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Apicoplast
An apicoplast is a Synapomorphy, derived non-photosynthetic plastid found in most Apicomplexa, including ''Toxoplasma gondii'', and ''Plasmodium falciparum'' and other ''Plasmodium'' spp. (parasites causing malaria), but not in others such as ''Cryptosporidium''. It originated from algae through secondary endosymbiosis; there is debate as to whether this was a Green algae, green or Red algae, red alga. The apicoplast is surrounded by four membranes within the outermost part of the endomembrane system. The apicoplast hosts important metabolic pathways like fatty acid synthesis, isoprenoid precursor synthesis and parts of the heme biosynthetic pathway. Significance Apicoplasts are a Relict (biology), relict, nonphotosynthetic plastid found in most protozoan parasites belonging to the phylum Apicomplexa. Among the most infamous Apicomplexan parasites is ''Plasmodium falciparum'', a causative agent of severe malaria. Because apicoplasts are vital to parasite survival, they provide an en ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Apicomplexa
The Apicomplexa (also called Apicomplexia) are a large phylum of parasitic alveolates. Most of them possess a unique form of organelle that comprises a type of non-photosynthetic plastid called an apicoplast, and an apical complex structure. The organelle is an adaptation that the apicomplexan applies in penetration of a host cell. The Apicomplexa are unicellular and spore-forming. All species are obligate endoparasites of animals, except '' Nephromyces'', a symbiont in marine animals, originally classified as a chytrid fungus. Motile structures such as flagella or pseudopods are present only in certain gamete stages. The Apicomplexa are a diverse group that includes organisms such as the coccidia, gregarines, piroplasms, haemogregarines, and plasmodia. Diseases caused by Apicomplexa include: * Babesiosis (''Babesia'') * Malaria (''Plasmodium'') * Cryptosporidiosis (''Cryptosporidium parvum'') * Cyclosporiasis (''Cyclospora cayetanensis'') * Cystoisosporiasis (''Cystoisosp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plasmodium Falciparum
''Plasmodium falciparum'' is a Unicellular organism, unicellular protozoan parasite of humans, and the deadliest species of ''Plasmodium'' that causes malaria in humans. The parasite is transmitted through the bite of a female ''Anopheles'' mosquito and causes the disease's most dangerous form, falciparum malaria. It is responsible for around 50% of all malaria cases. ''P. falciparum'' is therefore regarded as the deadliest parasite in humans. It is also associated with the development of blood cancer (Burkitt's lymphoma) and is classified as a List of IARC Group 2A carcinogens, Group 2A (probable) carcinogen. The species originated from the malarial parasite ''Laverania'' found in gorillas, around 10,000 years ago. Alphonse Laveran was the first to identify the parasite in 1880, and named it ''Oscillaria malariae''. Ronald Ross discovered its transmission by mosquito in 1897. Giovanni Battista Grassi elucidated the complete transmission from a female Anopheles, anopheline mosquit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chloroplast
A chloroplast () is a type of membrane-bound organelle known as a plastid that conducts photosynthesis mostly in plant and algal cells. The photosynthetic pigment chlorophyll captures the energy from sunlight, converts it, and stores it in the energy-storage molecules ATP and NADPH while freeing oxygen from water in the cells. The ATP and NADPH is then used to make organic molecules from carbon dioxide in a process known as the Calvin cycle. Chloroplasts carry out a number of other functions, including fatty acid synthesis, amino acid synthesis, and the immune response in plants. The number of chloroplasts per cell varies from one, in unicellular algae, up to 100 in plants like ''Arabidopsis'' and wheat. A chloroplast is characterized by its two membranes and a high concentration of chlorophyll. Other plastid types, such as the leucoplast and the chromoplast, contain little chlorophyll and do not carry out photosynthesis. Chloroplasts are highly dynamic—they circulat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plasmodium
''Plasmodium'' is a genus of unicellular eukaryotes that are obligate parasites of vertebrates and insects. The life cycles of ''Plasmodium'' species involve development in a blood-feeding insect host which then injects parasites into a vertebrate host during a blood meal. Parasites grow within a vertebrate body tissue (often the liver) before entering the bloodstream to infect red blood cells. The ensuing destruction of host red blood cells can result in malaria. During this infection, some parasites are picked up by a blood-feeding insect (mosquitoes in majority cases), continuing the life cycle. ''Plasmodium'' is a member of the phylum Apicomplexa, a large group of parasitic eukaryotes. Within Apicomplexa, ''Plasmodium'' is in the order Haemosporida and family Plasmodiidae. Over 200 species of ''Plasmodium'' have been described, many of which have been subdivided into 14 subgenera based on parasite morphology and host range. Evolutionary relationships among different ''Pl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Malaria
Malaria is a mosquito-borne infectious disease that affects humans and other animals. Malaria causes symptoms that typically include fever, tiredness, vomiting, and headaches. In severe cases, it can cause jaundice, seizures, coma, or death. Symptoms usually begin ten to fifteen days after being bitten by an infected mosquito. If not properly treated, people may have recurrences of the disease months later. In those who have recently survived an infection, reinfection usually causes milder symptoms. This partial resistance disappears over months to years if the person has no continuing exposure to malaria. Malaria is caused by single-celled microorganisms of the ''Plasmodium'' group. It is spread exclusively through bites of infected ''Anopheles'' mosquitoes. The mosquito bite introduces the parasites from the mosquito's saliva into a person's blood. The parasites travel to the liver where they mature and reproduce. Five species of ''Plasmodium'' can infect and be spread by h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plastid
The plastid (Greek: πλαστός; plastós: formed, molded – plural plastids) is a membrane-bound organelle found in the Cell (biology), cells of plants, algae, and some other eukaryotic organisms. They are considered to be intracellular endosymbiotic cyanobacteria. Examples include chloroplasts (used for photosynthesis), chromoplasts (used for pigment synthesis and storage), and leucoplasts (non-pigmented plastids that can sometimes differentiate). The event which led to permanent endosymbiosis in the Archaeplastida clade (of Embryophyte, land plants, red algae, and green algae) probably occurred with a cyanobiont (a symbiotic cyanobacteria) related to the genus ''Gloeomargarita lithophora, Gloeomargarita'', around 1.5 billion years ago. A later primary endosymbiosis event occurred in photosynthetic ''Paulinella'' amoeboids about 90–140 million years ago. This plastid belongs to the "PS-clade" (of the cyanobacteria genera ''Prochlorococcus'' and ''Synechococcus''). Chloroplas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Algae
Algae (; singular alga ) is an informal term for a large and diverse group of photosynthetic eukaryotic organisms. It is a polyphyletic grouping that includes species from multiple distinct clades. Included organisms range from unicellular microalgae, such as ''Chlorella,'' ''Prototheca'' and the diatoms, to multicellular forms, such as the giant kelp, a large brown alga which may grow up to in length. Most are aquatic and autotrophic (they generate food internally) and lack many of the distinct cell and tissue types, such as stomata, xylem and phloem that are found in land plants. The largest and most complex marine algae are called seaweeds, while the most complex freshwater forms are the ''Charophyta'', a division of green algae which includes, for example, ''Spirogyra'' and stoneworts. No definition of algae is generally accepted. One definition is that algae "have chlorophyll ''a'' as their primary photosynthetic pigment and lack a sterile covering of cells around thei ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tetracycline
Tetracycline, sold under various brand names, is an oral antibiotic in the tetracyclines family of medications, used to treat a number of infections, including Acne vulgaris, acne, cholera, brucellosis, plague (disease), plague, malaria, and syphilis. Common side effects include vomiting, diarrhea, rash, and loss of appetite. Other side effects include poor tooth development if used by children less than eight years of age, kidney problems, and sunburning easily. Use during pregnancy may harm the baby. It works by inhibiting protein synthesis in bacteria. Tetracycline was patented in 1953 and came into commercial use in 1978. It is on the World Health Organization's List of Essential Medicines. Tetracycline is available as a generic medication. Tetracycline was originally made from bacteria of the genus ''Streptomyces''. Medical uses Spectrum of activity Tetracyclines have a broad spectrum of antibiotic action. Originally, they possessed some level of bacteriostatic acti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organelle
In cell biology, an organelle is a specialized subunit, usually within a cell, that has a specific function. The name ''organelle'' comes from the idea that these structures are parts of cells, as organs are to the body, hence ''organelle,'' the suffix ''-elle'' being a diminutive. Organelles are either separately enclosed within their own lipid bilayers (also called membrane-bound organelles) or are spatially distinct functional units without a surrounding lipid bilayer (non-membrane bound organelles). Although most organelles are functional units within cells, some function units that extend outside of cells are often termed organelles, such as cilia, the flagellum and archaellum, and the trichocyst. Organelles are identified by microscopy, and can also be purified by cell fractionation. There are many types of organelles, particularly in eukaryotic cells. They include structures that make up the endomembrane system (such as the nuclear envelope, endoplasmic reticulum, and G ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Endoplasmic-reticulum-associated Protein Degradation
Endoplasmic-reticulum-associated protein degradation (ERAD) designates a cellular pathway which targets misfolded proteins of the endoplasmic reticulum for ubiquitination and subsequent degradation by a protein-degrading complex, called the proteasome. Mechanism The process of ERAD can be divided into three steps: Recognition of misfolded or mutated proteins in the endoplasmic reticulum The recognition of misfolded or mutated proteins depends on the detection of substructures within proteins such as exposed hydrophobic regions, unpaired cysteine residues and immature glycans. In mammalian cells for example, there exists a mechanism called glycan processing. In this mechanism, the lectin-type chaperones calnexin/calreticulin (CNX/CRT) provide immature glycoproteins the opportunity to reach their native conformation. They can do this by way of reglucosylating these glycoproteins by an enzyme called UDP-glucose- glycoprotein glucosyltransferase also known as UGGT. Term ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Endosymbiosis
An ''endosymbiont'' or ''endobiont'' is any organism that lives within the body or cells of another organism most often, though not always, in a mutualistic relationship. (The term endosymbiosis is from the Greek: ἔνδον ''endon'' "within", σύν ''syn'' "together" and βίωσις ''biosis'' "living".) Examples are nitrogen-fixing bacteria (called rhizobia), which live in the root nodules of legumes, single-cell algae inside reef-building corals and bacterial endosymbionts that provide essential nutrients to insects. There are two types of symbiont transmissions. In horizontal transmission, each new generation acquires free living symbionts from the environment. An example is the nitrogen-fixing bacteria in certain plant roots. Vertical transmission takes place when the symbiont is transferred directly from parent to offspring. It is also possible for both to be involved in a mixed-mode transmission, where symbionts are transferred vertically for some generation befor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thylakoids
Thylakoids are membrane-bound compartments inside chloroplasts and cyanobacteria. They are the site of the light-dependent reactions of photosynthesis. Thylakoids consist of a thylakoid membrane surrounding a thylakoid lumen. Chloroplast thylakoids frequently form stacks of disks referred to as grana (singular: granum). Grana are connected by intergranal/stromal thylakoids, which join granum stacks together as a single functional compartment. In thylakoid membranes, chlorophyll pigments are found in packets called quantasomes. Each quantasome contains 230 to 250 chlorophyll molecules. Etymology The word ''Thylakoid'' comes from the Greek word ''thylakos'' or ''θύλακος'', meaning "sac" or "pouch". Thus, ''thylakoid'' means "sac-like" or "pouch-like". Structure Thylakoids are membrane-bound structures embedded in the chloroplast stroma. A stack of thylakoids is called a granum and resembles a stack of coins. Membrane The thylakoid membrane is the site of the li ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
