aroF-I (PP_2324) encodes a predicted class-I 3-deoxy-D-arabino-heptulosonate 7-phosphate synthase (DAHP synthase; EC 2.5.1.54) in Pseudomonas putida KT2440. DAHP synthase catalyzes the aldol-like condensation of phosphoenolpyruvate and D-erythrose 4-phosphate to form DAHP, the first committed step of the shikimate pathway. That pathway produces chorismate, the branch-point precursor for phenylalanine, tyrosine, tryptophan, folate, ubiquinone, and other aromatic metabolites. KT2440 has multiple DAHP synthase paralogs, including aroH, aroF-I, and aroF-II, whose feedback regulation and relative in vivo flux contributions remain unresolved.
| GO Term | Evidence | Action | Reason |
|---|---|---|---|
| GO:0003849 3-deoxy-7-phosphoheptulonate synthase activity | IEA GO_REF:0000120 | ACCEPT | Summary: aroF-I is a class-I DAHP synthase family protein with EC 2.5.1.54 annotation, matching condensation of phosphoenolpyruvate and erythrose 4-phosphate to DAHP. Reason: This is the core molecular function and is supported by PIRNR/Pfam/InterPro family evidence. Direct biochemical data for this specific paralog were not found in this first pass. |
| GO:0005737 cytoplasm | IEA GO_REF:0000118 | ACCEPT | Summary: DAHP synthase is a soluble central-metabolism enzyme acting on cytoplasmic substrates. Reason: Cytoplasmic localization is appropriate for a bacterial shikimate-pathway enzyme and no secretion or membrane features are indicated. |
| GO:0009073 aromatic amino acid biosynthetic process | IEA GO_REF:0000120 | ACCEPT | Summary: DAHP synthase initiates the shikimate pathway that supplies chorismate for all three aromatic amino acid branches. Reason: Correct biological process for this enzyme class. The specific aromatic amino-acid branch affected by this paralog's feedback regulation is not resolved. |
| GO:0042802 identical protein binding | IEA GO_REF:0000117 | MARK AS OVER ANNOTATED | Summary: Class-I DAHP synthases are commonly oligomeric, but identical protein binding is a generic structural interaction term rather than the informative biochemical function. Reason: The annotation adds little beyond the catalytic DAHP synthase activity and appears electronically propagated. Generic protein-binding-style terms are not useful as core molecular functions here. |
| GO:0009423 chorismate biosynthetic process | IEA GO_REF:0000041 | ACCEPT | Summary: DAHP synthase catalyzes the entry reaction into the shikimate pathway, upstream of chorismate. Reason: This is the most specific pathway-process annotation available in GOA for the anabolic role of aroF-I. |
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