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Caffeine Synthase
Caffeine synthase is a methyltransferase enzyme involved in the caffeine biosynthesis pathway. It is expressed in tea species, coffee species, and cocoa species. The enzyme catalyses the following reactions: * ''S''-adenosyl-L-methionine + theobromine \rightleftharpoons ''S''-adenosyl-L-homocysteine + caffeine + H+ * ''S''-adenosyl-L-methionine + paraxanthine \rightleftharpoons ''S''-adenosyl-L-homocysteine + caffeine + H+ * 7-methylxanthine + ''S''-adenosyl-L-methionine \rightleftharpoons ''S''-adenosyl-L-homocysteine + H+ + theobromine Caffeine synthase is expressed in the ''Camellia'' species '' irrawadiensis'', '' ptilophylla'', and '' sinensis''; the '' Coffea'' species '' arabica'', and ''canephora''; and in ''Theobroma cacao ''Theobroma cacao'', also called the cacao tree and the cocoa tree, is a small ( tall) evergreen tree in the family Malvaceae. Its seeds, cocoa beans, are used to make chocolate liquor, cocoa solids, cocoa butter and chocolate. The largest ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methyltransferase
Methyltransferases are a large group of enzymes that all methylate their substrates but can be split into several subclasses based on their structural features. The most common class of methyltransferases is class I, all of which contain a Rossmann fold for binding ''S''-Adenosyl methionine (SAM). Class II methyltransferases contain a SET domain, which are exemplified by SET domain histone methyltransferases, and class III methyltransferases, which are membrane associated. Methyltransferases can also be grouped as different types utilizing different substrates in methyl transfer reactions. These types include protein methyltransferases, DNA/RNA methyltransferases, natural product methyltransferases, and non-SAM dependent methyltransferases. SAM is the classical methyl donor for methyltransferases, however, examples of other methyl donors are seen in nature. The general mechanism for methyl transfer is a SN2-like nucleophilic attack where the methionine sulfur serves as the leavi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Camellia
''Camellia'' (pronounced or ) is a genus of flowering plants in the family Theaceae. They are found in eastern and southern Asia, from the Himalayas east to Japan and Indonesia. There are more than 220 described species, with some controversy over the exact number, and also around 3,000 hybrids. The genus was named by Linnaeus after the Jesuit botanist Georg Joseph Kamel, who worked in the Philippines and described a species of camellia (although Linnaeus did not refer to Kamel's account when discussing the genus). Of economic importance in East Asia, Southeast Asia, and the Indian subcontinent, leaves of '' C. sinensis'' are processed to create the popular beverage tea. The ornamental '' C. japonica'', '' C. sasanqua'' and their hybrids are the source of hundreds of garden cultivars. '' C. oleifera'' produces tea seed oil, used in cooking and cosmetics. Descriptions Camellias are evergreen shrubs or small trees up to tall. Their leaves are alternately arranged, simple, t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Theobroma Cacao
''Theobroma cacao'', also called the cacao tree and the cocoa tree, is a small ( tall) evergreen tree in the family Malvaceae. Its seeds, cocoa beans, are used to make chocolate liquor, cocoa solids, cocoa butter and chocolate. The largest producer of cocoa beans in 2018 was Ivory Coast, 2.2 million tons. Description Its leaves are alternate, entire, unlobed, long and broad. Flowers The flowers are produced in clusters directly on the trunk and older branches; this is known as cauliflory. The flowers are small, diameter, with pink calyx. The floral formula, used to represent the structure of a flower using numbers, is ✶ K5 C5 A(5°+52) (5). While many of the world's flowers are pollinated by bees ( Hymenoptera) or butterflies/moths ( Lepidoptera), cacao flowers are pollinated by tiny flies, ''Forcipomyia'' midges in the subfamily Forcipomyiinae. Using the natural pollinator ''Forcipomyia'' midges for ''Theobroma cacao'' was shown to have more fruit production th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coffea Canephora
''Coffea canephora'' ( syn. ''Coffea robusta'', commonly known as ''robusta coffee'') is a species of coffee that has its origins in central and western sub-Saharan Africa. It is a species of flowering plant in the family Rubiaceae. Though widely known as ''Coffea robusta'', the plant is scientifically identified as ''Coffea canephora'', which has two main varieties, ''robusta'' and '' nganda''. ''Coffea robusta'' represents 43% of global coffee production, with '' Coffea arabica'' constituting most of the remainder. There are several differences between the composition of coffee beans from ''C. arabica'' and ''C. robusta''. Beans from ''C. robusta'' tend to have lower acidity, more bitterness, and a more woody and less fruity flavor compared to ''C. arabica'' beans. Description Robusta is a species of flowering plant in the family Rubiaceae. Though widely known by the synonym ''Coffea robusta'', the plant is currently scientifically identified as ''Coffea canephora'', whic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coffea Arabica
''Coffea arabica'' (), also known as the Arabic coffee, is a species of flowering plant in the coffee and madder family Rubiaceae. It is believed to be the first species of coffee to have been cultivated and is currently the dominant cultivar, representing about 60% of global production. Coffee produced from the less acidic, more bitter, and more highly caffeinated robusta bean ('' C. canephora'') makes up most of the remaining coffee production. Arabica coffee originates from and was first cultivated in Yemen, and documented by the 12th century. ''Coffea arabica'' is called () in Arabic, borrowed from the Amharic "Buna". Taxonomy ''Coffea arabica'' was first described scientifically by Antoine de Jussieu, who named it ''Jasminum arabicum'' after studying a specimen from the Botanic Gardens of Amsterdam. Linnaeus placed it in its own genus ''Coffea'' in 1737. ''Coffea arabica'' is the only polyploid species of the genus ''Coffea,'' as it carries 4 copies of the 11 chromosom ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coffea
''Coffea'' is a genus of flowering plants in the Family (biology), family Rubiaceae. ''Coffea'' species are shrubs or small trees native to tropical and southern Africa and tropical Asia. The seeds of some species, called coffee beans, are used to flavor various beverages and products. The fruits, like the seeds, contain a large amount of caffeine, and have a distinct sweet taste and are often juiced. The plant ranks as one of the world's most valuable and widely traded commodity crops and is an important export product of several countries, including those in Central and South America, the Caribbean and Africa. Cultivation and use There are over 120 species of ''Coffea'', which is grown from seed. The two most popular are ''Coffea arabica'' (commonly known simply as "Arabica"), which accounts for 60–80% of the world's coffee production, and ''Coffea canephora'' (known as "Robusta coffee, Robusta"), which accounts for about 20–40%. '' C. arabica'' is preferred for its s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Camellia Sinensis
''Camellia sinensis'' is a species of evergreen shrub or small tree in the flowering plant family Theaceae. Its leaves and leaf buds are used to produce the popular beverage, tea. Common names include tea plant, tea shrub, and tea tree (not to be confused with ''Melaleuca alternifolia'', the source of tea tree oil, or the genus ''Leptospermum'' commonly called tea tree). White tea, yellow tea, green tea, oolong, dark tea (which includes pu-erh tea) and black tea are all harvested from one of two major varieties grown today, ''C. sinensis'' var. ''sinensis'' and ''C. s.'' var. ''assamica'', but are processed differently to attain varying levels of oxidation with black tea being the most oxidized and green being the least. Kukicha (twig tea) is also harvested from ''C. sinensis'', but uses twigs and stems rather than leaves. Nomenclature and taxonomy The generic name ''Camellia'' is taken from the Latinized name of Rev. Georg Kamel, SJ (1661–1706), a Moravian-born Jesuit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Camellia Ptilophylla
''Camellia ptilophylla'', also called the cocoa tea plant (not to be confused with the chocolate plant ''Theobroma cacao''), is a species of ''Camellia'' plant found in Southern Asia. It has insignificant levels of naturally occurring caffeine, unlike other varieties of the plant used to make tea. History For many years, it has been widely consumed by local inhabitants in the Longmen area of Guangdong Province of China but has only started attracting scientific interest since 1988. It was first scientifically documented in the 1980s. Preparation for tea A recommendation for consuming cocoa tea is like steeping most other teas, in which to infuse tea leaves with boiling water for 3 min. The aroma profile of Cocoa tea is different from the traditional green tea, but the difference between oolong Cocoa tea and traditional oolong tea is not. For instance, fruity, white peach-like and floral, orchid-like and dry-fruit were stronger in the Cocoa tea infusion, while roasted, fresh tre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Camellia Irrawadiensis
''Camellia'' (pronounced or ) is a genus of flowering plants in the family Theaceae. They are found in eastern and southern Asia, from the Himalayas east to Japan and Indonesia. There are more than 220 described species, with some controversy over the exact number, and also around 3,000 hybrids. The genus was named by Linnaeus after the Jesuit botanist Georg Joseph Kamel, who worked in the Philippines and described a species of camellia (although Linnaeus did not refer to Kamel's account when discussing the genus). Of economic importance in East Asia, Southeast Asia, and the Indian subcontinent, leaves of '' C. sinensis'' are processed to create the popular beverage tea. The ornamental '' C. japonica'', '' C. sasanqua'' and their hybrids are the source of hundreds of garden cultivars. '' C. oleifera'' produces tea seed oil, used in cooking and cosmetics. Descriptions Camellias are evergreen shrubs or small trees up to tall. Their leaves are alternately arranged, simp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Caffeine
Caffeine is a central nervous system (CNS) stimulant of the methylxanthine class. It is mainly used recreationally as a cognitive enhancer, increasing alertness and attentional performance. Caffeine acts by blocking binding of adenosine to the adenosine A1 receptor, which enhances release of the neurotransmitter acetylcholine. Caffeine has a three-dimensional structure similar to that of adenosine, which allows it to bind and block its receptors. Caffeine also increases cyclic AMP levels through nonselective inhibition of phosphodiesterase. Caffeine is a bitter, white crystalline purine, a methylxanthine alkaloid, and is chemically related to the adenine and guanine bases of deoxyribonucleic acid (DNA) and ribonucleic acid (RNA). It is found in the seeds, fruits, nuts, or leaves of a number of plants native to Africa, East Asia and South America, and helps to protect them against herbivores and from competition by preventing the germination of nearby seeds, as well as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
