Important salts include disodium pyrophosphate and tetrasodium pyrophosphate. Thickeners include sodium alginate, carrageenan, gelatine, sodium bicarbonate, tetrasodium pyrophosphate, and alginic acid. Pyruvate decarboxylase depends on cofactors thiamine pyrophosphate (TPP) and magnesium. Crystals include monosodium urate, calcium pyrophosphate, hydroxyapatite and corticosteroid crystals. Calcium lactate is an ingredient in some baking powders containing sodium acid pyrophosphate. The conversion requires the coenzyme thiamine pyrophosphate. E1 has two catalytic sites, each providing thiamine pyrophosphate (TPP) and magnesium ion as cofactors. E () uses thiamine pyrophosphate (TPP) as a catalytic cofactor. The thiamine pyrophosphate (TPP) converts to an ylide by deprotonation. Both synthesize histidine from the biochemical intermediate phosphoribosyl pyrophosphate. Both purine and pyrimidine synthesis use phosphoribosyl pyrophosphate (PRPP) as a starting molecule. The energy required for this linkage comes from the hydrolysis of a pyrophosphate molecule. It is classified as a pyrophosphate analog DNA polymerase inhibitor. Plants biosynthesize myrcene via geranyl pyrophosphate (GPP). Synthesis begins with mevalonic acid, which is converted into dimethylallyl pyrophosphate.