use strict; while () { my $data = $_; print $data if ($data !~ /(?:ATOM .{6} H )|(?:HETATM.{6} HOH)/); } __DATA__ ATOM 601 H LEU A 75 -17.070 -16.002 2.409 1.00 55.63 N ATOM 602 CA LEU A 75 -16.343 -16.746 3.444 1.00 55.50 C ATOM 603 C LEU A 75 -16.499 -18.263 3.300 1.00 55.55 C ATOM 604 H LEU A 75 -16.645 -18.789 2.195 1.00 55.50 O ATOM 605 CB LEU A 75 -16.776 -16.283 4.844 1.00 55.51 C TER 606 LEU A 75 ATOM 1185 O LEU B 75 26.292 -4.310 16.940 1.00 55.45 O ATOM 1186 CB LEU B 75 23.881 -1.551 16.797 1.00 55.32 C TER 1187 LEU B 75 HETATM 1188 HOH SRT A1076 -17.263 11.260 28.634 1.00 59.62 H HETATM 1189 HA SRT A1076 -19.347 11.519 28.341 1.00 59.42 H HETATM 1190 H3 SRT A1076 -17.157 14.303 28.677 1.00 58.00 H HETATM 1191 HOH SRT A1076 -15.110 13.610 28.816 1.00 57.77 H HETATM 1192 O1 SRT A1076 -17.028 11.281 31.131 1.00 62.63 O ATOM 295 HB2 ALA A 18 4.601 -9.393 7.275 1.00 0.00 H ATOM 296 HB3 ALA A 18 3.340 -9.147 6.043 1.00 0.00 H TER 297 ALA A 18