| Item | Evidence summary | Source (with citation id) | Publication (author year) | URL if present |
|---|---|---|---|---|
| Verified identity | In *Pseudomonas putida* KT2440, Pgk is explicitly annotated as phosphoglycerate kinase with locus tag PP_4963, matching the target gene/protein identity (UniProt Q88D64; gene **pgk**). It is shown in the central carbon pathway map as Pgk (PP_4963). | Pathway figure and text annotation (pqac-00000003, pqac-00000005) | Poblete-Castro et al. 2017 | https://doi.org/10.1002/9783527807796.ch8 |
| Enzymatic reaction and pathway role | PGK (EC 2.7.2.3) catalyzes the reversible reaction **1,3-bisphosphoglycerate + ADP ⇌ 3-phosphoglycerate + ATP**. In glycolysis it performs substrate-level phosphorylation to generate ATP; in gluconeogenesis it runs in reverse to form 1,3-bisphosphoglycerate. | Mechanistic/structural reviews and bacterial metabolism reference (pqac-00000006, pqac-00000011) | Serimbetov 2018; Rojas-Pirela et al. 2020 | https://doi.org/10.1098/rsob.200302 |
| Structural/mechanistic features | PGK is typically a ~45 kDa monomer with two Rossmann-like α/β domains separated by a cleft; the N-domain binds 3PG/1,3-BPG and the C-domain binds ADP/ATP. Catalysis requires hinge-bending domain closure that brings substrates from ~16 Å to ~4 Å proximity. Mg2+ is required to coordinate nucleotide phosphates and stabilize the charged transition state during direct phosphoryl transfer. | Structural analyses (pqac-00000007, pqac-00000009, pqac-00000010) | Rojas-Pirela et al. 2020; Serimbetov 2018 | https://doi.org/10.1098/rsob.200302 |
| Organism-specific pathway context | Although Pgk is present, *P. putida* KT2440 lacks 6-phosphofructokinase, so the Embden-Meyerhof-Parnas (EMP) pathway is incomplete/nonfunctional in the glycolytic direction. KT2440 relies heavily on peripheral oxidative glucose metabolism and the Entner-Doudoroff pathway; Pgk therefore operates as part of lower glycolysis/gluconeogenesis rather than a full classical EMP glycolysis. | KT2440 pathway map and regulatory review excerpts (pqac-00000000, pqac-00000003, pqac-00000016) | Poblete-Castro et al. 2017; Chen et al. 2024 | https://doi.org/10.1002/9783527807796.ch8; https://doi.org/10.1111/1751-7915.70059 |
| Pgk expression data | In transcriptome profiling of engineered *P. putida* strains for PHA production, **Pgk (PP4963)** showed minimal change: fold change **1.0** in Δgcd and **1.1** in Δgcd-pgl versus wild type, consistent with the authors’ conclusion that central metabolic pathway genes were “rather unaffected.” | Table 3 transcript data (pqac-00000001, pqac-00000002) | Poblete-Castro et al. 2013 | https://doi.org/10.1016/j.ymben.2012.10.004 |
| Quantitative physiology: glucose oxidation bias | In KT2440, most periplasmic glucose is oxidized to gluconate (**~90%**) and a smaller fraction to 2-ketogluconate (**~11%**), underscoring the dominance of peripheral oxidation over classical glycolysis. | Regulatory/pathway analysis excerpt (pqac-00000016) | Chen et al. 2024 | https://doi.org/10.1111/1751-7915.70059 |
| Quantitative physiology: electrogenic bioproduction | In an anoxic bioelectrochemical system, engineered *P. putida* mutants with reduced acetate formation improved 2-ketogluconate production; the best mutant reached a **2KG yield of 0.96 mol/mol glucose** and, in one report, accumulated 2KG at roughly **twice the wild-type rate**. | Multi-omics/electrogenic studies (pqac-00000013, pqac-00000018) | Weimer et al. 2024 | https://doi.org/10.1186/s12934-024-02509-8 |
| Quantitative physiology: carbon sourcing under anoxic electrogenesis | ^13C tracing showed acetate had **single-fraction labeling (SFL) 39.4%**, indicating only part of acetate originated from glucose and a substantial fraction came from biomass/lipid turnover; this supports major remodeling around acetyl-CoA rather than Pgk-specific regulation. | ^13C-metabolic analysis (pqac-00000015, pqac-00000017) | Weimer et al. 2024 | https://doi.org/10.1186/s12934-024-02509-8 |
| Quantitative physiology: energy status | Under anoxic electrogenic conditions, KT2440 maintained an **adenylate energy charge (AEC) of 0.52 ± 0.01** despite reduced ATP, consistent with large-scale energy-conserving remodeling of central metabolism. | Multi-omics physiology excerpt (pqac-00000017) | Weimer et al. 2024 | https://doi.org/10.1186/s12934-024-02509-8 |
| Evidence gap specific to Pgk | Recent 2023–2024 *P. putida* systems studies discuss lower glycolytic ATP formation “at the level of phosphoglycerate and pyruvate kinase” and broad central carbon remodeling, but the provided excerpts do **not** report Pgk-specific proteomic abundances, fluxes, or mutant phenotypes for PP_4963. | BES flux/omics excerpts (pqac-00000004, pqac-00000013, pqac-00000018) | Pause et al. 2024; Weimer et al. 2024 | https://doi.org/10.1111/1751-7915.14375; https://doi.org/10.1186/s12934-024-02509-8 |


*Table: This table compiles the verified identity, biochemical role, mechanistic features, pathway context, and key quantitative findings relevant to Pgk (PP_4963; UniProt Q88D64) in *Pseudomonas putida* KT2440. It is useful as a compact evidence map distinguishing direct Pgk-specific evidence from broader central-metabolism context.*