animal, which raises health morbidity and mortality rate of cases that cannot be treated by antibiotics. Nowadays, there are many efforts to minimize the misuse of antibiotics. This study evaluated the antimicrobial activity of the crude ethanolic extracts of three Thai herbs divided in four groups; petals of marigold (Tagetes erecta), mulberry leaves and root barks (Morus indica), and whole onions of red shallot (Allium ascalonicum) against Streptococcus agalactiae.
Materials and Methods: The antimicrobial activity of four groups of the crude extracts using absolute ethanol from three Thai herbs was tested against standard strains of S. agalactiae using the agar well diffusion method. The commercial antibiotics ceftriaxone and erythromycin were used as positive control standards to determine the sensitivity of S. agalactiae.
Results: The result showed that all four groups of Thai herbal extract had inhibitory activity against standard strains of S. agalactiae. The inhibitory concentration test values were obtained using the dilution test at 25, 50, and 75 mg/ml. The maximum antimicrobial activity against S. agalactiae was observed in the ethanolic extracts from red shallot extract, followed by leaves of mulberry, petals of marigold, and root barks of mulberry, respectively.
Conclusion: The results demonstrated that the crude extract of three Thai herbs had antimicrobial activity inhibiting the growth of S. agalactiae and suggesting that they may be useful in the treatment of S. agalactiae infections in humans and animals.
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Affiliation(s)
- Tanawadee Mekvimol
- One Health Research Unit, Faculty of Veterinary Sciences, Mahasarakham University, Maha Sarakham 44000, Thailand
| | - Gannika Poonthong
- One Health Research Unit, Faculty of Veterinary Sciences, Mahasarakham University, Maha Sarakham 44000, Thailand
| | - Chayanit Chaipunna
- One Health Research Unit, Faculty of Veterinary Sciences, Mahasarakham University, Maha Sarakham 44000, Thailand
| | - Natapol Pumipuntu
- One Health Research Unit, Faculty of Veterinary Sciences, Mahasarakham University, Maha Sarakham 44000, Thailand; Office of Academic Affairs, Faculty of Veterinary Sciences, Mahasarakham University, Maha Sarakham 44000, Thailand
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50
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Carreras-Abad C, Ramkhelawon L, Heath PT, Le Doare K. A Vaccine Against Group B Streptococcus: Recent Advances. Infect Drug Resist 2020; 13:1263-1272. [PMID: 32425562 PMCID: PMC7196769 DOI: 10.2147/idr.s203454] [Citation(s) in RCA: 52] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2019] [Accepted: 03/10/2020] [Indexed: 01/12/2023] Open
Abstract
Group B streptococcus (GBS) causes a high burden of neonatal and infant disease globally. Implementing a vaccine for pregnant women is a promising strategy to prevent neonatal and infant GBS disease and has been identified as a priority by the World Health Organisation (WHO). GBS serotype-specific polysaccharide – protein conjugate vaccines are at advanced stages of development, but a large number of participants would be required to undertake Phase III clinical efficacy trials. Efforts are therefore currently focused on establishing serocorrelates of protection in natural immunity studies as an alternative pathway for licensure of a GBS vaccine, followed by Phase IV studies to evaluate safety and effectiveness. Protein vaccines are in earlier stages of development but are highly promising as they might confer protection irrespective of serotype. Further epidemiological, immunological and health economic studies are required to enable the vaccine to reach its target population as soon as possible.
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Affiliation(s)
- Clara Carreras-Abad
- Paediatric Infectious Diseases Research Group and Vaccine Institute, Institute for Infection and Immunity, St George's, University of London, London, UK.,Department of Paediatrics, Obstetrics and Gynecology and Preventive Medicine and Public Health, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Laxmee Ramkhelawon
- Paediatric Infectious Diseases Research Group and Vaccine Institute, Institute for Infection and Immunity, St George's, University of London, London, UK
| | - Paul T Heath
- Paediatric Infectious Diseases Research Group and Vaccine Institute, Institute for Infection and Immunity, St George's, University of London, London, UK
| | - Kirsty Le Doare
- Paediatric Infectious Diseases Research Group and Vaccine Institute, Institute for Infection and Immunity, St George's, University of London, London, UK.,Pathogen Immunity Group, Public Health England, Porton Down,UK.,Medical Research Council/Uganda Virus Research Institute and London School of Hygiene and Tropical Medicine, Uganda Research Unit, Entebbe, Uganda
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