Phosphodiester linkages: repeating, sugar-phosphate backbone of the polynucleotide chain CH 3 N一HNA CH HO 2 G-H DNN C CH? CH2 CH2 N CH? H… cN…HNG CH2 3 DNA polarity: is defined by the asymmetry of the 5.nucleotides and the way they are joined
DNA polarity: is defined by the asymmetry of the nucleotides and the way they are joined. Phosphodiester linkages: repeating, sugar-phosphate backbone of the polynucleotide chain
adenine NH Bases in dna H pure Adenine(a) purines 9 Guanine) cytosine NH yrimidine Cytosine(C)∵ H H pyrimidines thymine Thymine(t) 004 Pearson Education, Inc, publishing as benjar
Bases in DNA purines pyrimidines Adenine (A) Guanine (G) Cytosine (C) Thymine (T) N9 N1
Each bases has its preferred s tautomeric form /Related to Ch 9) amino imino H N N N H—Nf N keto enol H N N H H-bond donor H-bond acceptor Copyright o 2004 Pearson Education, Inc. publishing as Benjamin Cummings
DNA STRUCTURE ( ) 2 Each bases has its preferred tautomeric form (Related to Ch 9)
The two strands of the double helix are held together by base pairing in an antiparallel orientation, Which is a stereochemical(立体化学 E)consequence of the way that adenine and u thymine, and guanine and cytosine, pair with s each other. (Related to replication and transcription CHa sugarphosphate CHa Copyright o 2004 Pearson Education, Inc, publishing as Benjamin Cummings A
The two strands of the double helix are held together by base pairing in an antiparallel orientation, Which is a stereochemical (立体化学 的) consequence of the way that adenine and thymine, and guanine and cytosine, pair with each other. (Related to replication and transcription) DNA STRUCTURE ( ) 3
The two chains of the double helix have Complementary Sequences Watson-Crick Base Pairing Example: If sequence 5-ATGTC-3 on one chain, the opposite chain MUst have the complementary sequence 3 TACAG-5 (Related to replication and transcription)
The Two Chains of the Double Helix Have Complementary Sequences Example: If sequence 5’-ATGTC-3’ on one chain, the opposite chain MUST have the complementary sequence 3’- TACAG-5’ DNA STRUCTURE ( ) 4 Watson-Crick Base Pairing (Related to replication and transcription)