Monday, April 27, 2009

Yeast Cell Monday


Now that I've got a live sourdough starter residing in my refrigerator, I have to remember to feed it once a week. And since that process involves removing some of the old starter, I'm going to try to bake with it, rather than just toss it out. Last week's waffles were not universally loved. (For some, "tangy" and "waffles" apparently don't go together.) So I will try some more bread, which was much more popular. In fact, I could see how it could become addicting.

Anyway, the yeast posts the kids put together left out a look at yeast cells. So here they are. Yeast cells are jelly-bean shaped. At the top left is an electron microscope photo of yeast cells dividing from Science Image in Australia. The diagram at right is from a bread baking webpage.

These two photos were taken with our microscope at 400X magnification. To the left is a digitally-enhanced photo of storeboughten baker's yeast. If you click on it, you can see it large enough to pick out the nuclei in some of the cells. To the right is the wild sourdough yeast we captured in our kitchen.

Why yeast cells are interesting, from the Howard Hughes Medical Institute:
Key findings about human genes have come from studying the humble, blob-like cells of baker's or brewer's yeast, which one researcher calls, shockingly, our relatives. In 1996, yeast became the first eukaryote (an organism whose genetic material is enclosed in a cell nucleus) to have its entire genome sequenced. Ever since, it has remained at the forefront of research on genetics. Almost everything we know about the cell-division cycle, for instance, comes from experiments with yeast, and many new methods of analyzing genes were first tried out in yeast.
Some more resources on yeast cells:

The University of Sidney in Australia's website on fungi.

2 comments:

bulentcan said...

DEAR KATTY
CAN YOU PLS INFORM ME IF YOU KNOW A SIMPLE METHODE TO GET BETA GLUCAN FROM YEAST CELL WALLS.
REGARDS
BULENT

Antonio said...

It's funny how some things that seem so simple have so much incredible things in the background, like who would think that making a bread has so much to do with life.