Microbiology chapter 11 notes

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Microbiology chapter 11 notes
2012-10-25 19:06:45
prescott microbiology harley chapter 11

Chapter 11 questions from notes
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  1. Define anabolism
    microbes synthesize new organelles and cells from sources of C and inorganic molecules
  2. continual degradation and resynthsis of cellular constituents
  3. T/F
    The rate of turnover is balanced by the rate of biosynthesis
  4. Macromolecules are synthesized from what
    a limited number of simple structural units (monomers)
  5. T/F
    Enzymes are only used for catabolic processes
    • False
    • Enzymes are used for both catabolic and anabolic processes
  6. How to anabolic pathways work in relation to biosynthsis
    They work irreversibly to synthesis molecules by breaking down ATP
  7. Where are anabolic and catabolic reactions in relation to each other in eucaryotes?
    they are separate from each other to operate simultaneously but independently
  8. What cofactor does catabolism use
  9. What is the electron donor for anabolism
  10. how are large assemblies like ribosome made 
    for spontaneously from macromolecules by self-assembly
  11. intermediates of pathways that serve as starting molecules for biosynthetic pathwyas
    precursor metabolites
  12. T/F
    Anabolism does not require precuror metabolites
    • False
    • They're actually pretty important
  13. used as starting substrates for biosynthetic pathways
    C skeletons
  14. what are most c skeletons used for 
    biosynthsis of amino acids
  15. List th four ways autotrophs can fix CO2
    • calvin cycle
    • reductive TCA cycle
    • acetyl-coA pathway
    • hydroxypropionate cycle
  16. also called reductive pentose phospate cycle, this is the pathway used most by autotrophs to fix CO2
    calvin cycle
  17. where does the calvin cycle occur
    • in the stroma of chloroplasts (eucaryotes)
    • in carboxysomes (cyanobacteria, nitrifying, and thiobacilli)
  18. What overall is needed to incorporate 1 CO2 in the calvin cycle
    • 3 ATP's 
    • 2 NADPH's
  19. 3 phases of the calvin cycle
    • carboxylation
    • reductions
    • regeneration
  20. what enzyme in carboxylation is used
    ribulose 1,5-biphosphate carboxylase (rubisco)
  21. What is the most abundant enzyme on earth
  22. what does rubisco do
    catalyzes co2 to 2 molecules of 3-PGA
  23. What happens in th reduction phase of the calvin cycle
    • 3 phosho glycerate reduced to glyceraldehyde 3 phosphate
    • uses ATP and NADPH
  24. What happens in the regeneration phase of the calvin cycle
    • RuBP regenerated
    • more ATP used
    • carbohydrates produced (glucose)
  25. what organism uses the acetyl-CoA pathway
  26. what uses the reductive TCA cycle
    some chemolithoautotrophs (green sulfur bacteria)
  27. what uses the hydroxypropionate cycle
    some archaea (anoxygenic photorophs)
  28. synthsis of glucose, fructose, and related sugars from noncarbohydrate precursors
  29. what's the reversal of glycolysis
  30. how many enzymes are unique to gluconeogenesis
  31. what intermediates are used to gluconeogenesis
    glucose, fructose, and mannose
  32. how is galactose synthesized in gluconeogenesis
    nucleoside diphosphate derivatives
  33. nucleoside diphosphate sugars
    used in synthesis of monosacaride and polysaccharides
  34. Summary of peptidoglycan synthesis
    bactroprenol, a lipid carrier, transports NAG-NAM unites across the cell membrane

    then cross links between peptidoglycan strands are formed by transpeptidation

    bactoprenol moves back and loses a phosphate so it can redo the process
  35. The last step in peptidoglycan formation
  36. carry out limited digestion of peptidoglycan 
    allow new material to be added to wall
  37. What are the 2 general patterns that cell walls form
    • growth at one or two sites (gram posititve)
    • growth sites scattered (rod shaped)
  38. used as starting substrates for synthsis of amino acids
    precursor metabolites
  39. T/F
    N addition to C skeleton is an important step in synthesis of amino acids
  40. Two mechanisms for ammonia incorporation into carbon skeleton
    • 1. reductive animation using glutamate dehydrogenase (GDH)
    • 2. glutamine synthetase-glutamate synthase systems
  41. Transfer Nitrogen to other C skeletons after incorporation
  42. What acts as the amino donor in ammonia incorporation using glutamine sythetase-glutamate sythase? where do the electrons come from?
    • glutamate
    • NADPH
  43. Bacteria reduce nitrate to ammonia and then incorporate it into an organic form
    assimilatory nitrate reduction
  44. nitrate reduction to nitrite or ammonia is catalyzed by what
    nitrate reductase
  45. reduction of atmospheric nitrogen to ammonia
    nitrogen fixation
  46. what is the catalist in nitrogen fixation
  47. who does nitrogen fixation
    a few species of procaryotes
  48. how much energy does nitrogen fixation require
     a lot of ATP
  49. What is sulfur needed for in cells
    sythesis of amino acids cysteine and methionine plus several coenzymes
  50. where is sulfure obtained from
    • external sources
    • intracellular amino acid reserves
  51. sulfate is reduced to H2S and then used to synthesize cysteine
    assimilatory sulfate reduction
  52. how is assimilatory sulfate reduction different from dissimilatory?
    • diss-sulfate acts as electron acceptor for anaerobic respiration
    • ass- for biosynthsis and gets its reducing power from NADPH and ATP
  53. where is phosphorus found in a cell
    proteins, phospholipids, ATP, and coenzymes
  54. Common sources of phosphorus
    inorganic phosphate and organic phospate esters
  55. how is inorganic phosphate assimilated
    its incorporation in ATP formation by photophosphorylation, oxidative phosphorylation, substrate-level phosphorylation
  56. how are organic phosphate esters assimlated
    hydroylzed by phosphatases, releasing Pi
  57. T/F
    one precursor metabolite can give rise to only one amino acid
    • Falso
    • one metabolite can do several amino acids
    • plus they share intermediates
  58. replenishment of TCA cycle intermediates provided by
    Anaplerotic Reactions
  59. allows tca cycle to function during periods of active biosynthesis
    Anaplerotic Reactions
  60. a modified TCA cycle where the acetyl group is assimilated into oxaloacetate without loss of CO2
    glyoxalate cycle
  61. T/F
    most microbes can sythesize their own purines and pyrimidines
  62. cyclic nitrogenous bases consiting of 2 joined rings
    (adenine and guanine)
  63. cyclic nitrogenous bases consisting of single ring
    (uracil, cytosine, thymine)
  64. nitrogenase base-pentose sugar
  65. nucleoside-phosphate
  66. complex pathway in which several molecules contribute parts to the final purine skeleton
    purine biosynthsis
  67. how are deoxy forms of uridine and cytidine nucleotides formed in pyrimidine biosynthsis?
    reduction of ribose to deoxyribose
  68. found in cell membranse and contain fatty acids
  69. synthesized then added to other molecules to form other lipids such as triacyglycerols and phospholipids
    fatty acids
  70. what are fatty acids synthsized from
    acetyl-coA, malonyl-CoA, and NADPH
  71. acyl carrier protein
    protein that attaches to intermediates during fatty acid synthesis
  72. how many carbons does the fatty acid synthase add to the carboxyl end at a time
  73. made from fatty acids and glycerol phosphate
    tracyglycerols and phospholipids
  74. major compononets of eucaryotic and bacterial cell membranes
    synthesized from phosphatidic acid