The negatively charged protein extracted from Tetrahymena pyriformis as an attractant in Amoeba proteus chemotaxis

Abstract

We extracted a pure protein from T e t r a h y m e n a pyriformis as the chemotactic substance in Amoeba proteus. The protein was heat-stable, negatively charged at neutral pH (since its isoelectric point was near pH 4.5) and composed of three subunits. Its molecular weight was 3 X 8,000.

Effects of Chemical Substances on Rate of Locomotion in the Amoeba Mayorella penardi1

“…M riety of proteins and peptones act as inducers of a feeding response in amoebae (2,7,(8)(9)(10). On the other hand, Nohmi & Tawada (5) showed that a certain negatively charged protein (MW 24,000) extracted from Tetrahymena pyriformis functions as a chemotactic substance for Amoebaproteus. They also stated that most other proteins were not chemical attractants for the amoeba and could not induce pseudopodium formation.…”

Chemosensory responses of a protozoan are modified by antitubulins

“…The importance of chemosensory responses in the ecology of aquatic microorganisms is seen in a number of recent studies (3,7,11). We have developed a method of observing behavioral responses to various chemicals by the heterotrophic marine dinoflagellate Crypthecodinium (Gyrodinium) cohnii, Puerto Rican strain, a free-living saprophyte often seen in samples of decomposing seaweeds (8) and the subject of nutritional and other studies (9).…”