title: Analysis of the role of DOP on the particulate phosphatase activity in Toulon Bay (N.W. Mediterranean Sea, France).
abstract: Alkaline phosphatase (AP) activity was studied on homogenates of particulate material in relation to the concentrations of AP-hydrolysable (DOPpa) and AP-non hydrolysable (DOPr) phosphorus. AP activity had high and low Km components. The high affinity activity came from ectoenzymes. It was negatively and significantly correlated with DOPr as with the sum of DIP and DOPr, but not with DOPpa. However negative correlations with DOPpa existed when DIP concentrations decreased. Significant correlations with the sum of DIP and DOPpa attest of additive effects of DIP and DOPpa. The low affinity activity came from "endoenzymes". This activity was also negatively correlated with DOP (DOPpa and DOPr). DOPpa and to a lesser extent DOPr influenced also positively the protein and/or Chlorophyll biomasses of the particulate material. We hypothesize that the correlations of the AP activity with DOP come from regenerated phosphate sequestered in cells and not released in the environment with DIP.
authors: Laboratoire PROTEE-EBMA (EA 3819), Université de TOULON, Avenue de l'Université, BP 20132, F-83957 La Garde Cedex, France. Electronic address: boge@univ-tln.fr.
authors: Gérard
authors: G
authors: Bogé
authors: Laboratoire PROTEE-EBMA (EA 3819), Université de TOULON, Avenue de l'Université, BP 20132, F-83957 La Garde Cedex, France. Electronic address: m_lespilette@yahoo.fr.
authors: Magali
authors: M
authors: Lespilette
authors: Laboratoire PROTEE-EBMA (EA 3819), Université de TOULON, Avenue de l'Université, BP 20132, F-83957 La Garde Cedex, France. Electronic address: d.jamet@univ-tln.fr.
authors: Dominique
authors: D
authors: Jamet
authors: Laboratoire PROTEE-EBMA (EA 3819), Université de TOULON, Avenue de l'Université, BP 20132, F-83957 La Garde Cedex, France. Electronic address: jamet@univ-tln.fr.
authors: Jean-Louis
authors: JL
authors: Jamet
mesh_terms: D000469:Alkaline Phosphatase / Q000378:metabolism*; D061006:Bays; D018533:Biomass; D002734:Chlorophyll / Q000032:analysis; D000077194:Chlorophyll A; D005602:France; D007700:Kinetics; D008522:Mediterranean Sea; D010758:Phosphorus / Q000378:metabolism*; D010933:Plankton / Q000378:metabolism*; D012623:Seawater / Q000737:chemistry* / Q000382:microbiology; D018709:Statistics, Nonparametric
chemical_list: D002734:Chlorophyll; D010758:Phosphorus; D000469:Alkaline Phosphatase; D000077194:Chlorophyll A
keywords: Alkaline phosphatase; DIP; DOP; Mediterranean Sea; Phosphorus; Plankton