NMR study on the major mite allergen Der f 2: its refined tertiary structure, epitopes for monoclonal antibodies and characteristics shared by ML protein group members.
Group 2 major mite allergens Der f 2 and Der p 2 are classified into the recently identified group of MD-2-related lipid-recognition (ML) proteins, but the ligands and biological functions of these allergens are unknown. We have obtained a high-quality NMR structure for Der f 2, and found that it is more similar to the crystal structure of NPC2, a distant homologue, than to that of Der p 2, in terms of the separation and angle between the two major beta-sheets. This made us propose that ML proteins undergo clamshell-like motions that change the sizes of ligand-binding spaces inside their immunoglobulin-fold beta-sandwich to accommodate lipid molecules. This type of motion in lipopolysaccaride recognition of MD-2 is suggested to be likely as well by structural models. We also report the applicability of NMR differential exchange broadening experiments for complexes of intact monoclonal antibodies and antigens; using this technique, we have detected the conformational epitopes for monoclonal antibodies 15E11 and 13A4 as two separate surface patches.
Ichikawa
Saori
S
Department of Material and Biological Sciences, Faculty of Science, Japan Women's University, Mejirodai, Bunkyo-ku, Tokyo 112-8681.
Takai
Toshiro
T
Inoue
Takashi
T
Yuuki
Toshifumi
T
Okumura
Yasushi
Y
Ogura
Kenji
K
Inagaki
Fuyuhiko
F
Hatanaka
Hideki
H
D000595:Amino Acid Sequence; D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology; D000937:Antigen-Antibody Reactions; D039741:Antigens, Dermatophagoides / Q000737:chemistry* / Q000276:immunology* / Q000502:physiology; D000954:Antigens, Surface / Q000737:chemistry; D060829:Arthropod Proteins; D002352:Carrier Proteins / Q000737:chemistry; D004578:Electron Spin Resonance Spectroscopy; D000939:Epitopes / Q000276:immunology; D008070:Lipopolysaccharides / Q000378:metabolism; D051218:Lymphocyte Antigen 96; D051379:Mice; D008958:Models, Molecular; D008969:Molecular Sequence Data; D019906:Nuclear Magnetic Resonance, Biomolecular; D017434:Protein Structure, Tertiary; D016415:Sequence Alignment; D033921:Vesicular Transport Proteins / Q000737:chemistry
D000911:Antibodies, Monoclonal; D039741:Antigens, Dermatophagoides; D000954:Antigens, Surface; D060829:Arthropod Proteins; D002352:Carrier Proteins; C451160:Dermatophagoides farinae antigen f 2; C451163:Dermatophagoides pteronyssinus antigen p 2; D000939:Epitopes; D008070:Lipopolysaccharides; D051218:Lymphocyte Antigen 96; C497045:Npc2 protein, mouse; D033921:Vesicular Transport Proteins