Nom du corpus

Corpus Systématique Animale

Titre du document

Differential survival of Venus gallina and Scapharca inaequivalvis during anoxic stress: Covalent modification of phosphofructokinase and glycogen phosphorylase during anoxia

Lien vers le document
Éditeur
Springer (journals)
Langue(s) du document
Anglais
Type de document
Research-article
Mots-clés d'auteur
  • Anaerobiosis
  • Glycolytic control
  • Phosphofructokinase
  • Glycogen phosphorylase
  • Molluscs
  • EDTA : ethylenediaminetetraacetic acid
  • EGTA : ethyleneglycol-bis-(2-aminoethyl)-tetraacetic acid
  • Fructose-2,6-P 2 : fructose-2,6-bisphosphate
  • Fructose-6-P : fructose-6-phosphate
  • K a AMP : Activation constant (concentration of AMP required to increase the reaction to twice the rate it shows in the absence of AMP)
  • MATP : ATP turnover rate
  • P i : inorganic phosphate
  • PCA : Perchloric acid
  • PFK : 6-phosphofructo-1-kinase
  • TCA : Trichloroacetic acid
Nom du fichier dans la ressource
Mollusques_v2b_00739
Auteur(s)
  • S. P. J. Brooks 1
  • A. de Zwaan 1
  • G van den Thillart 1
  • O. Cattani 1
  • P. Cortesi 1
  • K. B. Storey 1
Affiliation(s)
  • 1) Consorzio di Studi, Ricerche ed Interventi sulle Risorse Marine, Viale Amerigo Vespucci 2, I-47042, Cesenatico, FO, Italy
Résumé

Biochemical mechanisms underlying anaerobiosis were assessed in two Mediterranean bivalve species, Scapharca inaequivalvis and Venus gallina, with widely differing tolerances for oxygen lack. These species displayed LT50 values for anoxic survival at 17–18°C of 17 and 4 d, respectively. Succinate and alanine were the major products of 24 h anaerobic metabolism in both species but only S. inaequivalvis further metabolized succinate to propionate. Both species reduced metabolic rate while anoxic but metabolic arrest was more pronounced in S. inaequivalvis. Calculated ATP turnover rate (MATP) during exposure to N2-bubbled seawater was only 4.51% of the aerobic rate in S. inaequivalvis but was 12.68% in V. gallina. To counteract a greater load of acid end products, V. gallina foot showed a significantly greater buffering capacity, 23.38±0.20 slykes, compared to 19.6±0.79 slykes in S. inaequivalvis. The two species also differed distinctly in the enzymatic regulation of anaerobiosis. In V. gallina anoxia exposure caused only a small change in PFK kinetic parameters (a decrease in Ka AMP) and had no effect on glycogen phosphorylase. By contrast, S. inaequivalvis foot showed a strong modification of enzyme properties in anoxia. The percentage of glycogen phosphorylase in the a form dropped significantly only in S. inaequivalvis. Other changes included alterations in the properties of PFK leading to a less active enzyme form in anoxia. Compared to the aerobic enzyme form, PFK from anoxic foot showed a reduced affinity for fructose-6-P (Km increased 2.4-fold), greater inhibition by ATP (I50 decreased 6.8-fold), and an increase in sensitivity to AMP activation (Ka decreased by 50%). These enzyme changes appear to be key to a glycolytic rate depression during anaerobiosis in S. inaequivalvis foot muscle.

Catégories Science-Metrix
  • 1 - health sciences
  • 2 - biomedical research
  • 3 - physiology
Catégories INIST
  • 1 - sciences appliquees, technologies et medecines
  • 2 - sciences biologiques et medicales
  • 3 - sciences biologiques fondamentales et appliquees. psychologie
Catégories Scopus
  • 1 - Life Sciences ; 2 - Biochemistry, Genetics and Molecular Biology ; 3 - Endocrinology
  • 1 - Life Sciences ; 2 - Agricultural and Biological Sciences ; 3 - Animal Science and Zoology
  • 1 - Life Sciences ; 2 - Biochemistry, Genetics and Molecular Biology ; 3 - Biochemistry
  • 1 - Life Sciences ; 2 - Agricultural and Biological Sciences ; 3 - Ecology, Evolution, Behavior and Systematics
  • 1 - Life Sciences ; 2 - Biochemistry, Genetics and Molecular Biology ; 3 - Physiology
Catégories WoS
  • 1 - science ; 2 - zoology
  • 1 - science ; 2 - physiology
Identifiant ISTEX
0D9CCFC6EA3FA30E7830D6713045377A5FF59C6B
Revue

Journal of Comparative Physiology B

Année de publication
1991
Présence de XML structuré
Non
Version PDF
1.3
Score qualité du texte
10
Sous-corpus
  • Mollusques
Type de publication
Journal
ark:/67375/1BB-1PBLD26D-M
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