Advanced Cell Biology. Lecture 7

Advanced Cell Biology. Lecture 7

Advanced Cell Biology. Lecture 7 Advanced Cell Biology. Lecture 7 Alexey Shipunov Minot State University January 27, 2012 Advanced Cell Biology. Lecture 7 Outline Questions and answers Nucleic acids Structure Other nucleic acids Macromolecules in cells Cells and energy Advanced Cell Biology. Lecture 7 Outline Questions and answers Nucleic acids Structure Other nucleic acids Macromolecules in cells Cells and energy Advanced Cell Biology. Lecture 7 Outline Questions and answers Nucleic acids Structure Other nucleic acids Macromolecules in cells Cells and energy Advanced Cell Biology. Lecture 7 Outline Questions and answers Nucleic acids Structure Other nucleic acids Macromolecules in cells Cells and energy I TAACCTTCG I DNA Advanced Cell Biology. Lecture 7 Questions and answers Previous final question: the answer Write a sequence complementary to ATTGGAAGC Is it from DNA or RNA? Advanced Cell Biology. Lecture 7 Questions and answers Previous final question: the answer Write a sequence complementary to ATTGGAAGC Is it from DNA or RNA? I TAACCTTCG I DNA Advanced Cell Biology. Lecture 7 Nucleic acids Structure Nucleic acids Structure Advanced Cell Biology. Lecture 7 Nucleic acids Structure Hydrogen bonds in complementary strands Advanced Cell Biology. Lecture 7 Nucleic acids Structure Double helix I DNA form helical structure where phosphate and sugar form “envelope” and bases form a “core” I Two grooves: major and minor Advanced Cell Biology. Lecture 7 Nucleic acids Structure DNA double helix Advanced Cell Biology. Lecture 7 Nucleic acids Structure DNA double helix from top Advanced Cell Biology. Lecture 7 Nucleic acids Structure Sequences, ends, abbreviations I Since nucleotides are complementary, it is usually only one strand listed I Each strand has 3’ (–OH) and 5’ ends (phosphate) Advanced Cell Biology. Lecture 7 Nucleic acids Structure 3’ and 5’ ends Advanced Cell Biology. Lecture 7 Nucleic acids Structure Abbreviations for nucleic acids components Advanced Cell Biology. Lecture 7 Nucleic acids Structure Abbreviations for nucleotide sequences Advanced Cell Biology. Lecture 7 Nucleic acids Structure Nucleotides and UV light Advanced Cell Biology. Lecture 7 Nucleic acids Other nucleic acids Nucleic acids Other nucleic acids Advanced Cell Biology. Lecture 7 Nucleic acids Other nucleic acids ATP I ATP (adenosine-triphosphate) is coenzyme (ferment helper), derivative of ribose, adenine and three phosphoric acids I Contain two highly energetic bonds Advanced Cell Biology. Lecture 7 Nucleic acids Other nucleic acids ATP Advanced Cell Biology. Lecture 7 Nucleic acids Other nucleic acids ATP movie ATP movie Advanced Cell Biology. Lecture 7 Nucleic acids Other nucleic acids NADP I NADP, nicotinamide adenine dinucleotide phosphate is a coenzyme, derivative of adenine I Typically, used as hydrogen carrier I Has a medical name “vitamin B3” Advanced Cell Biology. Lecture 7 Nucleic acids Other nucleic acids NADPH Advanced Cell Biology. Lecture 7 Nucleic acids Other nucleic acids Other nucleotide coenzymes I FAD, flavin adenine dinucleotide, vitamin B2 I CoA, coenzyme A, vitamin B5 I Both are extremely important for cell respiration Advanced Cell Biology. Lecture 7 Nucleic acids Other nucleic acids FAD Advanced Cell Biology. Lecture 7 Nucleic acids Other nucleic acids CoA Advanced Cell Biology. Lecture 7 Macromolecules in cells Most frequent macromolecules I Polymer molecules generate most of cell dry weight (30% of total weight) I Proteins are 15%, nucleic acids 7%, lipids and polysaccharides 2% each Advanced Cell Biology. Lecture 7 Macromolecules in cells Noncovalent bonds, conformations and binding I Non-covalent bonds are responsible from shaping of macromolecules I Almost every macromolecule has different shaping variants—conformations I Intermolecular binding is also due to noncovalent bonds Advanced Cell Biology. Lecture 7 Macromolecules in cells Types of noncovalent bonds I Hydrophobic forces I Van der Waals attractions: due to fluctuation of electric charges I Electrostatic, including hydrogen Advanced Cell Biology. Lecture 7 Macromolecules in cells Binding with noncovalent (electrostatic) bonds Advanced Cell Biology. Lecture 7 Cells and energy Metabolism I Metabolism is the sum of all chemical reactions in living organism I Catabolism is the part of metabolism responsible for degrading complex molecules I Anabolism is the opposite part Advanced Cell Biology. Lecture 7 Cells and energy Metabolism Advanced Cell Biology. Lecture 7 Cells and energy Second law of thermodynamics I Thermodynamic definition (Rudolf Clausius): No process is possible whose sole result is the transfer of heat from a body of lower temperature to a body of higher temperature. I Simplistic definition: In isolated system, disorder is always increasing I To revert initial order, energy should be spent I Generally speaking, entropy is a measure of disorder (better—measure of randomness) δQ I In strict sense, entropy is dS = T , where Q is amount of heat and T —absolute temperature (constant) Advanced Cell Biology. Lecture 7 Cells and energy Entropy Advanced Cell Biology. Lecture 7 Cells and energy Triumph of entropy: “post-apocalyptic world” Advanced Cell Biology. Lecture 7 Cells and energy Entropy explained: energy tube Advanced Cell Biology. Lecture 7 Cells and energy Different forms of energy I Mechanical energy: potential and kinetic I Heat energy I Electromagnetic energy I All forms are inconvertible; and first law of thermodynamics says that energy never disappears, it only changes its form Advanced Cell Biology. Lecture 7 Cells and energy Photosynthesis I The way of transforming light energy to energy of chemical bonds I The schematic description is: light energy + CO2 + H2O ! sugars + O2 + heat energy I Part of anabolism Advanced Cell Biology. Lecture 7 Cells and energy Cellular respiration I Almost opposite process I Schematic description: sugars + O2 ! CO2 + H2O + chemical energy (ATP) I Part of catabolism Advanced Cell Biology. Lecture 7 Cells and energy Oxidation and electron transfer I Cellular respiration is based on oxidation, taking electrons off I Converse reaction is reduction; together they are redox reactions I For organic molecules, typical oxidation sequence is: carbohydrates ! alcohols ! aldehydes ! organic acids ! CO2 Advanced Cell Biology. Lecture 7 Cells and energy Enzymes and energy of activation I Most of processes need the energy of activation I Enzymes could lower activation barriers Advanced Cell Biology. Lecture 7 Cells and energy Energy of activation Advanced Cell Biology. Lecture 7 Cells and energy Catalysis movie Advanced Cell Biology. Lecture 7 Cells and energy Enzyme terminology: catalysis and substrate I Enzyme binds with substrate, I then catalyze conversion of substrate into product, I and returns untouched to the initial state Advanced Cell Biology. Lecture 7 Cells and energy Catalysis terms Advanced Cell Biology. Lecture 7 Cells and energy Enzyme performance I Two numbers are using for measuring enzyme performance: Vmax and KM I Vmax is maximal available reaction rate I KM is the concentration of substrate when the rate is Vmax=2 Advanced Cell Biology. Lecture 7 Cells and energy Enzyme performance How living organisms are working against the second law of thermodynamics? Advanced Cell Biology. Lecture 7 Cells and energy Final question (3 points) Advanced Cell Biology. Lecture 7 Cells and energy Final question (3 points) How living organisms are working against the second law of thermodynamics? Advanced Cell Biology. Lecture 7 Cells and energy Summary I The second law of thermodynamics is about increasing entropy I All metabolic reactions need energy Advanced Cell Biology. Lecture 7 Cells and energy For Further Reading A. Shipunov. Advanced Cell Biology [Electronic resource]. 2011—onwards. Mode of access: http: //ashipunov.info/shipunov/school/biol_250 B. Alberts et al. Essential Cell Biology. 3rd edition. Garland Science, 2009. Chapter 2, Chapter 3: 58–100..

View Full Text

Details

  • File Type
    pdf
  • Upload Time
    -
  • Content Languages
    English
  • Upload User
    Anonymous/Not logged-in
  • File Pages
    51 Page
  • File Size
    -

Download

Channel Download Status
Express Download Enable

Copyright

We respect the copyrights and intellectual property rights of all users. All uploaded documents are either original works of the uploader or authorized works of the rightful owners.

  • Not to be reproduced or distributed without explicit permission.
  • Not used for commercial purposes outside of approved use cases.
  • Not used to infringe on the rights of the original creators.
  • If you believe any content infringes your copyright, please contact us immediately.

Support

For help with questions, suggestions, or problems, please contact us