WAR  of  the  MICROWORLDS  

How do I kill Thee?   Let me count the Ways!   (# 12)  click here for full list

'Amoebophilus simplex,   Amoebae feed on funguus spores.  As the amoeba is attempting to ingest a spore of Amoebophilus the spore 'sticks' to the outer membrane of the amoeba.    The spore is then stimulated to germinate and penetrates the host membrane by a narrow peg.  Inside the host, the fungus produces a lobed haustorium (feeding structure) to extract nutrients, and then produces chains of asexual spores to the exterior'.  In late stages of infection as the amoeba is dying the fungus produces  thick-walled resistant sexual spores (below right).   ZYGOMYCOTA

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                      A  spore (conidium) of the fungus sticks to the outer membrane of the amoeba.  A narrow peg from this primary attack spore penetrates into the body.  A triangular (in section), lobed haustorium (feeding cell) develops from the penetration peg.   Food is channeled  from the amoeba through the haustorium into the primary attack spore and a branching chain of new spores develops from the outer end  of this spore.    The living amoeba still feeds and moves around and  trails the chain of spores behind it like a tail.    Eventually the fungus sucks the amoeba dry and it shrivels up and dies.   As it is moving along some of the spores from the chain break off and lie around to attack other individual amoebae.  This process is facilitated by the fact that amoebae normally engulf and digest fungus spores as a food source.  In is case the tables have been turned and Amoebophilus has evolved to take advantage of this form of predation by amoebae.  There are only three species of Amoebophilus known and   so probably many more remain to be discovered.   They are possibly host specific and the one I found attacked only one of the several species of amoebae present in the original culture.

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Amoebophilus simplex growing on aboeboid host.  Ameoba has two 'fried egg' nuclei and was preparing to divide at the time of attack.

 

Images copyright George Barron from MycoAlbum CD

Comment on MycoaAlbum CD by NA

  'Very impressed by the high quality of the pictures and the very clear accounts' - from Japan!