Constraints Aware Plasticity Ceiling Mapping of the MERS-CoV Spike Glycoprotein: DPP4 Interface Remodeling, Cleavage Site Optimization, and Immune Escape Signatures

This dataset characterizes evolutionary boundaries of the Middle East respiratory syndrome coronavirus (MERS-CoV) spike glycoprotein through domain-resolved constraint analysis and boundary-state enumeration across three functional regions: (1) the receptor-binding domain interface with host receptor DPP4, where codon permissiveness scores identify contact residues with elevated evolutionary plasticity permitting human-adaptive substitutions; (2) the S1/S2 proteolytic cleavage motif, where boundary analysis reveals theoretical capacity for furin optimization toward polybasic configurations; (3) non-contact surface residues supporting antigenic variation without compromising receptor engagement. Domain architecture mapping confirms lethal constraints in the structural core and fusion machinery, which remain invariant across all boundary instantiations. The dataset includes nucleotide and protein FASTA files for three boundary states (receptor affinity enhancement, immune escape, cleavage optimization), codon permissiveness annotations derived from 1,746 global isolates, and domain-resolved constraint maps. Complete residue-level boundary specifications are provided in the restricted file impacted_residues.txt accompanying this deposition. These resources enable genomic surveillance pipelines to detect natural isolates approaching theoretically permissible fitness boundaries at receptor engagement and proteolytic activation sites.