Algae Quiz PDF

Hair-like structures, often chains of cells in cyanobacteria: Trichomes Root-like structures in some algae for anchorage: Rhizoid siliceous outer wall of diatoms: Frustule specialized feeding structure in some protozoans: Cytopharynx Hypothesis explaining the origin of organelles like mitochondr...

Hair-like structures, often chains of cells in cyanobacteria: Trichomes Root-like structures in some algae for anchorage: Rhizoid siliceous outer wall of diatoms: Frustule specialized feeding structure in some protozoans: Cytopharynx Hypothesis explaining the origin of organelles like mitochondria and chloroplasts: Theory of endosymbiosis groove in dinoflagellates housing flagella: Sulcus groove in the surface of dinoflagellates or diatoms, often housing flagella: Cingulum spherical structure formed by the arrangement of coccoliths around the cell: Coccosphere The initial engulfment of a prokaryote by a eukaryote leading to organelles like chloroplasts: Primary Endosymbiosis Calcium carbonate plates produced by coccolithophores: Coccolith stem-like structure in algae: Cauloid bottom half of a diatom's siliceous cell wall or frustule: Hypotheca Specialized nitrogen-fixing cells in some cyanobacteria: Heterocyst Molecules like chlorophyll, carotenoids, and phycobilins that capture light for photosynthesis: Pigments non-pigmented region in algal cells where the nucleus is located: Centroplasm A light-sensitive structure, often associated with phototaxis: Stigma Hair-like structures on flagella, increasing propulsion efficiency: Mastigonemes Organelles in some algae used for defense or movement: Ejectisomes A structure covering the plasma membrane in some algae: Periplast outer layer of certain algal thalli: Cortex Pigmented part od the cytoplasm in photosynthetic organisms: Chromatoplasm Endosymbiotic cyanobacteria or photosynthetic components of Glaucophytes: cyanella Unique organelle in haptophytes involved in feeding or sensory functions: Haptonema The bottom valve of the diatom frustule: Hypotheca The Upper valve of a diatome frustele: Epitheca The innermost part of a multilayered algal thallus: Medulla Vestigial nucleus found in some algal endosymbionts: Nucleomorph Protein complexes involved in light harvesting in cyanobacteria and red algae: Phycobilisome Gel-forming substances derived from algae (agar carrageenan):Pycocolloids Leag-like structures in algae: Phylloid groove in some diatom species aiding in movement: Raphe Eukaryote engulfing another eukaryotic cell, leading to complex plastids: secondary endosymbiosis DIATOMS CELL COVERING: The characteristic structure of diatoms are their cell covers or frustules, which have elaborate, ornate designs and numerous tiny pores (important in taxonomy). Some diatoms secrete a gelatinous substance called mucilage through the pores. Each frustule consists of two valves, one slightly larger than the other, which fit together like the Petri dishe’s top and back. The upper part is called the epitheca and the lower part is hypotheca Coccosphere Functions: protection agains microzooplankton predation, flotation bouyancy, light regulation and bichemistry Dinokont form: with a transversal and longitudinal flagellum. Desmokont form: flagella arise from a pore in the apical part. Metabolism: Many algae are nutritionally very versatils Mixotrophs: Algae can present autotrophic and heterotrophic behaviors. Algae can be adapted to the conditions of the environment, being able to live in any condition, depending on the concentration of organic components and intensity of light present in the environment -Autotrophs: source of energy light and source of Carbono inorganic -Heterotrophs: source of energy Organic and source of Carbono organic -Mixotrophs: source of energy light and organic and source of Carbono inorganic and organic -Photoheterotrops: source of energy light and source of Carbono organic Reproduction of algae: No seeds, Asexual and sexual reproduction, Asexual: spores, Sexual: gametes. Some groups do not have sexual reproduction (eg. Euglenophytes). Cyanobacters: no sexual reproduction but genetic exchange Reproduction: Complex life cycles: alternation of generations: Generations that form spores: sporophytes Generations. generations that form gametes: gametophytes. Spores are formed in sporangiaa, Gametes are formed in gametangia: Antheridia, Oogonia. Gametangia and sporangia do not have protection covers The centric diatoms exhibit radial symmetry, while the pennate diatoms have non-radial symmetry and usually instead exhibit symmetry of one or more of the valvar, apical, or transapical planes. Habitat: Cosmopolitan distribution, although they are mainly related to aquatic environments. Some genera: subaereous habitats (algae + fungi = lichen) Extreme habitats: Cyanobacteria they can live even in hot springs at 75ºC, on wetor arid soils, in barks of trees or rocks, in the Arctic and Antarctic. Habitat-Marine environment: Phytoplankton: dinoflagellates diatoms, coccolithophorids, cyanobacteria. Phytobenthos: green algae (Chlorophyta), brown algae(Pheophyceae), red algae (Rhodophytas). Upper limit: splash zone. Lower limit: until depths that reach 0.0005% approx. of surface light (eg 250m) Habitat-Freshwater: Phytoplankton: dinoflagellates diatoms, chlorophytes, cyanobacteria. Phytobenthos or periphyton (epilitic or epiphytic algae): chlorophytes, diatoms, cyanobacteria, some specialized algae genera (eg six genera of brown algae / approximately 100 species of red algae) Types of habitats: Extreme, Marine environment, freshwater Classification and nomenclature: Cyanobacters: Empire Prokaryota, Kingdom Bacteria, Phylum Cyanophyta Euglenophytes: Empire Eukaryota, Kingdom Protozoa, Phylum Euglenophyta Dinoflagellates: Empire Eukaryota, Kingdom Chromista, Phylum Dinophyta Coccolithophores: Empire Eukaryota, Kingdom Chromista, Phylum Haptophyta Cryptophytes: Empire Eukaryota, Kingdom Chromista, Phylum Cryptophyta Diatoms: Empire Eukaryota, Kingdom Chromista, Phylum Heterokontophyta, Class Bacillariophyceae Chrysophyceae: Empire Eukaryota, Kingdom Chromista, Phylum Heterokontophyta, Class Chrysophyceae Xanthophyceae: Empire Eukaryota, Kingdom Chromista, Phylum Heterokontophyta, Class Xanthophyceae Brown algae: Empire Eukaryota, Kingdom Chromista, Phylum Heterokontophyta, Class Phaeophyceae Glaucophytes: Empire Eukaryota, Kingdom Plantae, Phylum Glaucophyta Green algae: Empire Eukaryota, Kingdom Plantae, Phylum Chlorophyta Red algae: Empire Eukaryota, Kingdom Plantae, Phylum Rhodophyta In algae we can find two types of levels of organization: Protophytes, Thallophytes PROTOPHYTES: Unicellular organisms or inconsistent aggregates of cells without functional specialization. Unicellulars: Coccoid or Monadoid. Colonial: Palmelloid, Cenobia. Unicellular coccoid: Chlorella sp.(Chlorophyceae), Pinnularia sp., Diatomea pennada, Micrasterias thomasiana (Desmidiacea, Chlorophyceae), Thalassiosira lentiginosa, Diatomea céntrica. Unicellular monadoid: Phacus sp.(Euglenophyta), Ceratium sp.(Dinophyta), Euglena gracilis(Euglenophyta), Chlamydomonas(Chlorophyceae) COLONIAL Can be: 1- Palmelloid: colonies without defined form. Cells are grouped in a gelatinous matrix that forms an irregular colony. 2-Cenobia: colonies with defined form. They can have a specific number of cells depending of the genus. Flagella can be oriented outwards in the most complex forms. Cenobia can be flat or spherical. Colonial PALMELLOID: Sphaerocystis sp. (Chlorophyceae), Gloeocystis sp.(Chlorophyceae) Colonial Cenobia: Synura sp.(Chrysophyceae), Gonium pectorale (Volvocales. Chlorophyceae), Pediastrum duplex(Chlorophyceae), Plane cenobium *THALLOPHYTES: Multicellulars, with work division between cells and hierarchy of functions, Some intercellular cohesion through its walls Cells with differentiation and division of work (al least vegetative/reproductive cells) Aquatic environments (Poikilohydric). Lack of ability to mantain or regulate water content to achieve homeostasis Some are resistant to dessication Small size. Sustained by water. Without supporting tissues.The body of these organisms are called thallus. THALLOPHYTES in Cellular colonies, Filamentous thallus: Branched, Non branched; Pseudoparenchymatous thallus, Parenchymatous thallus, Siphonal thallus Kindoms of algae: Plantae, Chromista, Bacteria, Protozoa Biodiversity and Domain: Archaea, Bacteria, Protozoa, Chromista, Fungi, Plantae, Animalia Taxonomy: classification of living organisms Phyla of Marine invertebrates: Sponges, Cnidarians, Annelids, Molluscs, Cordates, Echinoderms Natural products from marine invetebrates to isolation and functions Sponges are asymmetry Cnidarians are radial Flatworms, Echinoderms, Molusks are bilateral Biodiversity: total genetic content (hereditary basis) of a biological group, community or biosphere (planet). Why preserving biodiversity? for benefits and conservation Explore marine biodiversity challenges: technological limitation (exploring is extremely complicated) exist more marine genetic diversity then terrestrial Biodiversity applications: Biotechnology, bio-indicators, Pharmaceutical use, Industry, Source of protein. Great challenge about biodiversity: not only identify the new organisms, increased the study of genetic and biochemical knowledge the most important part is organize and guide the results 1. What are the key health benefits of fucoxanthin extracted from brown algae? Fucoxanthin is a well know Carotenoids and is a multimodal perturbator of cellular pathways. Fucoxanthin can help to normalize glycemia and inflammation in diabetic mice, Inhibiting invasivity, metastasis and angiogenesis of cancer cells and tumors 2. How do microalgae pigments contribute to cancer treatment? Carotenoids have cytostatic and pro-apoptotic activities in cancer cells. Prevention of tumor cell appearance-growth-invasivity- metastasis, Inhibition of tumorigenic initiation by carcinogens, Inhibition of tumor angiogenesis, Sensitization of tumor cells to cytotoxic drugs and reversion of MDR. Pigments can have proprieties photosensibilisants PDT, Antiangiogenique, antimetastases ans anti-inflamatory. Fucoxanthin for example can decrease the tumor neoangiogenesis, cancer cell motility, tumor growth and the invasivity and diapedesis of cancer cells. 3. What are the main differences between primary and secondary metabolites in algae? Primary metabolites: Cell architecture (membranes, cell walls exopolysaccharides), biofilms, and energetic stocks as polysaccharides, lipid drops. Secondary metabolytes: are not directly involved in essential physiological processes of an organism, but are more commonly associated with defense and survival, competition, and communication. Terpenes, pigments, toxins, polyamines, alkaloids, sterols, heterocycles 4. What is the interest of ω-3 polyunsaturated fatty acids (PUFA) derived from microalgae in human health? reduce pregnancy complications (hypertension, premature birth, pre-eclampsia, post-partum depression, prevent atherosclerosis, myocard infarct as they scavenge free radicals responsible for tissular and vascular lesions, thrombosis and vasoconstriction, prevent the risk of graft rejection. Increase the response to viral and bacterial threats and reduce the risk of infection. w-3 PUFA integrate and fluidize cytoplasmic membranes, this can help in the absorption of chemotherapy That is why is of interest in pregnancy and fetal development, cardio protective effect, immunity, inflammation and sensitize tumor 5. How can phototherapy using microalgae pigments be applied to treat acne? Treating acne with antibacterial Phototherapy using microalgae PS. Natural eco-friendly photoactive microalgae extract to improve mild to moderate acne. This pigment with the phototherapy target S. aureus, S. epidermidis, C. acnes 6. How is microwave-assisted extraction (MAE) used to obtain pigments from microalgae? MAE is the only process allowing the total extraction of Ht pigments in temperature-controlled conditions. Microwaves cause the vibration of water and other polar molecules within wet biomass, thereby resulting in temperature increases in the intracellular liquids which subsequently causes the water to evaporate and exert pressure on the cell walls leading to cell disruption. 7. What is the functional and ecological significance of the pigment diversity found in marine phytoplankton? Contributing to their survival, adaptation, and influence on marine ecosystems. Photosynthesis optimization permits to absorb light across different wavelengths. Protect Agains Photodamage. Ensure effective energy conversion. Stress response. Ecological significance: reduce competition and support biodiversity, contribute to global carbon fixation and oxygen production. Taxonomy markers 8. How can microalgae be used as cell factories to synthesize therapeutic proteins? Microalgae are vegetal cells able to synthesize therapeutical proteins (e.g. hormones, cytokines, antibodies, vaccines). Easy to grow. No pathogenic virus, prion or endotoxin Marine microbes as source of natural products single-virus or single-cell genomic technique: with this technique is possible to obtain especifical bacteriophages or pathogens present in a sample for example coral mucus Why it is important to explore the marine microbial diversity: because the oceans are approx. the 71% of the Earth's surface. Microbial loop is between Mesopelagicor twilight zone until abyssopelagic zone. Ocean provides wide range of different habitats.The marine world is largely unexplored. Why are archaea more abundant than bacteria in the deep ocean? Archaea are more abundant than bacteria in the deep ocean due to their unique physiological and metabolic adaptations, which allow them to thrive under extreme conditions like upper temperatures limits of 122°C From the ocean surface to the deep, the decreasing light penetration, temperature and availability of labile organic matter have been identified as important factors that determine the vertical distribution of the bacterial diversity Bacterial diversity: Cyanobacteria: the only oxygenic phototrophs microorganism (chlorphyll a and other and phycobilins), Gram negative, Size: 0.5 – 100 m (unicellular and filamentous, All species are able to fix CO2 and many can fix N2 (diazotrophic) → nitrogenase enzymes are inhibited by O2. Cyanobacteria are of central importance to the productivity of the oceans. Heterocyst Nitrogen. Ecology of cyanobacteria: CO2 and N2 fixing (Trichosdesmium) Phylum Pseudomonadota: The most metabolically diverse phylum (chemolithotrophic, chemoorganotrophic and phototrophic), Gram negative bacteria (wide range of morphologies), Are the major phyla of Bacteria that have cultivated species. *SAR 11-> It is found in almost every pelagic environment ranging from shallow coastal waters to depths over 3000m *ubiquitous SAR11 → Pelagibacter ubique: Chemoorganoheterotrophic and aerobic bacteria, It is extremely challenging to grow in the lab, Proteorhodopsin, Catabolizes dimethylsulfoniopropionate (DMSP) *Vibrio: Gram-negative, rod-shaped bacteria, Vibrio genus is autochthonous to aquatic environments (from rivers, estuaries, seas, to deepoceanic waters). Water parameters such as temperature, pH, salinity, and nutrients present in the water column can ultimately affect Vibrio presence.Viable but not culturable state (VBNC). Chemical communication system → Quorum sensing-> Quorum quenching. Horizontal gene transfer (HGT) plays a crucial role in the evolution and adaptability of Vibrio species (pilus). Lysogenic conversion in Vibrio species. Phylum Plactomycetes: Their cells walls lack peptidoglycan, They show extensive cell compartmentalization, including in some cases a membrane-enclosed nuclear structure, Anammoxosome (protecting cell from toxic intermediates) → anaerobic oxidation of ammonia Phylum Actinobacteria: Gram positive and rod-shaped or filamentous bacteria, Based on 16S rRNA can be divided into nine orders but the vast majority of species belong to Actinomycetales, Microorganisms from this phylum are present in both pelagic and benthic environments, and they are usually found in symbiotic association with a wide range of marine organisms Sreptomyces: Over 500 species of Streptomyces are recognized, Filamentous and aerobic gram-positive Bacteria common in soils. About 50% of all Streptomyces isolated have been found to be antibiotic producers. Antibiotic resistance: Killing at least 1.27 million people worldwide and associated with nearly 5 million deaths in 2019 Archaea diversity: Archaeosomes for drug administration: Remarkable stability in stressful situations, Greater encapsulation efficiency. Excelents like probriotic in aquaculture and dont have endospore formation. What are the natural archaeal species associated with the fish intestine? Bacteria, fungi, and archaea (perticulary methanogenic) What are the suitable culture media and conditions for culturing archaea under controlled environments? Culturing archaea requires specialized media and environmental conditions, given their unique adaptations. Are there any side effects due to an increase in the archaeal community in the fish gut microbiome? The host range of a given virus is thus to a major extent determinened by the presence of a suitable receptor that the virus can recognize and attach to. Bacteria have various defense mechanisms, such as receptor changes by mutations, restriction-modification systems and CRISPR-Cas systems, which can act as barriers to phage infection. Viruses can control the abundance of specific bacterial strains Phage therapy as alternative to antibiotics CRISPR-CAS principle: The gRNA binds to the Cas protein, forming a complex. This complex scans the DNA for a sequence complementary to the gRNA, The gRNA-Cas complex binds to the target DNA at a site next to a specific motif called the PAM (Protospacer Adjacent Motif), essential for target recognition, The Cas protein introduces a double-strand break (DSB) in the DNA at the target site. FUNGI: ≈ 2500 MARINE STRAINS ar equal to 600 taxa Evolutionary studies have shown that Fungi and Animals are more closely related than any other group. Fungi are heterotrophs. Fungi have cell walls made of chitin, can be multicellular or unicellular, lack specialized tissues or organs, Heterotrophic organism that absorbs nutrients after external digestion (release enzymes to break down organic matter). mobility: non-motile relying on hyphae and mycelium growth or dispersal of spores. Reproduce via spores both sexually and asexually.Fungi are obligates aerobes of facultative anaerobes. have is own apecific marker called ITS regions. The largest living organism on Earth is a fungus: Armillaria solidipes Fungis are Widespread in all aquatic environments where they play key roles; fundamental for biotechnology The fungal material is one of the main components of the bioaerosol, and constitutes up to 90% of the PM10 fraction of the air particulate. In terrestrial habitats fungi play key roles as saprobe, Degrading any natural organic compound including the more recalcitrant ones (lignin, chitin and cheratin..) and also many xenobiotic (PAHs, oil). they can do nutrient cycling, bioremedation and biodeterioration. Fungis can be symbionts of plants, algae, animal. Fungi represent up to 80% of the biomass of a soil Most fungi are entirely microscopic. Hyphae and Mycelium The marine environment is a diversified ecosystem that hosts a multitude of microorganisms (up to 98% of the biomass is made of m.o.) among which fungi are often dominant. Fungi are key players in marine environments representing a substantial proportion of the microbial diversity Fungi have been found in all the marine habitats we searched them Marine Fungi are defined as any fungus able to: Grow and/or sporulate in marine environments; form symbiotic relationships with other marine organisms; Adapt and evolve or be metabolically active in marine environments. According to ecological preferences and behaviors they can be distinguished in obligate and facultative marine fungi. Marine fungi are distinct from their terrestrial and freshwater counterparts, both in their taxonomy, morphology and adaptation to an aquatic habitat. “obligate marine fungi are those that grow and sporulate exclusively in a marine or estuarine habitat “facultative marine fungi are terrestrial species which actively grow and reproduce in marine environment any fungus repeatedly recovered from marine habitats, because: able to grow and /or sporulate on substrata in marine environment, it forms symbiotic relationships with other marine organisms, it is shown to adapt and evolve at the genetic level or be metabolically active in marine environment Marine microorganisms,including fungi, can be considered, sensu latu, extremophiles since they are adapted to live at high salinity, low water activity, high pressure, and also at, variable pH, low temperature and with scarcity of nutriment. MARINE FUNGI IDENTIKIT: Extremophyle s.l. (high salinity, oligotrophic, low aw); Poorly studied despite high biodiversity; Great importance from an ecological and biotechnological point of view; Vast and phylogenetically diverse mycobiota likely differentiated by geography, substrate, and environmental conditions. Our understanding of marine fungal diversity and distributions is shaped by the methods employed. The use of culture-independent techniques allowed us to broaden our knowledge on both uncultured fungi and cryptic fungi (fungi with similar morphology that cannot be differentiated by microscopic techniques) present in the marine environment. It has enabled the discovery of new fungal groups thus boosting our current ability in assessing fungal biodiversity. Often the unidentified fungal groups represent a high proportion of the analyzed data, suggesting that the sea harbors a largely unknown fungal community, which could include members of potential biotechnological importance. Metabarcoding approach: ITS vs 18S (blocking primers) Mycoplankton encompasses fungal members of the plankton communities of marine and freshwater ecosystems. Filamentous free-living fungi and yeasts that are associated with planktonic particles or phytoplankton and behave as saprotrophs or patogens.These fungi play a significant role in heterotrophic mineralization and nutrient cycling MYCOLOOP: Chytrid epidemics are omnipresent, infecting diverse phytoplankton host communities. They are relevant for the evolution of their hosts as well as for population dynamics and succession in phytoplantkton communities. Mycoplankton abundance, structure, and function is strongly related to environmental factors. Mycobenthos: Hyphal fragments as the main route of dispersion because at high reassures the conidia do not germinate. MYCOPHYCOBIONTS: forced symbiosis between marine fungi and macroalgae MYCORRHIZAE: The marine phanerogams are devoid of it, while they are present in numerous halophilous plants For the identification of a microscopic fungus, it is necessary to have the organism in pure culture. Initially, the fungus can be grown on a generic medium, such as MEA, OA or PDA, incubated, for about a week, at a temperature of 20-25°C. These generic growth conditions should result in the fungus colony development, on which macroscopic and microscopic characteristics can be analyzed. Culture media Xenophile species (DG18-agar) Non xenophile species (MEA, DG18-agar) Toxic species (e.g. AFPA per Aspergillus flavus e A. parasiticus) Pathogen species (MEA + CX per Aspergillus fumigatus) Species with peculiar physiological traits (e.g. MEA + NaCl per Wallemia sebi) Incubation temperatures: 4-5 °C for psychrophilic or psychotolerant fungi 25°C for mesophilic fungi 37°C or more for thermophilic-thermotolerant species After the growing phase in plate the next step is the isolation of the fungal strain and, if necessary, its preservation for subsequent morphological, physiological or molecular studies are carried out. Asexual reproduction occurs by release of sporangiospores produced by cytoplasmic cleavage within sporangia present on top of specialized hyphae, the sporangiophores.