Article
Multidisciplinary Sciences
Helena M. van Tol, E. Virginia Armbrust
Summary: Diatoms are unicellular photosynthetic algae that secrete organic matter to fuel secondary production in the ocean. Research shows that diatoms secrete different organic nitrogen and sulfur compounds by balancing redox reactions through nitrate or sulfate uptake, which has significant implications for bacteria in the surface ocean.
Article
Plant Sciences
Lu Zhou, Shan Gao, Wenting Yang, Songcui Wu, Li Huan, Xiujun Xie, Xulei Wang, Senjie Lin, Guangce Wang
Summary: Diatoms express multiple genes under fluctuating light conditions in order to adapt to changing light environments. Prolonged preconditioning in severe light fluctuations enhances photosynthesis and carbon metabolism in diatoms, promoting their growth.
Article
Marine & Freshwater Biology
Xiao-Huang Chen, Ming-Kun Yang, Yuan-Yuan Li, Zhang-Xian Xie, Shu-Feng Zhang, Mats Topel, Shady A. A. Amin, Lin Lin, Feng Ge, Da-Zhi Wang
Summary: Diatoms are crucial for global carbon cycling and climate as they are responsible for 20% of global carbon fixation and 40% of marine primary productivity. Although ten diatom genome sequences are available, there is still a lack of comprehensive diatom proteome data. In this study, a proteome map of the model marine diatom Thalassiosira pseudonana was constructed using high-resolution mass spectrometry and proteogenomic strategy, identifying 9526 proteins and improving the genome annotation. The proteome catalog will complement existing diatom genome and transcriptome data for further biological and ecological research.
MARINE LIFE SCIENCE & TECHNOLOGY
(2023)
Article
Plant Sciences
Zhengke Li, Yong Zhang, Wei Li, Andrew J. Irwin, Zoe V. Finkel
Summary: Marine planktonic diatoms, including Thalassiosira pseudonana, play a vital role in phytoplankton blooms and marine primary production due to their ability to respond quickly to environmental changes. Through RNA-Seq analysis, this study identified a subset of 1076 genes termed the diatom environmental stress response (d-ESR) that are differentially expressed in response to various stressors affecting energy balance and metabolic capacity. It was found that the d-ESR mainly consists of genes involved in maintaining proteome homeostasis and primary metabolism. Additionally, the study revealed the regulation of photosynthesis and the unique role of chloroplast in managing environmental stress in diatoms.
Article
Microbiology
Dong Xu, Shujie Huang, Xiao Fan, Xiaowen Zhang, Yitao Wang, Wei Wang, John Beardall, Georgina Brennan, Naihao Ye
Summary: Projected ocean acidification (OA) alters seawater chemistry and bio-toxicity of metal ions, but its effect on marine microalgae resilience to metal stress is unclear. This study examines the impact of OA on copper metabolism in Thalassiosira pseudonana. Results show that increased pCO(2) promotes growth and photosynthesis, but decreases copper accumulation and toxicity. The study also reveals alterations in copper detoxification strategies and enhanced antioxidant enzyme activities under elevated CO2. These findings provide insight into the bioremediation capacity of marine primary producers under climate change.
FRONTIERS IN MICROBIOLOGY
(2023)
Article
Plant Sciences
Zhengke Li, Wei Li, Yong Zhang, Yingyu Hu, Rosie Sheward, Andrew J. Irwin, Zoe V. Finkel
Summary: Stressful environmental conditions induce various acclimation mechanisms in marine phytoplankton, leading to changes in their photophysiology. Changes in temperature, irradiance, and ROS often result in rapid photophysiological responses (<2 h), while nutrient starvation leads to slower but larger effects (6-72 h). This study aims to facilitate the interpretation of fluorescence data to enhance our understanding of phytoplankton photophysiology.
JOURNAL OF PHYCOLOGY
(2021)
Article
Biotechnology & Applied Microbiology
Karthick Murugan Palanisamy, Gaanty Pragas Maniam, Ahmad Ziad Sulaiman, Mohd Hasbi Ab Rahim, Natanamurugaraj Govindan, Yusuf Chisti
Summary: Biomass and lipid production of Thalassiosira pseudonana, a marine centric diatom, were studied using palm oil mill effluent (POME) as a nutrient source. The optimal medium consisted of 20% POME, 80 μM Na2SiO3, and 35 g NaCl L-1, with a pH of approximately 7.7. Under specific light conditions, high biomass and lipid content were achieved in Thalassiosira pseudonana cultures.
FERMENTATION-BASEL
(2022)
Article
Microbiology
Bokun Chen, Jihua Liu, Ge Xu, Gang Li
Summary: This study investigates the effects of oxygen levels and light:dark cycles on the growth, cell composition, photosynthesis, and transcriptome of the diatom Thalassiosira pseudonana. The results show that the impact of low oxygen concentration on diatom growth is determined by the oxygen level and is influenced by the photoperiod. Additionally, various cellular processes such as photosynthesis, respiration, and metabolism are affected by oxygen availability and light conditions, with differential gene expression patterns observed under different oxygen levels and light:dark cycles.
Article
Plant Sciences
Alastair W. Skeffington, Marc Gentzel, Andre Ohara, Alexander Milentyev, Christoph Heintze, Lorenz Boettcher, Stefan Goerlich, Andrej Shevchenko, Nicole Poulsen, Nils Kroeger
Summary: This study extracted silica proteins from three diatom species and found that there were no common proteins among them, and most proteins showed low similarity in sequence alignments. Bioinformatic analysis grouped these proteins into different classes based on unconventional sequence motifs, but their functions are still unclear. In vivo localization results of selected proteins suggest that proteins lacking sequence homology but sharing unconventional sequence motifs may have similar functions in diatom silica cell wall morphogenesis.
Article
Plant Sciences
Zhengke Li, Yong Zhang, Wei Li, Andrew J. Irwin, Zoe Finkel
Summary: Housekeeping genes show variations across different organisms, and their characteristics are influenced by various selection pressures, making them unlikely to have universal fundamental roles in cellular maintenance.
Article
Biotechnology & Applied Microbiology
Yan Liu, Yixuan Li, Hejing Zhao, Bilu Zhu, Jilin Xu, Feng Xu, Shixia Liu, Xiaohui Li, Chengxu Zhou
Summary: This study demonstrates that phloroglucinol, a growth promoter in higher plants, can also increase growth and fucoxanthin synthesis in the microalga Thalassiosira pseudonana, indicating its potential application in industrial fucoxanthin production. The treatment of phloroglucinol induces the synthesis of cis-zeatin and brassinolide in T. pseudonana, and the signaling pathways of cis-zeatin and brassinolide are involved in the phloroglucinol-driven increases in growth and fucoxanthin synthesis. Therefore, this work elucidates the molecular mechanism by which phloroglucinol promotes growth and fucoxanthin synthesis in T. pseudonana and suggests that cis-zeatin and brassinolide, along with phloroglucinol, have the potential to be used as inducers of increased microalgal fucoxanthin production.
APPLIED AND ENVIRONMENTAL MICROBIOLOGY
(2022)
Article
Biotechnology & Applied Microbiology
Nerissa L. Fisher, Kimberly H. Halsey, David J. Suggett, Michelle Pombrol, Peter J. Ralph, Adrian Lutz, E. Maggie Sogin, Jean-Baptiste Raina, Jennifer L. Matthews
Summary: This study used transcriptomic and metabolomic approaches to study the mechanisms underlying diatom acclimation and growth under different light intensities. The results showed that diatoms shift their carbon and energy fluxes depending on the growth rate driven by light. Under high light conditions, diatoms upregulate metabolic pathways for fatty acid, glycolic acid, and carbohydrate production to support fast growth. Under low light conditions, diatoms conserve energy through upregulation of carbon retention pathways and regulate metabolites associated with light harvesting, energy storage, and signaling. These findings provide important insights for predicting and manipulating diatom growth and bio-production.
ALGAL RESEARCH-BIOMASS BIOFUELS AND BIOPRODUCTS
(2023)
Article
Biotechnology & Applied Microbiology
Gina V. Filloramo, Bruce A. Curtis, Emma Blanche, John M. Archibald
Summary: The marine diatoms Thalassiosira pseudonana and Phaeodactylum tricornutum are valuable model organisms for exploring the evolution, diversity, and ecology of the algal group. Long-read sequencing technology was used to update and validate the quality and contiguity of their genomes, leading to the resolution of uncertain genomic regions and identification of novel genes. Despite the challenges posed by repetitive DNA sequences, the revised reference genomes provide additional insight into the structure and evolution of these genomes for future diatom research.
Article
Plant Sciences
Nigel Belshaw, Irina Grouneva, Lior Aram, Assaf Gal, Amanda Hopes, Thomas Mock
Summary: CRISPR/Cas technology enables efficient gene targeting by homologous recombination in the diploid photosynthetic organism Thalassiosira pseudonana. Knockout of nitrate reductase and urease genes affected growth on nitrate and urea, respectively, while knockout of the silacidin gene led to a significant increase in cell size.
Article
Plant Sciences
Anxhela Hania, Meri Eichner, Alessandra Norici, Ondrej Prasil, Mario Giordano
Summary: Temperature is a key environmental factor affecting the life of microalgae, with cells exhibiting either acclimation or homoeostatic responses depending on growth rates. Different diatom species demonstrate species-specific compositional responses to varying temperature, highlighting the diversity in ecophysiological strategies of diatoms and the importance of considering these differences when predicting climate change responses.
Article
Biotechnology & Applied Microbiology
Sung-Yeoul Kim, Vikash Chandra Roy, Jin-Seok Park, Byung-Soo Chun
Summary: This study aims to extract functional substances from Undaria pinnatiida sporophyll using supercritical carbon dioxide (SC-CO2) and subcritical water extraction (SWE). The results showed that the consecutive green extraction method can yield extracts rich in fucoxanthin and beta-carotene, and the sporophyll of Undaria pinnatiida contains health-beneficial fatty acids. Additionally, SWE can extract substances with antioxidant, antibacterial, and antihypertensive activities.
ALGAL RESEARCH-BIOMASS BIOFUELS AND BIOPRODUCTS
(2024)