Enzymes of energy metabolism in hatchlings of amazonian freshwater turtles (Testudines, Podocnemididae)
The metabolic profiles of selected tissues were analyzed in hatchlings of the Amazonian freshwater turtles Podocnemis expansa, P. unifilis and P. sextuberculata. Metabolic design in these species was judged based on the key enzymes of energy metabolism, with special emphasis on carbohydrate, lipid,...
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doaj-07bb770aa56a4cffb03ec832724c02392020-11-24T21:00:39ZengInstituto Internacional de EcologiaBrazilian Journal of Biology1678-437569231932510.1590/S1519-69842009000200012S1519-69842009000200012Enzymes of energy metabolism in hatchlings of amazonian freshwater turtles (Testudines, Podocnemididae)WP. Duncan0JL. Marcon1Universidade Federal do AmazonasUniversidade Federal do AmazonasThe metabolic profiles of selected tissues were analyzed in hatchlings of the Amazonian freshwater turtles Podocnemis expansa, P. unifilis and P. sextuberculata. Metabolic design in these species was judged based on the key enzymes of energy metabolism, with special emphasis on carbohydrate, lipid, amino acid and ketone body metabolism. All species showed a high glycolytic potential in all sampled tissues. Based on low levels of hexokinase, glycogen may be an important fuel for these species. The high lactate dehydrogenase activity in the liver may play a significant role in carbohydrate catabolism, possibly during diving. Oxidative metabolism in P. sextuberculata appears to be designed for the use of lipids, amino acids and ketone bodies. The maximal activities of 3-hydroxyacyl-CoA dehydrogenase, malate dehydrogenase, glutamine dehydrogenase, alanine aminotransferase and succinyl-CoA keto transferase display high aerobic potential, especially in muscle and liver tissues of this species. Although amino acids and ketone bodies may be important fuels for oxidative metabolism, carbohydrates and lipids are the major fuels used by P. expansa and P. unifilis. Our results are consistent with the food habits and lifestyle of Amazonian freshwater turtles. The metabolic design, based on enzyme activities, suggests that hatchlings of P. unifilis and P. expansa are predominately herbivorous, whereas P. sextuberculata rely on a mixed diet of animal matter and vegetation.http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1519-69842009000200012&lng=en&tlng=enamazonian freshwater turtlesPodocnemisenergy metabolism |
collection |
DOAJ |
language |
English |
format |
Article |
sources |
DOAJ |
author |
WP. Duncan JL. Marcon |
spellingShingle |
WP. Duncan JL. Marcon Enzymes of energy metabolism in hatchlings of amazonian freshwater turtles (Testudines, Podocnemididae) Brazilian Journal of Biology amazonian freshwater turtles Podocnemis energy metabolism |
author_facet |
WP. Duncan JL. Marcon |
author_sort |
WP. Duncan |
title |
Enzymes of energy metabolism in hatchlings of amazonian freshwater turtles (Testudines, Podocnemididae) |
title_short |
Enzymes of energy metabolism in hatchlings of amazonian freshwater turtles (Testudines, Podocnemididae) |
title_full |
Enzymes of energy metabolism in hatchlings of amazonian freshwater turtles (Testudines, Podocnemididae) |
title_fullStr |
Enzymes of energy metabolism in hatchlings of amazonian freshwater turtles (Testudines, Podocnemididae) |
title_full_unstemmed |
Enzymes of energy metabolism in hatchlings of amazonian freshwater turtles (Testudines, Podocnemididae) |
title_sort |
enzymes of energy metabolism in hatchlings of amazonian freshwater turtles (testudines, podocnemididae) |
publisher |
Instituto Internacional de Ecologia |
series |
Brazilian Journal of Biology |
issn |
1678-4375 |
description |
The metabolic profiles of selected tissues were analyzed in hatchlings of the Amazonian freshwater turtles Podocnemis expansa, P. unifilis and P. sextuberculata. Metabolic design in these species was judged based on the key enzymes of energy metabolism, with special emphasis on carbohydrate, lipid, amino acid and ketone body metabolism. All species showed a high glycolytic potential in all sampled tissues. Based on low levels of hexokinase, glycogen may be an important fuel for these species. The high lactate dehydrogenase activity in the liver may play a significant role in carbohydrate catabolism, possibly during diving. Oxidative metabolism in P. sextuberculata appears to be designed for the use of lipids, amino acids and ketone bodies. The maximal activities of 3-hydroxyacyl-CoA dehydrogenase, malate dehydrogenase, glutamine dehydrogenase, alanine aminotransferase and succinyl-CoA keto transferase display high aerobic potential, especially in muscle and liver tissues of this species. Although amino acids and ketone bodies may be important fuels for oxidative metabolism, carbohydrates and lipids are the major fuels used by P. expansa and P. unifilis. Our results are consistent with the food habits and lifestyle of Amazonian freshwater turtles. The metabolic design, based on enzyme activities, suggests that hatchlings of P. unifilis and P. expansa are predominately herbivorous, whereas P. sextuberculata rely on a mixed diet of animal matter and vegetation. |
topic |
amazonian freshwater turtles Podocnemis energy metabolism |
url |
http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1519-69842009000200012&lng=en&tlng=en |
work_keys_str_mv |
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