Complete Sequence and Analysis of Plastid Genomes of Two Economically Important Red Algae: Pyropia haitanensis and Pyropia yezoensis

An increase in seawater temperature owing to global warming is expected to substantially limit the growth of marine algae, including Pyropia yezoensis, a commercially valuable red alga. To improve our knowledge of the genes involved in the acquisition of heat tolerance in P. yezoensis, transcriptomes sequences were obtained from both the wild-type SG104 P. yezoensis and heat-tolerant mutant Gy500. We selected 1,251 differentially expressed genes that were up- or downregulated in response to the heat stress condition and in the heat-tolerant mutant Gy500, based on fragment per million reads expression values. Among them, PyHRG1 was downregulated under heat stress in SG104 and expressed at a low level in Gy500. PyHRG1 encodes a secretory protein of 26.5 kDa. PyHRG1 shows no significant sequence homology with any known genes deposited in public databases to date. However, PyHRG1 homologs were found in other red algae, including other Pyropia species. When PyHRG1 was introduced into the single-cell green alga Chlamydomonas reinhardtii, transformed cells overexpressing PyHRG1 showed severely retarded growth. These results demonstrate that PyHRG1 encodes a novel red algae-specific protein and plays a role in heat tolerance in algae. The transcriptome sequences obtained in this study, which include PyHRG1, will facilitate future studies to understand the molecular mechanisms involved in heat tolerance in red algae.

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Hypothesis: Gene-rich plastid genomes in red algae may be an outcome of nuclear genome reduction

Journal of Phycology ◽

10.1111/jpy.12514 ◽

2017 ◽

Vol 53 (3) ◽

pp. 715-719 ◽

Cited By ~ 8

Author(s):

Huan Qiu ◽

Jun Mo Lee ◽

Hwan Su Yoon ◽

Debashish Bhattacharya

Keyword(s):

Red Algae ◽

Nuclear Genome ◽

Genome Reduction ◽

Plastid Genomes

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Mitochondrial and Plastid Genomes from Coralline Red Algae Provide Insights into the Incongruent Evolutionary Histories of Organelles

Genome Biology and Evolution ◽

10.1093/gbe/evy222 ◽

2018 ◽

Vol 10 (11) ◽

pp. 2961-2972 ◽

Cited By ~ 11

Author(s):

Jun Mo Lee ◽

Hae Jung Song ◽

Seung In Park ◽

Yu Min Lee ◽

So Young Jeong ◽

...

Keyword(s):

Red Algae ◽

Coralline Red Algae ◽

Plastid Genomes

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Complete sequence and analysis of plastid genomes of Pseudo-nitzschia multiseries (Bacillariophyta)

Mitochondrial DNA Part A ◽

10.3109/19401736.2015.1060428 ◽

2015 ◽

Vol 27 (4) ◽

pp. 2897-2898 ◽

Cited By ~ 5

Author(s):

Min Cao ◽

Xiao-Long Yuan ◽

Guiqi Bi

Keyword(s):

Complete Sequence ◽

Plastid Genomes

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Characterization of the heterooligomeric red-type rubisco activase from red algae

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1610758113 ◽

2016 ◽

Vol 113 (49) ◽

pp. 14019-14024 ◽

Cited By ~ 23

Author(s):

Nitin Loganathan ◽

Yi-Chin Candace Tsai ◽

Oliver Mueller-Cajar

Keyword(s):

Red Algae ◽

Atp Hydrolysis ◽

Mutational Analysis ◽

Higher Plants ◽

Cyanidioschyzon Merolae ◽

Kinetic Properties ◽

Bisphosphate Carboxylase ◽

Plastid Genomes ◽

Eukaryotic Phytoplankton ◽

Red Algal

The photosynthetic CO2-fixing enzyme ribulose 1,5-bisphosphate carboxylase/oxygenase (rubisco) is inhibited by nonproductive binding of its substrate ribulose-1,5-bisphosphate (RuBP) and other sugar phosphates. Reactivation requires ATP-hydrolysis–powered remodeling of the inhibited complexes by diverse molecular chaperones known as rubisco activases (Rcas). Eukaryotic phytoplankton of the red plastid lineage contain so-called red-type rubiscos, some of which have been shown to possess superior kinetic properties to green-type rubiscos found in higher plants. These organisms are known to encode multiple homologs of CbbX, the α-proteobacterial red-type activase. Here we show that the gene products of two cbbX genes encoded by the nuclear and plastid genomes of the red algae Cyanidioschyzon merolae are nonfunctional in isolation, but together form a thermostable heterooligomeric Rca that can use both α-proteobacterial and red algal-inhibited rubisco complexes as a substrate. The mechanism of rubisco activation appears conserved between the bacterial and the algal systems and involves threading of the rubisco large subunit C terminus. Whereas binding of the allosteric regulator RuBP induces oligomeric transitions to the bacterial activase, it merely enhances the kinetics of ATP hydrolysis in the algal enzyme. Mutational analysis of nuclear and plastid isoforms demonstrates strong coordination between the subunits and implicates the nuclear-encoded subunit as being functionally dominant. The plastid-encoded subunit may be catalytically inert. Efforts to enhance crop photosynthesis by transplanting red algal rubiscos with enhanced kinetics will need to take into account the requirement for a compatible Rca.

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Extraction and Purification of R-Phycoerythrin Alpha Subunit from the Marine Red Algae Pyropia Yezoensis and Its Biological Activities

Molecules ◽

10.3390/molecules26216479 ◽

2021 ◽

Vol 26 (21) ◽

pp. 6479

Author(s):

Selvakumari Ulagesan ◽

Taek-Jeong Nam ◽

Youn-Hee Choi

Keyword(s):

Antioxidant Activity ◽

Fluorescence Spectroscopy ◽

Red Algae ◽

Biological Activities ◽

Sequence Similarity ◽

Pyropia Yezoensis ◽

Alpha Subunit ◽

Ammonium Sulfate Precipitation ◽

Extraction And Purification ◽

Uv Visible

Phycoerythrin is a major light-harvesting pigment of red algae and cyanobacteria that is widely used as a fluorescent probe or as a colorant in the food and cosmetic industries. In this study, phycoerythrin was extracted from the red algae Pyropia yezoensis and purified by ammonium sulfate precipitation and various chromatography methods. The purified phycoerythrin was analyzed by UV-visible and fluorescence spectroscopy. The isolated pigment had the typical spectrum of R-phycoerythrin, with a trimmer state with absorbance maxima at 497, 536, and 565 nm. It was further purified and identified by LC-MS/MS and Mascot search. It showed a 100% sequence similarity with the R-phycoerythrin alpha subunit of Pyropia yezoensis. The molecular mass was 17.97 kDa. The antioxidant activity of the purified R-phycoerythrin alpha subunit was analyzed. It showed significant antioxidant activity in ABTS and FRAP assays and had significant cytotoxicity against HepG2 cells.

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Functional Characterization and Evolutionary Analysis of Glycine-Betaine Biosynthesis Pathway in Red Seaweed Pyropia yezoensis

Marine Drugs ◽

10.3390/md17010070 ◽

2019 ◽

Vol 17 (1) ◽

pp. 70 ◽

Cited By ~ 4

Author(s):

Yunxiang Mao ◽

Nianci Chen ◽

Min Cao ◽

Rui Chen ◽

Xiaowei Guan ◽

...

Keyword(s):

Red Algae ◽

Glycine Betaine ◽

Abiotic Stresses ◽

Pyropia Yezoensis ◽

Early Gene ◽

Gene Copy ◽

Betaine Aldehyde Dehydrogenase ◽

Evolutionary Analysis ◽

Red Seaweed ◽

Biosynthesis Pathway

The red seaweed Pyropia yezoensis is an ideal research model for dissecting the molecular mechanisms underlying its robust acclimation to abiotic stresses in intertidal zones. Glycine betaine (GB) was an important osmolyte in maintaining osmotic balance and stabilizing the quaternary structure of complex proteins under abiotic stresses (drought, salinity, etc.) in plants, animals, and bacteria. However, the existence and possible functions of GB in Pyropia remain elusive. In this study, we observed the rapid accumulation of GB in desiccated Pyropia blades, identifying its essential roles in protecting Pyropia cells against severe osmotic stress. Based on the available genomic and transcriptomic information of Pyropia, we computationally identified genes encoding the three key enzymes in the GB biosynthesis pathway: phosphoethanolamine N-methyltransferase (PEAMT), choline dehydrogenase (CDH), and betaine aldehyde dehydrogenase (BADH). Pyropia had an extraordinarily expanded gene copy number of CDH (up to seven) compared to other red algae. Phylogeny analysis revealed that in addition to the one conservative CDH in red algae, the other six might have originated from early gene duplication events. In dehydration stress, multiple CDH paralogs and PEAMT genes were coordinating up-regulated and shunted metabolic flux into GB biosynthesis. An elaborate molecular mechanism might be involved in the transcriptional regulation of these genes.

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