Search results
Results From The WOW.Com Content Network
In organic chemistry, endo–exo isomerism is a special type of stereoisomerism found in organic compounds with a substituent on a bridged ring system. [1] The prefix endo is reserved for the isomer with the substituent located closest, or " syn ", to the longest bridge.
Chemical structure of an LNA monomer an additional bridge bonds the 2' oxygen and the 4' carbon of the pentose. A locked nucleic acid (LNA), also known as bridged nucleic acid (BNA), [1] and often referred to as inaccessible RNA, is a modified RNA nucleotide in which the ribose moiety is modified with an extra bridge connecting the 2' oxygen and 4' carbon.
Its favored conformation is at low water concentrations. A-DNAs base pairs are tilted relative to the helix axis, and are displaced from the axis. The sugar pucker occurs at the C3'-endo and in RNA 2'-OH inhibits C2'-endo conformation. [13] Long considered little more than a laboratory artifice, A-DNA is now known to have several biological ...
into exo and endo ring closures, depending whether the bond broken during the ring closure is inside (endo) or outside (exo) the ring that is being formed into tet , trig and dig geometry of the atom being attacked, depending on whether this electrophilic carbon is tet rahedral ( sp 3 hybridised ), trig onal ( sp 2 hybridised ) or diag onal ...
Class I AP endonucleases (EC 4.2.99.18) cleave 3′ to AP sites by a β-lyase mechanism, leaving an unsaturated aldehyde, termed a 3′-(4-hydroxy-5-phospho-2-pentenal) residue, and a 5′-phosphate. Class II AP endonucleases incise DNA 5′ to AP sites by a hydrolytic mechanism, leaving a 3′-hydroxyl and a 5′-deoxyribose phosphate residue. [2]
Oxidation of (+)-isoserine (3) by nitrous acid gives (−)-glyceric acid, establishing that (+)-isoserine also has the same absolute configuration. [ 6 ] (+)-Isoserine can be converted by a two-stage process of bromination to (−)-3-bromo-2-hydroxy-propanoic acid ( 4 ) and zinc reduction to give (−)- lactic acid ( 5 ), therefore (−)-lactic ...
The AP endonuclease recognizes this sugar and essentially cuts the DNA at this site and then allows for DNA repair to continue. [10] E. coli cells contain two AP endonucleases: endonuclease IV (endoIV) and exonuclease III (exoIII) while in eukaryotes, there is only one AP endonuclease. [11]
The H motif is located in the hinge and the ACA motif is located in the tail region; 3 nucleotides from the 3′ end of the sequence. [11] The hairpin regions contain internal bulges known as recognition loops in which the antisense guide sequences (bases complementary to the target sequence) are located.