Biology Reference
In-Depth Information
Table 1
Summary of the reports of 2D-immunoblot analysis of plant allergens
Food plant
Identifi ed allergen names
Authors
Year
Reference no.
Celery
Api g 1
Vallier et al.
1992
[
5
]
Hazelnuts
Cor a 9 (11S globulin)
Beyer et al.
2002
[
6
]
Sesame
Ses i 3 (7S vicilin-type globulin)
Beyer et al.
2002
[
7
]
Ses i 2 (2S globulin)
Embryonic abundant protein
Seed maturation protein
Lupin
Conglutin
γ
Magni et al.
2005
[
8
]
11S globulin basic subunits
Peanuts
Ara h 1
Boldt et al.
2005
[
9
]
Ara h 3
Ara h 3/4
Ara h 4
Gly 1
iso-Ara h 3
Peanuts
Ara h 3 (basic subunit)
Restani et al.
2005
[
10
]
Apple
Mal d 1
Herndl et al.
2007
[
11
]
Mal d 2
Mal d 3
Mal d 4
45 kDa basic protein
Soybean
Late embryogenesis abundant protein
Batista et al.
2007
[
12
]
followed by digestion with enzymes such as trypsin, and the allergens
are identifi ed by N-terminal amino acid sequencing or mass
spectrometry/mass spectrometry (MS/MS) homology search.
Immunoproteomics is simple and inexpensive method that allows
rapid identifi cation of several IgE-binding proteins at once. Since
several IgE-binding proteins might be separated from crude extract
using 2D-PAGE, minimum 5 short days would be needed to iden-
tify them in a food extract. In addition, protocols for 2D-PAGE
have almost been optimized, whereas the protocols for allergen
isolation need to be adjusted depending on the allergens. Therefore,
the number of reports of identifi cation of novel allergens and/or
allergen location on 2D-map using immunoproteomics has been
increasing recently [
5
-
24
] (Table
1
).
In this section, we outline our protocols for the identifi cation
of food allergens using immunoproteomics and discuss a few tech-
nical points in detail. Of course, our protocols can be applied to
2D-western blotting to detect the target proteins using immunized
animal antibodies [
25
,
26
], and it is important to use optimal buf-
fers for extracting allergens from food materials. The basic principle
