Do you think these are contractile-vacuole pores?

Charles Krebs · Post by **Charles Krebs** » Sun Feb 27, 2005 9:24 pm

I was watching contractile vacuoles on some paramecium bursaria and noticed that when I shifted focus from the vacuole inside the cell to the cells surface there were always two rounded "ports" in the pellicle directly above the vacuole.

In "1a" you can see the two circular structures on the surface, and in "1b" I have quickly focused "into" the cell to show the full vacuole directly underneath. "2a" and "2b" show the same thing on a different paramecium. I checked about 4 or 5 individuals and found the same.

The inset in the lower left shows these structures with a scale bar. (Lower right shows a whole paramecium bursaria.)

I know you are supposed to be able to see the pores that empty the vacuole contents, but I've never seen them in a picture, and I've never read about two pores for a vacuole. Do you all think this is what these are?

1a, 1b, 2a, 2b, lower left inset taken with Olympus 100X, 3.3X photo-eyepiece, Canon 10D.

Ken Ramos · Post by **Ken Ramos** » Mon Feb 28, 2005 4:10 am

Whoa! Talk about a detailed image! I would guess that, that is what they are Charlie. I have read about them in various articles concerning water expelling vesicles (wev) but have never seen them until now. I would imagine some protozoologist somewhere would like very much to see these. Excellent work here indeed.

Steve West · Post by **Steve West** » Mon Feb 28, 2005 6:53 am

Incredible detail and clarity Charlie! Your explanation sure looks plausible. Are these taken using oblique lighting? Wow--what spectacular images!

Steve

Charles Krebs · Post by **Charles Krebs** » Mon Feb 28, 2005 1:16 pm

Steve... yes these are "slightly" oblique brightfield... fairly small offset. (Except for the full critter shot, which was "rheinberg-oblique"). I really like oblique-brightfield. The biggest problem is that if you go very "strong" oblique you lose color, but you will pick up detail you can't see without it.

Gerd · Post by **Gerd** » Mon Feb 28, 2005 3:36 pm

Charlie, what a wonderful gallery ! I never saw vacuoles emptying so detailed. And i never saw two pores.
That is a question, Prof. Hausmann in Berlin could answer : hausmann@zedat.fu-berlin.de
He is protozoologist and a very kind person, publisher of the Mikrokosmos, the leading
magazine in microscopy in Germany.
Gerd

Mike · Post by **Mike** » Mon Feb 28, 2005 4:08 pm

Hello Charlie,

Do you have any proof that you are from this planet? Your images are 'other worldly' and I figure you are using some alien technology that hasn't been discovered by us Earthlings!

I haven't commented on a lot of the shots you have posted, but please allow me to add my plaudits to the others; well deserved they are.

You have set the benchmark, and then keep raising it! Great work, and as one of the other people mentioned, the level of images being presented on this forum are without equal, and done by "amatuers."

Some amatuers!

All the best,

Mike

piotr · Post by **piotr** » Mon Feb 28, 2005 8:31 pm

Charlie,

Excellent images and pro-level reaearch!

Here I found a following excerpt in the "Biology of Paramecium" book by Ralph Wichterman (The Blakitson Company, 1953, p. 35):

"(...) Kalmus (1931) reports that he has at times been able to observe two pores at one contractile vauole in P. caudatum and King (1935) has seen two in P. aurelia. Kahl (1930) is of the opinion that P. bursaria also possesses two excertion pores for each vacuole."

Charles Krebs · Post by **Charles Krebs** » Tue Mar 01, 2005 12:21 am

Thanks all for the comments.
Piotr... really appreciate the excerpt from the Wichterman book.
I guess, with that reference... Charlie (2005) will now be of the opinion that P. bursaria has two pores for each vacuole too!