SCIENTISTS IN Cork and Kent have succeeded in making specialised compartments in bacteria that pave the way for a new method for manufacturing medicines, writes BETH O'DONOGHUE
The research proves yet again that the best things really do come in small packages. “The way it works is that bacteria can be manipulated to construct internal pockets inside themselves that work as mini factories (bioreactors) where biofuels and medicines could be produced,” says Prof Michael Prentice, professor of microbiology at University College Cork who led the Cork-based research.
Animal and plant cells have built-in structures called organelles, which keep different cell reactions separated. Being smaller and less complex than human cells, most bacteria do not contain these microcompartments, Prentice explains.
Researchers in Ireland funded by Science Foundation Ireland, and at the University of Kent by the UK Biotechnology and Biological Sciences Research Council, cloned specific genes into E colibacteria which cannot naturally produce the microcompartments.
The E colicould then produce empty microcompartments that consisted only of a protein shell. The scientists managed to produce individual microcompartments that filled up to 70 per cent of the bacterial cell's total volume.
Bacteria are already used as inexpensive and effective factories for chemicals and medicines ranging from insulin to food preservatives. The production of these microcompartments is particularly exciting because they separate specific reactions away from the rest of the cell’s activities, Prentice explains.
This increases efficiency when using the microcompartment because it prevents interactions with other compounds in the cell. It also makes it easier for scientists to target and manipulate specific processes. Having these microcompartments enables bacteria to produce toxic substances such as antibiotics that are too harmful to be produced in the main bacterial cell area.
As the scientists write: “The [microcompartment] meets all the criteria required of a nanoscale bioreactor.” This includes their minute size, the ability to keep the manufactured substance in one area and preventing the substance from being contaminated by the rest of the cell contents.
For all these reasons, the study’s success in creating empty microcompartments has very exciting implications for the Irish biotechnology industry. Products produced in these “mini factories” may include vitamins, medicines and designer chemicals, he says.
A solution to the looming energy crises may also be held within these bacterial pockets. The production of energy products such as ethanol and hydrogen gas in the microcompartments would reduce our dependency on oil- based products, he suggests.
Prentice points to Lactobacillus reuterias another promising bacterium offering possibilities for future research. Under very specific circumstances, L reuteriforms these microcompartments by itself, using them to produce antibacterial compounds. These antibacterial substances are produced to kill other bacteria competing with L reuterifor nutrients.
It is expected that further studies will enable scientists to develop medicines for humans using similar methods, he says. “The next step forward is to investigate the shape of these compartments and how theyre assembled,” says Prentice.