2. Melt margarine in small saucepan over medium heat. Stir in graham cracker crumbs. Press crumb mixture firmly onto bottom and 1 inch up side of 9-inch springform pan. Bake 10 minutes. Remove from oven. Cool 10 minutes. Arrange blueberries in a single layer on top of crust. Refrigerate until needed.
3. Place 1/2 cup cold water in small saucepan; sprinkle gelatin over water. Let stand 3 minutes to soften. Heat gelatin mixture over low heat until completely dissolved, stirring constantly.
4. Combine cheeses in large bowl with electric mixer. Beat at medium speed until well blended. Beat in 1/2 cup sugar until well blended. Beat in sour cream, lemon juice and lemon peel until well blended. Beat in gelatin mixture until well blended.
5. With clean, dry beaters, beat egg whites in medium bowl with electric mixer at medium speed until soft peaks form. Gradually add remaining 1/4 cup sugar. Beat at high speed until stiff peaks form. Fold egg whites into cream cheese mixture. Gently spoon mixture into prepared crust. Cover with plastic wrap. Refrigerate 6 hours or until firm. Cut into 16 slices before serving.