Protein display options
... ball and stick
Colour each amino acid
Show residue numbers ....
Show residue names ...
Remove labels & restore default colours
Cartoon format coloured by structure
- α helices pinkish red, other helices purple/dark blue, β sheets gold
(protein) Molecular surface on
Note especially the central barrel-shaped section
through which the substrate presumably passes as it is fed into the active site.
/ hide main chain
.... Molecular surface off
. . .
Rotate molecule to look down into active site
The following amino acid residues have been identified (reference below) as contributing to the conversion of glucose polysaccharides (amylose, starch) into disacccharides (maltose). Interestingly, they all have acidic side-chains (aspartic acid and glutamic acid).
ASP 197, GLU 233 & ASP300 at active site (white spacefill)
enzyme co-factors: calcium (orange) and chloride (turquoise) ions
glucose dimer (maltose - the product of starch hydrolysis) red and grey