Answer
a.) Blunt ends are produced when a restriction enzyme cuts straight through the DNA such that it doesn't leave any overlapping region and so blunt ends cannot base pair with each other after restriction. In the given data the following enzymes produce blunt ends: Alul, EcoRV, Haelll, Pvull. Example: Alul : 5'-AG| CT-3' 3'-TC| GC-5' Here the cuts produced by the enzyme leave no overhanging nucleotides therefore they cannot base pair with each other.
b) The enzyme pairs that recognize and cut the same sequence are the ones that recognize either the exact same sequence or its reverse or it's complementary sequence: 1. Alul and Taql: both recognize AGCT TCGA 2. BamHI and EcoRII: GGATCC 3. Haelll, Hpall, Mspl: GGCC 4. Pvull, Sall, Xhol: CAGCTG
c) sticky ends are formed by restriction enzymes which make a staggered cut on two different sites on the DNA such that overlapping regions that can base pair are produced. The enzymes that leave identical sticky ends are: 1 Hpall and Mspl: 5'-C| CGG-3' 2. Pstl and Xhol: produce sticky ends that can easily base pair with each other. 5' CTGCA IC-3'
Work Step by Step
a.) Blunt ends are produced when a restriction enzyme cuts straight through the DNA such that it doesn't leave any overlapping region and so blunt ends cannot base pair with each other after restriction. In the given data the following enzymes produce blunt ends: Alul, EcoRV, Haelll, Pvull. Example: Alul : 5'-AG| CT-3' 3'-TC| GC-5' Here the cuts produced by the enzyme leave no overhanging nucleotides therefore they cannot base pair with each other.
b) The enzyme pairs that recognize and cut the same sequence are the ones that recognize either the exact same sequence or its reverse or it's complementary sequence: 1. Alul and Taql: both recognize AGCT TCGA 2. BamHI and EcoRII: GGATCC 3. Haelll, Hpall, Mspl: GGCC 4. Pvull, Sall, Xhol: CAGCTG
c) sticky ends are formed by restriction enzymes which make a staggered cut on two different sites on the DNA such that overlapping regions that can base pair are produced. The enzymes that leave identical sticky ends are: 1 Hpall and Mspl: 5'-C| CGG-3' 2. Pstl and Xhol: produce sticky ends that can easily base pair with each other. 5' CTGCA IC-3'
