Prediction of glycolipid-binding domains from the amino acid sequence of lipid raft-associated proteins: application to HpaA, a protein involved in the adhesion of Helicobacter pylori to gastrointestinal cells.

摘要: Protein-glycolipid interactions mediate the attachment of various pathogens to host cell surface as well association numerous cellular proteins with lipid rafts. Thus, it is primary importance identify protein domains involved in glycolipid recognition. Using structure similarity searches, we could a common glycolipid-binding domain three-dimensional several known interact Yet most raft-targeted still unknown. In present study, have identified amino acid sequence bacterial adhesin (Helicobacter pylori A, HpaA). The prediction was based on major properties previously characterized by structural searches. A short (15-mer) synthetic peptide corresponding this putative synthesized, and studied its interaction monolayers at air-water interface. HpaA recognized LacCer but not Gb3. This specificity line that whole bacterium. Molecular modeling studies gave some insights into high selectivity interaction. It also suggested Phe147 played key role recognition, through sugar-aromatic CH-pi stacking hydrophobic side galactose ring LacCer. Correspondingly, replacement Ala strongly affected whereas substitution Trp did not. Our method be used microbial interacting shells, rafts, other specialized membrane microdomains.