Adhesins
Adhesins are surface proteins or molecules found in bacteria and other microorganisms that enable them to adhere to host cells or tissues. They play a crucial role in the initial stages of infection by facilitating the attachment of the pathogen to the host, which is a key step in the establishment of infection. Adhesins are important targets for developing strategies to prevent and treat infections.
4 Key excerpts on "Adhesins"
eBook - ePub- Mahmoud Ghannoum, Matthew Parsek, Marvin Whiteley, Pranab K. Mukherjee, Mahmoud Ghannoum, Matthew Parsek, Marvin Whiteley, Pranab K. Mukherjee(Authors)
- 2015(Publication Date)
- ASM Press(Publisher)
...The recent advances in our understanding of the secretion, assembly, and regulation of these bacterial Adhesins demonstrate that, even if they share some key structural and regulatory factors that determine their expression at the surface of cells, their level of specificity varies significantly depending on the targeted surface. This characteristic clearly illustrates the ability of bacteria to successfully adapt and adhere to virtually all natural and man-made materials. This article reviewed major protein and localized discrete polysaccharide Adhesins, but the large variety of Adhesins suggests that virtually any biological molecule made by the bacterium can be used to support or modulate its adhesion to surfaces. Even previously unsuspected biological molecules, such as extracellular DNA and lipids, have been shown to play a role in the process of adhesion or biofilm maturation (193, 194). Recent discoveries in the regulation and the modulation of adhesion suggest that this process is much more complex and dynamic than originally anticipated. We have just begun to understand the factors that govern the temporal regulation of the expression of adhesin molecules, but many questions concerning the nature of signals triggering the secretion of the proper adhesin or the interaction between the different types of Adhesins remain unanswered. The recent advent of single-cell approaches will yield a better understanding of the detailed roles of each adhesive factor and the environment during this transition from reversible to irreversible attachment (195). Surprisingly, even with decades of research, the exact molecular mechanisms that support or modulate the interaction between Adhesins and surfaces have seldom been characterized...
eBook - ePub- Jiri Mestecky, Michael E. Lamm, Pearay L. Ogra, Warren Strober, John Bienenstock, Jerry R. McGhee, Lloyd Mayer(Authors)
- 2005(Publication Date)
- Academic Press(Publisher)
...Several activities that are intimately related to the infectious process have emerged that are so-called adhesion-dependent or are immediate consequences of adhesion (reviewed in Finlay and Cossart 1997 ; Wullt et al. 2002). Apparently, the specific interaction between bacterial Adhesins and their complementary receptors on mucosal cells elicits a variety of distinct responses in the host cells as well as in the bacteria, which can markedly affect the course of the infectious process. These findings point to some intriguing and novel functions for bacterial Adhesins on mucosal surfaces as well as in deeper tissue. This section reviews evidence of selected examples of bacterial adhesin-mediated responses in the bacteria and in various host cells and their contribution to the infectious process. Since many of these observations involve uropathogenic E. coli, we will examine the implications of these findings in the context of the urinary tract wherever pertinent. Induction of bacterial virulence genes The urinary tract is relatively inhospitable to bacterial colonization. To establish an infection, bacteria must be able to sense this hostile environment and to modulate its protein expression profile to ensure their survival. There is now evidence that the bacteria can do so by using their Adhesins as sensory organelles. It has been shown that host cell contact by the P fimbriae of E. coli can induce the CPX two-component signal transduction system, which has been shown to alter virulence gene transcription such as the Pap gene cluster (Hung et al. 2001 ; reviewed in Raivio and Silhavy 1999). These findings point to an intriguing new function for bacterial P fimbriae, namely, that of a sensory organelle. The strategic location of PapG at the distal tips of the peritrichously arranged fimbriae probably facilitates this purported role...
eBook - ePub- Vincent A. Fischetti, Richard P. Novick, Joseph J. Ferretti, Daniel A. Portnoy, Mirian Braunstein, Julian I. Rood, Vincent A. Fischetti, Richard P. Novick, Joseph J. Ferretti, Daniel A. Portnoy, Mirian Braunstein, Julian I. Rood(Authors)
- 2019(Publication Date)
- ASM Press(Publisher)
...The role of Staphylococcus aureus Adhesins in the pathogenesis of ventricular assist device-related infections. J Infect Dis 193 : 1109–1119. [CrossRef] [PubMed] 170. Rhem MN, Lech EM, Patti JM, McDevitt D, Höök M, Jones DB, Wilhelmus KR. 2000. The collagen-binding adhesin is a virulence factor in Staphylococcus aureus keratitis. Infect Immun 68 : 3776–3779. [CrossRef] [PubMed] 171. Patel AH, Nowlan P, Weavers ED, Foster T. 1987. Virulence of protein A-deficient and alpha-toxin-deficient mutants of Staphylococcus aureus isolated by allele replacement. Infect Immun 55 : 3103–3110. 172. Palmqvist N, Foster T, Tarkowski A, Josefsson E. 2002. Protein A is a virulence factor in Staphylococcus aureus arthritis and septic death. Microb Pathog 33 : 239–249. [CrossRef] [PubMed] 173. Patti JM, Bremell T, Krajewska-Pietrasik D, Abdelnour A, Tarkowski A, Rydén C, Höök M. 1994. The Staphylococcus aureus collagen adhesin is a virulence determinant in experimental septic arthritis. Infect Immun 62 : 152–161. 174. Dastgheyb S, Parvizi J, Shapiro IM, Hickok NJ, Otto M. 2015. Effect of biofilms on recalcitrance of staphylococcal joint infection to antibiotic treatment. J Infect Dis 211 : 641–650. [CrossRef] [PubMed] 175. Kwiecinski J, Jin T, Josefsson E. 2014. Surface proteins of Staphylococcus aureus play an important role in experimental skin infection. APMIS 122 : 1240–1250. [CrossRef] [PubMed]...
eBook - ePub- Hongbo Zeng(Author)
- 2013(Publication Date)
- Wiley(Publisher)
...Once the bacteria come close enough to the surface (<3 nm), acid–base bonding, hydrogen bonding, ionic, and dipole interactions governed by the macroscopic surface properties such as hydrophobicity and surface charge dominate the adhesion [8, 17]. The net sum of attractive and repulsive forces generated between the bacterium and the surface dominates the strength of bacterial adhesion [18]. Because most bacteria and inert surfaces are negatively charged [19], repulsions are electrostatically favored. Attractive or repulsive hydrophobic interactions are important due to their polar origin and can be up to two orders of magnitude higher than van der Waals or electrostatic forces [14, 20–21]. In the second stage, bacteria consolidate the adhesion by secreting specific Adhesins such as exopolysaccharides [22], proteins [23], pili or fimbriae [24], and flagella [25]. The term “exopolysaccharides” mainly refers to extracellular polymeric substances (EPS) and lipopolysaccharides (LPS). Their compositions and amount are variable depending on the environment conditions [26]. As a result, the interactions previously described are significantly affected by various environmental parameters such as salts, pH, temperature, and soluble sugar [17]. Besides them, there is another type of interaction that is less influenced by environment and seems to be selective. This is the so-called specific interaction, and which can only exhibit between specific bacterial surface Adhesins and the corresponding substratum receptors (antigens and antibodies, carbohydrates and lectins, and substrates and enzymes) [8, 27]. 14.2 THE IMPACT OF BACTERIAL SURFACE POLYMERS ON BACTERIAL ADHESION 14.2.1 Bacterial Surface Polymers Bacterial cells are gram positive or gram negative based on cell wall structures...
