Flagellar membrane proteins of Tetraselmis striata butcher (Chlorophyta)

Highly purified flagella of the green alga Tetraselmis striata (Chlorophyta ) were extracted by Triton X-114 phase partitioning. SDS-PAGE analysis reve aled that most proteins were present in the aqueous phase, only two promine nt flagellar membrane proteins (fmp) of apparent molecular weight 145 and 5 7 kDa (fmp145 and fmp57) were enriched: in the detergent phase. Fmp145 was purified by gel permeation chromatography. Glycosidase treatment in combina tion with lectin blot analysis showed that fmp145 is a glycoprotein contain ing 3-5 N-glycans of the high mannose and/or hybrid type. A polyclonal anti body (anti-fmp136) was raised against the deglycosylated form of fmp145 and used to localize fmp145 by immunofluorescence and immunoelectron microscop y. Immunogold labeling showed fmp145 to be present between the scale layers and the flagellar membrane. During flagellar regeneration fmp145 is incorp orated evenly and rapidly into the newly developing flagella. Anti-fmp136 s pecifically cross-reacted with flagella of only a subgroup of Tetraselmis s trains characterized by a specific flagellar hair type (type II according t o Marin et al. 1993) and thus could be a useful immunomarker for the identi fication of Tetraselmis strains by fluorescence microscopy.