Demonstration of a true phenoloxidase activity and activation of a ProPO cascade in Pacific oyster, Crassostrea gigas (Thunberg) in vitro

Type Article
Date 2007-04
Language English
Author(s) Hellio Claire1, Bado Nilles Anne2, Gagnaire Beatrice3, Renault Tristan3, Thomas-Guyon Helene2
Affiliation(s) 1 : Univ La Rochelle, Ctr Rech Ecosyst Littoraux Anthropises, UMR6217, CBRS IFREMER, F-17042 La Rochelle 01, France.
2 : Univ Portsmouth, Sch Biol Sci, Portsmouth PO1 2DY, Hants, England.
3 : IFREMER, LGP, F-17390 La Tremblade, France.
Source Fish & Shellfish Immunology (1050-4648) (Elsevier), 2007-04 , Vol. 22 , N. 4 , P. 433-440
DOI 10.1016/j.fsi.2006.06.014
WOS© Times Cited 83
Keyword(s) Prophenoloxidase, Phenoloxidase, Oyster, Immunity, Defence, Crassostrea gigas
Abstract The prophenoloxidase (ProPO) system is the origin of melanin production and is considered to be an innate defence mechanism in invertebrates. In different bivalve species, phenoloxidase (PO) is present in the haemolymph as an inactive form of ProPO. The present study focuses on the Pacific adult oyster, Crassostrea gigas, an economically important bivalve species along French coasts. The results indicate that many factors may inhibit the PO-like activity. These include: phenylthiourea (PTU), sodium diethylthiocarbamate (DETC), beta-mercaptoethanol and tropolone, which repressed the spontaneous PO activity. The activation of PO-like activity in C. gigas acellular fraction by lipopolysaccharide (LPS) involved participation of other factors, including at least one serine protease. PO was present as proPO in the acellular fraction of haemolymph and haemocytes of C. gigas and could be activated by an exogenous protease (trypsin-N-tosyl-L-phenylalanine chloromethyl ketone) when used at 1 g L-1. Treatment of acellular fractions with other modulators/activators namely LPS (1 g L-1), zymosan (0.6 g L-1) or laminarin (0.6 g L-1) also increased PO-like activity but to a less important way. The study demonstrated the evidence of a true phenoloxidase activity in Pacific oyster, C. gigas (Thunberg). The activation of a proPO system by non-self molecules suggests the role played by PO in vivo in the internal defence mechanisms. Understanding the activation of the ProPO system could enable the evaluation of the health of oyster stocks. (c) 2006 Published by Elsevier Ltd.
Full Text
File Pages Size Access
publication-2926.pdf 10 93 KB Open access
Top of the page

How to cite 

Hellio Claire, Bado Nilles Anne, Gagnaire Beatrice, Renault Tristan, Thomas-Guyon Helene (2007). Demonstration of a true phenoloxidase activity and activation of a ProPO cascade in Pacific oyster, Crassostrea gigas (Thunberg) in vitro. Fish & Shellfish Immunology, 22(4), 433-440. Publisher's official version : , Open Access version :