>The simplest explanation would be that those particular atoms are not in any >TLS group, and therefore they have only an isotropic ADP component. Unfortunately, the '0 0 0' for the anisotropic component in ANISOU record is for all of my protein atoms. >If that is not the case, please show the contents of the header records that >describe these 2 TLS groups. The header records are: REMARK 3 REMARK 3 TLS DETAILS REMARK 3 NUMBER OF TLS GROUPS : 2 REMARK 3 ATOM RECORD CONTAINS SUM OF TLS AND RESIDUAL B FACTORS REMARK 3 ANISOU RECORD CONTAINS SUM OF TLS AND RESIDUAL U FACTORS REMARK 3 REMARK 3 TLS GROUP : 1 REMARK 3 NUMBER OF COMPONENTS GROUP : 1 REMARK 3 COMPONENTS C SSSEQI TO C SSSEQI REMARK 3 RESIDUE RANGE : A 4 A 372 REMARK 3 ORIGIN FOR THE GROUP (A): 5.8065 -0.6242 -14.8498 REMARK 3 T TENSOR REMARK 3 T11: 0.0568 T22: 0.0595 REMARK 3 T33: 0.0153 T12: -0.0103 REMARK 3 T13: 0.0065 T23: 0.0022 REMARK 3 L TENSOR REMARK 3 L11: 1.1685 L22: 1.8292 REMARK 3 L33: 0.8417 L12: 0.0945 REMARK 3 L13: 0.2145 L23: 0.5509 REMARK 3 S TENSOR REMARK 3 S11: 0.0110 S12: -0.1328 S13: -0.1118 REMARK 3 S21: 0.2334 S22: 0.0025 S23: -0.0249 REMARK 3 S31: 0.1311 S32: 0.0150 S33: -0.0134 REMARK 3 REMARK 3 TLS GROUP : 2 REMARK 3 NUMBER OF COMPONENTS GROUP : 1 REMARK 3 COMPONENTS C SSSEQI TO C SSSEQI REMARK 3 RESIDUE RANGE : A 373 A 469 REMARK 3 ORIGIN FOR THE GROUP (A): 1.9633 16.6927 8.0263 REMARK 3 T TENSOR REMARK 3 T11: 0.0322 T22: 0.0531 REMARK 3 T33: 0.0250 T12: -0.0032 REMARK 3 T13: 0.0021 T23: -0.0070 REMARK 3 L TENSOR REMARK 3 L11: 1.7358 L22: 0.5530 REMARK 3 L33: 2.3849 L12: 0.2397 REMARK 3 L13: -0.5610 L23: -0.8025 REMARK 3 S TENSOR REMARK 3 S11: 0.0490 S12: -0.0959 S13: -0.0548 REMARK 3 S21: 0.0573 S22: -0.0352 S23: -0.0473 REMARK 3 S31: -0.0729 S32: 0.1153 S33: -0.0139 REMARK 3 Thanks Regards Shiva