Part:BBa_K3776002

DavA

DavA, 5-aminovaleramide amidohydrolase, catalyzes the reaction of 5-aminovaleramide to 5-aminovalerate in the natural 5-aminovalerate pathway in Pseudomonas putida KT2440. This DavA sequence has been codon optimized for expression in Synechococcus elongatus UTEX 2973.

References

Liu, P., Zhang, H., Lv, M., Hu, M., Li, Z., Gao, C., Xu, P., & Ma, C. (2014). Enzymatic production of 5-aminovalerate from l-lysine using l-lysine monooxygenase and 5-aminovaleramide amidohydrolase. Scientific Reports, 4(1). https://doi.org/10.1038/srep05657

Sequence and Features

Assembly Compatibility:

• 10
  COMPATIBLE WITH RFC[10]
• 12
  COMPATIBLE WITH RFC[12]
• 21
  COMPATIBLE WITH RFC[21]
• 23
  COMPATIBLE WITH RFC[23]
• 25
  COMPATIBLE WITH RFC[25]
• 1000
  COMPATIBLE WITH RFC[1000]

Contribution From NJTech-China-B 2023

Group:iGEM NJTech-China-B

Author: Yao Yao

DavA

5-Aminovaleramide amidohydrolase (DavA) plays a key role in the 5-aminovalerate pathway of various microorganisms. Here we characterized the length of the davA gene, the molecular weight of DavA protein and the activity of DavA catalytic production of 5-aminovalerate for future iGEM teams.

1 Construct design

1.1 The transformation of palsmid pRSFDuet-davA into Escherichia coli BL21(DE3)

The gene of davA was incorporated into plasmid pRSFDuet to obtain the plasmid pRSFDuet-davA. By sequencing, the correct plasmid pRSFDuet-davA was then transformed to E. coli BL21(DE3) (Figure 1).

Figure 1. The transformation of palsmid pRSFDuet-davA into E. coli BL21(DE3)

1.2 The colony PCR of pRSFDuet-davA in E. coli BL21(DE3)

The colony PCR was then performed. The results of colony PCR showed the correct length of the gene fragment, which was 750 bp approximately. The results showed that the recombinant strain that containing plasmid pRSFDuet-davA was successful obtained (Figure 2).

Figure 2. Colony PCR results of recombinant strain that containing the plasmid pRSFDuet-davA

M represents the band of DNA marker; Lane 1, 2 and 3 represent the band of different colonies containing plasmid pRSFDuet-davA

2 Protein expression of DavA

The correct colony of recombinant E. coli BL21(DE3) containing pRSFDuet-davA was inoculated and cultured. We transformed the plasmid pRSFDuet without davA gene into E.coli BL21(DE3) strain and induced protein expression under the same conditions as a control experiment. SDS-PAGE results confirmed that the molecular weight of DavA protein was correct, which was consistent with the expected molecular weight of 29.2 kDa (Figure 3).

Figure3. SDS-PAGE analysis of DavA expression in E. coli BL21(DE3)

Lane M: protein molecular weight marker; lanes 1 and 2: supernatant and precipitation of E. coli BL21(DE3) containing pRSFDuet; lanes 3 and 4:supernatant and precipitation of E. coli BL21(DE3) containing PRSFDuet-davA

3 Determination of DavB activity

3.1 Determination of DavA whole-cells catalytic activity

DavA catalyzes 5-aminovaleramide into 5-aminovalerate. We tested its activity by detecting production of 5-aminovalerate with the whole-cells containing DavA enzyme. The results showed that whole-cells containing DavA enzyme can produce 5-aminovalerate, indicating that whole-cells containing DavA have active enzyme activity (Figure 4).

Figure 4 The enzymatic activity of whole-cells congtaining DavA

3.2 Detemination of crude enzyme of DavA

The correct colony of recombinant E. coli BL21(DE3) containing pRSFDuet-davA was inoculated and cultured. We tested its activity by detecting production of 5-aminovalerate with the crude enzyme of DavA. The results showed that crude enzyme of DavA can produce 5-aminovalerate, indicating that crude enzyme of DavA has active enzyme activity (Figure 5).

Figure 5. The enzymatic activity of crude enzyme of DavA