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Viral clones from the GOS expedition with an unusual photosystem-I gene cassette organization.

ABSTRACT: Cyanobacteria have a key role in marine photosynthesis, which contributes to the global carbon cycle and to the world oxygen supply. Genes encoding for photosystem-II (PSII) and photosystem-I (PSI) reaction centers are found in different cyanophage genomes, and it was suggested that the horizontal transfer of these genes might be involved in increasing phage fitness. We have further analyzed a rare viral Global Ocean Sampling (GOS) clone containing PSI genes. This clone contains the unusual PSI gene organization psaD->C->A, as opposed to the more frequently observed viral psaJF->C->A->B->K->E->D organization, and was detected only once in the GOS metagenome. Our analyses identified more occurrences with similar arrangement and indicate that this PSI viral gene organization (now psaD->C->A->B), although rare, is authentic and represents a new PSI gene arrangement.

SUBMITTER: Beja O

PROVIDER: S-EPMC3400403 | biostudies-literature | 2012 Aug

REPOSITORIES: biostudies-literature

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Viral clones from the GOS expedition with an unusual photosystem-I gene cassette organization.

Béjà Oded O Fridman Svetlana S Glaser Fabian F

The ISME journal 20120329 8

Cyanobacteria have a key role in marine photosynthesis, which contributes to the global carbon cycle and to the world oxygen supply. Genes encoding for photosystem-II (PSII) and photosystem-I (PSI) reaction centers are found in different cyanophage genomes, and it was suggested that the horizontal transfer of these genes might be involved in increasing phage fitness. We have further analyzed a rare viral Global Ocean Sampling (GOS) clone containing PSI genes. This clone contains the unusual PSI ...[more]

PMID: 22456446

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