The Denaturation of DNA

The Denaturation of DNA - Absorbance ability of a substance...

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
The Denaturation of DNA The two DNA strands are held together by base pairing (hydrogen bonding) between complementary bases. Cumulative effect of all of the hydrogen bonds is pretty strong, but only a little stronger than energy of thermal motion at RT. At elevated temperatures, the 3D structure of both proteins and nucleic acids (or any strucuture held together by H bonding) is disrupted. denaturation - disordered 3D structure, disrupted due to broken H bonds native - ordered 3D state, presumably as in biological systems. Native DNA is double-stranded DNA Upon heating double-stranded DNA------------------> single stranded DNA
Background image of page 1
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: Absorbance- ability of a substance to absorb light Visible light 400-700 nm DNA absorbs maximally at 260 nm (in the UV range) Proteins absorb maximally at 280 nm The ability of DNA to absorb light (260nm, UV) increases as denaturation progresses. Absorbance is primarily a property of the nitrogenous bases. When they are hydrogen bonded and in close proximity they cannot absorb light as well as when they are exposed. Absorbance goes up at 260nm even higher when the DNA is completely hydrolysed (broken down into single nulcleotides)....
View Full Document

This document was uploaded on 11/03/2011 for the course BIOLOGY MCB2010 at Broward College.

Ask a homework question - tutors are online