| Aspect | Key finding | Evidence source (first author year) | Publication date | URL | Citation id(s) |
|---|---|---|---|---|---|
| identity/locus | The target in *Pseudomonas putida* KT2440 is PP1009 (PP_1009), annotated as **gap-1 / gapA-like**, encoding glyceraldehyde-3-phosphate dehydrogenase; it is reported as **monocistronic** in the PP1009–PP1024 chromosomal region. | del Castillo 2008 | Apr 2008 | https://doi.org/10.1128/jb.01726-07 | (pqac-00000005, pqac-00000006) |
| reaction | GapA/GAPDH catalyzes oxidation/phosphorylation of D-glyceraldehyde-3-phosphate with inorganic phosphate to 3-phospho-D-glyceroyl phosphate (1,3-bisphosphoglycerate), producing **NADH**; one source notes the enzyme can act slowly on other aldehydes and thiols can substitute for phosphate. | Geiger 2019 | 2019 | not available | (pqac-00000003) |
| cofactor specificity | Available evidence supports **NAD-linked** GAPDH activity through explicit NADH formation in the reaction description. No KT2440-specific experimental evidence for NADP preference was retrieved in the gathered sources, so cofactor specificity beyond NAD-linked activity remains unresolved here. | Geiger 2019 | 2019 | not available | (pqac-00000003) |
| pathway role | In KT2440 glucose catabolism, GAP is the **end product of the Entner–Doudoroff (ED) pathway** and is converted to **3-phosphoglycerate (3-PG)** by GapA or the isozyme PP_3443 in the **lower EMP pathway**. HexR-regulated glucose pathways funnel carbon to the central intermediate 6-phosphogluconate and onward to GAP/pyruvate. | Chen 2024; del Castillo 2008 | Nov 2024; Apr 2008 | https://doi.org/10.1111/1751-7915.70059 ; https://doi.org/10.1128/jb.01726-07 | (pqac-00000000, pqac-00000001, pqac-00000007) |
| regulation | **HexR represses gapA/gap-1**: in a **hexR** mutant, PP1009/gap-1 expression increased **4.89-fold** (**P = 0.01**). More recent work places gapA among catabolic genes induced by glucose and gluconate; several glucose-catabolism genes increased **almost 100-fold** under these conditions, although a gapA-specific fold-change was not given in the excerpt. | del Castillo 2008; Chen 2024 | Apr 2008; Nov 2024 | https://doi.org/10.1128/jb.01726-07 ; https://doi.org/10.1111/1751-7915.70059 | (pqac-00000005, pqac-00000006, pqac-00000000, pqac-00000001, pqac-00000009) |
| quantitative data | In the **hexR** mutant, overall physiology remained near wild type under tested conditions despite transcriptional derepression: growth rates were about **0.57 ± 0.01 to 0.60 ± 0.02 h−1**, and glucose consumption rates about **6.84 to 9.7 mmol glucose g cell biomass−1 h−1**. | del Castillo 2008 | Apr 2008 | https://doi.org/10.1128/jb.01726-07 | (pqac-00000005, pqac-00000006) |
| isozyme context | KT2440 has at least **two GAPDH isozymes, GAPA and GAPB**. Proteomics in 2024 showed **GAPA decreased twofold** (**p < 0.01**) in glucose+ferulate versus glucose alone, while **GAPB was unchanged** (**p > 0.392**). The authors interpret prior work as functional partitioning in which **GAPA supports lower glycolysis** and **GAPB supports gluconeogenesis**. | Mendonca 2024 | Jun 2024 | https://doi.org/10.1021/acs.est.4c01328 | (pqac-00000008) |
| pathway/physiology context | During glucose or gluconate feeding, gapA grouped with ED/PP/EMP catabolic genes induced by both substrates. During mixed-substrate growth with ferulate, ED pathway usage remained prominent and glycolytic flux downstream of GAP was favored despite lower GAPA abundance. | Chen 2024; Mendonca 2024 | Nov 2024; Jun 2024 | https://doi.org/10.1111/1751-7915.70059 ; https://doi.org/10.1021/acs.est.4c01328 | (pqac-00000001, pqac-00000008) |


*Table: This table compiles evidence-based findings for *Pseudomonas putida* KT2440 gapA/PP_1009, including identity, enzymatic function, regulation, pathway placement, and quantitative observations. It highlights what is directly supported by retrieved sources and where evidence remains inferential or incomplete.*