A group of campus scientists took a leap forward in the bioengineering field by redesigning a bacterial nanocompartment that can facilitate chemical reactions and could have substantial effects on the field of agriculture.
The two-year-long research project was funded by the the U.S. Department of Energy’s Office of Science and the European Union’s PEPDIODE project, and included researchers from Michigan State University, Pennsylvania State University and Brooklyn College.
Bacterial nanocompartments, or BMCs, are sturdy shells that enclose self-assembling proteins in a selectively permeable barrier. The lead researchers modified the protein-based shell of these BMCs in order to create a pathway that enables electron transfer — or movement — in and out of the bacteria.
“It is the first time anybody has taken one of the proteins that makes up the shell … to make it catalytic, or able to transfer electrons in and out of it,” said Cheryl Kerfeld, a lead scientist in this study and an adjunct associate professor in the campus department of plant and microbial biology.
The process of re-engineering the shell proteins was difficult because the BMCs encase a variety of enzymes that carry out complicated chemistry inside the bacteria.
“Once people started looking at these BMCs, they realized that there’s a good opportunity for re-engineering because they have a viral shell structure — that is actually made out of proteins and not lipids — and have enzymes that end up inside of (them),” said Arash Komeili, a campus associate professor of plant and microbial biology.
The researchers modified the shell proteins to work as a scaffold for an iron-sulfur cluster, which serves as a “cofactor,” or helper molecule, in biochemical reactions with electron transfer. To design this cluster, researchers at the Lawrence Berkeley National Laboratory had to determine the 3-D structure of the protein and how it would bind to the engineered protein using advanced X-rays.
Designing this iron-sulfur cluster was like “taking the wall of a house and making it so that it can do something that it’s not normally able to do,” Kerfeld said.
Clement Aussignargues, another lead scientist on the project from Michigan State University, said this particular study “opens possibilities for other types of mutations,” which could potentially help install other forms of nanocompartments in bacteria to produce different types of molecules.
“In the future we can probably work with the industry to coordinate what kind of chemical reactions they need,” Aussignargues said.
On a larger scale, this study could also pave the way to creating certain products, such as fertilizers, without using petroleum and other environmentally harmful elements.
“Nanocompartments can be used to help build microbial cell factories—special bacteria—that could replace nasty, toxic processes currently made by chemical companies at a high expense of energy,” Kerfeld said in an email.
Staff writer Kimberly Nielsen contributed to this report.
Contact Sofia Gonzalez-Platas at [email protected] and follow her on Twitter at agriculture, arash komeili, bacteria, Berkeley Lab, Brooklyn College, cheryl kerfeld, clement aussignargues, electrons, enzymes, Michigan State University, Pennsylvania State University