Amino Acid Composition of Mannose - Sensitive ( SH 48 ) and Gal - Gal Binding ( HU 849 )

Two major classes of chromosomally encoded Escherichia coli pili have been defined functionally by their receptor specificities. Common pili are termed "mannose-sensitive" (MS). They bind Tamm-Horsfal l uromucoid and their agglutination of guinea pig erythrocytes is inhibited by o-mannose. In contrast, mannose-resistant (MR) pili agglutinate human erythrocytes in the presence of D-mannose. Most human pyelonephritis E. coli isolates express MR pili that bind neutral glycosphingolipid constituents of uroepithelial cells (1). They contain oGal p o~1 ---* 4 D-Gal p 131 and a synthetic analogue of this disaccharide (Syn GalGal) inhibits hemagglutination (2). Mannose, GaI-Gal, and X pili may co-exist on the same bacterial strain (3, 4). Consequently, the pathogenic significance of functionally distinct pili may be difficult to assess with clinical isolates. Therefore , Hull et al. (4) cloned two distinct E. coli chromosomal fragments that encode mannose or Gat-Gal pili, into a nonpiliated K-12 derivative. The functional, serologic, and chemical properties of pili prepared from these recombinants is the subject of this report.