Sequence polymorphism of the group 1 allergen of Bermuda grass pollen.
BACKGROUND
Cyn d 1, the major allergen of Bermuda grass pollen, consists of a number of isoforms.


OBJECTIVE
To examine the extent of sequence variation of Cyn d 1 isoforms at the molecular level.


METHODS
A Bermuda grass pollen lambdaZAP II cDNA expression library was immunoscreened with anti-Cyn d 1 monoclonal antibodies. The reactive clones were isolated, subcloned into Escherichia coli, and sequenced. Some of them were expressed in the yeast Pichia pastoris to obtain recombinant Cyn d 1 proteins.


RESULTS
Ten cDNA clones were obtained, all these clones encode the full length of Cyn d 1 protein. Their deduced mature proteins can be grouped into: the long ones with 246 amino acids, and the short ones with 244 amino acids. The last two amino acids (AG) of the long Cyn d 1 are deleted in the short Cyn d 1. The remaining amino acid sequences share more than 98% identity; a total of nine amino acid variations were observed. Two recombinant Cyn d 1 proteins (rCyn d 3-2 and rCyn d 5-4) with three amino acid substitutions showed differential IgE-binding profiles.


CONCLUSIONS
The present study extended our understanding of the primary structure of isoforms of Cyn d 1.
Chang
Z N
ZN
Institute of Biotechnology in Medicine, National Yang-Ming University, Taipei, Taiwan, Republic of China.
Peng
H J
HJ
Lee
W C
WC
Chen
T S
TS
Chua
K Y
KY
Tsai
L C
LC
Chi
C W
CW
Han
S H
SH
D000485:Allergens / Q000737:chemistry* / Q000235:genetics; D000595:Amino Acid Sequence; D001483:Base Sequence; D008969:Molecular Sequence Data; D008970:Molecular Weight; D006109:Poaceae / Q000276:immunology*; D011058:Pollen / Q000276:immunology*; D011110:Polymorphism, Genetic; D011994:Recombinant Proteins / Q000737:chemistry
D000485:Allergens; D011994:Recombinant Proteins