Carotenoids with conjugated carbonyl groups possess special photophysical properties which have been studied in some water-soluble light-harvesting proteins [1].However,siphonaxanthin type light-harvesting complexes of photosystem Ⅱ (LHCII) in siphonous green alga have received fewer studies.In the present study,we determined sequences of genes for several Bryopsis corticulans Lhcbm proteins,which showed that they belong to the group of major LHCII and diverged early from green algae and higher plants.