Metabolic enzyme activities in swimming muscle of medusae: is the scaling of glycolytic activity related to oxygen availability?

Autor:	Kelly D. McCullough, Erik V. Thuesen, James J. Childress
Rok vydání:	2005
Předmět:	Cnidaria Periphylla periphylla biology Mesopelagic zone Hypoxia (environmental) Aquatic Science biology.organism_classification chemistry.chemical_compound Biochemistry chemistry Lactate dehydrogenase biology.protein Aurelia labiata Citrate synthase Coelenterata
Zdroj:	Journal of the Marine Biological Association of the United Kingdom. 85:603-611
ISSN:	1469-7769 0025-3154
DOI:	10.1017/s0025315405011537
Popis:	This study compared the scaling of the glycolytic enzyme lactate dehydrogenase (LDH) and the Krebs cycle enzyme citrate synthase (CS) in the swimming muscle and tentacle tissue of the mesopelagic coronate scyphomedusa Periphylla periphylla in two populations living under different oxygen minimum layer conditions. The LDH and CS activities in these tissues of two other coronate scyphomedusae (Paraphyllina ransoni and Periphyllopsis galatheae) and the bathypelagic narcomedusa Aegina citrea were also studied. The scaling of these two enzymes along with total protein was investigated in whole organism homogenates of the surface-living scyphomedusa Aurelia labiata. Mass-specific LDH activities in swimming muscle showed positive scaling in relation to body size in Periphylla periphylla collected off California and Hawaii. Mass-specific LDH activities in tentacle tissue increased with regards to increasing mass only in specimens of P. periphylla collected off California. The LDH values of the scaling coefficient, b, in swimming muscle and tentacle were significantly higher in P. periphylla collected in the low oxygen waters off California than from those collected off the Hawaiian Islands in a higher oxygen environment. The LDH showed a significant decrease with body size in Aegina citrea swimming muscle and in Aurelia labiata whole animal homogenates. The largest species in this study, Periphyllopsis galatheae, had LDH activities similar to the smallest specimens of Periphylla periphylla. The results of this study suggest that the scaling of glycolytic activity is related to oxygen availability for P. periphylla. In Aurelia labiata, which is only exposed to episodic hypoxia, and Aegina citrea, scaling of glycolytic activity is not affected by oxygen availability.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::9b576c4de0b9935f7b350c542a9fd7d9 https://doi.org/10.1017/s0025315405011537 Zobrazit plný text záznamu