5.2.1 Molecular Biological Properties
 

17-kDa Allergen	References
Allergen Nomenclature Cor a 1	(1) Larsen & Lowenstein 1999
Isoallergens and Variants 4 isoallergens by SDS/IEF-PAGE (1) 4 recombinant isoallergens with aa identities of 96-99% (2)	(1) Rohac et al. 1991 (2) Breiteneder et al. 1993
Molecular Mass  17 kDa (1), (SDS-PAGE)	(1) Rohac et al. 1991
Isoelectric Point pI 5.0-5.8 (1)	(1) Rohac et al. 1991
Amino Acid Sequence,mRNA, and cDNA Cor a 1 5  6  11 16 SWISS-PROT: Q08407 Q08407 Q08407 Q08407 GenBank: X70999 X71000 X70997 X70998 PIR: S30053 S30054 S30055 S30056 Amino Acids 159 aa 159 aa 159 aa 159 aa mRNA 619 bp 742 bp 655 bp 860 bp cDNA	(1) Breiteneder et al. 1993
recombinant Protein Expression in Escherichia coli: 4 recombinant isoforms (1, 2)	(1) Breiteneder et al. 1993 (2) Schenk et al. 1994
Biological Function Bet v 1 family of pathogenisis-related proteins (1)	(1) SWISS-PROT
Sequence Homology to Cor a 1 isoforms: Birch pollen allergen Bet v 1: aa 71-73% identity, 80.5-83% similarity (1) Alder pollen allergen Aln g 1: aa 75.5-76.7% identity, 83.6-85% similarity (1) Hornbeam pollen allergen Car b 1: aa 83.6-89.9% identity, 89.3-95% similarity (1) Apple allergen Mal d 1: aa 54% identity (2)	(1) Breiteneder et al. 1993 (2) Vieths et al. 1996

 5.2.2 Allergenic Properties
 

17-kDa Allergen	References
Frequency of Sensitization IgE-binding to Cor a 1 in 100% of patients (1)	(1) see 5.1 Sensitization to Hazel Allergens
Allergenic Potencies Differential IgE reactivity to 4 rCor a 1 isoforms by samples of 5 hazelpollen allergic patients (immunoblot) (1, 2)	(1) Breiteneder et al. 1993 (2) Schenk et al. 1994
Cross-reactivity IgE- cross- reactive to rBet v 1 (1)	(1) see 7 Cross-Reactivities
T-Cell Proliferation / Epitopes Stimulation of Bet v 1 specific T-cell clones with natural Cor a 1 (1) Stimulation of Bet v1 specific T-cell clones from birch pollen and hazelpollen allergic patients with natural and recombinant Cor a 1 isoforms (2): Isoform Positive Stimulation:  nCor a 1 in 4/6 clones rCor a 1/5 in 3/6 clones rCor a 1/6 in 5/6 clones rCor a 1/11 in 3/6 clones rCor a 1/16 in 4/6 clones Stimulation of Bet v1 specific T-cell clones from birch pollen and hazelpollen allergic patients with synthetic peptides according to internal sequences of rCor a 1 isoforms and rBet v 1 (2): rCor a 1 5 6 11 16 rBet v 1 aa 12-23 + + + - + aa 63-74 * (1) + + + + + aa 77-88 - + + - + aa 97-108 - +/- - +/- +/- aa 111-122 + + + + + aa 144-155 + + + + + * same sequence in all Cor a 1 isoforms Amino acids critical for T-cell proliferation with synthetic peptides (2): aa 12-23 position 14 (substitution Pro / Ser)  aa 77-88 position 80 (substitution Lys / Thr) aa 97-108 position 100 (substitution Ser / His)	(1) Ebner et al. 1993 (2) Schenk et al. 1994