Transferrin associated with the porcine intestinal mucosa is a receptor specific for K88ab fimbriae of Escherichia coli

Abstract

Putative receptors of Escherichia coli K88 fimbriae are either tightly membrane bound or an integral part of membranes. Thus, proteins associated with piglet small intestinal mucosae were solubilized by a detergent (deoxycholate). A 74-kDa glycoprotein (GP74) purified from enterocyte and brush border membrane preparations was specifically detected in vitro by K88ab fimbriae. GP74 was recognized only in the mucosae of phenotypically adhesive animals. Metaperiodate treatment abolished the recognition, indicating that K88ab fimbriae-GP74 binding required the carbohydrate moiety. This glycoprotein belongs to the transferrin family and differed from the serum transferrin of the same adhesive-phenotype piglets. Unlike intestinal transferrin, serum transferrin was recognized independently of the adhesion phenotype. The glycan moieties of intestinal and serum transferrins differed in their molar compositions. Transferrin GP74 contained one monosialylated and monofucosylated glycan chain of the N-acetyllactosamine type. Intestinal holotransferrin exhibited pI values of 5.2, 5.3, 5.5, and 5.6, whereas serum holotransferrin pI values ranged between 5.4 and 6.2. Since mucosal transferrin was found intimately entrapped on membranes, we hypothesize that a K88ab fimbriaetransferrin-cell transferrin receptor complex might allow the bacteria to adhere to specific sites of the mucosa.

Interleukin-17A/F1 Deficiency Reduces Antimicrobial Gene Expression and Contributes to Microbiome Alterations in Intestines of Japanese medaka (Oryzias latipes)

“…Transferrin a is an iron ion transporter and an important factor in homeostasis maintenance, in which the iron ion absorption effect is known to attenuate bacterial proliferation. Transferrin a is also abundant in mucosal tissues and considered to inhibit bacterial survival (32,33). Moreover, the transferrin gene has been identified in several fish species, including the Japanese medaka, and is known to be induced at the transcriptional level upon bacterial infection stress (34)(35)(36).…”

Characterization of polymorphisms of transferrin receptor and their association with susceptibility to ETEC F4ab/ac in pigs

“…The locus controlling susceptibility towards ETEC F4 strains ab and ac (F4ab/ac) has been consistently mapped to pig chromosome (SSC) 13q41 (Python et al 2002;Jørgensen et al 2003), and the positional candidate genes are most likely those coding for some transferrins or mucin-like sialoglycoproteins (Grange & Mouricout 1996;Grange et al 1998Grange et al , 2002. Transferrin receptor (TFRC) was assigned to SSC13q41 by radiation hybrid mapping (Van Poucke et al 2001), and was hence considered as a positional candidate gene for ETEC F4ab/ac receptor (Python et al 2005).…”

Characterization of the Carbohydrate Moiety of Intestinal Mucin-Type Sialoglycoprotein Receptors for the K88ac Fimbrial Adhesin of Escherichia coli

“…Many research groups have reported the identification of putative K88 fimbrial adhesin receptors in both intestinal brush border (9,12,17,19,35) and intestinal mucus (5,19,21,37) preparations. In contrast to many of the other K88 receptors identified, IMTGP-1 and IMTGP-2 are detected only in adhe-sive phenotypes of pigs; consequently, it is very likely that these receptors are important in the in vivo attachment of K88ab and K88ac ETEC to porcine intestine (4,8,9,28).…”