Part:BBa_K5175004
aldA
aldA is the gene for aldehyde dehydrogenase A, which is an enzyme with a relatively broad substrate specificity for small hydroxyaldehyde substrates and can convert glycolaldehyde (GLA) to glycolic acid (GA).
Sequence and Features
- 10INCOMPATIBLE WITH RFC[10]Illegal PstI site found at 695
Illegal PstI site found at 1408 - 12INCOMPATIBLE WITH RFC[12]Illegal PstI site found at 695
Illegal PstI site found at 1408 - 21INCOMPATIBLE WITH RFC[21]Illegal BamHI site found at 233
- 23INCOMPATIBLE WITH RFC[23]Illegal PstI site found at 695
Illegal PstI site found at 1408 - 25INCOMPATIBLE WITH RFC[25]Illegal PstI site found at 695
Illegal PstI site found at 1408
Illegal AgeI site found at 505 - 1000COMPATIBLE WITH RFC[1000]
Usage and Biology
The final products of PET degradation by the two-enzyme system are TPA and EG. However, wild-type E.coli cannot rapidly utilise these substances for various life activities.In order to increase the efficiency of E.coli in utilising the PET degradation products and to improve its viability, we overexpressed L-1,2-propanediol oxidoreductase and aldehyde dehydrogenase A.This modification was able to increase E.coli's ability to efficiently utilise EG. We chose fucO as the gene for L-1,2-propanediol oxidoreductase and aldA as the gene for aldehyde dehydrogenase A. L-1,2-propanediol oxidoreductase is an iron-dependent group III dehydrogenase, and aldehyde dehydrogenase A is an enzyme with a relatively broad substrate specificity for small hydroxyaldehyde substrates. EG is first converted in E.coli to glycolaldehyde (GLA) by L-1,2 -propylene glycol oxidoreductase, which is subsequently converted to glycolic acid (GA) by aldehyde dehydrogenase A. GA can be metabolised by condensation with acetyl coenzyme A via the glyoxalate shunt to form malic acid. GA can also enter the metabolic pathway of H. coli by condensing with succinate via isocitrate lyase (encoded by the aceA gene) , forming isocitrate.
Molecular cloning
Initially, we transformed the company-synthesized plasmids containing designed sequences into E.coli DH5α for amplification, allowing us to obtain a sufficient quantity of plasmid DNA for subsequent experiments. Following this, colony PCR was performed to confirm successful transformation, and the required plasmids were subsequently extracted for further experimentation.
Subsequently, we employed PCR to obtain the target fragments, which were then integrated into the requisite plasmids for our study.
The bands of pPeteg-P (upper band) and pPeteg-M (lower band)（~3000 bp）from PCR are identical to the theoretical lengths of 2862 bp estimated by the designed primer locations (homologous recombination fragments), which could demonstrate that these plasmids had successfully been obtained.
The bands of pEG（~3000 bp）from PCR are identical to the theoretical lengths of 2862bp estimated by the designed primer locations (promoter to terminator), which could demonstrate that these plasmids had successfully been obtained.
| None |