Uncoupled viral and bacterial distributions in coral reef waters of Tuamotu Archipelago (French Polynesia)

Bouvy, Marc; Combe, Marine; Bettarel, Yvan; Dupuy, Christine; Rochelle-Newall, Emma; Charpy, Loïc

Uncoupled viral and bacterial distributions in coral reef waters of Tuamotu Archipelago (French Polynesia)

2012

This study examined the distribution of virioplankton and bacterioplankton in two coral reef systems (Ahe and Takaroa atolls) in the Tuamotu Archipelago, in comparison with the surrounding oligotrophic ocean. Mean concentrations of 4.8×10⁵ and 6.2×10⁵cellsml⁻¹ for bacteria and 8.1×10⁶ and 4.3×10⁶VLP(virus-like particle) ml⁻¹ were recorded in Ahe and Takaroa lagoons, respectively. Chlorophyll-a concentrations and dissolved organic matter were higher in Ahe whereas ³H thymidine incorporation rates were higher in Takaroa. First data on lytic and lysogenic strategies of phages in coral reef environments were discussed in this paper. The fraction of visibly infected cells by viruses was negligible regardless of the lagoon station (mean=0.15%). However, the fraction of lysogenic cells ranged between 2.5% and 88.9%. Our results suggest that the distribution patterns of virioplankton are apparently not coupled to the spatial dynamics of the bacterioplankton communities.

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