Pseudomonas aeruginosa biofilms and infections: Roles of extracellular molecules

Pesquisa fenotípica dos fatores de virulência em Pseudomonas aeruginosa isolados de água de abastecimento público

“…Os ramnolipídeos auxiliam nos estágios iniciais da formação de biofilmes e tem papel na regulação da motilidade. A atividade da DNase, demonstrou ser responsável pela redução da viscosidade do escarro em pacientes com fibrose cística [11].…”

“…A protease alcalina tem papel importante na fuga fagocitária e é capaz de degradar um amplo número de proteínas do hospedeiro, incluindo a fibronectina e a laminina, facilitando no processo de invasão da bactéria [10]. Os ramnolipídeos são biosurfactantes que auxiliam nos estágios iniciais da formação de biofilmes e tem papel na regulação da motilidade [11]. A DNase é outro fator de virulência que auxilia a bactéria na fuga de neutrófilos ligados a captura e eliminação de invasores [12].…”

Molecular study among burn patients infected with bacterial pseudomonas species

“…The results of PCR analysis to detected the presence gene of PelA gene (118bp) among of P. aeruginosa 9/10(90%) P.fluorescens 3/4(75%) . P.putadia 3/4(75%),isolates revealed that 15/18 (83.33%) of isolates were contain pelA gene (figure [4][5][6][7][8][9][10][11][12][13][14][15][16][17]. Pseudomonas spp can use either psl or pel as the primary biofilm matrix polysaccharide (Overhage et al, 2005).…”

“…Burns are characterized by severe skin damage that causes the affected skin cells to die (Herndon et al,2018) [4]. The skin is the first immune system and large organ of the body.One of the main functions of the skin is protection as it protects the body from external factors such as microbes, chemicals and temperature (Church et al, 2019) [5]The risk of burn injury are influenced by the types of burn, age of the patient, burn size, burn degree, and other chronic diseases [6]The skin contains gram positive bacteria located in hair follicles and sweat glands as normal flora, the intestine have gram negative bacteria that are normal flora no threat, however in immunosuppression burn patients they spread throughout the body by way of blood stream they can cause infection (Murray and Hospenthal, 2009) [7] Pseudomonas species is a non-spore forming, non-fermentative Gram negative bacilli belong to the pseudomonadaceae family. and most of the cells possess a single polar flagellum (Kiska and Gilligan,1999) [8].The substrates that are known to support its growth ,type IV pili and flagella also have some function in biofilm formationas Type IV pili and flagella negative mutants have different biofilm architecture compared to wild type bacteria (Vasil and Iglewesk, 2008) [9] The alginate in biofilm formation protects from the act of phagocytosis by macrophages, but was not directly involved in attachment and formation of biofilm.…”

Introductory Chapter: Understanding Infections Caused by Opportunistic Bacterial Pathogens

“…These isolates are resistance to many antibiotics (carbapenem, gentamicin, ciprofloxacin, tobramycin, meropenem, and others) which are commonly used to treat infected patients [21][22][23][24]. This bacterium secretes numerous biomolecules such as DNA, proteins, polysaccharides, pyocyanin, rhamnolipids, siderophores which supports them in colonization at infection site and spread virulence in host and shield them from antibacterial agents [25]. In this book, we elaborated on general bacterial biofilm and in specifically focused on mechanism of P. aeruginosa biofilm formation, pathogenicity, antibiotic resistance, and treatment.…”