Cryopreservation of Holospora undulata, a bacterial parasite of the ciliate Paramecium caudatum.
We investigated cryopreservation of horizontal transmission stages of Holospora undulata, a micronucleus-specific bacterial parasite of Paramecium caudatum. Unlike in previous studies on related Holospora species, protocols using glycerol as cryoprotectant failed entirely. In contrast, freezing with dimethyl sulfoxide (Me2SO) conserved infectiousness of nearly all replicate inocula, although infection success was considerably lower than that of fresh inocula. Infection probability was enhanced by increasing the Me2SO concentration from 5 to 10%, and by freezing at -196 degrees C rather than -80 degrees C. Prolonged storage of up to 3 months had no significant effect on the viability of the inocula.
Millot
Laurence
L
Laboratoire de Parasitologie Evolutive, CNRS UMR 7103, CC 237, Université Pierre and Marie Curie, 7 Quai St-Bernard, 75252 Paris Cedex 05, France.
Kaltz
Oliver
O
D000818:Animals; D015925:Cryopreservation / Q000379:methods*; D003451:Cryoprotective Agents / Q000378:metabolism / Q000494:pharmacology; D004121:Dimethyl Sulfoxide / Q000378:metabolism / Q000494:pharmacology; D005615:Freezing; D005990:Glycerol / Q000378:metabolism / Q000494:pharmacology; D042281:Holosporaceae / Q000472:pathogenicity / Q000502:physiology*; D050296:Microbial Viability / Q000187:drug effects; D048488:Paramecium caudatum / Q000472:pathogenicity / Q000502:physiology*; D010271:Parasites / Q000378:metabolism / Q000472:pathogenicity*; D013696:Temperature; D013997:Time Factors
D003451:Cryoprotective Agents; D005990:Glycerol; D004121:Dimethyl Sulfoxide