[The role of single amino acid residues of the immunodominant continuous epitope of cytochrome P450CAM (CYP101) 312LKKGDQ317 in recognition by specific antibodies].
As it has been shown previously the site 311-318 of bacterial cytochrome P450cam (CYP101) contains an immunodominant continuous B-epitope. In order to investigate the role of single amino acid residues in antibody binding antigenic hexapeptide 312LKKGDQ317 analogues including single amino acid replacements were synthesized using Multipin technology. Antibodies from three anti-P450cam polyclonal rabbit sera interacted similarly to these peptides. The residue G315 was found to play a significant role in antibody recognition; any replacement leads there to considerable decrease of antibody binding. Residues L312, K313 and D316 occurred to be partly replaceable, whereas K314 and Q317 were not essential in recognition. These results correspond to known spatial structure of P450cam molecule. In its 312-317 site the polypeptide chain makes a turn and so some water-accessible atoms form a compact surface cluster including side chain atoms of K313 and D316, O-atom of K314 and C alpha-atom of G315, which present reliable Ig binding site. Side chain of K314 outlying from this cluster does not participate in the interaction. The received data permit to consider that the continuous epitope 312-317 of P450cam is conformationally dependent.
Moshkovskiĭ
S A
SA
Orekhovich Institute of Biomedical Chemistry RAMS, 10, Pogodinskaya Str., Moscow, 119992 Russia.
Lebedev
D N
DN
Kolesanova
E F
EF
Archakov
A I
AI
D000596:Amino Acids / Q000737:chemistry*; D000818:Animals; D000906:Antibodies / Q000737:chemistry* / Q000276:immunology; D000918:Antibody Specificity; D019475:Camphor 5-Monooxygenase / Q000737:chemistry* / Q000276:immunology; D018604:Epitope Mapping; D000939:Epitopes; D010446:Peptide Fragments / Q000737:chemistry* / Q000276:immunology; D011487:Protein Conformation; D011817:Rabbits
D000596:Amino Acids; D000906:Antibodies; D000939:Epitopes; D010446:Peptide Fragments; D019475:Camphor 5-Monooxygenase