Chlorophyll c(2) monogalactosyldiacylglyceride ester (chl c(2)-MGDG). A novel marker pigment for Chrysochromulina species (Haptophyta)

The pigment composition of the haptophyte Chrysochromulina polylepis (Strai n CCMP 286) was analysed by high-performance liquid chromatography (HPLC) u sing pyridine-containing mobile phases and polymeric C-18, or monomeric C-8 columns. The polar chlorophyll (chl) c pigment composition included chl c( 2) and chl c(3) as major fractions, and divinyl protochlorophyllide a (DV p chlide or MgDVP) as a minor component, Several non-polar fluorescent peaks sharing a common chl c-type absorption spectrum were also detected. The mai n component of these peaks was isolated and characterised by chromatographi c behaviour, UV-visible (UV-VIS) and fluorescence spectroscopy, Although sp ectral properties were similar to a high molecular weight non-polar chl c ( 1313 Da) recently characterised from Emiliania huxleyi, both chlorophylls s howed different chromatographic behaviour. Fast atom bombardment-mass spect rometry (FAB-MS) analysis showed a high mass molecular ion (m/z 1265), and a fragmentation pattern compatible with a molecular structure consisting of a chl c2 pigment linked by an ester bond to the sugar moiety of a monogala ctosyl. diacylglyceride (MGDG), which included 2 myristic acid (14:0) resid ues. To study the distribution pattern of the novel pigment, different stra ins of C, polylepis and other species of the genus Chrysochromulina were an alysed, A similar chl c2 ester was also present in 2 C. polylepis strains ( K, B11) and in C, aff. polylepis (PLY 200), as well as in C. acantha, C. ca mella, C, leadbeateri, C. strobilus, C. throndsenii, and Chrysochromulina s p. (CS-410). Three species, C. fragaria, C. hirta (2 strains) and C. kappa, lacked the new chl c, but they contained detectable amounts of other nonpo lar chl c-like pigments. The feasibility of using chls c and carotenoids as marker pigments to detect Chrysochromulina species in field samples is dis cussed.