FloatingEscherichia coli by Expressing Cyanobacterial Gas Vesicle Genes

摘要

Gas vesicles are hollow, air-filled polyprotein structures that provide the buoyancy to cells. They are found in a variety of prokaryotes. In this study, we isolated a partial gas vesicle protein gene cluster containinggvpA andgvpC20ΨfromPlanktothrix rubescens, and inserted it into an expression vector and expressed it inE. coli. The gas vesicle was developed in bacterial cells, which made bacterial cells to float on medium surface. We also amplifiedgvpAandgvpC20Ψseparately and synthesized an artificial operon by fusing these two genes with the standardized gene expression controlling elements ofE. coli. The artificial operon was expressed inE. coli, forming gas vesicles and floating bacteria cells. Our findings verified that the whole set of genes and the overall structure of gas vesicle gene cluster are not necessary for developing gas vesicles in bacteria cells. Two genes,gvpAandgvpC20Ψ, of the gas vesicle gene cluster are sufficient for synthesizing an artificial operon that can develop gas vesicles in bacteria cells. Our findings provided a wide range of applications including easing the harvest of cultured microalgae and bacteria, as well as enriching and remediating aquatic pollutants by constructing gas vesicles in their cells.