Bchs 3304 1st Edition Lecture 1Current LectureBiochemistry is the study of the chemistry of life. Biochemistry is an interdisciplinary science overlapping with chemistry, cell biology, genetics, immunology, microbiology, pharmacology, and physiology. Primary Questions in Biochemistry Chemical and three-dimensional structures of biological molecules?How do biological molecules interact with each other?How does the cell synthesize and degrade biological molecules? How is energy conserved and used by the cell?What are the mechanisms for organizing biological molecules and the coordinating of their activities?How is genetic information stored, transmitted, and expressed?Prebiotic World~4.6-5.3 billion years ago Earliest known fossil is ca. 3.5 billion years ago (filamentous bacterium)Most organisms are ca. 70% water Living matter consists of a small number of elementsElemental composition of the human body (97%) Trace: B, F, Al, Si, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Br, Mo, Cd, I No direct fossil record of prebiotic conditions! Possible early atmosphere consisted of H2O, N2, CO2, small amounts of CH4, NH3 Sparking of a mixture of CH4, NH3, H2O, and H2 for 1 week yieldedAcids (formic, glycolic, lactic, propionic, acetic, succinic, aspartic, glutamic, etc.) Amino Acids (glycine, alanine, aspartic, glutamine) Others (urea, sarcosine, N-methy-alanine, N-methyl-urea, etc.)Biological molecules were created underwater at hydrothermal vents that emit metal sulfides solutions at 400C. Chemical EvolutionMany enzymes catalyze hydrolysis and condensation reactions Hydrolysis = water breaking Condensation = assembling together In particular, the condensation reaction has been very useful throughout evolution for increasing biological complexity. Of course, the hydrolysis carries out the reverse reaction, leading to a loss in biological complexity. Complementarity enables replication through templating (e.g., COO-… NH4+) Base complementary in DNACellular ArchitectureCompartmentation= sequestering into a compartment (vesicle) These entities would have had the ability to shield self-replicating chemical reactions and catalyzed reactions so that they were taking place in a sheltered environment, higher concentration of nutrients and ions, giving them a competitive advantage. Catalyst is a substance that promotes a chemical reaction. Prokaryotes and Eukaryotes Prokaryotes: lack a nucleus (e.g., bacteria, archaea): 1 to 10 uMEukaryotes: membrane enclosed nucleus encapsulating their DNA (e.g., animals, plants, fungi): 10 to 100 uMViruses are not cells and are not defined as living since they lack the apparatus to reproduce outside of their host cells. Aren’t considered living because if you put on your paper then it will die. Eukaryote compartmentation extends to the other cellular structures: Endoplasmic reticulum, mitochondria, golgi apparatus, lysosomes, etc. Mitochondria= place of metabolism Taxonomy: biological classification Phylogeny: evolutionary history Principles of EvolutionEvolution is not goal directedProceeds via random changes called mutation. Organisms that are better suited to reproduce in their environment flourish. Evolution requires some built-in sloppiness. This is a source of mutation. Evolution is constrained by it’s past. The new arises from the oldEvolution is ongoingNot always toward increasing complexity. Thermodynamics- First LawEnergy (U) is conserved- it can be neither created nor destroyedThe Enthalpy (H) of a process is defined as follows: Entropy (S) is the measure of the degree of disorder in a system, often related to number of states a system can adopt. + increase of Entropy, - decrease of entropy Gibbs Free Energy (G) It’s the change of a spontaneous process is