Virulence factors, antibiotic resistance mechanisms and the prevalence of resistance worldwide in Streptococcus pneumoniae

2004 ◽  
Vol 15 (1) ◽  
pp. 27-39 ◽  
Author(s):  
Orsolya Dobay ◽  
Ferenc Rozgonyi ◽  
Sebastian GB Amyes
Keyword(s):  
Antibiotic Resistance ◽  
Streptococcus Pneumoniae ◽  
Virulence Factors ◽  
Resistance Mechanisms

scholarly journals Antibiotic resistance, virulence, and phylogenetic analysis of Escherichia coli strains isolated from free-living birds in human habitats

PLoS ONE ◽  
2022 ◽  
Vol 17 (1) ◽  
pp. e0262236
Author(s):  
Bartosz Rybak ◽  
Beata Krawczyk ◽  
Beata Furmanek-Blaszk ◽  
Magdalena Wysocka ◽  
Magdalena Fordon ◽  
...  
Keyword(s):  
Antibiotic Resistance ◽  
Virulence Factors ◽  
Iron Acquisition ◽  
Antibiotic Resistance Genes ◽  
Resistance Mechanisms ◽  
Wild Birds ◽  
Phylogenetic Groups ◽  
Faecal Samples ◽  
Class 1 ◽  
Genes Encoding

Wild birds can be colonized by bacteria, which are often resistant to antibiotics and have various virulence profiles. The aim of this study was to analyze antibiotic resistance mechanisms and virulence profiles in relation to the phylogenetic group of E. coli strains that were isolated from the GI tract of wildfowl. Out of 241 faecal samples, presence of E. coli resistant to a cephalosporin (ESBL/AmpC) was estimated for 33 isolates (13,7%). Based on the analysis of the coexistence of 4 genes encoding ESBLs/AmpC (blaCTX-M, blaTEM, blaSHV, blaAmpC) and class 1 and 2 integrons genes (intI1, intI2) a subset of two resistance profiles was observed among the investigated E. coli isolates carrying blaAmpC, blaSHV, and blaCTX-M, blaTEM, class 1 and 2 integrons, respectively. The E. coli isolates were categorized into 4 phylogenetic groups A (39.4%), B2 (24.25%), D (24.25%) and B1 (12.1%). The pathogenic B2 and D groups were mainly typical for the Laridae family. Among the 28 virulence factors (Vfs) detected in pathogenic phylogenetic groups B2 and D, 7 were exclusively found in those groups (sfa, vat, tosA, tosB, hly, usp, cnf), while 4 VFs (fecA, fyuA, irp2, kspMTII) showed a statistically significant association (P≤0.05) with phylogroups A and B1. Our results indicated that strains belonging to commensal phylogroups A/B1 possess extensive iron acquisition systems (93,9%) and autotransporters (60,6%), typical for pathogens, hence we suggest that these strains evolve towards higher levels of virulence. This study, which is a point assessment of the virulence and drug resistance potential of wild birds, confirms the importance of taking wild birds as a reservoir of strains that pose a growing threat to humans. The E. coli analyzed in our study derive from different phylogenetic groups and possess an arsenal of antibiotic resistance genes and virulence factors that contribute to their ability to cause diseases.

scholarly journals JMM Profile: Streptococcus pneumoniae: sugar-coated captain of the men of death

2021 ◽  
Vol 70 (11) ◽  
Author(s):  
Tina H. Dao ◽  
Jason W. Rosch
Keyword(s):  
Antibiotic Resistance ◽  
Streptococcus Pneumoniae ◽  
Virulence Factors ◽  
Immune Evasion ◽  
Type Species ◽  
Genetic Material ◽  
Human Pathogen ◽  
Content Type ◽  
Invasive Diseases ◽  
Respiratory Microbiota

Streptococcus pneumoniae is a highly adept human pathogen. A frequent asymptomatic member of the respiratory microbiota, the pneumococcus has a remarkable capacity to cause mucosal (pneumonia and otitis media) and invasive diseases (bacteremia, meningitis). In addition, the organism utilizes a vast battery of virulence factors for tissue and immune evasion. Though recognized as a significant cause of pneumonia for over a century, efforts to develop more effective vaccines remain ongoing. The pathogen’s inherent capacity to exchange genetic material is critical to the pneumococcus’ success. This feature historically facilitated essential discoveries in genetics and is vital for disseminating antibiotic resistance and vaccine evasion.

Quintuplex PCR to Detect Antibiotic Resistance Genes in Streptococcus pneumoniae

2016 ◽  
Vol 1 (2) ◽  
pp. 22 ◽  
Author(s):  
Navindra Kumari Palanisamy ◽  
Parasakthi Navaratnam ◽  
Shamala Devi Sekaran
Keyword(s):  
Antibiotic Resistance ◽  
Streptococcus Pneumoniae ◽  
Resistance Genes ◽  
Bacterial Pathogen ◽  
Antibiotic Resistance Genes ◽  
Pcr Amplification ◽  
Penicillin Resistance ◽  
Penicillin Binding Proteins ◽  
Efflux Mechanism ◽  
Mic Value

Introduction: Streptococcus pneumoniae is an important bacterial pathogen, causing respiratory infection. Penicillin resistance in S. pneumoniae is associated with alterations in the penicillin binding proteins, while resistance to macrolides is conferred either by the modification of the ribosomal target site or efflux mechanism. This study aimed to characterize S. pneumoniae and its antibiotic resistance genes using 2 sets of multiplex PCRs. Methods: A quintuplex and triplex PCR was used to characterize the pbp1A, ermB, gyrA, ply, and the mefE genes. Fifty-eight penicillin sensitive strains (PSSP), 36 penicillin intermediate strains (PISP) and 26 penicillin resistance strains (PRSP) were used. Results: Alteration in pbp1A was only observed in PISP and PRSP strains, while PCR amplification of the ermB or mefE was observed only in strains with reduced susceptibility to erythromycin. The assay was found to be sensitive as simulated blood cultures showed the lowest level of detection to be 10cfu. Conclusions: As predicted, the assay was able to differentiate penicillin susceptible from the non-susceptible strains based on the detection of the pbp1A gene, which correlated with the MIC value of the strains.

MICROORGANISMS ANTIBIOTIC RESISTANCE MECHANISMS – PRESENT VIEW

2019 ◽  
Vol 21 (10) ◽  
pp. 125-130
Author(s):  
Пушилина А.Д. ◽  
◽  
Коменкова Т.С. ◽  
Зайцева Е.А. ◽  
Keyword(s):  
Antibiotic Resistance ◽  
Resistance Mechanisms ◽  
Present View

scholarly journals Antimicrobials and Food-Related Stresses as Selective Factors for Antibiotic Resistance along the Farm to Fork Continuum

Antibiotics ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 671
Author(s):  
Federica Giacometti ◽  
Hesamaddin Shirzad-Aski ◽  
Susana Ferreira
Keyword(s):  
Antibiotic Resistance ◽  
Food Safety ◽  
Antimicrobial Resistance ◽  
Food Processing ◽  
Resistance Mechanisms ◽  
Human Environment ◽  
Real Risk ◽  
Cross Adaptation ◽  
Novel Approaches

Antimicrobial resistance (AMR) is a global problem and there has been growing concern associated with its widespread along the animal–human–environment interface. The farm-to-fork continuum was highlighted as a possible reservoir of AMR, and a hotspot for the emergence and spread of AMR. However, the extent of the role of non-antibiotic antimicrobials and other food-related stresses as selective factors is still in need of clarification. This review addresses the use of non-antibiotic stressors, such as antimicrobials, food-processing treatments, or even novel approaches to ensure food safety, as potential drivers for resistance to clinically relevant antibiotics. The co-selection and cross-adaptation events are covered, which may induce a decreased susceptibility of foodborne bacteria to antibiotics. Although the available studies address the complexity involved in these phenomena, further studies are needed to help better understand the real risk of using food-chain-related stressors, and possibly to allow the establishment of early warnings of potential resistance mechanisms.

scholarly journals Virulence Factors in Coagulase-Negative Staphylococci

Pathogens ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 170
Author(s):  
Angela França ◽  
Vânia Gaio ◽  
Nathalie Lopes ◽  
Luís D. R. Melo
Keyword(s):  
Antibiotic Resistance ◽  
Virulence Factors ◽  
Resistance Genes ◽  
Biofilm Formation ◽  
Antibiotic Resistance Genes ◽  
Coagulase Negative Staphylococci ◽  
Healthcare Associated ◽  
Major Pathogens

Coagulase-negative staphylococci (CoNS) have emerged as major pathogens in healthcare-associated facilities, being S. epidermidis, S. haemolyticus and, more recently, S. lugdunensis, the most clinically relevant species. Despite being less virulent than the well-studied pathogen S. aureus, the number of CoNS strains sequenced is constantly increasing and, with that, the number of virulence factors identified in those strains. In this regard, biofilm formation is considered the most important. Besides virulence factors, the presence of several antibiotic-resistance genes identified in CoNS is worrisome and makes treatment very challenging. In this review, we analyzed the different aspects involved in CoNS virulence and their impact on health and food.

scholarly journals Sorting out the Superbugs: Potential of Sortase A Inhibitors among Other Antimicrobial Strategies to Tackle the Problem of Antibiotic Resistance

Antibiotics ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 164 ◽  
Author(s):  
Nikita Zrelovs ◽  
Viktorija Kurbatska ◽  
Zhanna Rudevica ◽  
Ainars Leonchiks ◽  
Davids Fridmanis
Keyword(s):  
Cell Wall ◽  
Antibiotic Resistance ◽  
Pathogenic Bacteria ◽  
Resistance Mechanisms ◽  
Surface Proteins ◽  
Sortase A ◽  
Inhibitory Compounds ◽  
Alternative Means ◽  
Alternative Approaches ◽  
Conventional Antibiotics

Rapid spread of antibiotic resistance throughout the kingdom bacteria is inevitably bringing humanity towards the “post-antibiotic” era. The emergence of so-called “superbugs”—pathogen strains that develop resistance to multiple conventional antibiotics—is urging researchers around the globe to work on the development or perfecting of alternative means of tackling the pathogenic bacteria infections. Although various conceptually different approaches are being considered, each comes with its advantages and drawbacks. While drug-resistant pathogens are undoubtedly represented by both Gram(+) and Gram(−) bacteria, possible target spectrum across the proposed alternative approaches of tackling them is variable. Numerous anti-virulence strategies aimed at reducing the pathogenicity of target bacteria rather than eliminating them are being considered among such alternative approaches. Sortase A (SrtA) is a membrane-associated cysteine protease that catalyzes a cell wall sorting reaction by which surface proteins, including virulence factors, are anchored to the bacterial cell wall of Gram(+) bacteria. Although SrtA inhibition seems perspective among the Gram-positive pathogen-targeted antivirulence strategies, it still remains less popular than other alternatives. A decrease in virulence due to inactivation of SrtA activity has been extensively studied in Staphylococcus aureus, but it has also been demonstrated in other Gram(+) species. In this manuscript, results of past studies on the discovery of novel SrtA inhibitory compounds and evaluation of their potency were summarized and commented on. Here, we discussed the rationale behind the inhibition of SrtA, raised some concerns on the comparability of the results from different studies, and touched upon the possible resistance mechanisms as a response to implementation of such therapy in practice. The goal of this article is to encourage further studies of SrtA inhibitory compounds.

scholarly journals Streptococcus pneumoniae and Its Virulence Factors H2O2 and Pneumolysin Are Potent Mediators of the Acute Chest Syndrome in Sickle Cell Disease

Toxins ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 157
Author(s):  
Joyce Gonzales ◽  
Trinad Chakraborty ◽  
Maritza Romero ◽  
Mobarak Abu Mraheil ◽  
Abdullah Kutlar ◽  
...  
Keyword(s):  
Streptococcus Pneumoniae ◽  
Sickle Cell Disease ◽  
Virulence Factors ◽  
Sickle Cell ◽  
Biological Activities ◽  
Acute Chest Syndrome ◽  
Antibiotics Resistance ◽  
Cell Disease ◽  
Antibiotic Drug ◽  
Tract Infections

Sickle cell disease (SCD) is one of the most common autosomal recessive disorders in the world. Due to functional asplenia, a dysfunctional antibody response, antibiotic drug resistance and poor response to immunization, SCD patients have impaired immunity. A leading cause of hospitalization and death in SCD patients is the acute chest syndrome (ACS). This complication is especially manifested upon infection of SCD patients with Streptococcus pneumoniae (Spn)—a facultative anaerobic Gram-positive bacterium that causes lower respiratory tract infections. Spn has developed increased rates of antibiotics resistance and is particularly virulent in SCD patients. The primary defense against Spn is the generation of reactive oxygen species (ROS) during the oxidative burst of neutrophils and macrophages. Paradoxically, Spn itself produces high levels of the ROS hydrogen peroxide (H2O2) as a virulence strategy. Apart from H2O2, Spn also secretes another virulence factor, i.e., the pore-forming exotoxin pneumolysin (PLY), a potent mediator of lung injury in patients with pneumonia in general and particularly in those with SCD. PLY is released early on in infection either by autolysis or bacterial lysis following the treatment with antibiotics and has a broad range of biological activities. This review will discuss recent findings on the role of pneumococci in ACS pathogenesis and on strategies to counteract the devastating effects of its virulence factors on the lungs in SCD patients.

scholarly journals Nitric oxide (NO) elicits aminoglycoside tolerance in Escherichia coli but antibiotic resistance gene carriage and NO sensitivity have not co-evolved

2021 ◽  
Author(s):  
Cláudia A. Ribeiro ◽  
Luke A. Rahman ◽  
Louis G. Holmes ◽  
Ayrianna M. Woody ◽  
Calum M. Webster ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Antibiotic Resistance ◽  
Antibiotic Susceptibility ◽  
Bacterial Pathogens ◽  
Antibiotic Resistance Gene ◽  
Antibiotic Resistance Genes ◽  
Resistance Mechanisms ◽  
Current Work ◽  
E Coli ◽  
Respiratory Inhibitor

AbstractThe spread of multidrug-resistance in Gram-negative bacterial pathogens presents a major clinical challenge, and new approaches are required to combat these organisms. Nitric oxide (NO) is a well-known antimicrobial that is produced by the immune system in response to infection, and numerous studies have demonstrated that NO is a respiratory inhibitor with both bacteriostatic and bactericidal properties. However, given that loss of aerobic respiratory complexes is known to diminish antibiotic efficacy, it was hypothesised that the potent respiratory inhibitor NO would elicit similar effects. Indeed, the current work demonstrates that pre-exposure to NO-releasers elicits a > tenfold increase in IC50 for gentamicin against pathogenic E. coli (i.e. a huge decrease in lethality). It was therefore hypothesised that hyper-sensitivity to NO may have arisen in bacterial pathogens and that this trait could promote the acquisition of antibiotic-resistance mechanisms through enabling cells to persist in the presence of toxic levels of antibiotic. To test this hypothesis, genomics and microbiological approaches were used to screen a collection of E. coli clinical isolates for antibiotic susceptibility and NO tolerance, although the data did not support a correlation between increased carriage of antibiotic resistance genes and NO tolerance. However, the current work has important implications for how antibiotic susceptibility might be measured in future (i.e. ± NO) and underlines the evolutionary advantage for bacterial pathogens to maintain tolerance to toxic levels of NO.

Sign in / Sign up

Export Citation Format

Share Document