Nucleic acid Flashcards
What are the 4 bases in DNA?
Adenine
Thymine
Cytosine
Guanine
What are the 4 bases in RNA?
Adenine
Uracil
Cytosine
Guanine
Which two bases are the purines?
Adenine
Guanine
Which bases are pyridines?
Uracil
Thymine
Cytosine
What is the difference between uracil and thymine?
Thymine has a methyl group which uracil does not
Where does the sugar join to the purines?
At the 5 membered ring
What is the sugar called in RNA?
β-D-Ribofuranose
What is the sugar called in DNA?
2-Deoxy-β-D-ribofuranose
Where is the oxygen lost in β-D-Ribofuranose to become 2-Deoxy-β-D-ribofuranose?
2- position
What is a nucleoside?
The base and sugar
Where does the bond form between the base and the sugar in a nucleoside?
At the 1 position
What is the name of adenine + sugar in RNA?
Adenosine
What is the sugar called in DNA?
2-Deoxy-β-D-ribofuranose
What is the name of uracil + sugar in RNA?
Uridine
What is the name of cytosine + sugar in RNA?
Cytidine
What is the name of adenine and sugar in DNA?
2-deoxyadenosine
What is the name of thymine and sugar in DNA?
2-deoxythymidine
How do you name nucleosides?
β-N1-Glycosidic bond
What is a nucleotide?
Nucleoside + phosphate
Which positions can phosphate join?
2’
3’
5’
Which position is phosphate usually joined at?
5’ - OH position
What types of phosphates can form?
mono-
di-
tri-
What is the name of cytosine and sugar in DNA?
2-deoxycytidine
What is the name of guanine and sugar in DNA?
2-deoxyguanosine
What is the full name of the nucleotide with the adenine base in DNA with one phosphate?
2’-Deoxyadenosine 5’-monophosphate
What is the short hand for 2’-Deoxyadenosine 5’-monophosphate?
dAMP
What is the full name of the nucleotide with the guanine base in DNA with one phosphate?
2’-Deoxyguanosine 5’-monophosphate
What is the full name of the nucleotide with the thymine base in DNA with one phosphate?
2’-Deoxythymidine 5’-monophosphate
What is the shorthand for 2’-Deoxyguanosine 5’-monophosphate?
dGMP
What is the shorthand for 2’-Deoxythymidine 5’-monophosphate?
dTMP
What is the full name of the nucleotide with the cytosine base in DNA with one phosphate?
2’-Deoxycytidine 5’-monophosphate
What is the shorthand for 2’-Deoxycytidine 5’-monophosphate?
dCMP
Which direction is the strand read?
5’ to 3’
In the phosphodiester backbone, where does the phosphate group link to?
The 3’-OH of one sugar to the 5’-OH of the next
What is the general structure of DNA?
Double stranded with a double helix structure
What is the diameter of the double helix?
2.37 nM
What is the distance between base pairs?
0.33 nM
What is the pitch of a double helix (How far up one turn is)?
3.40 nM
How many base pairs are there per complete turn?
10.4
How many hydrogen bonds between adenine and thymine?
2
How many hydrogen bonds between cytosine and guanine?
3
What types of bond pairs are between the bases?
Hydrogen bonds
What are the 4 types of interactions which stabilise the double helix structure?
Stacking interactions
Hydrogen bonds
Hydrophobic effects
Charge-charge interactions
How do stacking interactions stabilise the double helix structure?
Causes van der waal forces between base pairs
Bases are aromatic structures which means there are pi clouds that are close together
How do the hydrophobic effects stabilise the double helix structure?
The hydrophobic purines and pyrimidines are buried within the helix and this increases stability
How do charge-charge interactions stabilise the double helix structure?
The electrostatic repulsion of the negatively charged phosphates is minimised by the presence of ions
What structure does RNA form?
Usually single stranded but can form double helices including a hairpin loop
What can RNA do with DNA?
Hybridise with it to form G-C, A-T and U-A base pairs