Bacterial diversity at a shallow-water hydrothermal vent (Espalamaca) in Azores Island

Abstract

A low-temperature shallow-water hydrothermal vent field was discovered during the summer of 2010 in the Faial-Pico channel off the Espalamaca headland, Faial Island, Azores, Portugal, NE Atlantic. The present study analyses bacterial communities present in shallowwater hydrothermal vent of Espalamaca using SSU rRNA-based clone library approach. Clones of shallow vent sediment sample revealed the dominance of Proteobacteria (including α, γ, ε, δ, ζ subdivisions) and Bacteroidetes with 36% and 28% of the whole community respectively. The dominance of γ-Proteobacteria is the unique characteristic of this shallow vent and it coincides with the South Tonga Arc and Bahía Concepción (Pacific Ocean), whereas ε- Proteobacteria groups were reported to be high in the majority of the hydrothermal vents. Though the sampling sites of the venting and non-venting regions of Espalamaca were only 500 m apart, high variation (> 80%) of phylotypes was found between the regions.