BLBS102-c22 BLBS102-Simpson March 21, 2012 13:41 Trim: 276mm X 219mm Printer Name: Yet to Come
418 Part 3: Meat, Poultry and Seafoods67 kDa43 kDa30 kDa21 kDa14 kDa67 kDa43 kDa30 kDa21 kDa14 kDa(^4) pI (^74) pI 7
(A) (B)
(C) (D)
Figure 22.6.Two-dimensional electrophoresis liver proteome maps of four salmonid fish (S. Martin and O. Vilhelmsson, unpublished).
Running conditions are as in Figure 22.2. (A) Brown trout (Salmo trutta), (B) Arctic charr (Salvelinus alpinus), (C) rainbow trout
(Oncorhynchus mykiss), (D) Atlantic salmon (Salmo salar).
More recently, 2DE-based methods have been developed to
distinguish various closely related species, such as the gadoids or
several flat fishes (Pineiro et al. 1998, 1999, 2001). Pi ̃ ̃neiro and
coworkers have found that Cape hake (Merluccius capensis) and
European hake (Merluccius merluccius) can be distinguished on
two-dimensional gels from other closely related species by the
presence of a particular protein spot that they identified, using
nanoelectrospray ionization MS, as nucleoside diphosphate ki-
nase (Pineiro et al. 2001). Lopez and coworkers, studying three ̃
species of European mussels: (1)Mytilus edulis,(2)Mytilus gal-
loprovincialis, and (3)Mytilus trossulus, found thatM. trossulus
could be distinguished from the other two species on foot ex-
tract two-dimensional gels by a difference in a tropomyosin spot.
They found the difference to be due to a single T to D amino
acid substitution (Lopez et al. 2002). Martinez and Jakobsen
Friis (2004) attempted to identify not only the species present,
but also their relative ratios in mixtures of several fish species
and muscle types. They concluded that such a strategy would
become viable once a suitable number of markers have been
identified, although detection of species present in very differ-
ent ratios is problematic. Ortea et al. (2009a, b) used peptide
mass fingerprinting of 2DE-separated proteins to discriminate
between closely related shrimp species.
Recently, gel-free methods have received some attention.
Mazzeo et al. (2008) found that specific protein biomarkers
detectable with MALDI-TOF MS could discriminate among
several commercially important fish species, such as those be-
longing to Gadidae and Pleuronectiformes.
Identification and Characterization
of Allergens
Food safety is a matter of increasing concern to food producers
and should be included in any consideration of product quality.
Among issues within this field that are of particular concern
to the seafood producer is that of allergenic potential. Aller-
gic reactions to seafood affect a significant part of the popula-
tion: about 0.5% of young adults are allergic to shrimp (Woods
et al. 2002). Seafood allergies are caused by an immunoglobulin
E-mediated response to particular proteins, including structural