Study of structure-activity relationship of fasciculin by chemical modification of arginine, lysine and carboxylate groups: C. Červeñanský,1F. Dajas,1Å. Engström2 and E. Karlsson3 (1Instituto de Investigaciones Biológicas Clemente Estable, División Neuroquimica, Avenida Italia 3318, 11600 Montevideo, Uruguay; 2Department of Immunology, Biomedical Centre, Box 582, 751 23 Uppsala, Sweden; and 3Department of Biochemistry, Biomedical Centre, Box 576, 751 23 Uppsala, Sweden)