Search results
Results from the WOW.Com Content Network
A hydroxide ion acting as a nucleophile in an S N 2 reaction, converting a haloalkane into an alcohol. In chemistry, a nucleophile is a chemical species that forms bonds by donating an electron pair. All molecules and ions with a free pair of electrons or at least one pi bond can act as nucleophiles. Because nucleophiles donate electrons, they ...
The RNA chain is synthesized from the 5' end to the 3' end as the 3'-hydroxyl group of the last ribonucleotide in the chain acts as a nucleophile and launches a hydrophilic attack on the 5'-triphosphate of the incoming ribonucleotide, releasing pyrophosphate as a by-[6] product. Due to the physical properties of the nucleotides, the backbone of ...
Cytosine (/ ˈ s aɪ t ə ˌ s iː n,-ˌ z iː n,-ˌ s ɪ n / [2] [3]) (symbol C or Cyt) is one of the four nucleotide bases found in DNA and RNA, along with adenine, guanine, and thymine (uracil in RNA).
These elements are all in the 16th periodic table column , so have similar properties. [53] [54] In each case, changing the nucleophile lowered the enzyme's protease activity, but increased a new activity. A sulfur nucleophile improved the enzymes transferase activity (sometimes called subtiligase).
Cysteine (symbol Cys or C; [5] / ˈ s ɪ s t ɪ iː n /) [6] is a semiessential [7] proteinogenic amino acid with the formula HOOC−CH(−NH 2)−CH 2 −SH.The thiol side chain in cysteine enables the formation of disulfide bonds, and often participates in enzymatic reactions as a nucleophile.
A few elements have been found to have a pharmacologic function in humans (and possibly in other living things as well; the phenomenon has not been widely studied). In these, a normally nonessential element can treat a disease (often a micronutrient deficiency). An example is fluorine, which reduces the effects of iron deficiency in rats.
In many cases they are able to mimic the mechanism used by their protein counterparts. For example, in self cleaving ribozyme RNAs, an in-line SN2 reaction is carried out using the 2’ hydroxyl group as a nucleophile attacking the bridging phosphate and causing 5’ oxygen of the N+1 base to act as a leaving group.
Element Per. Gr. Role(s) in nature (non-living and living) Role(s) in technology (old and new) 1: H: Hydrogen 1 1: Astronomy: source of power by nuclear fusion (proton–proton chain reaction and CNO cycle) Biology: One of the most common elements in living organisms: Petrochemical industry: hydrodealkylation, hydrodesulfurization