Table 6.
Summary of HSPs applied in tolerance engineering.
| HSPs | Microbes | Methods | Final results | Refs |
|---|---|---|---|---|
| groESL | Clostridium tyrobutyricum | overexpressing native groESL | Tolerance to butyric acid was markedly improved. | [93] |
| groESL | Clostridium tyrobutyricum | overexpressing native groESL | Tolerance to lignocellulosic hydrolysate-derived inhibitors was noticeably improved, in particular to phenolic compounds | [115] |
| groESL | Escherichia coli | overexpressing native groESL | Adequate expression level of GroESL is pivotal in improving phloroglucinol tolerance. | [116] |
| groESL | Escherichia coli | heterologously overexpressing native groESL from Pseudomonas putida | The thermo-tolerance and ethanol-tolerance were significantly increased. | [117] |
| groESL | Clostridium acetobutylicum | heterologously overexpressing native groESL from Thermoanaerobacter tengcongensis | Tolerance to corn cob hydrolysates was improved. | [117] |
| groESL | C. acetobutylicum ATCC824 | overexpressing native groESL | Tolerances to a variety of stresses including butanol, furfural, oxidation and acid was improved. | [98] |
| groESL | C. acetobutylicum ATCC824 | heterologously overexpressing native groESL from Deinococcus wulumuqiensis R12 | Tolerances to a number of stresses including butanol, furfural, oxidation and acid were improved. | [98] |
| groESL | Clostridium tyrobutyricum | overexpressing native groESL | Tolerance of C. tyrobutyricum to furfural was improved | [97] |
| htpG | Clostridium tyrobutyricum | overexpressing native groESL | The tolerance to butyric acid was significantly improved. | [93] |
| DnaK | C. acetobutylicum ATCC824 | heterologously overexpressing native DnaK from Deinococcus wulumuqiensis R12 | Tolerances to some stress conditions including butanol, furfural, oxidation and acid were improved. | [98] |
| DnaK | Escherichia coli | heterologously overexpressing native DnaK from Bacillus halodurans | The salt resistance and high pH (9.5) tolerance were improved. | [118] |
| DnaK | Lactococcus lactis NZ9000 | overexpressing native Dnak | The engineered strain exhibited greater heat resistance at 40 °C. | [99] |
| DnaK | Lactococcus lactis NZ9000 | heterologously overexpressing native DnaK from Escherichia coli JM109 | The engineered strain exhibited excellent tolerance to multiple stresses, such as 3 % NaCl, 5 % ethanol and 0.5 % lactic acid. | [99] |
| DnaK | Escherichia coli BL21（DE3） | heterologously overexpressing native DnaK from Bacillus pumilus strain B3 | The engineered strain was imparted tolerance to host cells under high temperature. | [119] |
| DnaK | Escherichia coli BL21 (DE3) | heterologously overexpressing native DnaK from Alicyclobacillus acidoterrestris | The resistance against heat (54–58 °C) and acid (5.07–7.0) stresses was significantly enhanced. | [120] |
| DnaK | Pseudomonas putida | mutation in dnaK | Tolerance to toluene was improved. | [100] |
| SecB | E. coli | screen HSPs library and directed evolution on secB | Tolerance to n-butanol and the growth increased by 3.2-fold compared to the control strain in 1.2 % (v/v) butanol. Mutation secBt10a could greatly grew from 9.14 to 14.4 % at 1.2 % butanol, which was 5.3 times higher than the control strain | [101] |