Table 1.
Components of molecular chaperones in both prokaryotic and eukaryotic cells.
| Type of chaperone | Classification | Protein | Organism | Subcellar localization | Functions | Cooperating factors | energy consumption | reference |
|---|---|---|---|---|---|---|---|---|
| cytoplasmic | HSP40 | DnaJ | prokaryotic (Escherichia coli) | Cytosol, ER | Co-chaperone | – | [153], [154] | |
| Hsp60 | GroEL | prokaryotic (Escherichia coli) | Prokaryotic cytosol | (Holding and Folding chaperone) Promotes protein folding and preventing aggregation |
GroES, Hspl0, Cpnl0 | ATP (+) | [54], [155] | |
| Hsp58 | Mammals | Mitochondria | ||||||
| Cpn60 | Plants | Chloroplasts | ||||||
| HSP70 | DnaK | prokaryotic (Escherichia coli) | Prokaryotic cytosol | (Folding chaperone) Assisting refolding, Preventing aggregation, increase lysosomal degradation of cytosolic proteins, Iron-sulfur cluster protein assembly Sigma regulation, protein translocation into ER and protein translocation into mitochondria |
DnaJ, GrpE | ATP (+) | [156], [157] | |
| SSA1-4 | prokaryotic (Saccharomyces cerevisiae) | Eukaryotic cytosol | ||||||
| SSB1, 2 | prokaryotic (Saccharomyces cerevisiae) | |||||||
| Hsc73 | Mammals | |||||||
| HscA | prokaryotic (Escherichia coli) | Prokaryotic cytosol | ||||||
| HscC | ||||||||
| KAR2 | prokaryotic (Saccharomyces cerevisiae) | ER | ||||||
| BiP/Grp78 | Mammals | |||||||
| SSC1 | prokaryotic (Saccharomyces cerevisiae) | Mitochondria | ||||||
| ctHsp70 | Plants | Chloroplasts | ||||||
| HSP90 | HtpG | prokaryotic (Escherichia coli) | Prokaryotic cytosol | (Holding chaperone) Assist to folding properly, make stable condition for proteins against heat stress, Regulation of receptors, Protein translocation, Genetic buffering and protein degradation |
HSP9, Grp94 | ATP (+) | [158], [159] | |
| HSP90A | Mammals | Cytosol | ||||||
| HSP90B | Mammals | ER | ||||||
| TRAP | Mammals | Mitochondria | ||||||
| HSP100 | Hsp104 | prokaryotic (Saccharomyces cerevisiae) | Mitochondria | spread of yeast prions and clearance of aggregates | Hsp70, DnaK, ClpP, HsIV | ATP (+) | [41], [160] | |
| ClpB, C, A, X, | prokaryotic (Escherichia coli) | Cytosol | (Disaggregated chaperones) Fold properly and Disaggregate |
|||||
| Hsp78 | prokaryotic (Saccharomyces cerevisiae) | Mitochondria | ||||||
| HsIU | Plants | Chloroplast | ||||||
| sHSP | GroES | prokaryotic (Escherichia coli) | Cytosol | (Holding chaperone) Preventing aggregation during stress, Co-chaperone, provide thermotolerance in vivo and prohibition of apoptosis |
GroEL | ATP (+) | [76], [161] | |
| GrpE | DnaJ, DnaK | |||||||
| Hsp10 | Humans | Cytosol, mitochondria, Chloroplast |
– | |||||
| Hsp27 | Humans | Cytosol, ER, Nucleus | (−) | |||||
| HspB6 | Humans | Cytosol, Nucleus | ||||||
| HspB1 | Humans | Cytosol, Nucleus | ||||||
| periplasmic | Generic | Skp (OmpH) | prokaryotic (Escherichia coli) | Outer membrane | folding and assembling of outer membrane proteins and folding-assisting |
– | (−) | [93] |
| FkpA | periplasm space | |||||||
| PPIases | SurA | prokaryotic (Escherichia coli) | Outer membrane | correct folding, assembly of outer membrane proteins, folding of many newly translocated proteins | – | (−) | [102], [124], [128] | |
| PpiD | ||||||||
| FkpA | ||||||||
| PpiA (RotA) | Humans | Nucleus | ||||||
| disulfide bond formation | DsbA | prokaryotic | periplasm space | Folding of protein into the functional structure | – | (−) | [151], [162] | |
| DsbB | Inner membrane | Cooperates with ubiquinone to generate a disulfide bond | ||||||
| DsbC | periplasm space | As a disulfide bond isomerasation and facilitate folding of the protein | ||||||
| DsbD | Inner membrane | As reductive pathway | ||||||
| DsbE | periplasm space | Facilitate folding of the protein | ||||||
| DsbG | ||||||||
| Specialized | SurA | prokaryotic (Escherichia coli) |
Outer membrane | facilitates correct folding of outer membrane proteins, | – | (−) | [99] | |
| LolA (B,C,D,E) | periplasm space, Inner membrane and Outer membrane | rapid transfer of associated lipoproteins | ATP (+) | [108] | ||||
| PapD and its family | periplasm space and Outer membrane | biogenesis of pilus | (−) | [163] | ||||
| FimC | periplasm space | interacts with each pilus subunit |
(−) | [164] | ||||