Restriction Enzymes Overview

Recognise specific sequences within a DNA molecule (often 4-6 base pairs long) and cut them in a specific manner.

To destroy foreign DNA entering the cell by cleaving the bacteriophage DNA to prevent infection.

Recognise a specific DNA sequence (often 4 to 6 nucleotides in length) and cut precisely or near this site.

<p>EcoRI from E.coli (GAATTC, sticky), BamHI from Bacillus amyloliquefaciens (GGATCC, sticky), AluI from Arthrobacter luteus (AGCT, blunt), Sau3A from Staphylococcus aureus (GATC, sticky).</p> Signup and view all the answers

<p>When restriction enzymes cut straight across the double-stranded DNA.</p> Signup and view all the answers

<p>When restriction enzymes cut in a staggered fashion across its recognition site.</p> Signup and view all the answers

<p>They recognise different sites but produce the same sticky ends.</p> Signup and view all the answers

<p>A tetranucleotide is found once every $4^4$ times, and a hexanucleotide is found once every $4^6$ times.</p> Signup and view all the answers

<p>The reaction is carried out in a microfuge tube usually at 37°C for 1 hour with sterile components.</p> Signup and view all the answers

<p>A technique used to separate DNA molecules by mixing agarose with a buffer, heating, and cooling it to form a gel matrix.</p> Signup and view all the answers

<p>Agarose and buffer are heated, ethidium bromide added, poured onto a glass plate, and DNA is loaded into wells for separation.</p> Signup and view all the answers

<p>DNA fragments need to be stained with ethidium bromide either during or after electrophoresis.</p> Signup and view all the answers

<p>Fragments of known molecular weight are run on the gel to determine the size of unknown fragments.</p> Signup and view all the answers

<p>A method to determine the relative proportions of restriction sites for particular enzymes in a DNA molecule.</p> Signup and view all the answers