Preparation of umami octopeptide with recombined Escherichia coli: Feasibility and challenges

Liming Zhao,Yin Zhang,Chandrasekar Venkitasamy,Zhongli Pan,Longyi Zhang,Siya Guo,Wei Xiong,Hu Xia,Liu Wenlong,Gou Xinhua

doi:10.1080/21655979.2017.1378839

Abstract

ABSTRACTThe taste of umami peptide H-Lys-Gly-Asp-Glu-Glu-Ser-Leu-Ala-OH (LGAGGSLA) is controversial. One possible reason for this controversy is the use of chemically synthesized LGAGGSLA to confirm its taste. To explore other ways to further confirm the flavor of LGAGGSLA, we developed a new strategy to prepare a bio-source peptide by adopting a gene engineering method to express LGAGGSLA in recombinant Escherichia coli. In our previous work, we structured the LGAGGSLA recombinant expression system and optimized the culturing conditions for preparing a fusion protein. However, the fusion protein was not cleaved by enterokinase to obtain LGAGGSLA. Because the cleavage conditions of commercial enterokinase were not specific and recombinant engineered bacteria had the potential to be used in industrial processes, in this addendum, we calculated the mass and volume yields of key processing steps in the preparation of LGAGGSLA, and established a model of cleavage conditions with the cleavage ratio of LGAGGSLA. When the LGAGGSLA was confirmed to show umami taste, it is considered as a new umami or umami enhancer. The gene information of LGAGGSLA should have a great potential in the development of new flavor product and food product containing high umami flavor.

Highlights

In our recent work, we structured the umami recombinant expression of octopeptide in Escherichia coli, H-Lys-Gly-Asp-Glu-Glu-Ser-Leu-Ala-OH (LGAGGSLA), and optimized its culturing conditions for preparing a fusion protein.[1]
We just obtained the fusion protein in our previous work, which had to be cleaved by enterokinase (EK) to obtain LGAGGSLA
Since structured engineering bacteria can be adopted to prepare LGAGGSLA in laboratories and have potential to be used in industrial processes, the mass and volume yields of key steps in the process of preparing LGAGGSLA were calculated in this addendum

Summary

Introduction

We structured the umami recombinant expression of octopeptide in Escherichia coli, H-Lys-Gly-Asp-Glu-Glu-Ser-Leu-Ala-OH (LGAGGSLA), and optimized its culturing conditions for preparing a fusion protein.[1]. We structured the umami recombinant expression of octopeptide in Escherichia coli, H-Lys-Gly-Asp-Glu-Glu-Ser-Leu-Ala-OH (LGAGGSLA), and optimized its culturing conditions for preparing a fusion protein.[1] It was reported that LGAGGSLA showed umami taste in 1978,2 but its flavor was controversial due to the inconsistency in the verification results.[3] Use of synthesized LGAGGSLA to confirm its taste might be the most likely reason for the flavor disputation.[3,4,5] Based on this speculation, we tried to prepare bio-source LGAGGSLA to further confirm its taste.

Results

Conclusion