Binding of collagens to an enterotoxigenic strain of Escherichia coli
- Univ. of Pavia (Italy)
An enterotoxigenic strain of Escherichia coli, B34289c, has been shown to bind the N-terminal region of fibronectin with high affinity. We now report that this strain also binds collagen. The binding of 125I-labeled type II collagen to bacteria was time dependent and reversible. Bacteria expressed a limited number of collagen receptors (2.2 x 10(4) per cell) and bound collagen with a Kd of 20 nM. All collagen types tested (I to V) as well as all tested cyanogen bromide-generated peptides (alpha 1(I)CB2, alpha 1(I)CB3, alpha 1(I)CB7, alpha 1(I)CB8, and alpha 2(I)CB4) were recognized by bacterial receptors, as demonstrated by the ability of these proteins to inhibit the binding of 125I-labeled collagen to bacteria. Of several unlabeled proteins tested in competition experiments, fibronectin and its N-terminal region strongly inhibited binding of the radiolabeled collagen to E. coli cells. Conversely, collagen competed with an 125I-labeled 28-kilodalton fibronectin fragment for bacterial binding. Collagen bound to bacteria could be displaced by excess amounts of either unlabeled fibronectin or its N-terminal fragment. Similarly, collagen could displace 125I-labeled N-terminal peptide of fibronectin bound to the bacterial cell surface. Bacteria grown at 41 degrees C or in the presence of glucose did not express collagen or fibronectin receptors. These results indicate the presence of specific binding sites for collagen on the surface of E. coli cells and furthermore that the collagen and fibronectin binding sites are located in close proximity, possibly on the same structure.
- OSTI ID:
- 6995246
- Journal Information:
- Infection and Immunity; (USA), Journal Name: Infection and Immunity; (USA) Vol. 58:2; ISSN 0019-9567; ISSN INFIB
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
59 BASIC BIOLOGICAL SCIENCES
BACTERIA
BETA DECAY RADIOISOTOPES
BIOCHEMICAL REACTION KINETICS
BIOLOGICAL LOCALIZATION
COLLAGEN
DAYS LIVING RADIOISOTOPES
ELECTRON CAPTURE RADIOISOTOPES
ESCHERICHIA COLI
INTERMEDIATE MASS NUCLEI
IODINE 125
IODINE ISOTOPES
ISOTOPE APPLICATIONS
ISOTOPES
KINETICS
MEMBRANE PROTEINS
MICROORGANISMS
NUCLEI
ODD-EVEN NUCLEI
ORGANIC COMPOUNDS
PROTEINS
RADIOISOTOPES
REACTION KINETICS
RECEPTORS
SCLEROPROTEINS
TIME DEPENDENCE
TRACER TECHNIQUES