Gas vesicle protein expression for reconstitution of synthetic gas
vesicles in yeast
Abstract
Given the potential applications of gas vesicles (GVs) in multiple
fields including antigen-displaying and imaging, heterologous
reconstitution of synthetic GVs is an attractive and interesting study
that has translational potential. Here, we attempted to express and
assemble GV proteins (GVPs) into GVs using the model eukaryotic organism
Saccharomyces cerevisiae. We first selected and expressed two core
structural proteins, GvpA and GvpC from cyanobacteria Anabaena
flos-aquae and Planktothrix rubescens, respectively. We then optimized
the protein expression conditions and validated GV assembly in the
context of cell flotation and GV shapes. We found that when two copies
of AnaA were integrated into the genome, it resulted in cell floatation
and GV production regardless of GvpC expression. Next, we co-expressed
chaperone-RFP with the GFP-AnaA to aid the AnaA aggregation. The
co-expression of individual chaperones (Hsp42, Sis1, Hsp104, and GvpN)
with AnaA led to the formation of larger inclusions and enhanced the
sequestration of AnaA into the perivacuolar site. To our knowledge, this
represents the first study on reconstitution of GVs in S. cerevisiae.
Our results could provide insights into optimizing conditions for
heterologous protein expressions as well as the reconstitution of other
synthetic microcompartments in yeast.