There is constant work carried out to make this process more efficient and less costly as of course profits can be maximised and product costs cut.
|Long threads of filamentous fungus|
Individual threads also tend to break in rapidly circulating media, killing some threads and thus reducing yield.
In order to alleviate these problems it would be helpful if we could change the fungus to grow as much shorter threads. Research has shown that the long threads are encouraged by genes responsible for polarized growth. In its natural environment these genes would be used to direct growth towards food without wasting energy going off in other directions! In a bioreactor these genes are not needed as the fungus is always surrounded by food.
This recent paper shows us the results of switching off the polarizing genes in Aspergillus when using it in a bioreactor. The fungus now grows as small pellets rather than long threads and remarkably production of the commercial enzyme has increased by over 80%. It isn't difficult to see the importance of this discovery - cheaper products, less waste, cheaper to manufacture.