The major steps in the Sulfo-TK pathway are:
* isomerization of sulfoquinovose to sulfofructose (catalyzed by sulfoquinovose isomerase);
* transketol reaction of sulfofructose to release erythrose (catalyzed by sulfofructose transketolase, a thiamine diphosphate dependent enzyme), and transfer of the C2-moiety to glyceraldehyde phosphate, yielding xylulose-5-phosphate (Xu5P). 
* 4-Sulfoerythrose is isomerized to 4-sulfoerythrulose (SEu), whereupon a second round of transketolase catalyzed reaction cleaves SE to sulfoacetaldehyde, while the C2-moiety is again transferred to an acceptor molecule, glyceraldehyde phosphate (GAP), yielding a second molecule of xylulose-5-phosphate (Xu5P). 
* Finally, the sulfoacetaldehyde is reduced to isethionate and excreted. 
The sulfoacetaldehyde may be oxidized to sulfoacetate.