A diatom cell and surrounding bacteria

After being collected from a paddy field, the sample was put on DNB agar plate (diluted nutrient broth with agar) with a drop of distilled water for 4 days, and then observed. A large diatom cell slowly goes into and later backs out of a large aggregate. Long filamentous and rod-shaped bacteria are moving around. Some of the rod-shaped bacteria seem to gather around the rear of the diatom cell.

Commentary by Prof. Yuji Tsukii, Hosei University
This diatom belongs to genus Pinnularia.

http://protist.i.hosei.ac.jp/PDB/Im.....

The organism is seen from the side view (girdle face), which does not show the pattern. We can’t be sure from this video whether or not the organism is in the process of division.

Flagellates vigorously swimming around are probably Trachelomonas volvocina.

http://protist.i.hosei.ac.jp/PDB/Im.....

Sampling Date : 22 September 2006

Sampling Site : KASHIMADAI paddy field  Google Map