Characterization of porcine intestinal receptors for the K88ac fimbrial adhesin of Escherichia coli as mucin-type sialoglycoproteins.
We have previously identified two K88ac adhesion receptors (210 and 240 kDa) which are present in membrane preparations from adhesive but not nonadhesive porcine intestinal brush border cells; these adhesin receptors are postulated to be important determinants of the susceptibility of pigs to K88ac+ enterotoxigenic Escherichia coli infections (A.K. Erickson, J.A. Willgohs, S.Y. McFarland, D.A. Benfield, and D.F. Francis, Infect. Immun. 60:983-988, 1992). We now describe a procedure for the purification of these two receptors. Receptors were solubilized from adhesive intestinal brush border vesicles using deoxycholate and were purified by gel filtration chromatography on Sepharose CL-4B and then by hydroxyapatite chromatography. Amino acid compositional analyses indicated that the two receptors have similar amino acid compositions. The most distinguishing characteristic of both receptors is a high percentage of threonine and proline residues. Neuraminidase treatment caused the K88ac adhesin receptors to migrate with a slower mobility on sodium dodecyl sulfate-polyacrylamide gel electrophoresis gels, indicating that these receptors are sialoglycoproteins. Results from lectin-binding studies indicated that the receptors contain O-linked oligosaccharides composed of galactosyl (beta-1,3)N-acetylgalactosamine, alpha-linked fucose, galactosyl(beta-1,4)N-acetylglucosamine, sialic acid, galactose, and N-acetylgalactosamine. Collectively, these characteristics indicate that the K88ac adhesin receptors are mucin-type sialoglycoproteins.
Erickson
A K
AK
Department of Veterinary Science, South Dakota State University, Brookings 57007.
Baker
D R
DR
Bosworth
B T
BT
Casey
T A
TA
Benfield
D A
DA
Francis
D H
DH
D000596:Amino Acids / Q000032:analysis; D000818:Animals; D000942:Antigens, Bacterial; D000954:Antigens, Surface / Q000276:immunology; D001422:Bacterial Adhesion / Q000502:physiology; D002240:Carbohydrate Sequence; D002241:Carbohydrates / Q000737:chemistry; D004926:Escherichia coli / Q000276:immunology*; D029968:Escherichia coli Proteins; D036781:Fimbriae Proteins; D010861:Fimbriae, Bacterial / Q000276:immunology; D007422:Intestines / Q000737:chemistry*; D037102:Lectins / Q000378:metabolism; D008871:Microvilli / Q000737:chemistry; D008969:Molecular Sequence Data; D009077:Mucins / Q000737:chemistry*; D011971:Receptors, Immunologic / Q000737:chemistry* / Q000302:isolation & purification; D012795:Sialoglycoproteins / Q000737:chemistry* / Q000145:classification; D013552:Swine
D000596:Amino Acids; D000942:Antigens, Bacterial; D000954:Antigens, Surface; D002241:Carbohydrates; D029968:Escherichia coli Proteins; C026888:K88 antigen, E coli; D037102:Lectins; D009077:Mucins; D011971:Receptors, Immunologic; D012795:Sialoglycoproteins; C047105:bacterial adhesin receptor; D036781:Fimbriae Proteins