Structure-Based Assignment (SBA) is a technique to accelerate the resonance assignment which is a key bottleneck of NMR (Nuclear magnetic resonance) structural biology.[1] A homologous (similar) protein is used as a template to the target protein in SBA. This template protein provides prior structural information about the target protein and leads to faster resonance assignment . By analogy, in X-ray Crystallography, the molecular replacement technique allows solution of the crystallographic phase problem when a homologous structural model is
known, thereby facilitating rapid structure determination.[2] Some of the SBA algorithms
are CAP which is an RNA assignment algorithm which performs an exhaustive search over
all permutations,[3] MARS which is a program for robust automatic backbone assignment [4] and Nuclear Vector Replacement (NVR) which is a molecular replacement like approach for SBA of resonances and
sparse Nuclear Overhauser Effect (NOE)'s.[5][6][7]
^Al-Hashimi, H. M.; Gorin, A.; Majumdar, A.; Gosser, Y.; Patel, D. J. (2002), "Towards structural genomics of RNA: Rapid NMR resonance assignment and simultaneous RNA tertiary structure determination using residual dipolar couplings", J. Mol. Biol., 318 (3): 637–649, doi:10.1016/s0022-2836(02)00160-2, PMID12054812.