Anabaena spec.

ralfwagner · Post by **ralfwagner** » Sat Aug 05, 2006 9:43 am

Hello,

I'm absolutely fascinated by the cyanobacteria. Not only because of their ability to bind nitrogen from the air (the chemists did a long and complicated work before they managed to to this in the Haber-Bosch prozess) and their role in several symbiosis (lichenes, azolla), but mainly because of their role in the endosymbiosis-theory: new species are generated not through progressing mutations over several generations, but by melting two completely different species together.

The following picture shows an Anabaena spec. with cells in different cell-division stages. You can see also the somewhat bigger heterocystis in the middle of the filament. Here the nitrogen processing takes place. At the contact points with the "normal" cells there are two light scattering granules visible. These are the so called pole-bodies. Through these the nitrogen-assimilates are transported to all other cells.

Objective 100x/1,25 Oil

Ken Ramos · Post by **Ken Ramos** » Sat Aug 05, 2006 9:52 am

Interesting narrative and microphotograph Ralf but how are the "pole bodies" formed?

ralfwagner · Post by **ralfwagner** » Sat Aug 05, 2006 12:13 pm

Ken,

I don't know exactly how the pole-bodies are formed. But I suppose the following: The pole-bodies are organelles like the nucleus, the mitochondria and many others. So I suppose that they are formed during the differentiation of a "normal" anabaena-filament-cell to a heterocyst. But maybe that there are experts in this forum who can explain this specific topic better.