Biomaterial Database

Identification of factors in human urine that inhibit the binding of Escherichia coli adhesins. 1988

J Parkkinen, and R Virkola, and T K Korhonen

Department of Medical Chemistry, University of Helsinki, Finland.

Earlier studies on the binding of Escherichia coli adhesins to the human urinary tract have indicated that the ability to recognize binding sites on the urinary tract epithelial cells is not a characteristic for P fimbriae only, but is also shared by some other adhesins that are not associated with pyelonephritis, especially S fimbriae. In the present study we have investigated whether human urine contains inhibitors of the binding of E. coli adhesins. Normal human urine was found to inhibit hemagglutination by S and type 1 fimbriae but not P fimbriae. The major inhibitor of S fimbriae in normal urine was identified as Tamm-Horsfall glycoprotein, and the interaction with S fimbriae is probably mediated by its sialyloligosaccharide chains. No significant variation was observed in the inhibitory effect of T-H glycoprotein preparations originating from different individuals. In contrast to S fimbriae, the major inhibitors of type 1 fimbriae in urine were identified as low-molecular-weight compounds. Gel filtration and ion-exchange chromatography and alpha-mannosidase treatment indicated that they were neutral alpha-mannosides, probably manno-oligosaccharides with three to five saccharides. Studies of urine samples collected from several individuals indicated the common occurrence of these inhibitory alpha-mannosides. Type 1 fimbriae bound to immobilized T-H glycoprotein, but, unlike S fimbriae, their binding was poorly inhibited by soluble T-H glycoprotein. Some urine samples were also found to contain low-molecular-weight inhibitors for the O75X adhesin of E. coli. These results emphasize that to function as a virulence factor in human urinary tract infections, an adhesin must evidently recognize such receptor structures at the infection sites that are not excreted in soluble form in urine. This prerequisite is filled by P fimbriae but not by type 1 or S fimbriae.

UI	MeSH Term	Description	Entries
D008970	Molecular Weight	The sum of the weight of all the atoms in a molecule.	Molecular Weights,Weight, Molecular,Weights, Molecular
D009088	Mucoproteins	Conjugated proteins in which mucopolysaccharides are combined with proteins. The mucopolysaccharide moiety is the predominant group with the protein making up only a small percentage of the total weight.
D010861	Fimbriae, Bacterial	Thin, hairlike appendages, 1 to 20 microns in length and often occurring in large numbers, present on the cells of gram-negative bacteria, particularly Enterobacteriaceae and Neisseria. Unlike flagella, they do not possess motility, but being protein (pilin) in nature, they possess antigenic and hemagglutinating properties. They are of medical importance because some fimbriae mediate the attachment of bacteria to cells via adhesins (ADHESINS, BACTERIAL). Bacterial fimbriae refer to common pili, to be distinguished from the preferred use of "pili", which is confined to sex pili (PILI, SEX).	Bacterial Fimbriae,Bacterial Pili,Common Fimbriae,Common Pili,Pili, Bacterial,Pili, Common,Bacterial Fimbria,Bacterial Pilus,Common Fimbria,Common Pilus,Fimbria, Bacterial,Pilus, Bacterial,Fimbria, Common,Fimbriae, Common,Pilus, Common
D011485	Protein Binding	The process in which substances, either endogenous or exogenous, bind to proteins, peptides, enzymes, protein precursors, or allied compounds. Specific protein-binding measures are often used as assays in diagnostic assessments.	Plasma Protein Binding Capacity,Binding, Protein
D004926	Escherichia coli	A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc.	Alkalescens-Dispar Group,Bacillus coli,Bacterium coli,Bacterium coli commune,Diffusely Adherent Escherichia coli,E coli,EAggEC,Enteroaggregative Escherichia coli,Enterococcus coli,Diffusely Adherent E. coli,Enteroaggregative E. coli,Enteroinvasive E. coli,Enteroinvasive Escherichia coli
D006384	Hemagglutination	The aggregation of ERYTHROCYTES by AGGLUTININS, including antibodies, lectins, and viral proteins (HEMAGGLUTINATION, VIRAL).	Hemagglutinations
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D001422	Bacterial Adhesion	Physicochemical property of fimbriated (FIMBRIAE, BACTERIAL) and non-fimbriated bacteria of attaching to cells, tissue, and nonbiological surfaces. It is a factor in bacterial colonization and pathogenicity.	Adhesion, Bacterial,Adhesions, Bacterial,Bacterial Adhesions
D001425	Bacterial Outer Membrane Proteins	Proteins isolated from the outer membrane of Gram-negative bacteria.	OMP Proteins,Outer Membrane Proteins, Bacterial,Outer Membrane Lipoproteins, Bacterial
D014556	Urine	Liquid by-product of excretion produced in the kidneys, temporarily stored in the bladder until discharge through the URETHRA.