Open AccessStudy of the conversion of GDP‐mannose into GDP‐fucose in Nereids: a biochemical marker of oocyte maturation
Author(s) -
BULET Philippe,
HOFLACK Bernard,
PORCHET Maurice,
VERBERT André
Publication year - 1984
Publication title -
european journal of biochemistry
Language(s) - English
Resource type - Journals
eISSN - 1432-1033
pISSN - 0014-2956
DOI - 10.1111/j.1432-1033.1984.tb08458.x
Subject(s) - mannose , fucose , chemistry , oocyte , biochemistry , galactose , enzyme , biology , microbiology and biotechnology , embryo
Homogenates of Perinereis cultrifera oocytes were found to transform GDP‐ d ‐mannose into another sugar nucleotide. Ultraviolet absorption spectra, chromatographic behaviour, gas‐liquid chromatography coupled to mass spectrometry analysis revealed that GDP‐ d ‐mannose had been converted into GDP‐ l ‐fucose. This conversion is a multi‐step reaction as proved by the involvement of two intermediates identified as GDP‐4‐oxo‐6‐deoxy‐ d ‐mannose and GDP‐4‐oxo‐6‐deoxy‐ l ‐galactose, this latter being reduced by NADPH to give GDP‐ l ‐fucose. It is shown that the enzymatic activities responsible for the conversion of GDP‐ d ‐mannose into GDP‐ l ‐fucose is recovered only in oocytes and is not present in the other coelomic cells (i.e. coelomocytes). More interesting is the fact that maximum‐activity is recovered at a well defined stage of the hormone‐controlled oogenesis. Thus, this enzymatic system appears as a biochemical marker of the oocyte maturation in P. cultrifera.