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核酸s such as脱氧核糖核酸和RNAare聚合物s of monomericnucleotides. Each nucleotide is made up of phosphoric acid, sugar (5-carbon), and nitrogenous base (or nucleobase). There are fivenucleobase作为遗传密码的基本单位的S：（1）腺嘌呤, (2)鸟鸣（3）cytosine（4）胸腺嘧啶， 和(5)尿嘧啶。These nitrogenous bases may be classified intopurine沙嘧啶.s.
腺嘌呤是一种嘌呤核碱基，具有C的化学式5H5N5。Purines are heterocyclic aromatic organic compounds. As a purine, adenine is comprised of two carbon rings: a嘧啶.ring和咪唑戒指。When it is a constituent of DNA, it is linked to the deoxyribose sugar by a covalent bond, and is referred to as腺嘌呤残留。
腺嘌呤, similar to guanine, is derived from the nucleotide肌苷单磷酸盐(IMP) since purines are synthesized as ribonucleotides and not as free nucleobases. IMP, in turn, is produced from a pre-existing磷酸核糖这主要来自氨基酸glycine,glutamine， 和aspartic acid。Ribose 5-phosphate reacts with ATP to produce5-Phosphoribosyl-1-pyrophosphate(PRPP). PRRP has a role in both purine and pyrimidine synthesis; it is also involved in NAD and NADP formation and salvage pathways. PRRP though becomes committed particularly to purine biosynthesis when PRRP is converted into5-phosphoribosyl amineby having the pyrophosphate of PRRP replaced by the amide group of glutamine. In humans, the biosynthesis of purines occurs in the cytosol of the liver cell. IMP is then converted into eitheradenosine monophosphate(AMP) or鸟苷一起(GMP). Guanosine triphosphate (GTP) provides energy for the conversion of IMP to AMP.
腺苷和deoxyadenosine是核苷s of adenine. The adenosine (i.e. an adenine bound to a ribose sugar) that is phosphorylated with three phosphoric acid groups becomesadenosine triphosphate（ATP）。ATP是能量丰富的分子，其作为各种代谢活动的能源。产生ATP的一些方式是糖酵解,Krebs cycle， 和fermentation。Other forms of energy-rich molecules with adenine as constituent are the cofactors烟酰胺腺嘌呤二核苷酸(NAD) and黄素腺嘌呤二核苷酸（FAD）。除此之外，ATP还用作构建RNA分子的核苷酸单体单元之一。用三个磷酸基团磷酸化的脱氧腺苷（即，与脱氧糖结合的腺嘌呤）成为脱氧腺苷三磷酸（DATP），其中一个核苷酸，其构建DNA分子。
腺嘌呤降解如下：腺苷»»inoosine（通过酶purine nucleoside phosphorylase）»缺氧（通过酶）xanthine oxidase) » xanthine (via the enzymexanthine oxidase) »uric acid。在人类和其他脊椎动物中，肝脏和鸟嘌呤如腺嘌呤和鸟嘌呤的外源嘌呤在肝脏中降解。由于嘌呤降解，尿酸作为废物制造。尿酸从肝脏释放到血液中，通过它到达肾脏。然后通过尿液从身体排出。来自分解代谢的腺嘌呤可以被酶的催化活性重新使用并重新使用腺嘌呤磷酰基转移酶。
腺嘌呤is one of the five primary (or canonical) nucleobases; the others are guanine, cytosine, thymine, and uracil. They are the fundamental nucleobases that make up the genetic code. Nucleic acids such as DNA and RNA molecules contain the genetic code for a particular protein based on the sequence of nucleobases. Nucleic acids hold an important role in cellular functions, heredity, and survival of an organism.
Apart from being a major component of nucleic acids, adenine is also a vital constituent of adenosine triphosphate (ATP), which is adenosine with three phosphate groups attached to it. ATP is an energy-rich molecule and is used in cellular metabolism and other biological reactions.
Uric acid is the metabolic end product of purine metabolism, including adenine. In the diet, purines are found in high amounts in liver, kidney, and other internal organs. They are also present in meat, seafood, cauliflower, beans, and mushrooms but in moderate amounts. Hyperuricemia is the condition when there is too much uric acid level in the body. Too much uric acid from a high-purine diet could eventually lead to gout (inflammation in the joint) and kidney stones. Thus, people with such conditions are advised to eat a rather low-purine diet. It is also further advised to restrain from, or avoid consuming, alcohol and saturated fats because they obstruct the proper metabolism of purines.
腺嘌呤以前被认为是维生素B复合物之一，特别是称为“维生素B.4。2However, it is no longer considered a vitamin because it can be biosynthesized by the body.
- Germanadenin，来自古希腊语ἀΔήν.(adḗn.:“杯子nd”) + –ine.
- The Editors of Encyclopedia Britannica. (2018). Albrecht Kossel German biochemist. In Encyclopædia Britannica. Retrieved fromhttps://www.britannica.com/biography/Albrecht-Kossel
- 读者，五。（1930）。“维生素B（4）的测定。生物化学杂志，24（6）：1827-31。DOI：10.1042 / BJ0241827。
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