Skip to main content
Log in

Semi-rational design of L-amino acid deaminase for production of pyruvate and d-alanine by Escherichia coli whole-cell biocatalyst

  • Original Article
  • Published:
Amino Acids Aims and scope Submit manuscript

Abstract

In our previous study, one-step pyruvate and d-alanine production from d,l-alanine by a whole-cell biocatalyst Escherichia coli expressing l-amino acid deaminase (Pm1) derived from Proteus mirabilis was investigated. However, due to the low catalytic efficiency of Pm1, the pyruvate titer was relatively low. Here, semi-rational design based on site-directed saturation mutagenesis was carried out to improve the catalytic efficiency of Pm1. A novel high-throughput screening (HTS) method for pyruvate based on 2,4-dinitrophenylhydrazine indicator was then established. The catalytic efficiency (kcat/Km) of the mutant V437I screened out by this method was 1.88 times higher than wild type. Next, to improve the growth of the engineered strain BLK07, the genes encoding for Xpk and Fbp were integrated into its genome to construct non-oxidative glycolysis (NOG) pathway. Finally, the CRISPR/Cas9 system was used to integrate the N6-pm1-V437I gene into the genome of BLK07. Pyruvic acid titer of the plasmid-free strain reached 42.20 g/L with an l-alanine conversion rate of 77.62% and a d-alanine resolution of 82.4%. This work would accelerate the industrial production of pyruvate and d-alanine by biocatalysis, and the HTS method established here could be used to screen other Pm1 mutants with high pyruvate titers.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6

Similar content being viewed by others

References

Download references

Acknowledgements

This work was financially supported by the Key Research and Development Program of China (2018YFA0900504), the National Natural Science Foundation of China (31870069, 32021005) and the Fundamental Research Funds for the Central Universities (USRP52019A, JUSRP121010, JUSRP221013).

Author information

Authors and Affiliations

Authors

Contributions

KL performed the experiments, analyzed the data, and wrote the manuscript. HY and GS polished the manuscript. XL and LL conceived the project and revised the manuscript. YL, JL and GD were responsible for revising and supervising.

Corresponding authors

Correspondence to Xueqin Lv or Long Liu.

Ethics declarations

Conflict of interest

The authors declare that they have no known competing financial interests.

Research involving human participants and/or animals

This article does not contain any studies with human participants or animals performed by any of the authors.

Informed consent

This article does not contain individual participants requiring informed consent.

Additional information

Handling editor: S. Stuchlík.

Publisher's Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Supplementary Information

Below is the link to the electronic supplementary material.

Supplementary file1 (DOCX 1586 KB)

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Liu, K., Yu, H., Sun, G. et al. Semi-rational design of L-amino acid deaminase for production of pyruvate and d-alanine by Escherichia coli whole-cell biocatalyst. Amino Acids 53, 1361–1371 (2021). https://doi.org/10.1007/s00726-021-03067-8

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s00726-021-03067-8

Keywords

Navigation