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Bacterial Adherence to Cell Surface Sugars
Abstract
Bacterial adherence to animal cell surfaces is of interest because of its relation to pathogenicity and the insight it provides into determinants of intercellular recognition. The attachment of various strains of Escherichia coli and Salmonella spp. to epithelial cells and phagocytes is inhibited by D-mannose, and the adherence of other bacteria is inhibited by sugars such as L-fucose and D-galactose, suggesting that sugar-mediated adherence is widespread. This intercellular recognition is thought to be mediated by sugar residues (e.g. D-mannose) on the surface of animal cells, to which bacteria attach by a sugar-binding substance on their surface. The nature of the receptors on the animal cells is unknown. There is evidence that E. coli produces lectin-like substances specific for D-mannose, by which it binds to the cells. The most common form of these lectin-like substances appears to be the bacterial pili, which can be reversibly dissociated into their protein subunits. The lectin can also be in the form of bacterial flagella or tightly attached to the outer membrane of the bacteria. Mannose-specific attachment may assist bacteria in colonizing and invading their hosts: methyl alpha-D-mannoside (but not methyl alpha-D-glucoside) significantly reduced infection of the urinary tract of mice by virulent strains of E. coli. Once bacteria penetrate the host their ability to binding sugars on phagocytes may impair their virulence by facilitating phagocytosis. Further studies of the sugar-mediated bacterial adherence by organisms growing in vivo and the structural identification of the host cell receptors may lead to the design of more effective adherence inhibitors that may help to prevent certain bacterial infections.
... Finally, detailed evaluation of the results obtained for the biogenic aerosol particles with diameters exceeding 10 µm revealed correlations between bacteria and saccharides such as mannose and trehalose (Fig. S4). Mannose is used by bacteria as a lectin-like substance to bind to cells, and may also find its way to aerosol particles (Sharon et al., 1981). Additionally, correlations were found between bacteria and some important AAs in the Krebs cycle. ...
Primary biological aerosol particles (PBAPs) play an important role in the interaction between biosphere, atmosphere, and climate, affecting cloud and precipitation formation processes. The presence of pollen, plant fragments, spores, bacteria, algae, and viruses in PBAPs is well known. In order to explore the complex interrelationships between airborne and particulate chemical tracers (amino acids, saccharides), gene copy numbers (16S and 18S for bacteria and fungi, respectively), gas phase chemistry, and the particle size distribution, 84 size-segregated aerosol samples from four particle size fractions ( 10 µm) were collected at the SMEAR II station, Finland, in autumn 2017. The gene copy numbers and size distributions of bacteria, Pseudomonas, and fungi in biogenic aerosols were determined by DNA extraction and amplification. In addition, free amino acids (19) and saccharides (8) were analysed in aerosol samples by hydrophilic interaction liquid chromatography–mass spectrometry (HILIC-MS). Different machine learning (ML) approaches, such as cluster analysis, discriminant analysis, neural network analysis, and multiple linear regression (MLR), were used for the clarification of several aspects related to the composition of biogenic aerosols. Clear variations in composition as a function of the particle size were observed. In most cases, the highest concentration values and gene copy numbers (in the case of microbes) were observed for 2.5–10 µm particles, followed by > 10, 1–2.5, and
... Flagella protruding from the surface of E. coli cells represent a target of the host's immune system. Flagellated E. coli cells are more likely to be phagocytized than no-flagellated cells [52] . E. coli that have reached the kidneys would be in a low pH/high-osmolarity environment where the flagella are no longer needed and may in fact be a detriment to their survival. ...
Background:
Escherichia coli (E. coli) express flagella to ascend human urinary tracts. To survive in the acidic pH of human urine, E. coli uses the glutamate decarboxylase acid response system, which is regulated by the GadE protein.
Aim:
To determine if growth in an acidic pH environment affected fliC transcription and whether GadE regulated that transcription.
Methods:
A fliC-lacZ reporter fusion was created on a single copy number plasmid to assess the effects of acidic pH on fliC transcription. Further, a ΔgadE mutant strain of a uropathogenic E. coli was created and tested for motility compared to the wild-type strain.
Results:
Escherichia coli cells carrying the fliC-lacZ fusion displayed significantly less fliC transcription when grown in an acidic pH medium compared to when grown in a neutral pH medium. Transcription of fliC fell further when the E. coli was grown in an acidic pH/high osmolarity environment. Since GadE is a critical regulator of one acid response system, fliC transcription was tested in a gadE mutant strain grown under acidic conditions. Expression of fliC was derepressed in the E. coli gadE mutant strain grown under acidic conditions compared to that in wild-type bacteria under the same conditions. Furthermore, a gadE mutation in a uropathogenic E. coli background exhibited significantly greater motility than the wild-type strain following growth in an acidic medium.
Conclusion:
Together, our results suggest that GadE may down-regulate fliC transcription and motility in E. coli grown under acidic conditions.
... As discussed above, oligosaccharide receptors or glycoproteins expressing defined oligosaccharide epitopes are secreted into the urine and act as competitive inhibitors of bacterial attachment (178). Original observations on mannose-mediated inhibition of infection were made by Aronson et al. ...
... Alpha D-Mannose, L-fucose and N-Acetylgalactosamine, which present in the lumen of the excretory duct of glands of quills of the porcupine, are known as a part of glycoprotein, which can inhibit the adherence of some bacteria and fungi to the surface epidermal cells (Sharon et al. 1981;McGavin et al. 1993;Ollert et al. 1993;Critchley and Douglas 1987). PHAE and PHAL are the lectins, which bind specifically for oligosaccharide of complex-type N-glycan (Hirabayashi et al. 2011;Gabius et al. 2011). ...
Prawira AY, Novelina S, Farida WR, Darusman HS, Agungpriyono S. 2019. Lectin histochemical study of the quill sebaceous gland in the dorsal skin of the Sunda porcupine (Hystrix javanica). Biodiversitas 20: 2677-2684. In the Sunda Porcupine skin, the sebaceous glands of the quill follicles are multi-lobed alveolar and better developed than those of hair follicles. Using lectin histochemistry, we have studied the distribution of sugar-binding in the sebaceous glands of quills in comparison with those of hairs in six adult Sunda Porcupines. The skin samples from the thoracodorsal and lumbosacral regions were collected by biopsy procedure and processed for histology, histochemistry, and lectin histochemistry. The results showed that the lectin binding patterns are similar in secretory acinar parts of both types of sebaceous glands. The acini and excretory duct contained neutral carbohydrate and sugar residues. The acini also contained alpha D-mannose sugar residue, while the non-secretory excretory duct and debris in the lumen contained alpha-D-mannose, alpha-L-fucose, and α>β-N-acetylgalactosamine, and complex type N-glycan (oligosaccharide) sugar residues, as well. The present findings allowed us to suggest, that in Sunda Porcupine functions of the sebaceous glands of quills are more complex and active compared to those of the hairs.
... FITC-lectin labeling is one of the best tools for localizing surface carbohydrates and sugar ligands on cell surfaces. Sugar residues on the surface of host cells are related to cellular phagocytosis and the binding and invasion of pathogens (Sharon et al. 1981, Roy and Mandal 2016, Szymanski et al. 2017. A set of fluorescent lectins was previously used in the Ae. ...
The mosquito gut is divided into foregut, midgut, and hindgut. The midgut functions in storage and digestion of the bloodmeal. This study used light, scanning (SEM), and transmission (TEM) electron microscopy to analyze in detail the microanatomy and morphology of the midgut of nonblood-fed Anopheles aquasalis females. The midgut epithelium is a monolayer of columnar epithelial cells that is composed of two populations: microvillar epithelial cells and basal cells. The microvillar epithelial cells can be further subdivided into light and dark cells, based on their affinities to toluidine blue and their electron density. FITC-labeling of the anterior midgut and posterior midgut with lectins resulted in different fluorescence intensities, indicating differences in carbohydrate residues. SEM revealed a complex muscle network composed of circular and longitudinal fibers that surround the entire midgut. In summary, the use of a diverse set of morphological methods revealed the general microanatomy of the midgut and associated tissues of An. aquasalis, which is a major vector of Plasmodium spp. (Haemosporida: Plasmodiidae) in America.
Saccharomyces boulardii is a yeast clinically used for treating various symptoms of gastrointestinal dysbiosis. Despite their genomic relatedness, S. boulardii has a distinctive cell wall oligosaccharide composition compared to baker's yeast S. cerevisiae, such as higher mannan content. Here we explore the beneficial effects of S. boulardii cell wall oligosaccharides through metabolic engineering. We increased the production of guanosine diphosphate (GDP)-mannose, the substrate for cell wall mannan biosynthesis, by perturbing glycolysis flux and overexpressing the enzymes in the GDP-mannose biosynthesis pathway. Combined with overexpression of a cell wall mannoprotein and dolichol phosphate mannose synthase, the cell wall mannan content of S. boulardii increased up to 52%. The identical engineering resulted in marginal changes in the S. cerevisiae cell wall. S. boulardii showed a higher adhesive capacity against Salmonella enterica Typhimurium than S. cerevisiae, and yeast-bacteria sedimentation rates were positively correlated with cell wall mannan contents. Besides, S. boulardii biomass selectively proliferated Bacteroides thetaiotaomicron over Clostridioides difficile more efficiently than S. cerevisiae, and the selectivity was further enhanced by amplifying the cell wall mannan. Collectively, we report the important prebiotic roles of cell wall oligosaccharides in the protective functions of S. boulardii and present a unique metabolic engineering approach to modulate the functions.
The object of this review is the genus Proteus, which contains bacteria considered now to belong to the opportunistic pathogens. Widely distributed in nature (in soil, water, and sewage), Proteus species play a significant ecological role. When present in the niches of higher macroorganisms, these species are able to evoke pathological events in different regions of the human body. The invaders (Proteus mirabilis, P. vulgaris, and P. penneri) have numerous factors including fimbriae, flagella, outer membrane proteins, lipopolysaccharide, capsule antigen, urease, immunoglobulin A proteases, hemolysins, amino acid deaminases, and, finally, the most characteristic attribute of Proteus, swarming growth, enabling them to colonize and survive in higher organisms. All these features and factors are described and commented on in detail. The questions important for future investigation of these facultatively pathogenic microorganisms are also discussed.
Bacterial infections of the uterus are the leading cause of subfertility and infertility in mares and represent a major economic loss to the equine industry.
Several important properties of the common pili from Escherichia coli are discussed. These pili were resistant to the gentle Folin-Ciocalteau reagent methods for protein detection and were not readily solubilized by sodium dodecyl sulfate. They were found to contain a reducing sugar but not peptidoglycan. The pilin had multiple conformations in sodium dodecyl sulfate solution, and the appearance of multiple bands on sodium dodecyl sulfate gels did not necessarily indicate heterogeneity of the preparation. The ilus subunit was found to be a different protein than outer membrane III, which has the same apparent molecular weight. In addition, we conformed the results of Brinton (Trans. N.Y. Acad. Sci 27:1003-1054, 1965): that there is a dramatic change in the properties of pili after they are heated at pH values below 2.
THE colonisation of bacteria on human mucosal tissues is now recognised as an important step in the infectious process1,2. To colonise mucosal surfaces, the organisms must first bind to the epithelial cells of these tissues, or they are discarded by the host's physico-anatomical defence mechanism (sneezing, coughing, urine flush and so on). The attachment of bacteria to epithelial cells can be demonstrated in vitro3,4 and is probably mediated by surface components of both types of cell5. It was found4,5 that lipoteichoic acid on the surface of group A streptococci is responsible for the attachment of these organisms to oral mucosal cells. For Gram negative organisms, pili mediate their binding to epithelial cells6-9. In a study with Proteus mirabilis it was found10 that the presence of pili is important for the organisms to adhere to both oral and bladder mucosal cells as well as to initiate retrograde infection in experimental animals, probably by enabling the bacteria to adhere and to colonise pelvic epithelial cells11. Nothing is known, however, about the putative receptor sites required for bacterial attachment on the mucosal cell membrane. We present here data indicating that attachment of Escherichia coli to epithelial cells is mediated by mannose (or mannose-like) receptors present on the surface of the latter.
Living organisms abound in a large variety of proteins that possess the ability to specifically bind different compounds. Most important among these are the enzymes that combine specifically with the substrates and inhibitors, and antibodies that bind antigens. A third class of proteins with specific combining sites, found mainly in plants, has recently moved to the forefront of biologic research; these are lectins. The main characteristics of lectins are their ability to bind sugars, to agglutinate cells, and to stimulate lymphocytes. In all their activities, lectins exhibit varying degrees of specificity. Most lectins interact preferentially with a single sugar structure. For some lectins, the specificity is broader and includes a number of closely related sugars; whereas certain lectins interact only with complex carbohydrate structures. Through their sugar-combining sites, lectins interact specifically with polysaccharides and glycoproteins to form precipitates. This reaction is similar to the precipitin reaction between antibody and antigen, in that it is specific, exhibits concentration dependence on lectin and polysaccharide, and might be inhibited specifically by low molecular weight “haptens”—compounds identical with or derived from the sugar(s) for which, the lectin is specific. Therefore, lectins are similar to antibodies in many respects.
A review of the chemotherapy of infectious disease and relevant accomplishments over the first half of the twentieth century. Keywords (Audience): General PublicKeywords (Domain): History / PhilosophyKeywords (Feature): Symposium ReportKeywords (Subject): Medicinal Chemistry
Adherence of Escherichia coli to D-mannose-like residues on epithelial cells may be an important step in bacterial infection. This raises the possibility of using simple sugars, such as methyl α-D-mannoside in the prevention of infection by certain gram-negative bacteria.
The entero-pathogenic strain ofE. coli 0125: K 70 was able to adhere to washed guinea-pig erythrocytes and to cause their agglutination. Electron microscopy revealed this strain to be rich in fimbriae. They were able to cause hemagglutination by themselves, generally at protein concentration of 10 to 100 g per ml.d-mannose and -methylmannoside were able to inhibit hemagglutination by the whole bacteria or their isolated fimbriae at concentrations of 0.003 to 0.012 mg/ml.l-mannose,d-lactose,d-glucose, N-acetylglucosamine,d-galactose, N-acetyl-d-galactosamine,d-fucose, did not exert any inhibiting effect at concentrations as high as 50 mg/ml. N-acetyl-neuraminic acid was also uneffective at concentration as high as 9 mg/ml.
We have demonstrated binding of purified pili from a strain of Escherichia coli to Vero cell monolayers as a model of prokaryotic-eukaryotic cell adherence. Pili bound to the tissue culture in a rapid reaction that did not require enzymatic activation. Attachment occurred optimally at pH 4-5 and could be inhibited by analogues of D-mannose, anti-pili antibodies, or by preincubation of tissue cells with mannose-specific plant lectins. Binding remained after treatment of the monolayer with glycosidases, trypsin, or a protease mixture but was enhanced after neuraminidase treatment. These results indicate that bacterial binding can occur via pili which act like lectins and presumably bind to mannose-containing glycoproteins on mammalian cell surfaces.
Human A, B, and O erythrocytes (RBC) were agglutinated by many human strains of Actinomyces viscosus and A. naeslundii. At 37 degrees C, these bacterium-mediated hemagglutination reactions required the action of bacterial neuraminidase upon the RBC; however, at 4 degrees C, the requirement for neuraminidase was not as striking. Bacterial cell suspensions which caused hemagglutination at 37 degrees C contained both soluble extracellular and cell-associated neuraminidase activities as shown by enzyme assays using a soluble substrate (i.e., alpha 1-acid glycoprotein). Bacterium-mediated hemagglutination occurred only in the presence of soluble neuraminidase activity, and the rate of hemagglutination could be inhibited by 2-deoxy-2,3-dehydro-N-acetylneuraminic acid, a competitive inhibitor of purified soluble neuraminidase from A. viscosus T14V. Suspensions of bacteria which contained only cell-associated neuraminidase activity were unable to initiate hemagglutination, but they caused immediate hemagglutination when mixed with neuraminidase-treated RBC. All hemagglutination reactions were reversible in the presence of 0.02 M lactose and were abolished by heating (85 degrees C for 30 min) the actinomycete cells but not the RBC. The proposed mechanism of hemagglutination involves two sequential steps: (i) the action of neuraminidase to unmask galactose-containing receptors on the RBC and (ii) the multivalent binding of these receptors by many low-affinity lection sites on the bacterial surface.