The supramolecular architecture, function, and regulation of thylakoid membranes in red algae: an overview

Abstract

Red algae are a group of eukaryotic photosynthetic organisms. Phycobilisomes (PBSs), which are composed of various types of phycobiliproteins and linker polypeptides, are the main light-harvesting antennae in red algae, as in cyanobacteria. Two morphological types of PBSs, hemispherical- and hemidiscoidal-shaped, are found in different red algae species. PBSs harvest solar energy and efficiently transfer it to photosystem II (PS II) and finally to photosystem I (PS I). The PS I of red algae uses light-harvesting complex of PS I (LHC I) as a light-harvesting antennae, which is phylogenetically related to the LHC I found in higher plants. PBSs, PS II, and PS I are all distributed throughout the entire thylakoid membrane, a pattern that is different from the one found in higher plants. Photosynthesis processes, especially those of the light reactions, are carried out by the supramolecular complexes located in/on the thylakoid membranes. Here, the supramolecular architecture, function and regulation of thylakoid membranes in red algal are reviewed.

Effects of heavy metals and light levels on the biosynthesis of carotenoids and fatty acids in the macroalgae Gracilaria tenuistipitata (var. liui Zhang & Xia)

“…Fatty acids and carotenoids play an important role in the function and integrity of the chloroplast thylakoid membrane of photosynthetic organisms (Frank & Cogdell, 1996;Havaux, 1998;Sigaud-Kutner et al, 2002;Su et al, 2010). In fact, algal fatty acids (saturated, monounsaturated and polyunsaturated -PUFA) and carotenoids (carotenes and xanthophylls) vary their quality and quantity according to the environmental conditions (Barros et al, 2005;Britton, 1995;Cardozo et al, 2002;Collen et al, 2003;Colombo et al, 2006).…”

Phycobilisome composition in Chondrus crispus (Gigartinales, Rhodophyta) from a wild type strain and its vegetatively derived green mutant

“…The purple band isolated from the red Chondrus strain had similar amounts of PE and APC, giving a 0.753 ratio and almost 15 times as much PE to PC at 14.570 (Table 2). This ratio differed from that of the R-PE type I (3 peaks, 498, 540, and 565) (Su et al 2010b) with some absorption at approximately 620 nm and 650 nm, indicating the presence of PC and APC (Fig. 4).…”

“…The composition of red algal PBS typically consists of an APC core and several peripheral rods containing PC or PC/PE (Arteni et al 2008, Su et al 2010b. PE is the outermost pigment protein and its function is to increase the light harvesting capacity of the alga.…”

Determination of phycobiliproteins by constant-wavelength synchronous spectrofluorimetry method in red algae

“…From May through October, sun exposed plants contained less phycobilins compared to all other collection dates. R-PE and R-PC contents during the late fall to spring months (November-April) did not vary among sun exposures (Denis et al, 2010;Martinez & Rico, 2008;Sampath-Wiley et al, 2008;Su, Xie, Zang, Zhou, & Zhang, 2010;Xu & Gao, 2008;Zhang et al, 2011). On the other hand, in this work, we have analyzed dry algae.…”