Photosynthetic pigments in 37 species (65 strains) of Haptophyta: implications for oceanography and chemotaxonomy

Abstract

The pigment compositions of 37 species (65 strains) of cultured haptophytes were analysed using improved HPLC methods. We distinguished 8 pigment types based on the distribution of 9 chlorophyll c (chl c) pigments and 5 fucoxanthin derivatives. All types contained chl c 2 and Mg-2, 4-divinyl phaeoporphyrin a 5 monomethyl ester (MgDVP), fucoxanthin, diadinoxanthin and β,β-carotene. Pigment types were based on the following additional pigments: Type 1: chl c 1 ; Type 2: chl c 1 and chl c 2 -Pavlova gyrans-type; Type 3: chl c 1 and chl c 2 -monogalactosyl diacylglyceride ester (chl Type 5: Ochrosphaera spp.; Type 6: Nöelaerhabdaceae, notably Emiliania spp.; Type 7: Chrysochromulina spp.; Type 8: Phaeocystaceae, Prymnesiaceae and Isochrysidaceae. These pigment types showed a strong correlation with available phylogenetic trees, supporting a genetic basis for the pigment associations. The additional marker pigments offer oceanographers greater power for detecting haptophytes in mixed populations, while also distinguishing a greater proportion of them from diatoms. KEY WORDS: Haptophyta · HPLC · Chlorophylls c · Fucoxanthins · Pigment types · Phylogeny · Oceanography Resale or republication not permitted without written consent of the publisherMar Ecol Prog Ser 270: [83][84][85][86][87][88][89][90][91][92][93][94][95][96][97][98][99][100][101][102] 2004 1995, Heimdal 1997), it is so time-consuming that oceanographers routinely use photosynthetic pigment profiles as chemotaxonomic markers of phytoplankton groups . In order to interpret pigment data from field samples, however, a thorough knowledge of the pigment composition of each of the likely species groups of the phytoplankton populations is necessary. Unfortunately very few wide-ranging pigment surveys of algal classes have been published, exceptions being for diatoms (Stauber & Jeffrey 1988) and haptophytes (Jeffrey & Wright 1994). Dominant species in field samples should always be assessed microscopically in representative samples (Andersen et al. 1996, Wright & van den Enden 2000.Knowledge of pigment characteristics of any group is always limited by the resolution of current separation methods. The haptophyte pigment study of Jeffrey & Wright (1994), which used the SCOR-UNESCO HPLC method of Wright et al. (1991), distinguished most of the marker carotenoids, but failed to resolve monovinyl and divinyl analogues of chlorophyll c (e.g. chlorophylls c 1 and c 2 ) and additional fucoxanthin derivatives such as 4-keto-19'-hexanoyloxyfucoxanthin (Egeland et al. 2000). Nevertheless 4 useful pigment subgroups of the class were determined. New advances in HPLC pigment technology in the past decade (Jeffrey et al. 1999 [review], Zapata et al. 2000) have allowed a new examination of the pigment composition of this important group of microalgae in the present work.The recent methods of Garrido & Zapata (1997) and Zapata et al. (2000), in which polymeric C 18 or monomeric C 8 columns were used with pyridine as solvent modifier, have allowed separation of 11 ch...

Variability of phytoplankton pigment ratios across aquatic environments

“…Unfortunately, to date relatively few freshwater ecologists use pigment analysis with HPLC, so that studies on pigment ratios in pure cultures of freshwater algae have been relatively rare, hence few references are available for setting pigment ratio values. The intra-class variation observed in some marine planktonic algae (Zapata et al, 2004) is not as well constrained for freshwater algae (Nicklisch & Woitke, 1999). There is a clear need for additional studies on pigment composition in strains of freshwater algae from different groups, in order to develop a pigment ratio database, similar to that available for marine phytoplankton (Jeffrey et al, 1997), implemented by further analyses in particular groups presenting large chemotaxonomic diversity (Zapata et al, 2004).…”

“…Fewer studies have demonstrated intra-class variations of pigment composition and cell content (Nicklisch & Woitke, 1999;Zapata et al, 2004;Muylaert et al, 2006 and references therein), which are potentially a problem for the assessment of phytoplankton biomass based on pigments, but can also help increase the discriminative power of the pigment method. The recent study by Schlu¨ter et al (2006), however, represents significant progress in defining adequate pigment ratios for the main freshwater phytoplankton classes by taking into account the light conditions.…”

Microzooplankton grazing and phytoplankton growth in marine mesocosms with increased CO<sub>2</sub> levels

“…A clear 19 -hexanoyloxyfucoxanthin-like peak was found in the samples. This peak was regarded as being typical for prymnesiophytes or even specific for coccolithophorids (Zapata et al, 2004). It corresponded to 4-keto-19 -hexanoyloxyfucoxanthin (4-keto-hex), recently reported by Airs and Llewellyn (Airs and Llewellyn, 2006).…”

Phytoplankton community structure in the river‑influenced continental margin of the northern Gulf of Mexico

“…Initial ratios of phytoplankton groups at midshelf represented a combination of both inner shelf and slope water values. The haptophyte phytoplankton group was subdivided into haptophyte-6 (hapto-6) and haptophyte-8 (hapto-8) according to Zapata et al (2004), and prasinophytes were divided into prasinophyte-I (pras-I) and prasinophyte-II (pras-II) after Schlüter et al (2006). Optimization of the input pigment:chl a ratio matrix was achieved through the construction of a series of 60 different ratio matrices by multiplying each ratio of the initial matrix by a random function as described in Roy et al (2011).…”