A protein from cyanobacteria has been redesigned into a homing beacon to attract molecular payloads. The long-term goal: to organize resources inside living cells for medical or industrial applications.
'Hoarding' resources in the same location encourages more efficient chemical reactions. Someday, we could use this system to enhance the production of rubber, biofuels, and other commodities.
The genetically engineered shell is based on natural structures and the principles of protein evolution. Scientists see such structures as a source of new industrial or medical technologies.
MSU scientists report how cyanobacteria line up their CO2-fixing factories within them in a system that works like Velcro. The research is part of an effort to control and repurpose these factories to make products for human consumption.
The new methods let scientists assemble the factories on demand and insert custom molecules inside them for further processing. The aim is to eventually design sustainable medical, industrial, or energy applications.
The Kerfeld lab announces two new methods for manipulating bacterial factories for biotech aims: one is to screen and extract the factories, the other is to predictably insert custom enzymes in them.
The Kerfeld lab has analyzed over 200 sets of cyanobacteria DNA. This knowledge is getting us closer to understanding how to build synthetic factories that will someday produce green fuels or products used to diagnose diseases.
The new compartment, widely spread among different kinds of bacteria, might be reassembled to someday sustainably produce “green” chemicals, medicines, and renewable energy.
[VIDEO] Our first ever look at bacterial organelle shells
Remember when, in biology class, we were taught that animal and plant cells had little organelles in them – like chloroplasts or mitochondria – and bacteria lacked those? And how that fact made bacteria feel a bit less special?
It turns out bacteria have their own counterparts, called bacterial microcompartments (or BMCs for short).
And, in a feat that took about two years to accomplish, Cheryl Kerfeld and her lab have seen the fine details of the shells that make up these bacterial organelles, which function as the organisms’ nano-factories.
The results, led by Michigan State University are featured in the current issue of Science.
“We’ve produced a detailed snapshot – at atomic-level resolution – of the membrane of bacterial organelles,” says Cheryl Kerfeld the Hannah Distinguished Professor of Structural Bioengineering at the MSU-DOE Plant Research Lab. “By seeing the intact bacterial organelle shell, we now understand how the basic building blocks are put together to construct the organelle membrane.”
Markus Sutter, co-author says, “It is like you see something kind of blurry. You put glasses on, and then you see it all clear. This is really exciting. This is what we have been looking to do for years.”
The structure described is likely to become the textbook model of the membrane of primitive bacterial organelles, Kerfeld says.
Why this is important: BMCs for nanotechnologies
BMCs are used differently across a diverse range of bacteria. Some pathogenic bacteria use them to outcompete “good” bacteria, while others use BMCs to create energy compounds through photosynthesis.
But the protein shells that make up BMCs are fundamentally the same. And now that Kerfeld and her team can see a BMC structure, it makes it easier to understand how BMCs work and target them for medical or renewable energy applications.
The structure described is likely to become the textbook model of the membrane of primitive bacterial organelles.
“Our results provide the structural basis to design experiments to explain how molecules cross the organelle shell, how specific enzymes are targeted to the inside and how the shells self-assemble,” said Kerfeld, who’s also an affiliate of Lawrence Berkeley National Laboratory.
“This work also provides the foundation to develop therapeutics to disrupt the assembly and function of the BMCs found in pathogens or enhance those that play a role in photosynthesis in order to make fuel molecules, rubber, or plastic.”
The protein, peroxiredoxin Q, is known to maintain a healthy balance of chemicals and energy levels in chloroplasts. The new research shows the protein also impacts the system that produces chloroplast membranes.
The CAMTA system - which is known to protect plants from cold weather - plays a newly discovered role: when bacteria invade a leaf, CAMTA warns neighboring, unaffected leaves to prepare for invasion.
When algae get stressed, they hibernate and store energy in forms that we can use to make biofuels. Understanding how stress impacts algal hibernation could help scientists lower the cost of biofuels production.