| Literature References | 1. ROGERS, B.L., MORGENSTERN, J.P., GRIFFITH, I.J., YU, X.B., COUNSELL, C.M.,
BRAUER, A.W., KING, T.P., GARMAN, R.D. AND KUO, M.C.
Complete sequence of the allergen Amb alpha II. recombinant expression
and reactivity with t cells from ragweed allergic patients.
J.IMMUNOL. 147 2547-2552 (1991).
2. ROGERS, H.J., HARVEY, A. AND LONSDALE, D.M.
Isolation and characterization of a tobacco gene with homology to pectate
lyase which is specifically expressed during microsporogenesis.
PLANT MOL.BIOL. 20 493-502 (1992).
3. HIJIKATA, A., MATSUMOTO, I., KOJIMA, K. AND OGAWA, H.
Antigenicity of the oligosaccharide moiety of the Japanese cedar
INT.ARCH.ALLERGY IMMUNOL. 105 198-202 (1994).
4. WING, R.A., YAMAGUCHI, J., LARABELL, S.K., URSIN, V.M. AND MCCORMICK, S.
Molecular and genetic characterization of two pollen-expressed genes that
have sequence similarity to pectate lyases of the plant pathogen Erwinia.
PLANT MOL.BIOL. 14 17-28 (1990).
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| Documentation | Two of the major allergens in the pollen of short ragweed (Ambrosia
artemisiifolia) are Amb aI and Amb aII. The primary structure of Amb aII
has been deduced and has been shown to share ~65% sequence identity with
the Amb alpha I multigene family of allergens [1]. Members of the Amb aI/aII
family include tobacco pectate lyase, which is similar to the deduced amino
acid sequences of two pollen-specific pectate lyase genes identified in
tomato [2]; Cry jI, a major allergenic glycoprotein of Cryptomeria japonica
(Japanese cedar) - the most common pollen allergen in Japan [3]; and P56
and P59, which share sequence similarity with pectate lyases of plant
pathogenic bacteria [4].
Pectate lyase is responsible for the eliminative cleavage of pectate,
yielding oligosaccharides with 4-deoxy-alpha-D-mann-4-enuronosyl groups
at their non-reducing ends. The protein is maximally expressed late in
pollen development. It has been suggested that the pollen expression of
pectate lyase genes might relate to a requirement for pectin degradation
during pollen tube growth [4].
AMBALLERGEN is an 8-element fingerprint that provides a signature for
the pollen allergen AMB family. The fingerprint was derived from an initial
alignment of 9 sequences: the motifs were drawn from short conserved
regions spanning virtually the full alignment length - motif 5 includes
a putative active site arginine residue. Two iterations on OWL29.6 were
required to reach convergence, at which point a true set comprising 22
sequences was identified. Several partial matches were also found, all of
which are fragments and related pectate lyase sequences that match motifs
4 and 5 (many of these are from the Erwinia/bacterial pectate lyase family).
An update on SPTR37_9f identified a true set of 21 sequences, and 21
partial matches.
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