Hi chimerians... I have this pdb file with some models... MODEL ATOM 1 N ARG 2 75 3.566 -4.680 2.408 1.00 27.73 N ATOM 2 CA ARG 2 75 3.319 -3.762 1.307 1.00 27.44 C ATOM 3 C ARG 2 75 4.363 -2.641 1.381 1.00 27.43 C ATOM 4 O ARG 2 75 4.900 -2.249 2.434 1.00 26.54 O ATOM 5 CB ARG 2 75 1.901 -3.115 1.361 1.00 29.76 C ATOM 6 CG ARG 2 75 0.685 -4.005 1.574 1.00 30.19 C ATOM 7 CD ARG 2 75 1.021 -5.453 1.347 1.00 32.01 C ATOM 8 NE ARG 2 75 1.567 -5.689 0.064 1.00 35.22 N ATOM 9 CZ ARG 2 75 2.123 -6.788 -0.467 1.00 37.99 C ATOM 10 NH1 ARG 2 75 2.301 -7.901 0.253 1.00 37.85 N ATOM 11 NH2 ARG 2 75 2.343 -6.799 -1.796 1.00 37.02 N TER ATOM 1 OE1 GLU 3 561 2.565 -3.602 -1.919 1.00 35.57 O TER ENDMDL MODEL ATOM 1 N ARG B 75 3.153 -4.497 2.431 1.00 25.72 N ATOM 2 CA ARG B 75 2.895 -3.593 1.311 1.00 26.52 C ATOM 3 C ARG B 75 3.980 -2.519 1.148 1.00 26.28 C ATOM 4 O ARG B 75 4.530 -2.055 2.176 1.00 26.18 O ATOM 5 CB ARG B 75 1.566 -2.890 1.541 1.00 30.04 C ATOM 6 CG ARG B 75 0.249 -3.353 1.047 1.00 33.78 C ATOM 7 CD ARG B 75 -0.666 -3.815 2.137 1.00 37.95 C ATOM 8 NE ARG B 75 -0.707 -5.248 2.257 1.00 42.21 N ATOM 9 CZ ARG B 75 -0.886 -6.067 3.286 1.00 44.76 C ATOM 10 NH1 ARG B 75 -1.060 -5.717 4.569 1.00 44.33 N ATOM 11 NH2 ARG B 75 -0.888 -7.403 3.027 1.00 45.78 N TER ATOM 1 OE1 GLU 3 561 2.565 -3.602 -1.919 1.00 35.57 O TER ENDMDL MODEL ATOM 1 N ARG H 75 2.710 -4.027 1.931 1.00 41.50 N ATOM 2 CA ARG H 75 2.475 -2.983 0.948 1.00 38.30 C ATOM 3 C ARG H 75 3.422 -1.785 1.027 1.00 39.34 C ATOM 4 O ARG H 75 3.907 -1.419 2.105 1.00 38.57 O ATOM 5 CB ARG H 75 1.022 -2.521 1.055 1.00 41.90 C ATOM 6 CG ARG H 75 0.718 -1.195 0.370 1.00 48.73 C ATOM 7 CD ARG H 75 -0.639 -0.637 0.779 1.00 50.05 C ATOM 8 NE ARG H 75 -1.742 -1.354 0.145 1.00 56.64 N ATOM 9 CZ ARG H 75 -2.422 -2.353 0.705 1.00 57.10 C ATOM 10 NH1 ARG H 75 -2.121 -2.773 1.928 0.00 56.09 N ATOM 11 NH2 ARG H 75 -3.413 -2.931 0.040 0.00 56.09 N TER ATOM 1 OE1 GLU 3 561 2.565 -3.602 -1.919 1.00 35.57 O TER ENDMDL MODEL ATOM 1 N ARG K 75 2.718 -3.987 1.949 1.00 40.34 N ATOM 2 CA ARG K 75 2.510 -2.935 0.974 1.00 40.91 C ATOM 3 C ARG K 75 3.439 -1.730 1.052 1.00 41.44 C ATOM 4 O ARG K 75 3.779 -1.257 2.143 1.00 44.22 O ATOM 5 CB ARG K 75 1.045 -2.492 0.991 1.00 46.88 C ATOM 6 CG ARG K 75 0.759 -1.285 0.109 1.00 57.01 C ATOM 7 CD ARG K 75 -0.722 -0.981 -0.005 1.00 64.03 C ATOM 8 NE ARG K 75 -0.939 0.301 -0.673 1.00 70.73 N ATOM 9 CZ ARG K 75 -0.576 1.482 -0.173 1.00 75.39 C ATOM 10 NH1 ARG K 75 0.025 1.563 1.009 1.00 75.51 N ATOM 11 NH2 ARG K 75 -0.798 2.594 -0.862 1.00 77.70 N TER ATOM 1 OE1 GLU 3 561 2.565 -3.602 -1.919 1.00 35.57 O TER ENDMDL How can i select the 1 OE1 GLU atom in each the model? Any hint... Thanks... ;) -- Yasser Almeida Hernández, BSc Center of Molecular Inmunology (CIM) Nanobiology Group P.O.Box 16040, Havana, Cuba Phone: (537) 214-3178 almeida@cim.sld.cu ---------------------------------------------------------------- Correo FENHI