| Category | Summary (1-2 sentences) | Key evidence & quantitative data | Key sources (include DOI URL and year) |
|---|---|---|---|
| Protein identity/family & domains | Q88N56 in *Pseudomonas putida* KT2440 corresponds to GroES (Hsp10/Cpn10), the small co-chaperonin partner of GroEL in the conserved bacterial GroEL/GroES chaperonin system. The literature for *Pseudomonas* heat-shock/chaperonin biology is fully consistent with the UniProt annotation for locus PP_1360 as GroES adjacent to groEL/PP_1361. | In KT2440 transcriptomics, PP_1360 is explicitly annotated as “co-chaperonin GroES,” with neighboring PP_1361 annotated as “chaperonin 60 kDa” (GroEL), matching the expected GroES/GroEL pair (pqac-00000001). GroES is defined mechanistically as a heptameric ~10 kDa lid-shaped cofactor that caps GroEL rings (pqac-00000005, pqac-00000006). | Follonier et al., 2013, https://doi.org/10.1186/1475-2859-12-30 (2013) (pqac-00000001); Wagner et al., 2024, https://doi.org/10.1038/s41586-024-07843-w (2024) (pqac-00000005); Gardner et al., 2023, https://doi.org/10.1073/pnas.2308933120 (2023) (pqac-00000006) |
| Molecular function | GroES acts as the co-chaperonin “lid” for GroEL, enabling ATP-dependent encapsulation of non-native proteins in a folding chamber rather than catalyzing a chemical reaction. Its primary role is to bind GroEL and help convert the chaperonin into a protected environment that promotes productive folding and limits aggregation. | GroES binding to GroEL is ATP-dependent and creates the cis folding chamber; encapsulation buries hydrophobic surfaces and allows substrate folding before release (pqac-00000005, pqac-00000006). The GroEL/GroES cavity can accommodate many proteins up to ~60 kDa, with most *E. coli* GroEL substrates concentrated around 20-40 kDa and sharply declining above ~50 kDa (pqac-00000006, pqac-00000010). | Wagner et al., 2024, https://doi.org/10.1038/s41586-024-07843-w (2024) (pqac-00000005); Gardner et al., 2023, https://doi.org/10.1073/pnas.2308933120 (2023) (pqac-00000006); Taguchi & Koike-Takeshita, 2023, https://doi.org/10.3389/fmolb.2023.1091677 (2023) (pqac-00000010) |
| Biological process | GroES participates in bacterial proteostasis and the heat-shock/stress response by assisting GroEL-mediated folding of proteins produced during normal growth and under stress. In *P. putida*, the groE system is part of the σ32/RpoH-linked heat-shock network. | In *P. putida* KT strains, GroEL and associated heat-shock proteins are rapidly induced after temperature upshift, and σ32/RpoH governs the heat-shock response with induction peaking within ~5-15 min in proteobacteria (pqac-00000000, pqac-00000003). Under elevated-pressure stress in KT2440, groES and groEL are upregulated together with rpoH and other heat-shock genes, consistent with a proteostasis response (pqac-00000001). | Ito et al., 2014, https://doi.org/10.1002/mbo3.217 (2014) (pqac-00000000, pqac-00000003); Follonier et al., 2013, https://doi.org/10.1186/1475-2859-12-30 (2013) (pqac-00000001) |
| Cellular localization | GroES functions in the cytosol, where it transiently binds the cytosolic GroEL double-ring complex to form enclosed folding chambers for soluble protein substrates. No evidence in the provided context suggests secretion, membrane localization, or extracellular activity. | GroEL/GroES is described as a cytosolic folding machine that encloses substrate proteins in central chambers; in situ cryo-ET visualized these assemblies directly inside bacterial cells (pqac-00000005). The functional readout is folding and release of encapsulated substrate back into the cytosol (pqac-00000005, pqac-00000007). | Wagner et al., 2024, https://doi.org/10.1038/s41586-024-07843-w (2024) (pqac-00000005, pqac-00000007) |
| Operon/genomic context | In KT2440, groES is located at PP_1360 adjacent to groEL/PP_1361, strongly supporting a canonical groES-groEL locus. The retrieved evidence supports adjacency, but the precise transcript boundaries of a bicistronic operon were not directly mapped in the provided context. | The KT2440 stress-transcriptome table lists consecutive loci PP_1360 (groES) and PP_1361 (groEL), both induced under the same stress conditions (pqac-00000001). Broader *Pseudomonas* heat-shock literature treats GroEL/GroES as part of the heat-shock regulon (pqac-00000002). | Follonier et al., 2013, https://doi.org/10.1186/1475-2859-12-30 (2013) (pqac-00000001); Craig et al., 2021, https://doi.org/10.3389/fmicb.2021.660134 (2021) (pqac-00000002) |
| Regulation/induction conditions | The best organism-specific evidence indicates that groES/groEL is stress inducible in *P. putida* KT2440 and linked to the heat-shock regulatory network involving σ32/RpoH. Expression rises under elevated pressure and likely also under heat-shock-like conditions, although the supplied KT2442 data quantify groEL rather than groES directly. | Under elevated pressure in KT2440, groES/PP_1360 increased +1.61-fold (adjusted P = 2.0E-02), and under pressure + elevated dissolved oxygen it increased +1.77-fold (adjusted P = 8.2E-02); groEL/PP_1361 increased +1.78-fold (adjusted P = 1.0E-02) and +2.19-fold (adjusted P = 6.0E-03), while rpoH/PP_5108 increased +1.49-fold and +1.57-fold, respectively (pqac-00000001). In KT strains, groEL is significantly induced within 10 min after transfer to higher temperatures, even at 33°C, with sustained induction up to 30 min at 40-45°C (pqac-00000003). | Follonier et al., 2013, https://doi.org/10.1186/1475-2859-12-30 (2013) (pqac-00000001); Ito et al., 2014, https://doi.org/10.1002/mbo3.217 (2014) (pqac-00000003) |
| Phenotypes/essentiality (note if not found) | Direct *P. putida* KT2440/KT2442 groES knockout or essentiality data were not found in the provided context, so strain-specific essentiality should be treated as not directly demonstrated here. However, GroEL/GroES is broadly described as an indispensable bacterial chaperone system in many bacteria, supporting strong functional importance by conservation. | The supplied *P. putida* studies did not report a groES null mutant phenotype or direct essentiality test (pqac-00000000, pqac-00000003). More generally, GroEL/GroES is described as the only indispensable chaperone system for bacterial viability in most bacteria, based largely on model-organism evidence (pqac-00000010). | Ito et al., 2014, https://doi.org/10.1002/mbo3.217 (2014) (pqac-00000000, pqac-00000003); Taguchi & Koike-Takeshita, 2023, https://doi.org/10.3389/fmolb.2023.1091677 (2023) (pqac-00000010) |
| Recent (2023-2024) advances relevant to GroES/GroEL | Recent structural work substantially refined the current model of GroES/GroEL action and is directly relevant to functional annotation of *P. putida* groES because GroES function is highly conserved. These studies support a dynamic cycle involving asymmetric and symmetric GroEL-GroES complexes, substrate capture on the trans ring, and substrate encapsulation/release through distinct conformational states. | A 2023 cryo-EM study showed GroEL-ADP·AlF3-GroES and related states with asymmetric substrate engagement, where 4 GroEL subunits contact a 50.5 kDa Rubisco client while 3 adopt a GroES-accepting conformation; GroES binding roughly doubles chamber volume (pqac-00000006). A 2024 in situ cryo-ET study found ~55-60% asymmetric EL-ES1 and ~40-45% symmetric EL-ES2 complexes during typical growth, shifting to ~70% EL-ES1 under heat stress; GroEL/GroES abundance rose ~3-fold, the GroEL:ribosome ratio changed from ~1:23 to ~1:10, and EL-ES1 narrow vs wide trans-ring openings were ~45 Å vs ~65 Å (pqac-00000004, pqac-00000007). | Gardner et al., 2023, https://doi.org/10.1073/pnas.2308933120 (2023) (pqac-00000006); Wagner et al., 2024, https://doi.org/10.1038/s41586-024-07843-w (2024) (pqac-00000004, pqac-00000007) |
| Applications/biotech implementations | Although not specific to *P. putida* PP_1360, GroEL/ES has active biotechnology use as a folding aid for difficult recombinant proteins, which is relevant because it operationalizes the core function of GroES as a co-chaperonin. Current implementations mainly use GroEL/ES co-expression to reduce aggregation and increase soluble product yield in microbial cell factories. | Recent examples include improved soluble expression of problematic recombinant proteins by GroEL/ES co-expression, including difficult enzymes and viral proteins (pqac-00000002). More broadly, *Pseudomonas* stress-response knowledge, including chaperone systems such as GroEL/GroES, is being leveraged for industrial strain robustness and process optimization (pqac-00000002). | Craig et al., 2021, https://doi.org/10.3389/fmicb.2021.660134 (2021) (pqac-00000002) |


*Table: This table summarizes the most relevant functional annotation evidence for *Pseudomonas putida* KT2440 groES (Q88N56/PP_1360), integrating strain-specific data with recent conserved mechanistic insights on the GroES/GroEL chaperonin system. It is useful for distinguishing direct organism-specific evidence from broader, well-supported inference based on the highly conserved GroES family.*