Terpenoid metabolism

Terpenoids are produced from the 5-carbon isoprene units, isopentenyl diphosphate and dimethylallyl diphosphate. The pathway which produces the 5-carbon isoprene units is absent is Cryptosporidium species and need to be acquired from host. Terpenoids are used as precursors for production of sterols and steroids in animals. Some proteins have terpenoid moieties attached to them in order to enhance their attachment to membranes. This pathway produces polyprenyl pyrophosphate, undecaprenyl pyrophosphate and prenylated proteins such as S-geranylgeranyl protein as the end products of the pathway. This pathway is identical to the pathways of Plasmodium falciparum and Toxoplasma gondii.

 

Enzyme EC Number Gene id
Methyltransferase, MiaB 2.1.1.- cgd6_1520
Farnesylpyrophosphate synthase (Dimethylallyl-PP transferase/Geranyl transferase) 2.5.1.1; 2.5.1.10 cgd4_2550
Protein farnesyltransferase 2.5.1.29; 2.5.1.58 cgd1_1980
trans-pentaprenyltranstransferase/trans-hexaprenyltranstransferase/trans-octaprenyltranstransferase 2.5.1.30; 2.5.1.82; 2.5.1.84 cgd7_3730
di-trans,poly-cis-decaprenylcistransferase 2.5.1.31 cgd4_1510
Protein geranylgeranyltransferase type I 2.5.1.59 cgd6_1750
Protein geranylgeranyltransferase type II 2.5.1.60 cgd7_5300
tRNA isopentenyltransferase 2.5.1.75 cgd6_2540
Inorganic diphosphatase 3.6.1.1 cgd4_1400

 

Open in a new window

 

 

Sources and fates of metabolites

 

Substrate Source pathways Product Fate pathways
S-adenosylmethionine Methionine metabolism S-adenosylhomocysteine Methionine metabolism
Dimethylallyl-PP Host Farnesyl-PP N-glycan biosynthesis
Isopentenyl-PP Host