Microbial physiology

1 INTRODUCTION TO MICROBIAL PHYSIOLOGY 1 The Escherichia coli Paradigm / 1 Cell Structure / 1 The Cell Surface / 1 Synthesis of DNA, RNA, and Protein / 7 Metabolic and Genetic Regulation / 10 Microbial Genetics / 11 Chemical Synthesis / 12 Chemical Composition / 12 Energy / 13 Oxidation–Reduction Versus Fermentation / 15 Nitrogen Assimilation / 18 Special Topics / 19 Endospores / 19 Growth / 19 Continuous Culture / 22 Factors Affecting Growth / 22 Nutrition / 22 Oxygen / 24 Carbon Dioxide / 24 v vi CONTENTS Extremophiles / 25 Microbial Stress Responses / 26 Summary / 26 2 MACROMOLECULAR SYNTHESIS AND PROCESSING: DNA, RNA, AND PROTEIN SYNTHESIS 27 Structure of DNA / 28 Bacterial Nucleoids / 31 REP Elements / 35 DNA Replication / 36 DNA Replication is Bidirectional and Semiconservative / 36 DNA Polymerase Functions as a Dimer / 36 Model of DNA Replication / 39 Initiation of DNA Replication / 42 Termination of DNA Replication and Chromosome Partitioning / 46 RNA Synthesis: Transcription / 47 RNA Synthesis / 47 RNA Turnover / 53 RNA Processing / 54 Protein Synthesis: Translation / 57 Transfer RNA / 59 Charging of tRNA / 62 Ribosome Structure and Synthesis / 62 Initiation of Polypeptide Synthesis / 68 Elongation / 69 Peptide Bond Formation / 71 Translocation / 71 Termination / 72 Posttranslational Processing / 73 When Nonsense Makes Sense / 74 Coupled Transcription and Translation / 74 Protein Folding and Chaperones / 74 Folding Stages / 75 Protein Folding and Chaperone Mechanisms Outside the Cytoplasm / 76 Quality Control / 77 Protein Trafficking / 77 Insertion of Integral Membrane Proteins and Export of Periplasmic Proteins / 77 Secretion of Proteins Across the Outer Membrane / 81 vii Protein Degradation / 83 Degradation of Abnormal Proteins / 83 Energy-Dependent Proteases / 86 Antibiotics that affect Nucleic Acid and Protein Synthesis / 88 Agents Affecting DNA Metabolism / 88 Agents Affecting Transcription / 91 Agents Affecting Translation / 92 Nucleoids / 98 DNA Replication / 98 Transcription and Translation / 98 Protein Folding, Trafficking, and Degradation / 99 Antibiotics / 100 3 BACTERIAL GENETICS: DNA EXCHANGE, RECOMBINATION, MUTAGENESIS, AND REPAIR 101 Transfer of Genetic Information in Prokaryotes / 101 Plasmids / 102 Partitioning / 102 Incompatibility / 103 Nonconjugative, Mobilizable Plasmids / 103 Resistance Plasmids / 104 Plasmids in Other Bacterial Genera / 104 Plasmid Replication / 104 Addiction Modules: Plasmid Maintenance by Host Killing: The ccd Genes / 108 Conjugation / 108 F Factor / 108 cis/trans complementation Test / 115 Conjugation and Pheromones in Enterococci / 116 Conjugation, Cell–Cell Signaling, and Bacterial-Induced Tumors / 117 Transformation / 118 Gram-Positive Transformation / 119 Gram-Negative Transformation / 123 Transfection and Forced Competence / 124 Transduction / 124 Recombination / 127 General Recombination / 128 Genetics of Recombination / 131 Restriction and Modification / 133 viii CONTENTS Insertion Sequences and Transposable Elements / 138 Transposon Tn10 / 140 Transposon Tn3 / 143 Conjugative Transposition / 144 Evolutionary Consideration / 144 Integrons / 145 Mutagenesis / 145 Spontaneous Mutations / 147 The Nature of Mutational Events / 147 Suppressor Mutations / 149 DNA Repair Systems / 152 Photoreactivation / 152 Nucleotide Excision Repair / 152 Transcription-Coupled Repair / 155 Methyl-Directed Mismatch Repair / 156 Very Short-Patch Mismatch Repair / 158 DNA Glycosylases and Base Excision Repair / 158 Adaptive Response to Methylating and Ethylating Agents / 160 Postreplication Daughter Strand Gap Repair / 160 SOS-Inducible Repair / 162 Replication Restart / 165 Adaptive Mutations / 166 Plasmids / 167 Transformation / 167 Conjugation / 168 Recombination / 168 Restriction Modification / 169 Transposition / 169 Mutagenesis / 169 Repair Mechanisms / 170 4 MICROBIAL PHYSIOLOGY IN THE GENOMIC ERA: A REVOLUTIONARY TALE 171 Genomic and Proteomic Tools / 172 Cloning a Genome / 172 DNA Sequencing / 172 Web Science: Internet Tools for DNA Sequence Analysis / 173 Gene Replacement / 176 Gene Arrays / 177 Proteomics / 177 ix Traditional Tools / 181 Mutant Hunts / 181 Transcriptional and Translational Gene Fusions (Reporter Genes) / 182 Polymerase Chain Reaction / 183 DNA Mobility Shifts (Gel Shifts and Supershifts) / 185 Finding Transcriptional Starts by Primer Extension / 186 Detecting DNA, RNA, Protein, and DNA-Binding Proteins by Southern, Northern, Western, and Southwestern Blots / 187 Two-Hybrid Analysis / 190 Summary / 192 5 REGULATION OF PROKARYOTIC GENE EXPRESSION 194 Transcriptional Control / 194 DNA-Binding Proteins / 195 The lac Operon: A Paradigm of Gene Expression / 197 Catabolite Control: Sensing Energy Status / 201 Class I and Class II CRP-Dependent Genes / 204 The Catabolite Repressor/Activator Protein Cra / 204 Catabolite Control: The Gram-Positive Paradigm / 206 The gal Operon: DNA Looping with a Little Help from Hu / 206 The Arabinose Operon: One Regulator, Two Functions / 208 Attenuation Controls / 211 Transcriptional Attenuation Mechanisms / 211 Translational Attenuation Control: The pyrC Strategy / 215 Membrane-Mediated Regulation: The put System / 216 Recombinational Regulation of Gene Expression (Flagellar Phase Variation) / 217 Translational Repression / 219 Anti-σ Regulation by Molecular Hijacking / 220 Titrating a Posttranscriptional Regulator: The CsrA/CsrB Carbon Storage Regulatory Team / 222 Global Control Networks / 223 Communication with the Environment: Two-Component Regulatory Systems / 224 Regulation of Nitrogen Assimilation and Nitrogen Fixation: Examples of Integrated Biochemical and Genetic Controls / 227 Phosphate Uptake: Communication Between Transport and Two-Component Regulatory Systems / 232 x CONTENTS Quorum Sensing: How Bacteria Talk to Each Other / 234 Proteolytic Control / 235 Summary / 236 6 BACTERIOPHAGE GENETICS 239 General Characteristics of Bacteriophages / 239 T4 Phage / 245 Structure / 245 General Pattern of T4 Gene Expression / 247 T4 Genome / 250 λ Phage / 256 The Lysis-Lysogeny Decision / 259 Transcription / 259 Function of Cro Versus CI Repressor and the Structure of OL and OR / 260 Establishment of Repressor Synthesis / 260 Control of Integration and Excision / 262 Negative Retroregulation of int by sib / 263 λ-Phage Replication / 264 μ Phage: Transposition as a Lifestyle / 266 X174 / 271 Summary / 274 General / 274 T4 Bacteriophage / 274 λ Phage / 275 φX174 / 275 μ Phage / 275 7 CELL STRUCTURE AND FUNCTION 277 The Eukaryotic Nucleus / 277 Bacterial Nucleoids / 279 Nucleosomes / 283 Mitochondria / 287 Microbial Cell Surfaces / 288 Eukaryotic Cell Surfaces / 288 Prokaryotic Cell Surfaces / 289 Surface Layers of Bacteria / 290 Peptidoglycans of Bacterial Cell Walls / 290 Peptidoglycan (Murein) Hydrolases / 295 Peptidoglycan (Murein) Synthesis / 295 Teichoic Acids and Lipoteichoic Acids / 300 Outer Membranes of Gram-Negative Bacteria / 303 xi Lipopolysaccharide Biosynthesis / 308 Enterobacterial Common Antigen / 309 Cytoplasmic Membranes / 310 Permeability and Transport / 313 Periplasm / 313 Other Membranous Organelles / 314 Capsules / 315 Microbial Biofilms / 322 Organs of Locomotion / 323 Cilia and Flagella of Eukaryotes / 323 Bacterial (Prokaryotic) Flagella / 325 Chemotaxis / 328 Swarming Motility / 334 Motility in Spirochetes / 337 Gliding Motility / 339 Pili or Fimbriae / 340 Nucleus, Nucleosomes, and Nucleoids / 343 Mitochondria / 344 Eukaryotic Cell Surface / 344 Surface (S) layers / 344 Bacterial Cell Wall Peptidoglycan (Murein) / 345 Teichoic and Lipoteichoic Acids / 346 Outer Membrane / 346 Cytoplasmic Membrane / 346 Periplasm / 346 Capsules / 346 Biofilms / 347 Cilia and Flagella of Eukaryotes / 347 Bacterial Flagella / 347 Chemotaxis / 348 Swarming Motility / 348 Gliding Motility / 348 Motility in Spirochetes / 348 Pili or Fimbriae / 349 8 CENTRAL PATHWAYS OF CARBOHYDRATE METABOLISM 350 Alternate Pathways of Carbohydrate Metabolism / 351 Fructose Bisphosphate Aldolase Pathway / 351 Alternate Pathways of Glucose Utilization / 354 Entner-Doudoroff or Ketogluconate Pathway / 354 Phosphoketolase Pathway / 356 Oxidative Pentose Phosphate Cycle / 358 xii CONTENTS Gluconeogenesis / 360 Regulation / 360 Glycogen Synthesis / 361 Tricarboxylic Acid Cycle / 361 Glyoxylate Cycle / 365 9 ENERGY PRODUCTION AND METABOLITE TRANSPORT 368 Energy Production / 368 Substrate-Level Phosphorylation / 369 Oxidative Phosphorylation / 371 Measurement of PMF / 372 Electron Transport Systems / 373 Anaerobic Respiration / 376 Conversion of PMF to Energy / 377 Structure of F1F0 and the atp Operon / 379 Energy Yield / 380 Generating ATP in Alkalophiles / 380 Energetics of Chemolithotrophs / 380 pH Homeostasis / 382 Metabolite Transport / 383 Facilitated Diffusion / 383 Mechanosensitive Channels / 385 ATP-Binding Cassette Transporter Family / 385 Chemiosmotic-Driven Transport / 385 Establishing Ion Gradients / 387 Specific Transport Systems / 387 ATP-Linked Ion Motive Pumps / 387 The Histidine Permease / 389 Iron / 389 Phosphotransferase System / 390 Summary / 392 Energy Production / 392 Metabolite Transport / 392 10 METABOLISM OF SUBSTRATES OTHER THAN GLUCOSE 394 Utilization of Sugars other than Glucose / 394 Lactose / 394 Galactose / 396 Maltose / 396 xiii Mannitol / 396 Fucose and Rhamnose / 397 Mellibiose, Raffinose, Stachyose, and Guar Gum / 399 Pectin and Aldohexuronate Pathways / 400 Cellulose Degradation / 402 Starch, Glycogen, and Related Compounds / 403 Metabolism of Aromatic Compounds / 407 Pectin Utilization / 410 Cellulose Utilization / 410 Utilization of Starch, Glycogen, and Related Compounds / 411 Utilization of Aromatic Hydrocarbons / 411 11 FERMENTATION PATHWAYS 412 Fermentation Balances / 412 Yeast Fermentation / 415 Lactic Acid–Producing Fermentations / 417 Butyric Acid—and Solvent-Producing Fermentations / 423 Fermentations of the Mixed-Acid Type / 425 Propionic Acid Fermentation / 428 Acetic Acid Fermentation / 430 Fermentation Pathways / 431 Yeast Fermentation / 431 Lactic Acid Fermentation / 432 Butyric Acid and Solvent-Producing Fermentations / 432 Mixed-Acid Fermentations / 433 Propionic Acid Fermentation / 433 Acetic Acid Fermentation / 433 12 PHOTOSYNTHESIS AND INORGANIC METABOLISM 434 Characteristics and Metabolism of Autotrophs / 434 Photosynthetic Bacteria and Cyanobacteria / 434 Autotrophic CO2 Fixation and Mechanisms of Photosynthesis / 437 Hydrogen Bacteria / 440 Nitrifying Bacteria / 442 Sulfur Bacteria / 442 Iron Bacteria / 443 Methylotrophs / 444 Methanogens / 446 xiv CONTENTS 13 LIPIDS AND STEROLS 450 Lipid Composition of Microorganisms / 451 Straight-Chain Fatty Acids / 451 Branched-Chain Fatty Acids / 453 Ring-Containing Fatty Acids / 454 Alk-1-enyl Ethers (Plasmalogens) / 455 Alkyl Ethers / 456 Phospholipids (Phosphoglycerides) / 457 Glycolipids / 458 Biosynthesis of Fatty Acids / 459 Biosynthesis of Phospholipids / 464 Degradation of Fatty Acids / 466 Biosynthesis of Isoprenoids / 468 14 NITROGEN METABOLISM 475 Biological Nitrogen Fixation / 475 The Nitrogen Fixation Process / 479 Components of the Nitrogenase System / 480 Symbiotic Nitrogen Fixation / 483 Inorganic Nitrogen Metabolism / 487 Assimilation of Inorganic Nitrogen / 492 General Reactions of Amino Acids / 494 Amino Acid Decarboxylases / 494 Amino Acid Deaminases / 495 Amino Acid Transaminases (Aminotransferases) / 497 Amino Acid Racemases / 498 Role of Pyridoxal-5
-Phosphate in Enzymatic Reactions with Amino Acids / 499 The Stickland Reaction / 500 Nitrogen Fixation / 501 Inorganic Nitrogen / 502 Urease / 502 Assimilation of Inorganic Nitrogen / 502 15 BIOSYNTHESIS AND METABOLISM OF AMINO ACIDS 503 The Glutamate or α-Ketoglutarate Family / 503 Glutamine and Glutathione Synthesis / 503 The Proline Pathway / 504 Aminolevulinate Synthesis / 504 The Arginine Pathway / 504 xv Polyamine Biosynthesis / 509 The α-Ketoadipate Pathway to Lysine / 510 The Aspartate and Pyruvate Families / 513 Asparagine Synthesis / 513 The Aspartate Pathway / 514 The Bacterial Pathway to Lysine / 515 Threonine, Isoleucine, and Methionine Formation / 516 Isoleucine, Valine, and Leucine Biosynthesis / 518 Regulation of the Aspartate Family / 518 The Serine-Glycine Family / 520 Aminolevulinate and the Pathway to Tetrapyrroles / 523 The Aromatic Amino Acid Pathway / 523 Phenylalanine, Tyrosine, and Tryptophan / 523 The Common Aromatic Amino Acid Pathway / 525 Pathways to Tyrosine and Phenylalanine / 526 p-Aminobenzoate and Folate Biosynthesis / 531 Enterobactin Biosynthesis / 533 The Pathway to Ubiquinone / 534 Menaquinone (Vitamin K) Biosynthesis / 534 Biosynthesis of Nicotinamide Adenine Dinucleotide (NAD) / 534 Histidine Biosynthesis / 539 Amino Acids / 541 Glutamate (α-Ketoglutarate) Family / 541 Aspartate and Pyruvate Families / 542 Serine-Glycine Family / 543 Aromatic Amino Acid Family / 543 Histidine / 544 16 PURINES AND PYRIMIDINES 545 Biosynthesis of Purines / 545 Biosynthesis of Pyrimidines / 550 Interconversion of Nucleotides, Nucleosides, and Free Bases: Salvage Pathways / 554 Regulation of Purine and Pyrimidine Biosynthesis / 555 Purines and Pyrimidines / 559 Riboflavin Biosynthesis / 560 Thiamine Biosynthesis / 560 17 BACTERIAL CELL DIVISION 561 Cell Division in Gram-Negative Rods / 561 Cell Division in Gram-Positive Cocci / 570 xvi CONTENTS Cell Division in Gram-Positive Bacilli / 575 General Reviews / 578 Cell Division in Gram-Negative Rods / 579 Cell Division in Gram-Positive Cocci / 580 Cell Division in Gram-Positive Bacilli / 581 18 MICROBIAL STRESS RESPONSES 582 Osmotic Stress and Osmoregulation / 582 High Osmolality / 583 Low Osmolality / 584 Osmotic Control of Gene Expression / 585 Aerobic to Anaerobic Transitions / 587 Formate Nitrate Regulation / 589 Nitrate Response / 589 ArcAB System / 591 Oxidative Stress / 592 Regulation of the Oxidative Stress Response / 594 pH Stress and Acid Tolerance / 596 Thermal Stress and the Heat Shock Response / 597 Nutrient Stress and the Starvation—Stress Response / 601 Starvation—Stress Response / 601 Stringent Control / 602 Extremophiles / 605 Summary / 608 Osmotic Stress and Osmoregulation / 608 Aerobic to Anaerobic Transitions / 609 Oxidative Stress / 609 pH Stress and Acid Tolerance / 610 Thermal Stress and the Heat Shock Response / 610 Nutrient Stress and the Starvation Stress Response / 611 Stringent Control / 611 Extremophiles / 611 19 BACTERIAL DIFFERENTIATION 612 Bacillus Endospore Formation / 612 Life Cycle of Bacillus / 613 Stages of Sporulation / 614 Physiological and Genetic Aspects of Sporulation / 616 Sporulation Genes / 616 Initiation / 617 xvii Transition from Stage II to Stage III / 619 Forespore Development / 620 Final Stages of Sporulation / 621 Spore Cortex Synthesis / 622 Spore Coat Protein Synthesis / 622 Activation, Germination, and Outgrowth of Bacterial Endospores / 623 Activation / 624 Germination / 624 Outgrowth / 627 Myxobacterial Developmental Cycle / 628 Life Cycle of Myxobacteria / 628 Aggregation and Fruiting Body Formation / 629 Genetics of Myxococcus xanthus Development / 632 Caulobacter Differentiation / 637 Life Cycle of Caulobacter crescentus / 637 The Stalk, the Holdfast, and the Flagellum: Structure, Genetics, and Regulation / 638 Regulation and Checkpoints of the Cell Cycle of C. crescentus / 642 Endospore Formation / 644 Germination and Outgrowth of Endospores / 645 Myxobacterial Developmental Cycle / 646 Caulobacter Differentiation / 647 20 HOST–PARASITE INTERACTIONS 648 Overview of Host–Parasite Relationships / 648 Structures and Functions Involved in Host–Parasite Interactions / 650 Adherence/Colonization / 650 Virulence Factor Secretion Systems / 653 Exotoxins / 658 Quorum Sensing / 664 Paradigms of Bacterial Pathogenesis / 669 Enteropathogenic Escherichia coli / 669 Salmonella Enterica Serovars / 669 Listeria Monocytogenes / 670 Chlamydia spp / 672 Overview / 672 Adherence/Colonization / 672 Virulence Factor Secretion Systems / 673 xviii CONTENTS Exotoxins / 673 Quorum Sensing / 674 Paradigms of Bacterial Pathogenesis / 675 INDEX 676