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Viruses with more than 1,000 genes: Mamavirus, a new Acanthamoeba polyphaga mimivirus strain, and reannotation of Mimivirus genes.

ABSTRACT: The genome sequence of the Mamavirus, a new Acanthamoeba polyphaga mimivirus strain, is reported. With 1,191,693 nt in length and 1,023 predicted protein-coding genes, the Mamavirus has the largest genome among the known viruses. The genomes of the Mamavirus and the previously described Mimivirus are highly similar in both the protein-coding genes and the intergenic regions. However, the Mamavirus contains an extra 5'-terminal segment that encompasses primarily disrupted duplicates of genes present elsewhere in the genome. The Mamavirus also has several unique genes including a small regulatory polyA polymerase subunit that is shared with poxviruses. Detailed analysis of the protein sequences of the two Mimiviruses led to a substantial amendment of the functional annotation of the viral genomes.

SUBMITTER: Colson P

PROVIDER: S-EPMC3163472 | biostudies-literature | 2011

REPOSITORIES: biostudies-literature

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Viruses with more than 1,000 genes: Mamavirus, a new Acanthamoeba polyphaga mimivirus strain, and reannotation of Mimivirus genes.

Colson Philippe P Yutin Natalya N Shabalina Svetlana A SA Robert Catherine C Fournous Ghislain G La Scola Bernard B Raoult Didier D Koonin Eugene V EV

Genome biology and evolution 20110624

The genome sequence of the Mamavirus, a new Acanthamoeba polyphaga mimivirus strain, is reported. With 1,191,693 nt in length and 1,023 predicted protein-coding genes, the Mamavirus has the largest genome among the known viruses. The genomes of the Mamavirus and the previously described Mimivirus are highly similar in both the protein-coding genes and the intergenic regions. However, the Mamavirus contains an extra 5'-terminal segment that encompasses primarily disrupted duplicates of genes pres ...[more]

PMID: 21705471

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