Biochemistry and the Biochemistry and the Genomic RevolutionGenomic Revolution

DNADNA

• Why is DNA in the forefront of Why is DNA in the forefront of modern biochemistry?modern biochemistry?

• What major event involving DNA What major event involving DNA has recently occurred?has recently occurred?

DNADNA

• What do we know about the structure of What do we know about the structure of DNA?DNA?

DNADNA

• What are the bases found in DNA?What are the bases found in DNA?

DNADNA

• Where do we find the genetic Where do we find the genetic information in the DNA molecule?information in the DNA molecule?

• What does a cell do with this What does a cell do with this information?information?

DNADNA

• Why do we refer to DNA as the double Why do we refer to DNA as the double helix?helix?

DNADNA

• What hold the two chains of the helix What hold the two chains of the helix together?together?

DNADNA

• How does the structure of DNA relate to How does the structure of DNA relate to its function?its function?

RNARNA

• How is RNA similar to DNA?How is RNA similar to DNA?• How is RNA different from DNA?How is RNA different from DNA?

RNARNA

RNARNA

• What roles does RNA play in the What roles does RNA play in the cell?cell?– Carrier of genetic informationCarrier of genetic information

• m-RNAm-RNA

– Part of the structure of ribosomesPart of the structure of ribosomes• r-RNAr-RNA

– Carriers of amino acidsCarriers of amino acids• t-RNAt-RNA

ProteinsProteins

• How is the structure of proteins How is the structure of proteins related to the structure of DNA?related to the structure of DNA?

• Why is the genetic code universal?Why is the genetic code universal?• What determines the three-What determines the three-

dimensional shape of a protein?dimensional shape of a protein?

Protein StructureProtein Structure

Unity & Diversity of Living Unity & Diversity of Living OrganismsOrganisms

• What evidence suggests that all What evidence suggests that all organisms are derived from a organisms are derived from a common ancestor?common ancestor?

Unity & Diversity of Living Unity & Diversity of Living OrganismsOrganisms

Chemical BondsChemical Bonds

• Covalent versus non-covalent Covalent versus non-covalent bondsbonds

Non-Covalent BondsNon-Covalent Bonds

• What types of non-covalent bonds What types of non-covalent bonds are there?are there?– ElectrostaticElectrostatic– Hydrogen bondsHydrogen bonds– Van der WaalsVan der Waals

Electrostatic InteractionsElectrostatic Interactions

• E = kq1q2/Dr D=dielectric constantE = kq1q2/Dr D=dielectric constant

Hydrogen BondsHydrogen Bonds

van der Waals interactionsvan der Waals interactions

• Based upon changing electronic charge Based upon changing electronic charge distribution around atomsdistribution around atoms

• Asymmetry of charge of one atom induces Asymmetry of charge of one atom induces complementary asymmetry in neighboring atomscomplementary asymmetry in neighboring atoms

WaterWater

• Why is water so important in Why is water so important in cellular biochemistry?cellular biochemistry?– Major component of most cellsMajor component of most cells– Polar structure make it an important Polar structure make it an important

solventsolvent– Water is a cohesive moleculeWater is a cohesive molecule

WaterWater

• Why does the presence of water Why does the presence of water weaken electrostatic interactions weaken electrostatic interactions between ions?between ions?

• How can the ability of water to act How can the ability of water to act as a solvent cause a problem in the as a solvent cause a problem in the cell?cell?

ThermodynamicsThermodynamics

• What is thermodynamics?What is thermodynamics?– Study of energyStudy of energy

• What does the first law of What does the first law of thermodynamics say?thermodynamics say?– Energy cannot be created nor Energy cannot be created nor

destroyed but may be transformeddestroyed but may be transformed

ThermodynamicsThermodynamics

• What is meant by entropy?What is meant by entropy?• What does the second law of What does the second law of

thermodynamics say?thermodynamics say?– Entropy of the universe is always Entropy of the universe is always

increasingincreasing

ThermodynamicsThermodynamics

Hydrogen on leftOxygen on right

Mixing of hydrogenand oxygenIncrease in entropy

ThermodynamicsThermodynamics

Hydrogen and oxygen combine to form water.Entropy of system decreases but entropy of surroundings increases.

ThermodynamicsThermodynamics

• How do we know whether a How do we know whether a particular reaction will occur particular reaction will occur spontaneously?spontaneously?– Examine Examine G – free energy changeG – free energy change G = G = HHsystemsystem - - TTSSsystemsystem

ThermodynamicsThermodynamics

• What is the hydrophobic effect and how What is the hydrophobic effect and how does it relate to the folding of proteins?does it relate to the folding of proteins?

ThermodynamicsThermodynamics