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, Penrose and Y. Gourbiere for help in the manual annotation of O. mediterraneus and visual inspection of TEM screens. We would like to apologize for the relevant references we could not include because of space limitations. Funding: This research was funded by the ANR grants REVIREC, Author contributions: All molecular biology experiments on microalga and virus were performed at OOB

J. G. , J. A. , S. R. Oob-(m, S. Y. , N. G. et al., Competing interests: The authors declare that they have no competing interests. Data and materials availability: The genome sequence for O. mediterraneus RCC2590 and OmV2 can be found under GenBank accession numbers WMKK00000000 and MN688676, respectively. The complete gene annotations of RCC2590 can be accessed on ORCAE, BpV1 (HM004432.1), BpV2 (HM004430.1), MpV1 (HM004429.1), OtV1 (FN386611.1), OtV2 (FN600414.1), OtV5 (EU304328.2), OtV6 (JN225873.1), OlV1 (HM004431.1), OlV2 (KP874736.1), OlV3 (HQ633060.1), OlV4 (JF974316.1), OlV5 (HQ632827.1), OlV6 (HQ633059.1), OlV7 (KP874737.1), and OmV1 (KP874735.1)

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