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Toxins Sep 2021is a clinically important pathogen that causes a wide range of human infections, from minor skin infections to severe tissue infection and sepsis. has a high level of... (Review)
Review
is a clinically important pathogen that causes a wide range of human infections, from minor skin infections to severe tissue infection and sepsis. has a high level of antibiotic resistance and is a common cause of infections in hospitals and the community. The rising prevalence of community-acquired methicillin-resistant (CA-MRSA), combined with the important severity of infections in general, has resulted in the frequent use of anti-staphylococcal antibiotics, leading to increasing resistance rates. Antibiotic-resistant continues to be a major health concern, necessitating the development of novel therapeutic strategies. uses a wide range of virulence factors, such as toxins, to develop an infection in the host. Recently, anti-virulence treatments that directly or indirectly neutralize toxins have showed promise. In this review, we provide an update on toxin pathogenic characteristics, as well as anti-toxin therapeutical strategies.
Topics: Anti-Bacterial Agents; Staphylococcus aureus; Toxins, Biological; Virulence; Virulence Factors
PubMed: 34678970
DOI: 10.3390/toxins13100677 -
Current Opinion in Microbiology Feb 2020Staphylococcus aureus is an opportunistic pathogen that normally colonizes the human anterior nares. At the same time, this pathogen is one of the leading causes of... (Review)
Review
Staphylococcus aureus is an opportunistic pathogen that normally colonizes the human anterior nares. At the same time, this pathogen is one of the leading causes of life-threatening bloodstream infections, such as sepsis and endocarditis. In this review we will present the current understanding of the pathogenesis of these invasive infections, focusing on the mechanisms of S. aureus clearance from the bloodstream by the immune system, and how this pathogen hijacks the host defense and coagulation systems and further interacts with the blood vessel endothelium. Additionally, we will delve into the regulatory mechanisms S. aureus employs during an invasive infection. These new insights into host-pathogen interactions show promising avenues for the development of novel therapies for treating bloodstream infections.
Topics: Animals; Bacteremia; Host-Pathogen Interactions; Humans; Staphylococcal Infections; Staphylococcus aureus; Virulence
PubMed: 32172183
DOI: 10.1016/j.mib.2020.02.005 -
Frontiers in Cellular and Infection... 2014Staphylococcus aureus is a major cause of nosocomial and community-acquired infections and represents a significant burden on the healthcare system. S. aureus attachment... (Review)
Review
Staphylococcus aureus is a major cause of nosocomial and community-acquired infections and represents a significant burden on the healthcare system. S. aureus attachment to medical implants and host tissue, and the establishment of a mature biofilm, play an important role in the persistence of chronic infections. The formation of a biofilm, and encasement of cells in a polymer-based matrix, decreases the susceptibility to antimicrobials and immune defenses, making these infections difficult to eradicate. During infection, dispersal of cells from the biofilm can result in spread to secondary sites and worsening of the infection. In this review, we discuss the current understanding of the pathways behind biofilm dispersal in S. aureus, with a focus on enzymatic and newly described broad-spectrum dispersal mechanisms. Additionally, we explore potential applications of dispersal in the treatment of biofilm-mediated infections.
Topics: Animals; Biofilms; Humans; Staphylococcal Infections; Staphylococcus aureus
PubMed: 25566513
DOI: 10.3389/fcimb.2014.00178 -
Toxins Apr 2021is an opportunistic and versatile pathogen that can cause several diseases, which range from acute and destructive, to chronic and difficult-to-treat infections [...].
is an opportunistic and versatile pathogen that can cause several diseases, which range from acute and destructive, to chronic and difficult-to-treat infections [...].
Topics: Animals; Anti-Bacterial Agents; Drug Resistance; Enterotoxins; Host-Pathogen Interactions; Humans; Staphylococcal Infections; Staphylococcus aureus; Virulence
PubMed: 33921743
DOI: 10.3390/toxins13040287 -
Virulence 2011Increasing attention has been focused on understanding bacterial biofilms and this growth modality's relation to human disease. In this review we explore the genetic... (Review)
Review
Increasing attention has been focused on understanding bacterial biofilms and this growth modality's relation to human disease. In this review we explore the genetic regulation and molecular components involved in biofilm formation and maturation in the context of the Gram-positive cocci, Staphylococcus aureus. In addition, we discuss diseases and host immune responses, along with current therapies associated with S. aureus biofilm infections and prevention strategies.
Topics: Bacterial Physiological Phenomena; Biofilms; Host-Pathogen Interactions; Humans; Models, Biological; Staphylococcal Infections; Staphylococcus aureus
PubMed: 21921685
DOI: 10.4161/viru.2.5.17724 -
International Journal of Nanomedicine 2018() is an important zoonotic bacteria and hazardous for the health of human beings and livestock globally. The characteristics like biofilm forming, facultative... (Review)
Review
() is an important zoonotic bacteria and hazardous for the health of human beings and livestock globally. The characteristics like biofilm forming, facultative intracellular survival, and growing resistance of pose a great challenge to its use in therapy. Nanoparticles are considered as a promising way to overcome the infections' therapeutic problems caused by . In this paper, the present progress and challenges of nanoparticles in the treatment of infection are focused on stepwise. First, the survival and infection mechanism of are analyzed. Second, the treatment challenges posed by are provided, which is followed by the third step including the advantages of nanoparticles in improving the penetration and accumulation ability of their payload antibiotics into cell, inhibiting biofilm formation, and enhancing the antibacterial activity against resistant isolates. Finally, the challenges and future perspective of nanoparticles for infection therapy are introduced. This review will help the readers to realize that the nanosystems can effectively fight against the infection by inhibiting biofilm formation, enhancing intracellular delivery, and improving activity against methicillin-resistant and small colony variant phenotypes as well as aim to help researchers looking for more efficient nano-systems to combat the infections.
Topics: Animals; Anti-Bacterial Agents; Biofilms; Humans; Methicillin-Resistant Staphylococcus aureus; Nanoparticles; Staphylococcal Infections; Staphylococcus aureus
PubMed: 30519018
DOI: 10.2147/IJN.S169935 -
Frontiers in Cellular and Infection... 2015Antibiotic resistance and biofilm-forming capacity contribute to the success of Staphylococcus aureus as a human pathogen in both healthcare and community settings.... (Review)
Review
Antibiotic resistance and biofilm-forming capacity contribute to the success of Staphylococcus aureus as a human pathogen in both healthcare and community settings. These virulence factors do not function independently of each other and the biofilm phenotype expressed by clinical isolates of S. aureus is influenced by acquisition of the methicillin resistance gene mecA. Methicillin-sensitive S. aureus (MSSA) strains commonly produce an icaADBC operon-encoded polysaccharide intercellular adhesin (PIA)-dependent biofilm. In contrast, the release of extracellular DNA (eDNA) and cell surface expression of a number of sortase-anchored proteins, and the major autolysin have been implicated in the biofilm phenotype of methicillin-resistant S. aureus (MRSA) isolates. Expression of high level methicillin resistance in a laboratory MSSA strain resulted in (i) repression of PIA-mediated biofilm production, (ii) down-regulation of the accessory gene regulator (Agr) system, and (iii) attenuation of virulence in murine sepsis and device infection models. Here we review the mechanisms of MSSA and MRSA biofilm production and the relationships between antibiotic resistance, biofilm and virulence gene regulation in S. aureus.
Topics: Animals; Anti-Bacterial Agents; Bacterial Proteins; Biofilms; Gene Expression Regulation, Bacterial; Humans; Methicillin Resistance; Staphylococcal Infections; Staphylococcus aureus
PubMed: 25674541
DOI: 10.3389/fcimb.2015.00001 -
Genes Sep 2021is a bacterium that mainly colonizes the nasal cavity and skin. To colonize the host, it is necessary for to resist many antibacterial factors derived from human and... (Review)
Review
is a bacterium that mainly colonizes the nasal cavity and skin. To colonize the host, it is necessary for to resist many antibacterial factors derived from human and commensal bacteria. Among them are the bacteria-derived antimicrobial peptides (AMPs) called bacteriocins. It was reported that some two-component systems (TCSs), which are signal transduction systems specific to bacteria, are involved in the resistance to several bacteriocins in . However, the TCS-mediated resistance is limited to relatively low concentrations of bacteriocins, while high concentrations of bacteriocins still exhibit antibacterial activity against . To determine whether we could obtain highly bacteriocin-resistant mutants, we tried to isolate highly nisin A-resistant mutants by exposing the cells to sub-minimum inhibitory concentrations (MICs) of nisin A. Nisin A is one of the bacteriocins produced by and is utilized as a food preservative worldwide. Finally, we obtained highly nisin A-resistant mutants with mutations in one TCS, BraRS, and in PmtR, which is involved in the expression of . Notably, some highly resistant strains also showed increased pathogenicity. Based on our findings, this review provides up-to-date information on the role of TCSs in the susceptibility to antibacterial peptides. Additionally, the mechanism for high antimicrobial peptides resistance and its association with pathogenicity in is elucidated.
Topics: Anti-Bacterial Agents; Drug Resistance, Bacterial; Nisin; Staphylococcus aureus; Virulence
PubMed: 34680923
DOI: 10.3390/genes12101527 -
Toxins Jul 2010Staphylococcus aureus produces a wide variety of toxins including staphylococcal enterotoxins (SEs; SEA to SEE, SEG to SEI, SER to SET) with demonstrated emetic... (Review)
Review
Staphylococcus aureus produces a wide variety of toxins including staphylococcal enterotoxins (SEs; SEA to SEE, SEG to SEI, SER to SET) with demonstrated emetic activity, and staphylococcal-like (SEl) proteins, which are not emetic in a primate model (SElL and SElQ) or have yet to be tested (SElJ, SElK, SElM to SElP, SElU, SElU2 and SElV). SEs and SEls have been traditionally subdivided into classical (SEA to SEE) and new (SEG to SElU2) types. All possess superantigenic activity and are encoded by accessory genetic elements, including plasmids, prophages, pathogenicity islands, vSa genomic islands, or by genes located next to the staphylococcal cassette chromosome (SCC) implicated in methicillin resistance. SEs are a major cause of food poisoning, which typically occurs after ingestion of different foods, particularly processed meat and dairy products, contaminated with S. aureus by improper handling and subsequent storage at elevated temperatures. Symptoms are of rapid onset and include nausea and violent vomiting, with or without diarrhea. The illness is usually self-limiting and only occasionally it is severe enough to warrant hospitalization. SEA is the most common cause of staphylococcal food poisoning worldwide, but the involvement of other classical SEs has been also demonstrated. Of the new SE/SEls, only SEH have clearly been associated with food poisoning. However, genes encoding novel SEs as well as SEls with untested emetic activity are widely represented in S. aureus, and their role in pathogenesis may be underestimated.
Topics: Animals; Bacterial Toxins; Enterotoxins; Humans; Staphylococcal Food Poisoning; Staphylococcus aureus; Superantigens
PubMed: 22069659
DOI: 10.3390/toxins2071751 -
Toxins Mar 2016Staphylococcus aureus is an opportunistic pathogen and the leading cause of a wide range of severe clinical infections. The range of diseases reflects the diversity of... (Review)
Review
Staphylococcus aureus is an opportunistic pathogen and the leading cause of a wide range of severe clinical infections. The range of diseases reflects the diversity of virulence factors produced by this pathogen. To establish an infection in the host, S. aureus expresses an inclusive set of virulence factors such as toxins, enzymes, adhesins, and other surface proteins that allow the pathogen to survive under extreme conditions and are essential for the bacteria's ability to spread through tissues. Expression and secretion of this array of toxins and enzymes are tightly controlled by a number of regulatory systems. S. aureus is also notorious for its ability to resist the arsenal of currently available antibiotics and dissemination of various multidrug-resistant S. aureus clones limits therapeutic options for a S. aureus infection. Recently, the development of anti-virulence therapeutics that neutralize S. aureus toxins or block the pathways that regulate toxin production has shown potential in thwarting the bacteria's acquisition of antibiotic resistance. In this review, we provide insights into the regulation of S. aureus toxin production and potential anti-virulence strategies that target S. aureus toxins.
Topics: Animals; Anti-Bacterial Agents; Caenorhabditis elegans; Humans; Staphylococcus aureus; Toxins, Biological; Virulence; Virulence Factors
PubMed: 26999200
DOI: 10.3390/toxins8030072