Page 34 - Algae

General Overview 17

TABLE 1.4
The Main Pigments, Storage Products, and Cell Coverings of the Algal Divisions

Pigments
Division Chlorophylls Phycobilins Carotenoids Xanthophylls Storage Products

Cyanophyta a c-Phycoerythrin b-Carotene Myxoxanthin Cyanophycin
c-Phycocyanin Zeaxanthin (argine and
Allophycocyanin asparagine
Phycoerythrocyanin polymer)
Cyanophycean
starch
(a-1,4-glucan)
Prochlorophyta a, b Absent b-Carotene Zeaxanthin Cyanophycean
starch (a-1,
4-glucan)
Glaucophyta a c-Phycocyanin b-Carotene Zeaxanthin Starch
Allophycocyanin (a-1,4-glucan)
Rhodophyta a r,b-Phycoerythrin a- and Lutein Floridean starch
r-Phycocyanin b-Carotene (a-1,4-glucan)
Allophycocyanin
Cryptophyta a, c Phycoerythrin-545 a-, b-, and Alloxanthin Starch
r-Phycocyanin 1-Carotene (a-1,4-glucan)
Heterokontophyta a, c Absent a-, b-, and Fucoxanthin, Chrysolaminaran
1-Carotene Violaxanthin (b-1,3-glucan)
Haptophyta a, c Absent a- and b-Carotene Fucoxanthin Chrysolaminaran
(b-1,3-glucan)
Dinophyta a, b, c Absent b-Carotene Peridinin, Starch
Fucoxanthin, (a-1,4-glucan)
Diadinoxanthin
Dinoxanthin
Gyroxanthin
Euglenophyta a, b Absent b- and Diadinoxanthin Paramylon
g-Carotene (b-1,3-glucan)
Chlorarachniophyta a, b Absent Absent Lutein, Paramylon
Neoxanthin, (b-1,3-glucan)
Violaxanthin
Chlorophyta a, b Absent a-, b-, and Lutein Starch
g-Carotene Prasinoxanthin (a-1,4-glucan)

and equidistant, in contrast to prochlorophytes and most other algae, but similar to Rhodopyta and
Glaucophyta.
The reserve polysaccharide is cyanophycean starch, stored in tiny granules lying between the
thylakoids. In addition, these cells often contain cyanophycin granules, that is, polymer of arginine
and asparagine. Some marine species also contain gas vesicles used for buoyancy regulation. In
some filamentous cyanobacteria, heterocysts and akinetes are formed. Heterocysts are vegetative
cells that have been drastically altered (loss of photosystem II, development of a thick, glycolipid
cell wall) to provide the necessary anoxygenic environment for the process of nitrogen fixation
(Figure 1.27). Some cyanobacteria produce potent hepato- and neurotoxins.
Prochlorophytes can be unicellular or filamentous, and depending on the filamentous species,
they can be either branched or unbranched. They exist as free-living components of pelagic