CAZypedia needs your help!
We have many unassigned pages in need of Authors and Responsible Curators. See a page that's out-of-date and just needs a touch-up? - You are also welcome to become a CAZypedian. Here's how.
Scientists at all career stages, including students, are welcome to contribute.
Learn more about CAZypedia's misson here and in this article.
Totally new to the CAZy classification? Read this first.
Absolute configuration (D/L nomenclature)
The absolute configuration of all monosaccharides is denoted by the configuration at one particular stereocentre in that sugar, namely the stereocentre furthest from the anomeric centre (the carbonyl carbon in the open chain representation). If, in the Fischer projection, that centre has the hydroxyl group on the right, it is a D-sugar; if on the left, it is an L-sugar. By convention, the "D" and "L" symbols are written in small capitals.
The configurations of the other centres relative to this define the individual sugars, e.g. D-glucose, L-threose, etc.
<centre>Fischer projections of representative sugars - the configurational "D" or "L" stereogenic centre is denoted with an asterix.</centre>