Thanks to bacteria, nitrogen is also available

2009/11/26 Lakar Iraizoz, Oihane - Elhuyar Zientzia

• Biokimika
• Mikrobiologia
• Zoologia

In addition to the sugars of the leaves, the cutting ants obtain the nitrogen necessary to synthesize proteins and other nitrogenous components in the “microorganism gardens” they contain in their sludges. A group of biologists from the University of Wisconsin have found that in these nurseries of bacteria and fungi that make edible leaves for ants there are two genera of bacteria that fix atmospheric nitrogen.

Leaf cutting ants would not have the way to feed on the cutting leaves if they did not have these special vegetable gardens in the dens. In fact, the microorganisms of these gardens, especially the fungi, process the leaves that carry the ants and leave them digested, giving shape to a white paste. There are also bacteria that produce antibiotics to protect fungi and ants in exchange for food.

However, the leaves are very poor in nitrogen and in an experiment to find out where this essential ingredient is obtained, the researchers of Wisconsin have discovered that in these fertile gardens there are also nitrogen fixing bacteria. As one researcher who has participated in the study told the journal Science, "these vegetable gardens are true digestive systems."

Image: Image: Michael Poulsen, © Science