112:. The G-quadruplex can either be parallel or antiparallel depending on the loop configuration, which is a component of the structure. If all the DNA strands run in the same direction, it is termed to be a parallel quadruplex, and is known as a strand-reversal/propeller, connecting adjacent parallel strands. If one or more of the DNA strands run in opposite direction, it is termed as an anti-parallel quadruplex, and can either be in a form of a lateral/edgewise, connecting adjacent anti-parallel strands, or a diagonal, joining two diagonally opposite strands. The structure of these G-quadruplexes can be determined by a cation.
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because it replicates the leading strand one way and the lagging strand the other way. During DNA replication, the leading strand is replicated continuously whereas the lagging strand is replicated in segments known as
264:. Beta sheets can also be either a parallel or anti-parallel secondary structure. However, an anti-parallel beta sheet is significantly more stable than a parallel structure due to their well aligned
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would be another problem if the DNA structure were to be parallel, making no sense of the information being read from the DNA. This would further lead to the production of incorrect proteins.
166:. If the DNA structure were to be parallel, the hydrogen bonding would not be possible, as the base pairs would not be paired in the known way. The four base pairs are:
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are complementary and parallel, but they go in opposite directions, hence the antiparallel designation. The antiparallel structure of DNA is important in
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The importance of an antiparallel DNA double helix structure is because of its hydrogen bonding between the complementary
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256:. In beta sheets, sections of a single polypeptide may run side-by-side and antiparallel to each other, to allow for
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287:"A G-quadruplex DNA-affinity Approach for Purification of Enzymatically Active G4 Resolvase1"
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100:, also known as G4 DNA are secondary structures found in nucleic acids that are rich in
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The different types of topologies in G-quadruplex, propeller, lateral, and diagonal.
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Routh ED, Creacy SD, Beerbower PE, Akman SA, Vaughn JP, Smaldino PJ (March 2017).
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Burge S, Parkinson GN, Hazel P, Todd AK, Neidle S (2017-04-01).
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412:"Re: Why are the two strands of a DNA molecule antiparallel?"
77:, and can be used to define the movement of enzymes such as
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relative to the DNA strand in a non-arbitrary manner.
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332:"Quadruplex DNA: sequence, topology and structure"
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104:. These structures are normally located at the
436:"why is DNA antiparallel? Can it be parallel?"
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228:can be represented as its set of unique
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232:within an N-terminus and a C-terminus.
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73:(3') end. This notation follows from
244:Antiparallel and parallel beta sheet
39:(alignments). An example is the two
387:. Boston University. Archived from
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224:notation in polypeptides; a given
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460:"Secondary structure of Proteins"
291:Journal of Visualized Experiments
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155:Anti-parallelism in biochemistry
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35:to each other but with opposite
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75:organic chemistry nomenclature
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130:is located at the top of the
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248:Many proteins may adopt a
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52:run in opposite directions
440:biology.stackexchange.com
230:amino acid abbreviations
464:www.chembio.uoguelph.ca
410:PhD, Kenneth P Mitton.
381:"Anti-Parallel Strands"
336:Nucleic Acids Research
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140:nucleic acid sequences
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54:alongside each other.
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16:Term in biochemistry
254:secondary structure
391:on 22 October 2019
385:K*Nex DNA Modeling
348:10.1093/nar/gkl655
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252:as part of their
220:is the basis for
213:sequence of each
149:Okazaki fragments
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65:molecules have a
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342:(19): 5402–15.
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262:backbone chains
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144:DNA replication
126:In DNA, the 5'
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122:DNA Replication
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116:DNA replication
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79:DNA polymerases
69:(5') end and a
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222:directionality
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136:lagging strand
132:leading strand
120:Main article:
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98:G-quadruplexes
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85:G-quadruplexes
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37:directionality
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184:Transcription
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58:Nucleic acids
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43:strands of a
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495:Biochemistry
472:. Retrieved
468:the original
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393:. Retrieved
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195:Polypeptides
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190:Polypeptides
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110:chromosomes)
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63:Nucleic acid
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48:double helix
31:if they run
29:antiparallel
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21:biochemistry
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395:12 December
207:synthesized
161:nitrogenous
25:biopolymers
474:2017-04-01
445:2017-04-06
421:2017-04-06
379:Benson G.
272:References
250:beta sheet
236:Beta sheet
215:amino acid
203:C-terminus
199:N-terminus
164:base pairs
67:phosphoryl
106:telomeres
489:Category
366:17012276
317:28362374
218:sub-unit
197:have an
176:cytosine
71:hydroxyl
50:, which
33:parallel
357:1636468
308:5409278
266:H-bonds
226:protein
180:thymine
172:guanine
168:adenine
102:guanine
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209:. The
201:and a
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138:. The
128:carbon
23:, two
397:2011
362:PMID
313:PMID
27:are
352:PMC
344:doi
303:PMC
295:doi
45:DNA
19:In
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Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.
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