Detailed Contents Integral Membrane Proteins Are Firmly Anchored The properties of pyrimidines and purines can be traced in the Membrane 280 to Their Electron-Rich Nature 327 Lipid-Anchored Membrane Poten Are Switching 10.2 What Are Nucleosides?328 HUMAN BIOCHEMISTRY:Adenosine:A Nucleoside with Physiological Activity 328 10.3 93 What Are the Structure and Chemistry of Nucleotides?329 Structures 290 Cyclic Nucleotides Are Cyclic Phosphodiesters 330 94 What are the dynamic Processes that modulate phosphates Are 330 Membrane Function?291 HUMAN BIOCHEMISTRY Lipids and Proteins Undergo a Variety of Movements mbranes NDPs and NTPs Are Polyprotic Acids 332 embrane Lipids Can BeOrdered to Different Extents 292 Nucleosie 5'Triphosphates Are Carriers of Chemical 9.5 nergy 33. 10.4 What Are Nucleic Acids?333 9.6 What Is Passive Diffusion?301 10.5 What Are the Different Classes of Nucleic Acids?334 How Does Facilitated Diffusion Occur?301 ne Fundamenta s a D Membrane Channel Proteins Facilitate Diffusion 30. arious Forms RNA Serve Differen es in Cells 337 The esa Variation Practical Applications?339 Coa Pentameric 305 A DEEPER LOOK-The rNA world and farly fvolution 342 Chloride Water.Glyce erol.and Ammonia Flow Through The Chemical Differences Between DNA and RNA Have Single-Subunit Pores 306 Biological Significance 342 98 How Does Energy Input Drive Active Transport 10.6 Are Nucleic Acids Susceptible to Hydrolysis?343 Processes?307 RNA Is Susceptible to Hydrolysis by Base.but DNA nspor sem Are Eergy-oupin s Not 343 y Nucleases Differ in Their Specificity for Different Forms of Nucleic Acid 345 ABC Transporters Use ATP to Drive Import and Export Functions and Provide Multidrug Resistance 313 9.9 How Are Certain Transport Processes Driven e Useful by Light Energy?315 the Structureo 9.10 lary Active Transport Driven by lon SUMMARY 349 321 FOUNDATIONAL BIOCHEMISTRY 350 Naand HDrive Secondary Active Tra ort 316 PROBLEMS 351 AcrB Is a Secondary Active Tr. FURTHER READING 352 SUMMARY 318 11 Structure of Nucleic Acids 353 BIOCHEMISTRY 319 1 PROBLEMS 319 FURTHER READING 321 ence of DNa Can be d nad 10 Nucleotides and nucleic Acids 325 from the Electrophoretic Mig of Polynu 10.1 What Are the stru re and Chemistry of Nitroge nous Bases?326 ocanomeDte2ahodUse Three P rimidines and Two Purines Are Commonly Found of Polynucleotide Fragments 354 in Cells 326 Next-Generation Sequencing 356 ee ce Detailed Contents xi The Properties of Pyrimidines and Purines Can Be Traced to Their Electron-Rich Nature 327 10.2 What Are Nucleosides? 328 Human Biochemistry: Adenosine: A Nucleoside with Physiological Activity 328 10.3 What Are the Structure and Chemistry of Nucleotides? 329 Cyclic Nucleotides Are Cyclic Phosphodiesters 330 Nucleoside Diphosphates and Triphosphates Are Nucleotides with Two or Three Phosphate Groups 330 Human Biochemistry: cGAMP, A Cyclic Dinucleotide That Triggers a Response to Infection 331 NDPs and NTPs Are Polyprotic Acids 332 Nucleoside 59-Triphosphates Are Carriers of Chemical Energy 332 10.4 What Are Nucleic Acids? 333 The Base Sequence of a Nucleic Acid Is Its Defining Characteristic 333 10.5 What Are the Different Classes of Nucleic Acids? 334 The Fundamental Structure of DNA Is a Double Helix 334 Various Forms of RNA Serve Different Roles in Cells 337 A Deeper Look: Do the Properties of DNA Invite Practical Applications? 339 A Deeper Look: The RNA World and Early Evolution 342 The Chemical Differences Between DNA and RNA Have Biological Significance 342 10.6 Are Nucleic Acids Susceptible to Hydrolysis? 343 RNA Is Susceptible to Hydrolysis by Base, but DNA Is Not 343 The Enzymes That Hydrolyze Nucleic Acids Are Phosphodiesterases 343 Nucleases Differ in Their Specificity for Different Forms of Nucleic Acid 345 Restriction Enzymes Are Nucleases That Cleave Double-Stranded DNA Molecules 345 Type II Restriction Endonucleases Are Useful for Manipulating DNA in the Lab 346 Restriction Endonucleases Can Be Used to Map the Structure of a DNA Fragment 349 SUMMARY 349 Foundational Biochemistry 350 PROBLEMS 351 Further Reading 352 11 Structure of Nucleic Acids 353 11.1 How Do Scientists Determine the Primary Structure of Nucleic Acids? 353 The Nucleotide Sequence of DNA Can Be Determined from the Electrophoretic Migration of a Defined Set of Polynucleotide Fragments 354 Sanger’s Chain Termination or Dideoxy Method Uses DNA Replication to Generate a Defined Set of Polynucleotide Fragments 354 Next-Generation Sequencing 356 Integral Membrane Proteins Are Firmly Anchored in the Membrane 280 Lipid-Anchored Membrane Proteins Are Switching Devices 287 Human Biochemistry: “Fat-Free Proteins” May Point the Way to Drugs for Sleeping Sickness 289 9.3 How Are Biological Membranes Organized? 290 Membranes Are Asymmetric and Heterogeneous Structures 290 9.4 What Are the Dynamic Processes That Modulate Membrane Function? 291 Lipids and Proteins Undergo a Variety of Movements in Membranes 291 Membrane Lipids Can Be Ordered to Different Extents 292 9.5 How Does Transport Occur Across Biological Membranes? 300 9.6 What Is Passive Diffusion? 301 Charged Species May Cross Membranes by Passive Diffusion 301 9.7 How Does Facilitated Diffusion Occur? 301 Membrane Channel Proteins Facilitate Diffusion 302 The B. cereus NaK Channel Uses a Variation on the K1 Selectivity Filter 304 CorA Is a Pentameric Mg21 Channel 305 Chloride, Water, Glycerol, and Ammonia Flow Through Single-Subunit Pores 306 9.8 How Does Energy Input Drive Active Transport Processes? 307 All Active Transport Systems Are Energy-Coupling Devices 307 Many Active Transport Processes Are Driven by ATP 308 A Deeper Look: Cardiac Glycosides: Potent Drugs from Ancient Times 312 ABC Transporters Use ATP to Drive Import and Export Functions and Provide Multidrug Resistance 313 9.9 How Are Certain Transport Processes Driven by Light Energy? 315 Bacteriorhodopsin Uses Light Energy to Drive Proton Transport 315 9.10 How Is Secondary Active Transport Driven by Ion Gradients? 316 Na1 and H1 Drive Secondary Active Transport 316 AcrB Is a Secondary Active Transport System 316 SUMMARY 318 Foundational Biochemistry 319 PROBLEMS 319 Further Reading 321 10 Nucleotides and Nucleic Acids 325 10.1 What Are the Structure and Chemistry of Nitrogenous Bases? 326 Three Pyrimidines and Two Purines Are Commonly Found in Cells 326 Copyright 2017 Cengage Learning. 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