BIO 326R 1st Edition Lecture 6Outline of Last Lecture I. Measuring Growth (contd from last lecture)a. Dry WeightII. Growth in a closed systema. Growth curvei. Lag, log, stationary, deathb. Doubling timec. Closed system vs. continuous cultured. Persister cellse. VBNCIII. Environmental Factorsa. Temperatureb. Osmotic pressurec. Atmospherei. Aerobic, anaerobic, facultative anaerobes, microanerobesOutline of Current LectureI. Metabolisma. Catabolicb. Anabolici. CurrencyII. Catabolic ReactionsThese 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.a. Exergonici. Free energyii. Reduction potentialIII. Anabolic Reactionsa. Endergonicb. Coupled reactionsIV. Enzymesa. Regulation: allosteric and competitive inhibitorCurrent LectureMetabolism= the sum total of all the chemical and physical changes that occur in a living system- Catabolic= breaking things down, releases energy, harvests that energy- Anabolic= building things up, requires energyo Currency for energy ATP NADH/NADPH- Coenzyme= small, organic nonprotein molecule that carries chemical group enzyme- NAD+ + NADP+ NADPHCatabolic Reactions= energy yielding; break down complex substances to low molecular compounds- Protein/enzyme required to break down- Generally oxidative reactions and produce reducing potential- Exergonic= deltaG is negative spontaneous reactiono Reactants>products (energy is released) and delta G<0o Standard Gibbs Free Energy= amount of useful energy that can be extracted froma processo Reduction potential= tendency to lose electrons Ex: NAD + H+ + 2e- NADH- RP= -0.32- Can donate electrons to something with a more positive RPAnabolic Reactions= use harvested energy from catabolic reactions to build molecules- Biosynthetic and require energy- Low molecular weight compound complex/macromolecule- Building blockso Amino acids polypeptides proteinso Sugars peptidoglycano Nucleotides DNA/RNA- Generally reductive in nature and consume energy/RP- Endergonic= need energy, deltaG is positiveo Reactants<products (energy is required) and deltaG>0- Coupled reactions= endergonic and exergonic reactions are linkedo Exergonic (released energy) drives the energonic (uses energy)o End result, net deltaG is negative See slide for coupling reactions for images/equationso Coupling reactions are quick and overall spontaneous (net negative deltaG)Enzymes= proteins that catalyze reactions, specific- Substrateproductso Enzyme name or symbol to represent enzyme goes over the arrow and a star under the arrow means a coenzyme is required- 2 ways to regulate enzymeso Allosteric regulation= small molecule (allosteric effector) binds to a site (NOT the active site) and causes activity of the enzyme to be effected (positively or negatively) Ex: feedback inhibition= in bacteria, histamine biosynthesis—if too much product is made, regulation can occur at any enzyme at any point of the multistep reaction depending on which product is being overproducedo Competitive inhibitor= binds to active site and “out-competes” the substrate to regulate the
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