《分子生物学》课程PPT教学课件（讲义）lect1 Molecular Biology

Molecular Biology Molecular biology is usually described as that domain of biology that seeks explanations in terms of the structure and function of molecules of the cell and sometimes of the whole organism. These molecules are most frequently macromolecules such as proteins, nucleic acids and carbohydrates or molecular assemblies such as lipidcontaining membranes and viruses

Molecular Biology Molecular biology is usually described as that domain of biology that seeks explanations in terms of the structure and function of molecules of the cell and sometimes of the whole organism. These molecules are most frequently macromolecules such as proteins, nucleic acids and carbohydrates, or molecular assemblies such as lipidcontaining membranes, and viruses

DNA Replication Infor matio DNA duplicates MOOd 入入00A风A0 DNA ranscnpton RNA synthe RNA mRNA nucleus nformation cytoplasm nuclear envelope Translatio Protein synthesis Protein Ribosome Protein The Central Dogma of Molecular Biology

Gene Expression DNA Transcription ranscription Translation mrNA Translation Protein

Gene Expression DNA mRNA Protein Transcription Translation Transcription Translation

20? GC Deoxyribonucleic acid (DNA) is the genetic material Stores genetic information in at Groove the form of a code: a linear TA sequence of nucleotides Major Groove TA 34? Replicated by copying the strands using each as a Strands are antiparallel GC template for the production of the complementary strand

34 ? 3.4 ? 20 ? Minor Groove Major Groove G C CG AT TA CG G C AT TA TA AT G C CG G C Strands are antiparallel Deoxyribonucleic acid (DNA) is the genetic material -Stores genetic information in the form of a code: a linear sequence of nucleotides -- Replicated by copying the strands using each as a template for the production of the complementary strand

A. Onganicchemistry mode B Ribbon model C Space filling model (singlestrandedDNA) doublestranded dna(double stranded DNA) 5 phasphate βDNA CH. o T 3C nucleotide 0 H N-H 0=P—0 0 This ring is deoxyribose Minor groove 5C/ Phosphodiester Bond H A 3 hydroxyl dNA has a phosphodiester sugar backbone

DNA has a phosphodiester sugar backbone

Nucleosides(of DNa)-Precursors to Nucleotides Nucleoside base sugar c HN HOCH2 O HOCH 2 HOC H2 HOCH2 O H H OH 2-deoxy -ADENOSINE 2-deoxy- GUANOSINE 2-deoxy- THYMIDINE 2-deoxy - CYTIDINE Sugar= deoxyribose; 6 carbons, no OH on the 2nd(or 2) carbon base is attached to carbon 1

Nucleosides (of DNA) – Precursors to Nucleotides Nucleoside = base + sugar Sugar = deoxyribose; 6 carbons, no OH on the 2nd (or 2’) carbon; base is attached to carbon 1

The 4 nucleotides of dna 2-deoxyadenos ne 5 triphosphate 2-deoxyguanos ne 5 triphosphate HN 0 0-H2 3 2-deaxycytid ne 5 triphosphate timid ne 5 triphosphate CH 0—P-0—20

The 4 Nucleotides of DNA

RNA Mole cular Diffe rences between Ribonucleic Acid (RNA) 2-deoxy-nbonucleic acid DNA) RNA DNA 5 HOCH2 HOCH2 H RIBOSE 2-DEOXY-RIBOSE CH URACIL YMINE Ribose replaces deoxyribose; uracil replaces thymine

Ribose replaces deoxyribose; uracil replaces thymine RNA

Before we continue some terminology Nucleotide name table P lines rimidin es Aden ine(a) Guanine(G) Cytosine(C) Thy mine(t) Uracil (U) Nucleotides in dna deoxyadenylate deoxyguany late deoxycytidy late deoxythy midylate thymid late Nucleotides in rna aden ylate guany late cytidy late uridylate Abbreviations Nucleo sid AMP GMP CMP TMP UMP monophos phates Nucleoside A DP GDP CDP TDP UDP diphos ph Nucleo side GTP CTP UTP trip hos phates For deoxynucleotides add 'd in front of the above three e.g., AMP is a ribonucleotide, dAMP is a deoxyribonucleotide

Before we continue some terminology Nucleotide Name Table Purines Pyrimidines Adenine (A) Guanine (G) Cytosine (C) Thymine (T) Uracil (U) Nucleotides in DNA deoxyadenylate deoxyguanylate deoxycytidylate deoxythymidylate or thymidylate Nucleotides in RNA adenylate guanylate cytidylate uridylate Abbreviations Nucleoside monophosphates AMP GMP CMP TMP UMP Nucleoside diphosphates ADP GDP CDP TDP UDP Nucleoside triphosphates ATP GTP CTP TTP UTP For deoxynucleotides add 'd' in front of the above three. e.g., AMP is a ribonucleotide, dAMP is a deoxyribonucleotide

Copyright@ The McGraw-Hill Companies, Permission required for reproduction or display. H3C In dna and rna 5-phosphate nucleotides are held together by -O-P-O-CH phosphodiester bonas NI N Phosphodiester bonds O=P-0-CH Figure 2.10 OH 3-hydroxyl

In DNA and RNA, nucleotides are held together by phosphodiester bonds