title: Electron microscopy of the rumen ciliate Entodinium caudatum, with special reference to the engulfment of bacteria and other particulate matter.
abstract: A study in the electron microscope of thin sections of the rumen ciliate Entodinium caudatum was undertaken in an attempt to elucidate the mode of engulfment of particulate matter. This protozoon engulfed bacteria, polystyrene latex particles and olive oil into membrane-lined vesicles in the protozoal endoplasm. Particles of palladium black were also taken up into the endoplasm, but due to the toxic nature of this material it was not possible to demonstrate vesicle formation with certainty. The initial uptake of bacteria may be into large sacs containing many organisms which were subsequently taken into the endoplasm in vesicles that contained only one bacterium each. The evidence obtained in this investigation has been used to distinguish between two different mechanisms for the digestion of bacteria and utilization of the amino acids from the bacterial protein for the synthesis of protozoal protein.
authors.affiliation: A.R.C. Institute of Animal Physiology, Babraham, Cambridge.
authors.forename: G S
authors.initials: GS
authors.lastname: Coleman
authors.forename: F J
authors.initials: FJ
authors.lastname: Hall