Figure 4
From: Probabilistic grammatical model for helix‐helix contact site classification
An average parse tree of accessibility‐based grammar of class 1 (Eq.26). Lengths of branches express expected level of accessibility. Terminal symbols on the tree branches represent residues of two helix pairs (panels A,B) from chain A of cytochrome b6f from C.reinhardtii (PDB code: 1Q90). The residues expected to be the most accessible, according to the grammar, are shown in blue in the parse tree and as blue balls in the structural model of the helix‐helix contact site. The acceptance rate of PDBTM helix pairs assignment to a given WDG contact site class in function of the RMSD cutoff.