BIOL 213 1st Edition Lecture 13 Outline of Last Lecture I. Carbon fixationa. 3 CO2 –(9ATP, 6 NADPH, Rubisco) 1 G3PII. Overview of photosynthesis and its interaction with cellular respirationa. A brief review of all the stepsIII. Comparing the proton gradients of mitochondria and chloroplastsIV. Endosymbiotic theorya. Mitochondriab. Chloroplasts Outline of Current Lecture I. DNAa. BlueprintII. Experiments that led to discoveries about DNAa. Frederick Griffithb. Avery, MacLeod, and McCartyc. Hershey-Chase experimentd. Erwin Chargafe. Watson and CrickIII. Properties of DNA double helixIV. Central dogma of biologya. DNA synthesis  transcription to RNA  translation to proteinsThese notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.V. Organization of genomic DNAa. Mitosis b. Chromosomesi. DNA wraps around histones: DNA + histone = nucleosome1. Histone regulationCurrent LectureI. DNAa. Is the blueprint for the whole cellb. Structurei. Double-helix1. Stabilized by van der Waals interactions and hydrophobic interactionsii. Sugar-phosphate backboneiii. Base pairs1. C-Ga. Joined by 3 hydrogen bonds; therefore more stable2. A-Ta. Joined by 2 hydrogen bonds; therefore less stable3. The backbone is held together with covalent bonds whereas the base pairs are held together via hydrogen bondsa. This is why DNA can be “unzipped” – hydrogen bonds are weaker than covalent bondsc. It is a polar moleculei. The end with the phosphate group is 5’ and the end with the sugar is 3’II. Experiments that led to discoveries about DNAa. Frederick Griffith and his studying of pneumococcus (pneumonia)i. Set up1. He had two kinds of pneumonia bacteriaa. S strandi. This bacteria appeared Smooth due to its production of massive amounts of carbohydrates that coated the surface of the cellsii. The carbohydrates proved the bacteria with protection against the hosts immune system: the cells of the immune system weren’t able to grab onto the slippery bacteriab. R strandi. These appeared Rough because they did not produce smooth-looking carbohydratesii. The fact that these did not produce the protective carbohydrate means that they were susceptible to the hosts immune systemii. Results 1. He injected the diferent bacteria into micea. Live S strain: killed the mouseb. Live R strain: mouse livedc. Boiled S strain: mouse livedi. This killed the bacteriad. Boiled S strain + live R strain: killed the mouseiii. What the results mean1. The fact that the mouse died when it was injected with live R strain and dead S strained showed that the dead S strain bacteria was somehow transferring its genetic material that coded for the carbohydrates to the live R straina. This process was called transformationb. Avery, MacLeod, and McCarty experimenti. They furthered Griffith’s results by testing for what the genetic material was that transferred from the S strain to the R strainii. They did this experiment in two diferent ways, both resulting in the sameresult: DNA is the genetic materialiii. Set-up 1: 1. Heat-killed and fractionalized S-strain bacteria into:a. RNAb. Proteinc. DNAd. Lipide. Carbohydrate 2. They added these one at a time to R-strain bacteria to see which one would transfer the information to create carbohydrates3. Only when they added DNA did the R-strain transform to S-strainiv. Set-up 2:1. Heat-killed S-strain bacteria and add specific enzymes to destroy one component at a timea. RNase – breaks down RNAb. Protease – breaks down proteinsc. DNase – breaks down DNAd. Lipase – breaks down lipidse. Amylase – breaks down carbohydratesv. Results1. Set-up 1: adding one thing at a timea. Only when they added DNA did the R-strain transform to S-strain2. Set-up 2: deleting one thing at a timea. Only when they broke down DNA did the R-strain stop transforming into DNAvi. This was more evidence that DNA was the genetic materialc. Hershey-Chase Experimenti. Studied bacteriophages – viruses that attack cellsii. Virus have a protein coat and contain DNA1. They knew that one of these had to contain the genetic materialiii. Labeled the virus DNA with 32P1. DNA has phosphate it the phosphate group of the backbone2. Proteins don’t contain proteiniv. Labeled the virus protein with 35S1. Proteins have sulfur in two amino acids: cysteine and thymine2. DNA doesn’t contain sulfurv. Let the viruses infect the bacteria E. colivi. Put the bacteria and viruses in a blender to take the virus protein coats of the surface of the cell1. A virus coat stays on the cell after they inject the cell with their DNAvii. The mixture is centrifuged to separate the viruses and bacteria1. The supernatant containing the viruses is poured of and the pellet containing the bacteria is rinsed viii. It’s centrifuged again to separate the pieces of bacteriaix. These pieces were analyzed to see if they contained 32P or 35Sx. Found 32P in the mixturexi. This means the DNA was transferred from the viruses to the bacteria1. The 32S was poured out with the viral protein coatsd. Erwin Chargafi. Discovered the variety of DNA in diferent speciesii. Some would have more G and C than A and Tiii. But the amount of A always equaled the amount of T, and the amount of G always equals the amount of Civ. Chargaf’s Rule1. A = T2. G = C3. A + T ≠ G + C e. Watson and Cricki. Discovered the structure of DNA1. Antiparallel strains in a double helix that is stabilized by van der Waals forces and hydrophobic interactionsii. Analyzed the data of Rosalind Franklin1. She used X-ray crystallography to analyze DNA structureiii. They were able to create a 3D double-helix structure of DNA from the crystallographyiv. They figured out that A pairs with T and that G pairs with Cv. They figured out how A pairs with T and that G pairs with C1. The distance of the A-T bonding is the same as the G-CIII. Properties of DNA double helixa. Hydrogen bonds link the base pairs and stabilize the double helixb. 10 bases per helical turnc. Major groovesd. Minor groovese. Each side is complementary to the otheri. This allows replicationf. When a regulatory protein attaches to the DNA, it can slide along the DNA while staying in contact with the base pairsi. The base pair sequence is unique to each gene, so the protein determineswhere it needs to be by what base pair sequence its on ii. IV. Central dogma of biologya. DNA synthesis (replication) [by DNA polymerase] 