title: Ingestion and inactivation of bacteriophages by Tetrahymena.
abstract: Abiotic factors are thought to be primarily responsible for the loss of bacteriophages from the environment, but ingestion of phages by heterotrophs may also play a role in their elimination. Tetrahymena thermophila has been shown to ingest and inactivate bacteriophage T4 in co-incubation experiments. In this study, other Tetrahymena species were co-incubated with T4 with similar results. In addition, T. thermophila was shown to inactivate phages T5 and lambda in co-incubations. Several approaches, including direct visualization by electron microscopy, demonstrated that ingestion is required for T4 inactivation. Mucocysts were shown to have no role in the ingestion of T4. When (35)S-labeled T4 were fed to T. thermophila in a pulse-chase experiment, the degradation of two putative capsid proteins, gp23(*) and hoc, was observed. In addition, a polypeptide with the apparent molecular mass of 52 kDa was synthesized. This suggests that Tetrahymena can use phages as a minor nutrient source in the absence of bacteria.
authors.affiliation: Department of Biology and Health Services, Edinboro University of Pennsylvania, Edinboro, Pennsylvania 16444, USA.
authors.forename: Wendy
authors.initials: W
authors.lastname: Hennemuth
authors.forename: Laura S
authors.initials: LS
authors.lastname: Rhoads
authors.forename: Henry
authors.initials: H
authors.lastname: Eichelberger
authors.forename: Miki
authors.initials: M
authors.lastname: Watanabe
authors.forename: Kevin M
authors.initials: KM
authors.lastname: Van Bell
authors.forename: Lei
authors.initials: L
authors.lastname: Ke
authors.forename: Hyesuk
authors.initials: H
authors.lastname: Kim
authors.forename: Giang
authors.initials: G
authors.lastname: Nguyen
authors.forename: Jeremy D
authors.initials: JD
authors.lastname: Jonas
authors.forename: Derek
authors.initials: D
authors.lastname: Veith
authors.forename: Craig T
authors.initials: CT
authors.lastname: Van Bell
mesh_terms: D000818:Animals; D017122:Bacteriophage T4 / Q000254:growth & development* / Q000648:ultrastructure; D010582:Bacteriophage lambda / Q000254:growth & development; D036022:Capsid Proteins / Q000378:metabolism; D018920:Coculture Techniques / Q000379:methods; D007553:Isotope Labeling; D008854:Microscopy, Electron; D009154:Mutation; D013462:Sulfur Radioisotopes / Q000378:metabolism; D013604:T-Phages / Q000254:growth & development; D013768:Tetrahymena / Q000235:genetics / Q000502:physiology* / Q000648:ultrastructure / Q000821:virology*; D016808:Tetrahymena thermophila / Q000235:genetics / Q000502:physiology / Q000648:ultrastructure / Q000821:virology; D038301:Virus Inactivation
chemical_list: D036022:Capsid Proteins; D013462:Sulfur Radioisotopes