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Chlamydomonas reinhardtii: A species of GREEN ALGAE. Delicate, hairlike appendages arise from the flagellar surface in these organisms.Chlamydomonas: A genus GREEN ALGAE in the order VOLVOCIDA. It consists of solitary biflagellated organisms common in fresh water and damp soil.Algal Proteins: Proteins found in any species of algae.Chloroplasts: Plant cell inclusion bodies that contain the photosynthetic pigment CHLOROPHYLL, which is associated with the membrane of THYLAKOIDS. Chloroplasts occur in cells of leaves and young stems of plants. They are also found in some forms of PHYTOPLANKTON such as HAPTOPHYTA; DINOFLAGELLATES; DIATOMS; and CRYPTOPHYTA.Flagella: A whiplike motility appendage present on the surface cells. Prokaryote flagella are composed of a protein called FLAGELLIN. Bacteria can have a single flagellum, a tuft at one pole, or multiple flagella covering the entire surface. In eukaryotes, flagella are threadlike protoplasmic extensions used to propel flagellates and sperm. Flagella have the same basic structure as CILIA but are longer in proportion to the cell bearing them and present in much smaller numbers. (From King & Stansfield, A Dictionary of Genetics, 4th ed)RNA, Algal: Ribonucleic acid in algae having regulatory and catalytic roles as well as involvement in protein synthesis.Cytochromes f: Cytochromes f are found as components of the CYTOCHROME B6F COMPLEX. They play important role in the transfer of electrons from PHOTOSYSTEM I to PHOTOSYSTEM II.DNA, Algal: Deoxyribonucleic acid that makes up the genetic material of algae.Photosynthesis: The synthesis by organisms of organic chemical compounds, especially carbohydrates, from carbon dioxide using energy obtained from light rather than from the oxidation of chemical compounds. Photosynthesis comprises two separate processes: the light reactions and the dark reactions. In higher plants; GREEN ALGAE; and CYANOBACTERIA; NADPH and ATP formed by the light reactions drive the dark reactions which result in the fixation of carbon dioxide. (from Oxford Dictionary of Biochemistry and Molecular Biology, 2001)Chlorophyta: A phylum of photosynthetic EUKARYOTA bearing double membrane-bound plastids containing chlorophyll a and b. They comprise the classical green algae, and represent over 7000 species that live in a variety of primarily aquatic habitats. Only about ten percent are marine species, most live in freshwater.Cytochrome b6f Complex: A protein complex that includes CYTOCHROME B6 and CYTOCHROME F. It is found in the THYLAKOID MEMBRANE and plays an important role in process of PHOTOSYNTHESIS by transferring electrons from PLASTOQUINONE to PLASTOCYANIN or CYTOCHROME C6. The transfer of electrons is coupled to the transport of PROTONS across the membrane.Photosystem II Protein Complex: A large multisubunit protein complex found in the THYLAKOID MEMBRANE. It uses light energy derived from LIGHT-HARVESTING PROTEIN COMPLEXES to catalyze the splitting of WATER into DIOXYGEN and of reducing equivalents of HYDROGEN.Chlorophyll: Porphyrin derivatives containing magnesium that act to convert light energy in photosynthetic organisms.Light: That portion of the electromagnetic spectrum in the visible, ultraviolet, and infrared range.Photosystem I Protein Complex: A large multisubunit protein complex that is found in the THYLAKOID MEMBRANE. It uses light energy derived from LIGHT-HARVESTING PROTEIN COMPLEXES to drive electron transfer reactions that result in either the reduction of NADP to NADPH or the transport of PROTONS across the membrane.Molecular Sequence Data: Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.Photosynthetic Reaction Center Complex Proteins: Protein complexes that take part in the process of PHOTOSYNTHESIS. They are located within the THYLAKOID MEMBRANES of plant CHLOROPLASTS and a variety of structures in more primitive organisms. There are two major complexes involved in the photosynthetic process called PHOTOSYSTEM I and PHOTOSYSTEM II.Plant Proteins: Proteins found in plants (flowers, herbs, shrubs, trees, etc.). The concept does not include proteins found in vegetables for which VEGETABLE PROTEINS is available.Genes, Protozoan: The functional hereditary units of protozoa.Plastocyanin: A copper-containing plant protein that is a fundamental link in the electron transport chain of green plants during the photosynthetic conversion of light energy by photophosphorylation into the potential energy of chemical bonds.Thylakoids: Membranous cisternae of the CHLOROPLAST containing photosynthetic pigments, reaction centers, and the electron-transport chain. Each thylakoid consists of a flattened sac of membrane enclosing a narrow intra-thylakoid space (Lackie and Dow, Dictionary of Cell Biology, 2nd ed). Individual thylakoids are interconnected and tend to stack to form aggregates called grana. They are found in cyanobacteria and all plants.Axoneme: A bundle of MICROTUBULES and MICROTUBULE-ASSOCIATED PROTEINS forming the core of each CILIUM or FLAGELLUM. In most eukaryotic cilia or flagella, an axoneme shaft has 20 microtubules arranged in nine doublets and two singlets.Light-Harvesting Protein Complexes: Complexes containing CHLOROPHYLL and other photosensitive molecules. They serve to capture energy in the form of PHOTONS and are generally found as components of the PHOTOSYSTEM I PROTEIN COMPLEX or the PHOTOSYSTEM II PROTEIN COMPLEX.Protozoan Proteins: Proteins found in any species of protozoan.Amino Acid Sequence: The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.Mutation: Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.Arylsulfatases: Enzymes that catalyze the hydrolysis of a phenol sulfate to yield a phenol and sulfate. Arylsulfatase A, B, and C have been separated. A deficiency of arylsulfatases is one of the causes of metachromatic leukodystrophy (LEUKODYSTROPHY, METACHROMATIC). EC 3.1.6.1.Diuron: A pre-emergent herbicide.Dyneins: A family of multisubunit cytoskeletal motor proteins that use the energy of ATP hydrolysis to power a variety of cellular functions. Dyneins fall into two major classes based upon structural and functional criteria.Transformation, Genetic: Change brought about to an organisms genetic composition by unidirectional transfer (TRANSFECTION; TRANSDUCTION, GENETIC; CONJUGATION, GENETIC, etc.) and incorporation of foreign DNA into prokaryotic or eukaryotic cells by recombination of part or all of that DNA into the cell's genome.Amylopectin: A highly branched glucan in starch.Plastoquinone: Polyunsaturated side-chain quinone derivative which is an important link in the electron transport chain of green plants during the photosynthetic conversion of light energy by photophosphorylation into the potential energy of chemical bonds.Volvox: A genus of GREEN ALGAE in the family Volvocaceae. They form spherical colonies of hundreds or thousands of bi-flagellated cells in a semi-transparent gelatinous ball.Ribulose-Bisphosphate Carboxylase: A carboxy-lyase that plays a key role in photosynthetic carbon assimilation in the CALVIN-BENSON CYCLE by catalyzing the formation of 3-phosphoglycerate from ribulose 1,5-biphosphate and CARBON DIOXIDE. It can also utilize OXYGEN as a substrate to catalyze the synthesis of 2-phosphoglycolate and 3-phosphoglycerate in a process referred to as photorespiration.Darkness: The absence of light.Sulfur: An element that is a member of the chalcogen family. It has an atomic symbol S, atomic number 16, and atomic weight [32.059; 32.076]. It is found in the amino acids cysteine and methionine.Cytochromes c6: Cytochromes of the c type that are involved in the transfer of electrons from CYTOCHROME B6F COMPLEX and PHOTOSYSTEM I.Microalgae: A non-taxonomic term for unicellular microscopic algae which are found in both freshwater and marine environments. Some authors consider DIATOMS; CYANOBACTERIA; HAPTOPHYTA; and DINOFLAGELLATES as part of microalgae, even though they are not algae.RNA, Chloroplast: Ribonucleic acid in chloroplasts having regulatory and catalytic roles as well as involvement in protein synthesis.Base Sequence: The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.Sequence Homology, Amino Acid: The degree of similarity between sequences of amino acids. This information is useful for the analyzing genetic relatedness of proteins and species.Chloroplast Proteins: Proteins encoded by the CHLOROPLAST GENOME or proteins encoded by the nuclear genome that are imported to and resident in the CHOROPLASTS.DNA, Chloroplast: Deoxyribonucleic acid that makes up the genetic material of CHLOROPLASTS.Hydrogenase: An enzyme found in bacteria. It catalyzes the reduction of FERREDOXIN and other substances in the presence of molecular hydrogen and is involved in the electron transport of bacterial photosynthesis.Carbonic Anhydrases: A family of zinc-containing enzymes that catalyze the reversible hydration of carbon dioxide. They play an important role in the transport of CARBON DIOXIDE from the tissues to the LUNG. EC 4.2.1.1.Cytochrome b Group: Cytochromes (electron-transporting proteins) with protoheme (HEME B) as the prosthetic group.Electron Transport: The process by which ELECTRONS are transported from a reduced substrate to molecular OXYGEN. (From Bennington, Saunders Dictionary and Encyclopedia of Laboratory Medicine and Technology, 1984, p270)Malate Dehydrogenase (NADP+)Genetic Complementation Test: A test used to determine whether or not complementation (compensation in the form of dominance) will occur in a cell with a given mutant phenotype when another mutant genome, encoding the same mutant phenotype, is introduced into that cell.Carbon Dioxide: A colorless, odorless gas that can be formed by the body and is necessary for the respiration cycle of plants and animals.Starch: Any of a group of polysaccharides of the general formula (C6-H10-O5)n, composed of a long-chain polymer of glucose in the form of amylose and amylopectin. It is the chief storage form of energy reserve (carbohydrates) in plants.Hydrogen: The first chemical element in the periodic table. It has the atomic symbol H, atomic number 1, and atomic weight [1.00784; 1.00811]. It exists, under normal conditions, as a colorless, odorless, tasteless, diatomic gas. Hydrogen ions are PROTONS. Besides the common H1 isotope, hydrogen exists as the stable isotope DEUTERIUM and the unstable, radioactive isotope TRITIUM.Cloning, Molecular: The insertion of recombinant DNA molecules from prokaryotic and/or eukaryotic sources into a replicating vehicle, such as a plasmid or virus vector, and the introduction of the resultant hybrid molecules into recipient cells without altering the viability of those cells.Cytochromes: Hemeproteins whose characteristic mode of action involves transfer of reducing equivalents which are associated with a reversible change in oxidation state of the prosthetic group. Formally, this redox change involves a single-electron, reversible equilibrium between the Fe(II) and Fe(III) states of the central iron atom (From Enzyme Nomenclature, 1992, p539). The various cytochrome subclasses are organized by the type of HEME and by the wavelength range of their reduced alpha-absorption bands.Genes, Plant: The functional hereditary units of PLANTS.Chlorella: Nonmotile unicellular green algae potentially valuable as a source of high-grade protein and B-complex vitamins.Starch Synthase: An enzyme that catalyzes the transfer of glucose from ADPglucose to glucose-containing polysaccharides in 1,4-alpha-linkages. EC 2.4.1.21.Geranylgeranyl-Diphosphate Geranylgeranyltransferase: An enzyme that catalyzes the condensation of two molecules of geranylgeranyl diphosphate to give prephytoene diphosphate. The prephytoene diphosphate molecule is a precursor for CAROTENOIDS and other tetraterpenes.Organelle Size: The quantity of volume or surface area of ORGANELLES.Ferredoxins: Iron-containing proteins that transfer electrons, usually at a low potential, to flavoproteins; the iron is not present as in heme. (McGraw-Hill Dictionary of Scientific and Technical Terms, 5th ed)Oxidation-Reduction: A chemical reaction in which an electron is transferred from one molecule to another. The electron-donating molecule is the reducing agent or reductant; the electron-accepting molecule is the oxidizing agent or oxidant. Reducing and oxidizing agents function as conjugate reductant-oxidant pairs or redox pairs (Lehninger, Principles of Biochemistry, 1982, p471).Sequence Alignment: The arrangement of two or more amino acid or base sequences from an organism or organisms in such a way as to align areas of the sequences sharing common properties. The degree of relatedness or homology between the sequences is predicted computationally or statistically based on weights assigned to the elements aligned between the sequences. This in turn can serve as a potential indicator of the genetic relatedness between the organisms.RNA, Protozoan: Ribonucleic acid in protozoa having regulatory and catalytic roles as well as involvement in protein synthesis.Phylogeny: The relationships of groups of organisms as reflected by their genetic makeup.Kinetics: The rate dynamics in chemical or physical systems.Mutagenesis, Insertional: Mutagenesis where the mutation is caused by the introduction of foreign DNA sequences into a gene or extragenic sequence. This may occur spontaneously in vivo or be experimentally induced in vivo or in vitro. Proviral DNA insertions into or adjacent to a cellular proto-oncogene can interrupt GENETIC TRANSLATION of the coding sequences or interfere with recognition of regulatory elements and cause unregulated expression of the proto-oncogene resulting in tumor formation.Microtubules: Slender, cylindrical filaments found in the cytoskeleton of plant and animal cells. They are composed of the protein TUBULIN and are influenced by TUBULIN MODULATORS.Phototrophic Processes: Processes by which phototrophic organisms use sunlight as their primary energy source. Contrasts with chemotrophic processes which do not depend on light and function in deriving energy from exogenous chemical sources. Photoautotrophy (or photolithotrophy) is the ability to use sunlight as energy to fix inorganic nutrients to be used for other organic requirements. Photoautotrophs include all GREEN PLANTS; GREEN ALGAE; CYANOBACTERIA; and green and PURPLE SULFUR BACTERIA. Photoheterotrophs or photoorganotrophs require a supply of organic nutrients for their organic requirements but use sunlight as their primary energy source; examples include certain PURPLE NONSULFUR BACTERIA. Depending on environmental conditions some organisms can switch between different nutritional modes (AUTOTROPHY; HETEROTROPHY; chemotrophy; or phototrophy) to utilize different sources to meet their nutrients and energy requirements.Isoamylase: An enzyme that hydrolyzes 1,6-alpha-glucosidic branch linkages in glycogen, amylopectin, and their beta-limit dextrins. It is distinguished from pullulanase (EC 3.2.1.41) by its inability to attack pullulan and by the feeble action of alpha-limit dextrins. It is distinguished from amylopectin 6-glucanohydrolase (EC 3.2.1.69) by its action on glycogen. With EC 3.2.1.69, it produces the activity called "debranching enzyme". EC 3.2.1.68.Pyruvate Synthase: A ferredoxin-containing enzyme that catalyzes the COENZYME A-dependent oxidative decarboxylation of PYRUVATE to acetyl-COENZYME A and CARBON DIOXIDE.Gene Expression Regulation, Plant: Any of the processes by which nuclear, cytoplasmic, or intercellular factors influence the differential control of gene action in plants.Electrophoresis, Polyacrylamide Gel: Electrophoresis in which a polyacrylamide gel is used as the diffusion medium.Phenotype: The outward appearance of the individual. It is the product of interactions between genes, and between the GENOTYPE and the environment.Fluorescence: The property of emitting radiation while being irradiated. The radiation emitted is usually of longer wavelength than that incident or absorbed, e.g., a substance can be irradiated with invisible radiation and emit visible light. X-ray fluorescence is used in diagnosis.Oxygen: An element with atomic symbol O, atomic number 8, and atomic weight [15.99903; 15.99977]. It is the most abundant element on earth and essential for respiration.Thioredoxin h: A thioredoxin subtype that is ubiquitously found in the plant kingdom. It reduces a variety of seed storage proteins and may play a role in the germination process of seeds.RNA, Messenger: RNA sequences that serve as templates for protein synthesis. Bacterial mRNAs are generally primary transcripts in that they do not require post-transcriptional processing. Eukaryotic mRNA is synthesized in the nucleus and must be exported to the cytoplasm for translation. Most eukaryotic mRNAs have a sequence of polyadenylic acid at the 3' end, referred to as the poly(A) tail. The function of this tail is not known for certain, but it may play a role in the export of mature mRNA from the nucleus as well as in helping stabilize some mRNA molecules by retarding their degradation in the cytoplasm.Coproporphyrinogen Oxidase: An enzyme that catalyzes the oxidative decarboxylation of coproporphyrinogen III to protoporphyrinogen IX by the conversion of two propionate groups to two vinyl groups. It is the sixth enzyme in the 8-enzyme biosynthetic pathway of HEME, and is encoded by CPO gene. Mutations of CPO gene result in HEREDITARY COPROPORPHYRIA.Cilia: Populations of thin, motile processes found covering the surface of ciliates (CILIOPHORA) or the free surface of the cells making up ciliated EPITHELIUM. Each cilium arises from a basic granule in the superficial layer of CYTOPLASM. The movement of cilia propels ciliates through the liquid in which they live. The movement of cilia on a ciliated epithelium serves to propel a surface layer of mucus or fluid. (King & Stansfield, A Dictionary of Genetics, 4th ed)DNA, Protozoan: Deoxyribonucleic acid that makes up the genetic material of protozoa.Eukaryota: One of the three domains of life (the others being BACTERIA and ARCHAEA), also called Eukarya. These are organisms whose cells are enclosed in membranes and possess a nucleus. They comprise almost all multicellular and many unicellular organisms, and are traditionally divided into groups (sometimes called kingdoms) including ANIMALS; PLANTS; FUNGI; and various algae and other taxa that were previously part of the old kingdom Protista.Genome, Chloroplast: The genetic complement of CHLOROPLASTS as represented in their DNA.Molecular Weight: The sum of the weight of all the atoms in a molecule.Iron-Sulfur Proteins: A group of proteins possessing only the iron-sulfur complex as the prosthetic group. These proteins participate in all major pathways of electron transport: photosynthesis, respiration, hydroxylation and bacterial hydrogen and nitrogen fixation.Anaerobiosis: The complete absence, or (loosely) the paucity, of gaseous or dissolved elemental oxygen in a given place or environment. (From Singleton & Sainsbury, Dictionary of Microbiology and Molecular Biology, 2d ed)DNA, Complementary: Single-stranded complementary DNA synthesized from an RNA template by the action of RNA-dependent DNA polymerase. cDNA (i.e., complementary DNA, not circular DNA, not C-DNA) is used in a variety of molecular cloning experiments as well as serving as a specific hybridization probe.Genome, Protozoan: The complete genetic complement contained in a set of CHROMOSOMES in a protozoan.Centrioles: Self-replicating, short, fibrous, rod-shaped organelles. Each centriole is a short cylinder containing nine pairs of peripheral microtubules, arranged so as to form the wall of the cylinder.Tubulin: A microtubule subunit protein found in large quantities in mammalian brain. It has also been isolated from SPERM FLAGELLUM; CILIA; and other sources. Structurally, the protein is a dimer with a molecular weight of approximately 120,000 and a sedimentation coefficient of 5.8S. It binds to COLCHICINE; VINCRISTINE; and VINBLASTINE.Microscopy, Electron: Microscopy using an electron beam, instead of light, to visualize the sample, thereby allowing much greater magnification. The interactions of ELECTRONS with specimens are used to provide information about the fine structure of that specimen. In TRANSMISSION ELECTRON MICROSCOPY the reactions of the electrons that are transmitted through the specimen are imaged. In SCANNING ELECTRON MICROSCOPY an electron beam falls at a non-normal angle on the specimen and the image is derived from the reactions occurring above the plane of the specimen.beta-Tocopherol: A natural tocopherol with less antioxidant activity than alpha-tocopherol. It exhibits antioxidant activity by virtue of the phenolic hydrogen on the 2H-1-benzopyran-6-ol nucleus. As in GAMMA-TOCOPHEROL, it also has three methyl groups on the 6-chromanol nucleus but at different sites.Spectinomycin: An antibiotic produced by Streptomyces spectabilis. It is active against gram-negative bacteria and used for the treatment of gonorrhea.Crosses, Genetic: Deliberate breeding of two different individuals that results in offspring that carry part of the genetic material of each parent. The parent organisms must be genetically compatible and may be from different varieties or closely related species.Plastids: Self-replicating cytoplasmic organelles of plant and algal cells that contain pigments and may synthesize and accumulate various substances. PLASTID GENOMES are used in phylogenetic studies.RNA, Plant: Ribonucleic acid in plants having regulatory and catalytic roles as well as involvement in protein synthesis.Photophosphorylation: The use of light to convert ADP to ATP without the concomitant reduction of dioxygen to water as occurs during OXIDATIVE PHOSPHORYLATION in MITOCHONDRIA.Carbon: A nonmetallic element with atomic symbol C, atomic number 6, and atomic weight [12.0096; 12.0116]. It may occur as several different allotropes including DIAMOND; CHARCOAL; and GRAPHITE; and as SOOT from incompletely burned fuel.