Dysautonomia in Autism Spectrum Disorder: Case Reports of a Family with Review of the Literature

Figure 1

Transketolase requires TPP and magnesium as cofactors. Although the enzyme occurs twice in the hexose-monophosphate shunt, the laboratory test is for the one shown as the TPPE effect. Transketolase TK, pyruvate dehydrogenase (PDH), alpha-ketoglutarate dehydrogenase (α-KGDH) Enzymes that all require thiamine (vitamin B1/TTFD) as a cofactor in order to function in carbohydrate metabolism. glyceraldehyde 3-phosphate and fructose-6-phosphate. There are four known natural thiamine phosphate derivatives: thiamine monophosphate (TMP), thiamine diphosphate (TDP) or thiamine pyrophosphate (TPP), thiamine triphosphate (TTP), and the recently discovered adenosine thiamine triphosphate (AThTP). Thiamine pyrophosphate (TPP), also known as thiamine diphosphate (TDP), and cocarboxylase is a coenzyme for several enzymes that catalyze the dehydrogenation (decarboxylation and subsequent conjugation to Coenzyme A) of alpha-keto acids. Thiamine pyrophosphate effect really reflects the saturation status of transketolase with coenzyme.