Glucose 6 Phosphate & Mannose 6 Phosphate show only a very minor difference : the relative positions of the H and the OH on carbon 2.
This underlines the exquisite sensitivity of the
Mannose 6 Phosphate Receptor,
able to distinguish one from the other.
The mannose phosphorylation enzyme can be deficient. Many lysosomal enzymes in this case do not reach the Golgi network, or the lysosome. This happens in Mucolipidosis II or I cell disease (Inclusion cell disease), and in Mucolipidosis III (Pseudo-Hurler)
