Nucleic Acids Flashcards
Who first isolated DNA and what was it called
Friedrich Miescher; called it nuclein
Nucleic acids are linear ______________ made by connecting nucleotides via ________________________ bonds
polymers; phosphodiester
What are the components of a nucleotide
sugar, base, phosphate group
The sugar and phosphates form a _________________ for the bases
backbone (sugar phosphate backbone)
RNA contains… (type of sugar)
D-ribose
DNA contains… (type of sugar)
D-2-deoxyribose
DNA and RNA sugars are in the _________________ form
b-furanose
What are the pyrimidines
cytosine and thymine (replaced with uracil in RNA)
What are the purines
adenine and guanine
Why are purines and pyrimidines considered heterocycles
they contain non-carbon atoms in their rings (nitrogen)
The purines are _______________ rings (think how many rings)
bicyclic (2 rings)
What are tautomeric forms
the shifting of one H atom to give the molecule a new form
What does the OH group undergo in tautomeric shifting
keto/enol tautomerism
What does the NH2 group undergo in tautomeric shifting
amino/imino tautomerism
What is the shift from enol to keto
-OH to =O
What is the shift from amino to imino
-NH2 to =NH
Base + Sugar (no phosphate) =
nucleoside
Base + sugar + phosphate =
nucleotide
What is the special type of glycoside found in nucleic acids
nucleoside
The glycosidic bond in nucleosides is also sometimes called the ______________ bond to account for the C-N linkage
glycosilic
The NH at position ______ of purines link to the anomeric carbon of ribose/deoxyribose
9
The NH at position ______ of pyrimidines link to the anomeric carbon of ribose/deoxyribose
1
Nucleotides are just ________________ nuceleosides
phosphorylated
A phosphate group bridges between the _______ OH of one nucleotide unit, and the _________ OH of another, forming a ___________________ linkage
between 5’ OH and 3’ OH
creating a phosphodiester linkage
What are the 5’ and 3’ ends lacking
nucleotides
5’ end lacks a nucleotide at 5’ position
3’ end lacks a nucleotide at 3’ position
The phosphate groups are _____________ and ______________ charged at pH 7
ionized and negatively charged
Under alkaline conditions, what happens in relation to RNA hybridization
the 2’ OH group reacts with the phosphate on the 3’ breaking the phosphodiester linkage
