Which are the 3 components of RNA nucleotide? Types of bonds in a RNA nucleotide.

RNA (ribo nucleic acid) is single stranded made of ribonucleotides.  mRNA acts as a messenger between DNA and protein during protein synthesis. The major constituent of ribosome is rRNA which is involved in protein synthesis. tRNA functions as an adaptor molecule aligning correct amino acids in the peptide chain during protein synthesis.  

Russian biochemist Phoebus Levene discovered the order of the three major components of a single nucleotide both DNA and RNA (phosphate-sugar-base)

Sugar and phosphate forms the backbone of RNA

3 components of RNA nucleotide
The 3 components of RNA nucleotide

1. Phosphate group

2. Pentose Sugar molecule (ribose in RNA)

3. Nitrogen-containing base.

1. Phosphate group

A free, unincorporated nucleotide contains a chain of three phosphates (triphosphosphates). During formation of RNA strand, it loses two of these phosphate groups, so that only one phosphate is incorporated the RNA strand. The negative charge of RNA is due to the phosphate group that contains one negatively charged oxygen atom. 

2.  Pentose Sugar molecule (ribose in RNA)

The sugar in RNA is ribose. In ribose, the 2nd C position of ribose sugar has OH group unlike H atom in deoxy ribose.

3. Nitrogen-containing base.

The 4 bases used in RNA are adenine (A), cytosine (C), guanine (G), and uracil (U).

Adenine and Guanine are two ringed (nine-member double ring) and forms the purines

Cytosine (C) and Uracil (U) are single ringed (six-member single ring) and forms the pyrimidines

In RNA; in the place of thymine there is uracil.

This is the summarized video on ribonucleotide

Bonds within RNA nucleotide or ribonucleotide

Glycosidic bond

 Pentose Sugar and nitrogenous base joined by glycosidic bond forms ribonucleoside

Glycosidic bond (nitrogen-carbon linkage) between C1 of sugar-N9 of purine bases (C1-N9 glycosidic bond) (Adenine and Guanine)

Carbon 1 of sugar and nitrogen 1 of pyrimidine bases (C1-N1 glycosidic  bond)(Cytosine and uracil)

Ester bond in a Nucleotide

Ribonucloside+phosphate =ribonucleotide

Ester bond formed within nucleotide between 5th Carbon of sugar and phosphate.

Sugar reacts with phosphate forming an ester –C-O-bond with release of H2O

These are the bonds within a nucleotide

Now between adjacent nucleotides in a RNA strand; phosphate is the connecting link.

-C-O bond is called the ester bond.

Two Ester bonds connect the adjacent ribonucleotide via phosphate. Therefore; called as phosphodiester bond.

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