Nucleic acids

Nucleic acid:
The biopolymers of high molecular weight with mononucleotides as their repeating units Or linear polymers of nucleotides (polynucleotide).

History & Discovery:
• Nucleic acids were discovered by Swiss biochemist Friedrick Mischer in 1869 in Pus cells (WBC).
• He named it as “nuclein” (Phosphate rich substance).
• He continued his studies on Salmon sperms and isolated nuclein in pure (DNA without proteins) form in 1874 from Salmon sperm.
• As nuclein had acidic properties, it was named as “nucleic acid”, by Altman in 1899.
Note: DNA: 90% in nucleus and 10% is extranuclear. (Extranuclear DNA is present in mitochondria and cytoplasm). RNA: 90% is present in cytoplasm, while only 10% in nucleolus.

Elemental Composition:
i. Carbon
ii. Oxygen
iii. Hydrogen
iv. Nitrogen
v. Phosphorus

Types:
1. Deoxy ribo Nucleic acid (90% in nucleus)
2. Ribo nucleic acid (90% in cytoplasm)

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