Rice University Develops Novel System for Efficient Gas Vesicle Production
Gas vesicles are large protein nanostructures produced in microbial cells, recognized for their hollow, air-filled cylindrical form. These structures, found in certain aquatic microbes, are of scientific interest for their potential in diagnostic and therapeutic applications. However, their production in laboratory cells presents challenges, which has limited their application development.
A study published in Nature Communications by a Rice University research team, led by bioengineer George Lu, details a new genetic regulatory system designed to significantly improve cell viability during gas vesicle production.
Lu stated that gas vesicles' sound-reflecting properties make them suitable as acoustic reporter systems for biomedical research and clinical applications. He noted that previous attempts to produce the 10 genes for these structures in nonnative bacterial hosts, such as Escherichia coli, caused stress and cell death. The new genetic regulatory system aims to maintain host cell health while enabling functional nanostructure production.
"Gas vesicles' sound-reflecting properties make them suitable as acoustic reporter systems for biomedical research and clinical applications." — George Lu
A Two-Stage, Dual-Inducer Approach
Cellular stress during gas vesicle production often occurs when multiple proteins are simultaneously produced and assembled. To address this, Lu's team developed a two-stage, dual-inducer system providing precise control over the timing and quantity of protein production.
Zongru Li, a postdoctoral fellow in the Lu lab, reported that initiating the expression of assembly factors prior to producing the primary shell protein prevented toxicity often seen with simultaneous production. A two- to three-hour lead time for assembly factors ensures the cellular machinery is established before the introduction of structural proteins.
"Initiating the expression of assembly factors prior to producing the primary shell protein prevented toxicity often seen with simultaneous production." — Zongru Li
This sequential production approach, where assembly factors precede structural proteins, facilitates a more organized and efficient manufacturing process, avoiding overwhelming the cellular infrastructure.
Healthier Hosts, Higher Yields
Lu noted that this shift from simultaneous to sequential production results in healthier host organisms and increased gas vesicle yields. This method offers a robust and reliable way to produce gas vesicles for clinical and research applications and is adaptable for other multicomponent protein complexes.
Funding Support
The study received support from grants provided by the Cancer Prevention and Research Institute of Texas, the National Institutes of Health, the Welch Foundation, the G. Harold and Leila Y. Mathers Foundation, the John S. Dunn Foundation, and the Open Collective Foundation.