Diversity of bacteria and archaea from two shallow marine hydrothermal vents from Vulcano Island

Abstract

To obtain new insights into community compositions of hyperthermophilic microorganisms, defined as having optimal growth temperatures of 80 °C and above, sediment and water samples were taken from two shallow marine hydrothermal vents (I and II) with temperatures of 100 °C at Vulcano Island, Italy. A combinatorial approach of denaturant gradient gel electrophoresis (DGGE) and metagenomic sequencing was used for microbial community analyses of the samples. In addition, enrichment cultures, growing anaerobically on selected polysaccharides such as starch and cellulose, were also analyzed by the combinatorial approach. Our results showed a high abundance of hyperthermophilic archaea, especially in sample II, and a comparable diverse archaeal community composition in both samples. In particular, the strains of the hyperthermophilic anaerobic genera Staphylothermus and Thermococcus, and strains of the aerobic hyperthermophilic genus Aeropyrum, were abundant. Regarding the bacterial community, ε-Proteobacteria, especially the genera Sulfurimonas and Sulfurovum, were highly abundant. The microbial diversity of the enrichment cultures changed significantly by showing a high dominance of archaea, particularly the genera Thermococcus and Palaeococcus, depending on the carbon source and the selected temperature.

Phylogenetic Structure and Metabolic Properties of Microbial Communities in Arsenic-Rich Waters of Geothermal Origin

“…In this study, archaea were found at high abundance in thermal waters, likely due to high temperature and reducing redox conditions ( Rogers and Amend, 2005 ; Antranikian et al, 2017 ). Moreover, in thermal waters, a dominance of OTUs only distantly related to members affiliated to Epsilonproteobacteria , Gammaproteobacteria and Firmicutes was found, thus indicating the occurrence of bacterial biodiversity so far unexplored.…”

The metagenome of bromeliads phytotelma in Puerto Rico

“…Microbial diversity, enzymatic activities and ecological roles of microorganisms in the desired environment can be studied without the necessity of microorganism isolation. Metagenomics have been used for the study of different aquatic environments such as lakes [3] , oceans [4] , rivers [5] , hydrothermal vents [6] and hot springs [7] . New species of non-cultivable microorganisms, enzymes of biomedical and biotechnological value, and new metabolic pathways have been elucidated using metagenomics.…”

The global distribution and evolutionary history of the pT26‐2 archaeal plasmid family

“…The Thermococcales are strictly anaerobic hyperthermophiles (optimal growth temperature > 80°C) that are ubiquitous in hydrothermal vent systems (Zillig et al ., ; Fiala and Stetter, ; Takai et al ., ). The majority of Thermococcales were isolated from marine geothermal environments, both shallow and deep hydrothermal vents, and a few strains were also isolated from continental oil reservoirs (at high temperature and salinity; Ravin et al ., ) and from freshwater terrestrial hot springs (Antranikian et al ., ). The Methanococcales are also strictly anaerobic, but, in contrast to Thermococcales, they are not restricted to high‐temperature environments; Methanocaldococcaceae ( Methanocaldococcus and Methanotorris ) are hyperthermophiles and Methanococcaceae ( Methanococcus and Methanothermococcus ) are either hyperthermophiles or mesophiles (Supporting Information Fig.…”