To incorporate radiolabeled nucleotides into newly synthesized DNA, researchers use α-phosphorus32-labeled nucleotides, in a DNA synthesis reaction, where the α denotes the position of the radioactive phosphate moiety. Explain why the α position--rather than the β or γ positions--is the best position for the radioactive group in these experiments.
DNA polymerase acts on a 3'OH for nucleophilic attack on the one
of the phosphate attached to the 5' carbon on another nucleotide
subunit.
3'OH shows nucleophilic attack on triphosphate group which is on
the 5' carbon that makes us understand why researchers use
α-phosphorus32-labeled nucleotides.
Phosphate bonds are high energy therefore when the 3'OH has its
nucleophilic attack then it will not attack phosphates in the β or
γ positions as they are not energetically favorable.
It will attack the phosphate in the α position which is is closest
to the 5' carbon.
When DNA is synthesized then β and γ phosphates cleaved and α
phosphate bonds form polymer with the 3'OH.
So we conclude, α position is the only phosphate that is
incorporated into the newly synthesized DNA molecule....
To incorporate radiolabeled nucleotides into newly synthesized DNA, researchers use α-phosphorus32-labeled nucleotides, in a DNA synthesis...
Dideoxy nucleotides that are used in DNA sequencing experiments terminate DNA synthesis because they: cannot be recognized by DNA polymerases and therefore are not incorporated during synthesis. have no 3′ -OH group and so no additional nucleotides can be added after these nucleotides are incorporated. have no phosphate groups. are only recognized by reverse transcriptases. have methyl groups attached to the 5′ position of the sugar and cannot be incorporated during synthesis.
When enzymes are elongating (building) a newly synthesized DNA strand in PCR, new nucleotides are being added to the_of the growing strand. A 5 phosphate group B. A nitrogenous base C. 3' hydroxyl of deoxyribose D. 2 H of deoxyribose
Please need help answering question A the pages of background information are posted thanks Read page 196-197 and figure 6.20. regarding Meselson and Stahl’s experiment regarding DNA replication. And Answer the following question If you are using this radioactive technique in mouse cells, what would happen in each phase of G1, S, G2, mitosis and meiosis assuming that you are grown cells in 15N medium for many generations and cells in G1are then switched to 14N medium? G1 S G2...