Table 3.
Residueb | Proposed role (region) |
---|---|
Residueb3 | Proposed role (region) |
R11 | General acid/base |
T7 | Domain 1-to-4 latch |
T414 | |
S100 | Phosphoserine involved in phosphoryl transfer (i) |
D240 | Metal-binding ligands (ii) |
D242 | |
D244 | |
D308c | Specific/permissive for amino group at 2 position of sugar |
M285c | |
E325 | Sugar-binding loop (iii) |
S327 | |
R410 | Phosphate-binding site (iv) |
S412 | |
R419 |
All residues in this table are 100% conserved based on a multiple sequence alignment of 171 PNGM sequences (see the supplemental material).
Residue numbers refer to the BaPNGM protein.
Proposed role of D308 is specificity for binding glucosamine-6-P, while M285 appears to be permissive for binding glucosamine-1-P. The four conserved active site regions discussed in the text are indicated in parentheses.