Pub Date : 2019-12-23DOI: 10.5772/intechopen.89102
Manju O. Pai, V. Pai, Pratima Gupta, A. Chakraborti
Streptococcus agalactiae or Group B streptococcus (GBS) is an opportunistic human pathogen known for their invasive diseases caused in newborns, pregnant women, and nonpregnant adults. This pathogen even being an asymptomatic colonizer of adult humans, still they result in a broad range of disease manifesta-tions starting from mild skin diseases to pneumonia, meningitis, and septicemia. Of the 10 GBS capsular types, the majority of invasive neonatal diseases are associated with the serotype III. GBS is a pathogen that has developed some strategies to resist host immune defenses. The formidable array of GBS virulence factors makes this bacterium at the forefront of neonatal pathogens. The involvement of bacterial components in the host-pathogen interaction of GBS pathogenesis and its related diseases is thought to be due to a variety of virulence factors expressed by Streptococcus agalactiae . Pathogenic factors of streptococcus promote infections by their coordinated activity. These factors/determinants initially get a stimulus by the communication between specific ligands and their respective receptors in a host-pathogen interaction. These in turn activate adhesion and invasion mechanisms by mediating the attachment of pathogen via cell wall associated/secretory proteins, e.g., adhesins followed by their entry into the host cell eventually deciding their fate to live by activation of mechanisms like phagocytosis. These mediators/deter-minants also modulate the immune responses by the host toward the pathogen. A number of new GBS surface-exposed or secreted proteins have been identified (GBS immunogenic bacterial adhesion protein, leucine-rich repeat of GBS, serine-rich repeat proteins), the three-dimensional structures of known streptococcal proteins ( α C protein, C5a peptidase) have been solved, and an understanding of the pathogenetic role of “old” and new determinants
{"title":"Cell Surface and Cytosolic Proteins of Group B Streptococcus Adding New Dimensions in Its Colonization and Pathogenesis","authors":"Manju O. Pai, V. Pai, Pratima Gupta, A. Chakraborti","doi":"10.5772/intechopen.89102","DOIUrl":"https://doi.org/10.5772/intechopen.89102","url":null,"abstract":"Streptococcus agalactiae or Group B streptococcus (GBS) is an opportunistic human pathogen known for their invasive diseases caused in newborns, pregnant women, and nonpregnant adults. This pathogen even being an asymptomatic colonizer of adult humans, still they result in a broad range of disease manifesta-tions starting from mild skin diseases to pneumonia, meningitis, and septicemia. Of the 10 GBS capsular types, the majority of invasive neonatal diseases are associated with the serotype III. GBS is a pathogen that has developed some strategies to resist host immune defenses. The formidable array of GBS virulence factors makes this bacterium at the forefront of neonatal pathogens. The involvement of bacterial components in the host-pathogen interaction of GBS pathogenesis and its related diseases is thought to be due to a variety of virulence factors expressed by Streptococcus agalactiae . Pathogenic factors of streptococcus promote infections by their coordinated activity. These factors/determinants initially get a stimulus by the communication between specific ligands and their respective receptors in a host-pathogen interaction. These in turn activate adhesion and invasion mechanisms by mediating the attachment of pathogen via cell wall associated/secretory proteins, e.g., adhesins followed by their entry into the host cell eventually deciding their fate to live by activation of mechanisms like phagocytosis. These mediators/deter-minants also modulate the immune responses by the host toward the pathogen. A number of new GBS surface-exposed or secreted proteins have been identified (GBS immunogenic bacterial adhesion protein, leucine-rich repeat of GBS, serine-rich repeat proteins), the three-dimensional structures of known streptococcal proteins ( α C protein, C5a peptidase) have been solved, and an understanding of the pathogenetic role of “old” and new determinants","PeriodicalId":325009,"journal":{"name":"Staphylococcus and Streptococcus","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-12-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131154459","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-08-19DOI: 10.5772/INTECHOPEN.88455
Li-wen Chang, M. Hsu, Ying-yuan Zhang
Nemonoxacin (Taigexyn ® ), a novel C-8-methoxy non-fluorinated quinolone, has been approved for use in community-acquired pneumonia (CAP) in Taiwan (2014) and mainland China (2016). The FDA granted nemonoxacin ‘qualified infectious disease product’ and ‘fast-track’ designations for CAP and acute bacterial skin and skin structure infection in December 2013. It possesses a broad spectrum of bactericidal activity against typical and atypical respiratory pathogens. In particular, nemonoxacin has activity against resistant Gram-positive cocci, including penicillin-resistant Streptococcus pneumoniae and methicillin-resistant Staphylococcus aureus . Oral nemonoxacin was compared with oral levofloxacin for efficacy and safety in three randomized, double-blinded, controlled Phase II–III clinical trials for the treatment of CAP. This article will review the microbiological profile of nemonoxacin against respiratory pathogens including S. pneumoniae and S. aureus , and microbiological outcome data from the three Phase II–III studies.
{"title":"Nemonoxacin (Taigexyn®): A New Non-Fluorinated Quinolone","authors":"Li-wen Chang, M. Hsu, Ying-yuan Zhang","doi":"10.5772/INTECHOPEN.88455","DOIUrl":"https://doi.org/10.5772/INTECHOPEN.88455","url":null,"abstract":"Nemonoxacin (Taigexyn ® ), a novel C-8-methoxy non-fluorinated quinolone, has been approved for use in community-acquired pneumonia (CAP) in Taiwan (2014) and mainland China (2016). The FDA granted nemonoxacin ‘qualified infectious disease product’ and ‘fast-track’ designations for CAP and acute bacterial skin and skin structure infection in December 2013. It possesses a broad spectrum of bactericidal activity against typical and atypical respiratory pathogens. In particular, nemonoxacin has activity against resistant Gram-positive cocci, including penicillin-resistant Streptococcus pneumoniae and methicillin-resistant Staphylococcus aureus . Oral nemonoxacin was compared with oral levofloxacin for efficacy and safety in three randomized, double-blinded, controlled Phase II–III clinical trials for the treatment of CAP. This article will review the microbiological profile of nemonoxacin against respiratory pathogens including S. pneumoniae and S. aureus , and microbiological outcome data from the three Phase II–III studies.","PeriodicalId":325009,"journal":{"name":"Staphylococcus and Streptococcus","volume":"102 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129483394","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-08-14DOI: 10.5772/intechopen.88182
Adam J. Quek, J. Whisstock, R. Law
Group A Streptococcus pyogenes (GAS) is a human pathogen that commonly causes superficial infections such as pharyngitis, but can also lead to systemic and fatal diseases. GAS infection remains to be a major threat in regions with insufficient medical infrastructures, leading to half a million deaths annually worldwide. The pathogenesis of GAS is mediated by a number of virulence factors, which function to facilitate bacterial colonization, immune evasion, and deep tissue invasion. In this review, we will discuss the mechanism of molecular interaction between the host protein and virulence factors that target the fibrinolytic system, including streptokinase (SK), plasminogen-binding group A streptococcal M-like protein (PAM), and streptococcal inhibitor of complement (SIC). We will discuss our current understanding, through structural studies, on how these proteins manipulate the fibrinolytic system during infection.
{"title":"Toward Better Understanding on How Group AStreptococcusManipulates Human Fibrinolytic System","authors":"Adam J. Quek, J. Whisstock, R. Law","doi":"10.5772/intechopen.88182","DOIUrl":"https://doi.org/10.5772/intechopen.88182","url":null,"abstract":"Group A Streptococcus pyogenes (GAS) is a human pathogen that commonly causes superficial infections such as pharyngitis, but can also lead to systemic and fatal diseases. GAS infection remains to be a major threat in regions with insufficient medical infrastructures, leading to half a million deaths annually worldwide. The pathogenesis of GAS is mediated by a number of virulence factors, which function to facilitate bacterial colonization, immune evasion, and deep tissue invasion. In this review, we will discuss the mechanism of molecular interaction between the host protein and virulence factors that target the fibrinolytic system, including streptokinase (SK), plasminogen-binding group A streptococcal M-like protein (PAM), and streptococcal inhibitor of complement (SIC). We will discuss our current understanding, through structural studies, on how these proteins manipulate the fibrinolytic system during infection.","PeriodicalId":325009,"journal":{"name":"Staphylococcus and Streptococcus","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-08-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130590298","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-07-31DOI: 10.5772/INTECHOPEN.88524
Khalid I. Al-Qumaizi, R. Anwer
Streptococcus pneumoniae ( S. pneumoniae ) has a multifaceted bond with its human host and causing several diseases in children and adults when host flexible immunity and bacterial acquisition factors allow them to invade essentially sterile spots, such as the middle ear spaces (causes otitis media), lungs (causes pneumo-nia), bloodstream (causes sepsis) and meninges (causes meningitis). In the early 1940s, management of pneumococcal infections used to be somewhat straightfor-ward, and penicillin commonly was the antibiotic of choice. Soon after mainstreaming antibiotic usage, worldwide emergence of antibiotic resistance among S. pneumoniae isolates has changed this approach. Multiple factors, like prior antibiotic use, inappropriate usage of antibiotics especially in young age, and day care attendance are the most commonly identified risk features for the spread of penicillin resistance and other multiple-antibiotic resistance. Basic fundamental mechanisms of most pneumococcal resistances have been identified, several orga-nizations like WHO, CDC, BSAC, EUCAST started campaigns for appropriate antibiotic use and also the introduction of pneumococcal conjugate vaccines have been recommended to limit the further emergence and spread of pneumococcal resistant.
{"title":"An Emerging Multidrug-Resistant Pathogen: Streptococcus pneumoniae","authors":"Khalid I. Al-Qumaizi, R. Anwer","doi":"10.5772/INTECHOPEN.88524","DOIUrl":"https://doi.org/10.5772/INTECHOPEN.88524","url":null,"abstract":"Streptococcus pneumoniae ( S. pneumoniae ) has a multifaceted bond with its human host and causing several diseases in children and adults when host flexible immunity and bacterial acquisition factors allow them to invade essentially sterile spots, such as the middle ear spaces (causes otitis media), lungs (causes pneumo-nia), bloodstream (causes sepsis) and meninges (causes meningitis). In the early 1940s, management of pneumococcal infections used to be somewhat straightfor-ward, and penicillin commonly was the antibiotic of choice. Soon after mainstreaming antibiotic usage, worldwide emergence of antibiotic resistance among S. pneumoniae isolates has changed this approach. Multiple factors, like prior antibiotic use, inappropriate usage of antibiotics especially in young age, and day care attendance are the most commonly identified risk features for the spread of penicillin resistance and other multiple-antibiotic resistance. Basic fundamental mechanisms of most pneumococcal resistances have been identified, several orga-nizations like WHO, CDC, BSAC, EUCAST started campaigns for appropriate antibiotic use and also the introduction of pneumococcal conjugate vaccines have been recommended to limit the further emergence and spread of pneumococcal resistant.","PeriodicalId":325009,"journal":{"name":"Staphylococcus and Streptococcus","volume":"44 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124794882","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-04-26DOI: 10.5772/INTECHOPEN.85620
V. Velasco, M. Quezada-Aguiluz, H. Bello-Toledo
Staphylococcus aureus ( S. aureus ) can cause a wide variety of infections in humans, such as skin and soft tissue infections, bacteremia, pneumonia, and food poisoning. This pathogen could be carried on the nares, skin, and hair of animals and humans, representing a serious problem at the hospital and the community level as well as in the food industry. The pathogenicity of S. aureus is given by bacterial structures and extracellular products, among which are toxins, which could cause staphylococcal diseases transmitted by food (SFD). S. aureus has the ability to develop resistance to antimicrobials (AMR), highlighting methicillin-resistant strains (MRSA), which have resistance to all beta-lactam antibiotics, except to the fifth-generation cephalosporins. Methicillin resistance is primarily mediated by three mechanisms: production of an altered penicillin-binding protein PBP2’ (or PBP2a), encoded by the mecA gene; high production of β -lactamase in borderline oxacillin-resistant Staphylococcus aureus (BORSA); and mutations in the native PBPs, called modified S. aureus (MODSA). Emerging strains have been isolated from meat-producing animals and retail meat, such as MRSA, MRSA ST398 (associated with livestock), multidrug-resistant (MDR) S. aureus , and enterotoxin-producing S. aureus . Therefore, there is a risk of contamination of meat and meat products during the different processing stages of the meat supply chain.
{"title":"Staphylococcus aureus in the Meat Supply Chain: Detection Methods, Antimicrobial Resistance, and Virulence Factors","authors":"V. Velasco, M. Quezada-Aguiluz, H. Bello-Toledo","doi":"10.5772/INTECHOPEN.85620","DOIUrl":"https://doi.org/10.5772/INTECHOPEN.85620","url":null,"abstract":"Staphylococcus aureus ( S. aureus ) can cause a wide variety of infections in humans, such as skin and soft tissue infections, bacteremia, pneumonia, and food poisoning. This pathogen could be carried on the nares, skin, and hair of animals and humans, representing a serious problem at the hospital and the community level as well as in the food industry. The pathogenicity of S. aureus is given by bacterial structures and extracellular products, among which are toxins, which could cause staphylococcal diseases transmitted by food (SFD). S. aureus has the ability to develop resistance to antimicrobials (AMR), highlighting methicillin-resistant strains (MRSA), which have resistance to all beta-lactam antibiotics, except to the fifth-generation cephalosporins. Methicillin resistance is primarily mediated by three mechanisms: production of an altered penicillin-binding protein PBP2’ (or PBP2a), encoded by the mecA gene; high production of β -lactamase in borderline oxacillin-resistant Staphylococcus aureus (BORSA); and mutations in the native PBPs, called modified S. aureus (MODSA). Emerging strains have been isolated from meat-producing animals and retail meat, such as MRSA, MRSA ST398 (associated with livestock), multidrug-resistant (MDR) S. aureus , and enterotoxin-producing S. aureus . Therefore, there is a risk of contamination of meat and meat products during the different processing stages of the meat supply chain.","PeriodicalId":325009,"journal":{"name":"Staphylococcus and Streptococcus","volume":"29 5","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131575273","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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