1 Inhibition of p - aminobenzoate and folate syntheses in plants and apicomplexan parasites by the natural product

The shikimate pathway and its branches in apicomplexan parasites.

The shikimate pathway is essential for production of a plethora of aromatic compounds in plants, bacteria, and fungi. Seven enzymes of the shikimate pathway catalyze sequential conversion of erythrose 4-phosphate and phosphoenol pyruvate to chorismate. Chorismate is then used as a substrate for other pathways that culminate in production of folates, ubiquinone, napthoquinones, and the aromatic ...

The Biosynthesis of Folic Acid

The biological importance of p-aminobenzoic acid was recognized only in 1940 when Woods showed that the compound antagonized the bacteriostatic effects of sulfonamides (2). Later, p-aminobenzoic acid was found to be an essential part of the folic acid molecule (3, 4), and it now seems quite likely that the sole metabolic function of p-aminobenzoate is to serve as a precursor for the biosynthesi...

Folate synthesis in plants: The p-aminobenzoate branch is initiated by a bifunctional PabAâ•fiPabB protein that is targeted to plastids

Pterin and folate salvage. Plants and Escherichia coli lack capacity to reduce oxidized pterins.

Dihydropterins are intermediates of folate synthesis and products of folate breakdown that are readily oxidized to their aromatic forms. In trypanosomatid parasites, reduction of such oxidized pterins is crucial for pterin and folate salvage. We therefore sought evidence for this reaction in plants. Three lines of evidence indicated its absence. First, when pterin-6-aldehyde or 6-hydroxymethylp...

Folate absorption

Folic acid, or pteroylglutamic acid, is the parent substance of a large group of related compounds called 'folates'. All folate compounds have the same basic molecular structure consisting of three parts: pteridine, para-aminobenzoate (these two together forming a pteroyl group), and L-glutamic acid (Fig. 1). Pteroylglutamic acid itself is a stable, watersoluble compound with a molecular weight...