In a medium bowl combine egg, mayonnaise or salad dressing, bread crumbs, peppers, and parsley. Add crabmeat and shrimp; mix well. Form into eight 1-inch-thick patties. Place flour in a shallow dish. Coat both sides of seafood cakes with flour.
In a large nonstick skillet beat oil over medium beat. Add seafood cakes, half at a time, and cook about 6 minutes or until golden brown, turning once. Drain on paper towels. (Keep first batch warm in a 300° oven while frying remaining cakes.) Serve with the Lemon Sauce.
Lemon Sauce: In a small bowl combine 1/4 cup light mayonnaise dressing or salad dressing, 2 tablespoons light dairy sour cream, 1 tbsp snipped fresh Italian flat-leaf parsley, 1 teaspoon finely shredded lemon peel, and 1 teaspoon lemon juice.