There are several references to the light responses of free living
amoebae in the classic work 'The Biology of Amoeba' edited by KW Jeon.
The chapters by Bovee and Jahn (8. Locomotion and behavior) and Allen
(7. Biophysical aspects of pseudopodium formation and retraction)
contain the information and citations. Unfortunately, this book was
published in 1973 and I am not familiar with any more recent work on
the subject. However, I am totally unaware of any evidence that
Entamoeba has any light responses of any kind as implied by the
subject line of your message. Being an intestinal parasite I doubt it
sees much light!
Graham
