Physarum polycephalum : "blood" circulation

[chrisimbee]

Hello,

I have several sample of the "Blob" physarum polycephalum in petri dishes and as i'm preparing sclerotium (dried dormant form) i decided to put some pseudopodes under the microscope.

But the thing is that in bright field you dont see much as the creature is quite thick so I thought that maybe I could try with the fluorescence module. I sprayed the plasmodium with a highly diluted solution of orange acridine in volvic water and waited for a whilt for the dye to be absorbed.

Here is the result : the video shows the many nucleus and the circulating cytoplasm going in one direction and then changing direction again...


https://www.youtube.com/watch?v=CYL-A7n ... chrisimbee


Chris

[Sir]

Beautiful capture! I had no idea that their internals were so animated. Always assumed they were fairly static. Do you have any tips on finding or preparing slime mold for brightfield? Would love to find some myself

[chrisimbee]

Hello Sir, thank you very much

in fact I have no protocol and I just put the petri dish without its lid on the stage and used the X10 objective. But you can do the same in bright field .

In fact the easiest way would be to make an agar plate in a smal petri dish but with a very thin layer eg 1mm thick maximum and then inoculate with a tiny sample from a already settled culture.

As an idea you could pour some diluted solution of neutral red a few minutes before observation or just watch it raw without any dye.

Another idea that comes to my mind would be to do the culture on a slide in a humid chamber on a tiny very thin layer of agar smeared like you would for a blood smear.

As you can see we have to imagine protocols and test them.

My test here was with a dying blob as i was transplanting and preparing sclerotia. I once (a few weeks ago) briefly watched my very first culture under the microscope and the trafic was far more intense but i was told that light could kill the blob i didnt want to carry on until I had more subculture ready.

In fact it more likely that its the UV that are involved in the killing of the plasmodium. And from the many publications I read on line plasmodium has similar pigments to plants like phytochome that can react to blue light and far red and induce it to turn into fructification mode. That explains why we keep the cultures in the dark.

Still one of my culture has turned into fructification and i have spores of physarum polycephalum now and i'm planning to try to germinate then and to get the fusion and maybe get newly formed plasmodium if ever i get successfull!!