Overcrossing spectra

Figure 4 Comparison of backbones and overcrossing spectra for ribonuclease inhibitor (IBNH) and yeast hexokinase B (2YHX). These two proteins are similar in number of amino acid residues but radically different in their folding patterns. The difference is well reflected by the shape descriptor A, . The spectra are the superposition of five randomizations of projections. See Table 1.

Their different folding features become more evident upon comparison of the two overcrossing spectra (i.e., the histograms of An( ) ) in the lower part of Figure 4. [These spectra superimpose five computations with various numbers of randomized projections.] Without resorting to visual inspection, the shape descriptor indicates immediately that these two proteins have no 3D folding homology. 

The complete overcrossing spectra are contrasted in Figure 4 and 5. The statistical errors are estimated by computing five spectra for each backbone, with m = s x 10 randomized points, with s = 2, 3, 4, S, and 6. Each randomization was initialized with a different seed. See Ref. 94. 

G. A, Arteca, Biopolymers, 33, 1829 (1993). Overcrossing Spectra of Protein Backbones Characterization of Three-Dimensional Molecular Shapes and Global Structural Features. 

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