Table 2.

Correlation of the effect of substitution mutations on protein folding and the observed phenotypic expression in β-mannosidosis. AS: Active site

Species	Mutated residue	Structural location	Effect on structure	Effect on phenotype
Human	R182W	Away from AS	Minor perturbation	Mild
Human	G392E	Close to AS	Disrupts the ligand binding site	Moderate
Human	S505P	Close to AS (direct interaction with AS)	Disturbs the catalytic nucleophile (E457)	Severe
Human	R641H	Away from AS	Destabilizes the fold	Moderate