The 1CFC and 1DMO files contain no direct distance restraints between calmodulin domain cores at residues 5–75 and 82–147

A documented inventory of the public calcium-free calmodulin entries 1CFC and 1DMO found zero deposited direct distance restraints between N-core residues 5–75 and C-core residues 82–147. A sensitivity check using residues 1–75 and 82–148 also found zero. The entries contain 1,799 and 2,500 distance restraints, respectively; 62 and 78 involve a linker residue. Across the deposited coordinate models, the unaligned C-alpha core-centroid separations range from 30.083566 to 38.539668 Å for 1CFC (25 models) and from 26.604411 to 38.485068 Å for 1DMO (30 models). These are properties of the deposited models, not physical bounds or population estimates. Linker restraints and peptide geometry may still limit domain positions. The work compares original and converted restraint counts and residue connections, but does not compare all atom names or numerical limits, calculate atom-level restraint violations, or find a restraint-satisfying distance interval. It therefore does not establish independent domain motion, absence of biological contacts, or a causal difference between entries. Exact inputs are identified by source URLs and SHA-256 checksums; release identity for the restraint files remains uncertain.

calmodulin · NMR · distance restraints · NOE · domain orientation · 1CFC · 1DMO · reproducibility