Effect of Marine-Derived Ice-Binding Proteins on the Cryopreservation of Marine Microalgae

• Published in: Marine Drugs
• Main Authors: Hak Jun Kim, Bon-Won Koo, Doa Kim, Ye Seul Seo, Yoon Kwon Nam
• Format: Article in Journal/Newspaper
• Language: English
• Published: MDPI AG 2017
• Subjects: ice-binding proteins; ice recrystallization inhibition; cryoprotectant; slow-freezing; Isochrysis galbana; Pavlova viridis; Chlamydomonas coccoides; Biology (General); QH301-705.5; Arctic; Antarctic; Pavlova; Antarc*; Sea ice
• Online Access: https://doi.org/10.3390/md15120372; https://doaj.org/article/ee2d090abb364873be62704ea505a966

Ice-binding protein (IBPs) protect cells from cryo-injury during cryopreservation by inhibiting ice recrystallization (IR), which is a main cause of cell death. In the present study, we employed two IBPs, one, designated LeIBP from Arctic yeast, and the other, designated FfIBP from Antarctic sea ice bacterium, in the cryopreservation of three economically valuable marine microalgae, Isochrysis galbana, Pavlova viridis, and Chlamydomonas coccoides. Both of the IBPs showed IR inhibition in f/2 medium containing 10% DMSO, indicating that they retain their function in freezing media. Microalgal cells were frozen in 10% DMSO with or without IBP. Post-thaw viability exhibited that the supplementation of IBPs increased the viability of all cryopreserved cells. LeIBP was effective in P. viridis and C. coccoides, while FfIBP was in I. galbana. The cryopreservative effect was more drastic with P. viridis when 0.05 mg/mL LeIBP was used. These results clearly demonstrate that IBPs could improve the viability of cryopreserved microalgal cells.