10.6084/m9.figshare.3843234.v1
Noboru Katayama
Noboru
Katayama
Kobayashi Makoto
Kobayashi
Makoto
Osamu Kishida
Osamu
Kishida
Electronic supplementary materials from An aquatic vertebrate can use amino acids from environmental water
The Royal Society
2016
aquatic animal
dissolved organic nitrogen uptake
nutrient flow
growth rate
Hynobius retardatus
stable isotope
2016-09-21 06:05:52
Journal contribution
https://rs.figshare.com/articles/journal_contribution/Electronic_supplementary_materials_from_An_aquatic_vertebrate_can_use_amino_acids_from_environmental_water/3843234
Conventional food-web theory assumes that nutrients from dissolved organic matter are transferred to aquatic vertebrates via long nutrient pathways involving multiple eukaryotic species as intermediary nutrient transporters. Here, using larvae of the salamander <i>Hynobius retardatus</i> as a model system, we provide experimental evidence of a shortcut nutrient pathway by showing that <i>H. retardatus</i> larvae can use dissolved amino acids for their growth without eukaryotic mediation. First, to explore which amino acids can promote larval growth, we kept individual salamander larvae in one of eight different high-concentration amino acid solutions, or in control water from which all other eukaryotic organisms had been removed. We thus identified five amino acids (lysine, threonine, serine, phenylalanine and tyrosine) as having the potential to promote larval growth. Next, using <sup>15</sup>N-labelled amino acid solutions, we demonstrated that nitrogen from dissolved amino acids was found in larval tissues. These results suggest that salamander larvae can take up dissolved amino acids from environmental water to use as an energy source or a growth-promoting factor. Thus, aquatic vertebrates as well as aquatic invertebrates may be able to use dissolved organic matter as a nutrient source.