The pili of Pseudomonas aeruginosa strains PAK and PAO bind specifically to the carbohydrate sequence beta GalNAc(1-4)beta Gal found in glycosphingolipids asialo-GM1 and asialo-GM2.
Pseudomonas aeruginosa employs pili to mediate adherence to epithelial cell surfaces. The pilus adhesin of P. aeruginosa strains PAK and PAO has been shown to bind to the glycolipid asialo-GM1 (Lee et al., 1994--accompanying article). PAK and PAO pili were examined for their abilities to bind to the synthetic beta GalNAc(1-4)beta Gal (a minimal structural carbohydrate receptor sequence of asialo-GM1 and asialo-GM2 proposed by Krivan et al., 1988a) using solid-phase binding assays. Both pili specifically bound to beta GalNAc(1-4)beta Gal. The binding of beta GalNAc(1-4)beta Gal-Biotin to the immobilized PAK and PAO pili was inhibited by corresponding free pili. The receptor binding domain of the PAK pilus resides in the C-terminal disulphide-looped region (residues 128-144) of the pilin structural subunit (Irvin et al., 1989). Biotinylated synthetic peptides corresponding the C-terminal residues 128-144 of P. aeruginosa PAK and PAO pilin molecules were shown to bind to the beta GalNAc(1-4)beta Gal-(bovine serum albumin (BSA)). The binding of biotinylated peptides to beta GalNAc(1-4)beta GAL-BSA was inhibited by PAK pili, Ac-KCTSDQDEQFIPKGCSK-OH (AcPAK(128-144)ox-OH) and Ac-ACKSTQDPMFTPKGCDN-OH (AcPAO(128-144)ox-OH) peptides. (In these peptides Ac denotes N alpha-acetylation of the N-terminus, -OH means a peptide with a free alpha-carboxyl group at the C-terminus and the 'ox' denotes the oxidation of the sulphhydryl groups of Cys-129 and Cys-142.) Both acetylated peptides were also able to inhibit the binding of beta GalNAc(1-4)beta Gal-biotin to the corresponding BSA-Peptide(128-144)ox-OH conjugates.(ABSTRACT TRUNCATED AT 250 WORDS)
Sheth
H B
HB
Synthetic Peptides Inc., University of Alberta, Edmonton, Canada.
Lee
K K
KK
Wong
W Y
WY
Srivastava
G
G
Hindsgaul
O
O
Hodges
R S
RS
Paranchych
W
W
Irvin
R T
RT
D018829:Adhesins, Bacterial; D000595:Amino Acid Sequence; D001422:Bacterial Adhesion; D001425:Bacterial Outer Membrane Proteins / Q000378:metabolism*; D001426:Bacterial Proteins / Q000378:metabolism*; D001667:Binding, Competitive; D002236:Carbohydrate Conformation; D002240:Carbohydrate Sequence; D036781:Fimbriae Proteins; D010861:Fimbriae, Bacterial / Q000378:metabolism*; D005677:G(M1) Ganglioside / Q000378:metabolism*; D005732:Gangliosides; D006028:Glycosphingolipids / Q000378:metabolism*; D037102:Lectins; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000138:chemical synthesis / Q000378:metabolism; D011550:Pseudomonas aeruginosa / Q000378:metabolism* / Q000648:ultrastructure; D011956:Receptors, Cell Surface / Q000378:metabolism
D018829:Adhesins, Bacterial; D001425:Bacterial Outer Membrane Proteins; D001426:Bacterial Proteins; D005732:Gangliosides; D006028:Glycosphingolipids; D037102:Lectins; D010446:Peptide Fragments; D011956:Receptors, Cell Surface; C038692:adhesin, Pseudomonas; D036781:Fimbriae Proteins; C038244:ganglio-N-triaosylceramide; D005677:G(M1) Ganglioside; C018835:asialo GM1 ganglioside