Diatom Photosynthesis: From Primary Production to High-Value Molecules

This comprehensive guide is designed for researchers, professionals, and students looking to deepen their knowledge of diatoms, including detailed information on diatom photosynthesis regulation at the molecular scale, as well as their significant ecological roles, all aimed at promoting sustainable advancements and the safeguarding of aquatic ecosystems. Diatoms exert an immense influence on the ecosystem of Earth due to their remarkable abundance and species diversity. Thriving in diverse habitats spanning the oceans, intertidal benthic zones, saline and freshwater environments, and even terrestrial niches like moist soil, forests, and caves, they play an integral role. Diatoms alone account for around 20% of the oxygen generated by photosynthesis, comparable to the combined productivity of tropical rainforests worldwide, while their primary production can reach 40–45% in marine ecosystems. Nevertheless, in contrast to the extensive research on macroscopic photosynthetic organisms, investigations in this domain remain comparatively limited, despite the role of diatoms in global biogeochemical processes. This book presents an exhaustive review of the subject matter, encompassing a wide spectrum of topics ranging from the intricate molecular mechanisms of diatom photosynthesis and light absorption to the dominant role of diatoms as primary producers within ecological frameworks. Beyond this, the book delves into the practical implications stemming from diatoms and their photosynthetic productivity. A strong emphasis is placed on the importance of fundamental research in deepening our understanding of the natural world around us. Diatoms Photosynthesis provides readers with a comprehensive guide to understanding the fundamentals of diatom photosynthesis and their ecological significance in aquatic ecosystems; a guide to the potential of diatom-derived products for sustainable technologies; a roadmap from diatom photosynthesis to implications in applied sciences; a bridge to span the gap between fundamental research on diatoms and their practical applications. Audience This book caters to academic professionals, students, and researchers in the fields of marine biology, ecology, microbiology, and biochemistry. It offers insights and benefits into diatom photosynthesis, diatom physiology, biodiversity, ecosystem health, and sustainable technological advancements.

Table of Contents:
Preface xxvii Acknowledgements xxix Part 1: Evolution and Genetics 1 1 Comparing Diatom Photosynthesis with the Green Lineage: Electron Transport, Carbon Fixation and Metabolism 3 Dany Croteau, Erik Jensen, Christian Wilhelm and Benjamin Bailleul 1.1 Introduction 5 1.2 Conservation and Diversity within Oxygenic Photosynthesis 6 1.3 Consequences of the Secondary Endosymbiosis and Thylakoid Ultrastructure 9 1.4 Different Modes of Photosynthetic Electron Flows 12 1.5 Regulation of CO2 Concentration, CO2 Fixation and Carbon Metabolism 18 1.6 General Response of Photosynthesis to Environmental Stresses 22 1.7 Conclusion 25 2 Genetic Regulation of Diatom Photosynthesis: Understanding and Exploiting Genetic Diversity 45 Charlotte Volpe, Marianne Nymark and Tore Brembu 2.1 Regulation of Photosynthesis 47 2.2 Diatom Genomes 48 2.3 Photosynthetic Components in Diatom Genomes 50 2.4 Responses to Changes in Light Intensity 54 2.5 Circadian Rhythmicity 57 2.6 Responses to Changes in Light Quality 58 2.7 Retrograde Signaling 59 2.8 Gene Editing for Functional Characterization and Commercial Applications 61 2.9 Conclusion 68 3 Evolution of Plastids and Mitochondria in Diatoms 81 Ansgar Gruber and Miroslav Oborník 3.1 Introduction 81 3.2 Origin and Evolution of Diatom Plastids 83 3.3 Derived States of Diatom Plastids 94 3.4 Consequences of Complex Plastid Acquisition 96 3.5 Conclusions and Outlook 100 4 Structure and Dynamics of the Diatom Chloroplast 113 Monika Bojko, Stanislaw Listwan, Reimund Goss and Dariusz Latowski 4.1 Evolution and Structure of Diatom Chloroplasts 114 4.2 Architecture of the Diatom Thylakoid Membrane 118 4.3 Molecular Dynamics and Structure of the Diatom Thylakoid Membrane Under Different Light Conditions 125 4.4 Molecular Dynamics and Structure of the Diatom Thylakoid Membrane Under Different Thermal Conditions 127 4.5 Conclusion 128 Part 2: Interaction with Light 137 5 Pigments in Diatoms: Light Absorption and Beyond 139 Paulina Kuczyñska, Ma³gorzata Jemio³a-Rzemiñska and Kazimierz Strza³ka 5.1 Environmental Factors Affect Pigments in Diatoms 139 5.2 Diatoms are Well Adapted to Changing Light Conditions 141 5.3 Photosynthetic Pigments in Diatoms are Chlorophylls and Carotenoids 143 5.4 The Main Pigment in Diatoms – Chlorophyll a Plays a Central Role in Photochemical Energy Conversion 148 5.5 Chlorophyll c Participates in Photosynthesis as an Accessory Pigment 150  5.6 Fucoxanthin-Binding Proteins in Diatoms Play a Special Role 151 5.7 Regulation of Protochlorophyllide Oxidoreductases was Examined in Diatoms but Further Steps of Chlorophyll c Biosynthesis Remain Unclear 152 5.8 Fucoxanthin is the Main Light-Harvesting Carotenoid in Diatom 155 5.9 High Bioavailability and Bioactivity of Fucoxanthin Makes It a Desirable Compound Obtained by Extraction 158 5.10 Beneficial Effects of Fucoxanthin are Versatile 160 5.11 Diadinoxanthin and Diatoxanthin are Involved in Cyclic Changes, Ensuring Photoprotection 161 5.12 Diatoms Also Possess the Violaxanthin Cycle, but It is not the First Line of Defense Against Excessive Light Energy 163 5.13 Mechanisms of NPQ in Diatoms are Complex and Differ Depending on Species 163 5.14 Many Carotenogenic Enzymes and Genes in Diatoms Have not yet Been Revealed 165 5.15 Analysis and Production of Diatom Pigments are Challenging Tasks with Promising Prospects 167 5.16 Conclusions 170 6 Function, Structure and Organization of Light-Harvesting Proteins in Diatoms 191 Charlotte Volpe and Claudia Büchel 6.1 Introduction 192 6.2 The FCP Proteins 194 6.3 Structure, Pigmentation and Energy Transfer 195 6.4 Macroorganization of FCP-PSI/II Supercomplexes 198 6.5 Role of the Chloroplast Signal Recognition Particle Pathway (CpSRP) 201 6.6 Balancing Light Absorption and Photoprotection 202 6.7 Conclusion 206 7 Sensing Light Underwater: An Update on Photoreceptors in Diatoms 217 Manuel Serif and Per Winge 7.1 Introduction 219 7.2 Rhodopsins 221 7.3 Phytochromes 223 7.4 Cryptochrome/Photolyase Family 226 7.5 Aureochromes 231 7.6 Conclusion 235 8 Non-Invasive Biophysical Techniques to Monitor the Structural Plasticity of the Photosynthetic Machinery of Live Diatom Cells 245 Milán Szabó, Gergely Nagy and Gyözö Garab 8.1 Introduction 246 8.2 Circular Dichroism Spectroscopy 248 8.3 Small-Angle Neutron Scattering (SANS) 253 8.4 Electrochromic Shift Absorbance Transients 256 8.5 Conclusions and Outlook 259 9 Hypotheses on Frustule Functionalities: From Single Species Analysis to Systematic Approaches 267 Johannes W. Goessling, Matt P. Ashworth, Marianne Ellegaard, Joao Serôdio and Martin Lopez Garcia 9.1 Introduction 268 9.2 Frustule Fundamentals: Chemistry, Formation, Reproduction 271 9.3 Examples of Unique Frustule Systems 274 9.4 Physicochemical Properties 277 9.5 Physical Properties 279 9.6 Frustule as an Optical System 281 9.7 Conclusions and Outlook 289 Part 3: Primary Production and Ecology 301 10 Extracellular Polymeric Substance Production by Benthic Pennate Diatoms 303 Graham J. C. Underwood 10.1 Introduction 304 10.2 Types of EPS Produced by Benthic Diatoms 304 10.3 Functions of EPS in Benthic Diatoms in Relation to Chemical Composition 308 10.4 Metabolic Pathways of EPS Production and Regulation in Diatoms 310 10.5 Interactions Between Diatoms, EPS and Bacteria 313 10.6 Future Directions 315 11 Diatom Primary Production in Headwater Streams: A Limited but Essential Process 327 Joey Allen, Michael Danger, Carlos Eduardo Wetzel, Vincent Felten and Martin Laviale 11.1 Ecological Relevance of Headwater Stream Ecosystems 328 11.2 Diatom Primary Production is Highly Constrained in Headwater Streams 330 11.3 Diatoms as High-Quality Resources for Other Organisms 334 11.4 Anthropogenic Impacts on Diatom Contributions to Headwater Stream Functioning 336 11.5 Headwater Diatom Community Functioning is Supported by Unique Biodiversity 338 11.6 Conclusion and Perspectives 340 12 Present and Future Perspectives for Bioassessment of Running Water Using Diatoms 351 Salomé FP Almeida and Maria J. Feio 12.1 Introduction 352 12.2 Potential of Diatoms as Indicators in Running Water Quality Assessment 352 12.3 Water Quality Assessment Methods 353 12.4 Molecular-Based Methods 355 12.5 Transitioning from Morphology-Based to eDNA-Based Biomonitoring: Available Options 368 12.6 Conclusions 370 13 Photosynthetic and Growth Responses of Planktonic Diatoms to Ocean Global Changes 383 Peng Jin, John Beardall and Kunshan Gao 13.1 Introduction 384 13.2 The Effects of Elevated CO2 and Ocean Acidification 384 13.3 The Effects of Ocean Warming 388 13.4 The Effects of UVR 389 13.5 Combined Effects of Ocean Acidification and Warming 390 13.6 Combined Effects of Ocean Acidification and UVR 391 13.7 Combined Effects of Ocean Acidification and Deoxygenation 392 13.8 Ocean Acidification Effects Under Multiple Drivers 393 13.9 Ecological Implications 395 13.10 Conclusions and Recommendations 396 Part 4: Cultivation and Application 407 14 Culturing Diatoms 409 Daniel Vaulot, Gust Bilcke, Peter Chaerle, Angela Falciatore, Priscillia Gourvil, Michael W. Lomas, Ian Probert and Wim Vyverman 14.1 Introduction 409 14.2 Current Diversity of Diatoms in Culture 411 14.3 Isolation of Diatom Cultures 415 14.4 Culture of Diatoms 422 14.5 Life Cycles 424 14.6 Cryopreservation 426 14.7 Diatom Strains Amenable to Genetic Engineering 430 14.8 Conclusion 434 15 Diatom Biofilm: Ecology and Cultivation from Laboratory to Industrial Level 449 Mary Dianne Grace Arnaldo, Aurélie Mossion, Thierry Beignon, Hugo Vuillemin, Freddy Guihéneuf, Gaëtane Wielgosz-Collin and Vona Méléder 15.1 Introduction 449 15.2 Natural Biofilms 453 15.3 Artificial Algal Biofilm Systems 458 15.4 Conclusion and Perspective 467 16 Opportunities and Challenges of Diatom Cell Factory for Human Health 477 Clementina Sansone, Angelo Del Mondo, Luigi Pistelli, Arianna Smerilli, Maria Saggiomo and Christophe Brunet 16.1 Introduction 478 16.2 Carotenoids 479 16.3 Vitamins 485 16.4 Polyphenols 490 16.5 Phytosterols 494 16.6 Polysaccharides 496 16.7 Polar Diatoms: New Model for Biotechnology? 500 16.8 Filling the Gap between Diatoms Biological Traits and Biotechnological Use 503 16.9 Conclusions 507 17 Diatom-Based Bioproducts and the Potential of Frustules in Drug Delivery 529 Pankaj Kumar Singh, Abhishek Saxena and Archana Tiwari 17.1 Introduction 529 17.2 High-Value Products Derived from Diatoms 531 17.3 Diatom as Drug Delivery Carriers 535 17.4 Therapeutic Applications of Diatoms 540 17.5 Conclusion 542 Part 5: Diatoms as Representative Organisms for the Protection of Marine Genetic Resources 551 18 A Journey to Mars with Diatoms on Board 553 Louisa Reissig, Mohamed Ghobara, Christian Maibohm and Johannes W. Goessling 18.1 Introduction 554 18.2 The Living Diatom 556 18.3 The Diatom Frustule: A Sustainable Source of Porous Silica 561 18.4 The Evolving Diatom 568 18.5 Conclusion 571 19 Legal Regime of Marine Genetic Resources in Areas Beyond National Jurisdiction 583 Gemma Andreone, Valentina Rossi and Giovanni Ardito 19.1 Introduction 584 19.2 The Current Legal Framework 585 19.3 The Notion of Marine Genetic Resources 586 19.4 Bioprospecting and Marine Scientific Research: Access to and Collection of Marine Genetic Resources 589 19.5 Spatial Scope (High Seas-Area) and Legal Status of MGRs in ABNJ (Common Heritage of Mankind vs Freedom of the Seas) 593 19.6 Conclusion 597 Acknowledgments 598 References 598 Subject Index 601 Taxonomic Index 611