5Tipe Metabolisme Anabolisme - biosintesis Katabolisme - degradasi Pembentukan molekul komplek dari molekul yang sederhanaMemerlukan energi (ATP)Katabolisme - degradasiPemecahan molekul komplek menjadi molekul yang sederhanaMenghasilkan energi (ATP)
8Tasks of metabolic Bringing nutrients into the cell Catabolism convert nutrient into organic compoundBiosynthesis make small molecules from precursor metabolitesPolymerization monomer are chemically polymerized to produce macromolecules (protein, DNA, RNA, peptidoglycan, polysaccharides)Assembly to assemble macromolecules into organel
9What are nutrients that bacteria want? C Sugar, Lipid Energy, BiosynthesisN Protein BiosynthesisO Air Energy
14Struktur Enzim Enzim sederhana – protein saja Enzim konjugasi or holoenzim– protein dan nonproteinApoenzim (bagian protein)Cofactor (bagian nonprotein)cofactor logam – besi, tembaga, magnesiumcoenzim - molekul organik - vitamin
16Enzim menurut lokasi kerja Exoenzim – dikirim ke luar sel (extraseluler), memecah molekul makanan besar atau bahan kimia bahaya; selulase, amilase, penicillinaseEndoenzim – tetap berada dalam sel, dan berfungsi di dalam sel.
27ATP Adenosine Triphosphate Energy currency of the cell Releases free energy when it’s phosphate bonds are brokenAllows cells to do workIt takes work to stay aliveTherefore, without ATP, there is no life
29ATP formation Substrate-level Phosphorylation : During glycolisis/Krebs cycleAdding single phosphate group to ADPPEP + ADP pyruvate + ATPOxidative phosphorylation/Chemiosmosis:by means of ATPaseduring respiration: uses an electrochemical or chemiosmotic gradient of protons (H+) across the inner mitochondrial membrane to generate ATP from ADP
32Formula for Aerobic Respiration C6H12O6 +6O CO2 + 6H2O +38 ATP
33Steps of Aerobic Respiration Glycolysis (glucose oxidation into pyruvate) 2 ATPTransition StepKrebs Cycle (convertion of pyruvate into CO2 & H2 in the presence of O2 or fermentation without O2) 2 ATPElectron Transport (hydrogen is oxidized by oxygen forming water) 34 ATP
34GlycolysisPrimary pathway used by nearly all organisms to convert glucose to pyruvateContain 10 step pathway1 molecule of glucose split into 2 molecules of pyruvateGenerates 2 molecules of ATP and 2 molecules of NADHGlucose (6C) + 2NAD+ + 2ADP +2Pi 2 pyruvate (3C) + 2NADH + 2H+ + 2ATP
40TCA/Krebs CycleNet Yield of Krebs Cycle:1 ATP3 NADH1 NADPH1 FADH2
41Pentose Phosphate Pathway Start with glucose 6-phosphate to phosphoglyceraldehydeAlternate route2 precursor metabolitesNo ATP,2 NADPH (oxidative phae) and Pentose (non-oxidative phase)Glucose 6-phosphate + 2 NADP+ + H2O → ribulose 5-phosphate + 2 NADPH + 2 H+ + CO2
42The primary results of the Pathway are: The generation of reducing equivalents, in the form of NADPH, used in reductive biosynthesis reactions within cells. (e.g. fatty acid synthesis)Production of ribose-5-phosphate (R5P), used in the synthesis of nucleotides and nucleic acids.Production of erythrose-4-phosphate (E4P), used in the synthesis of aromatic amino acids.
44Electron transport system Occurs in cell membraneMakes use of integral proteins called cytochromes,flavoproteins, quinonesSeries of Redox reactionsRequires FADH2 and NADHO2 is final electron acceptorWater is final productATP is produced via oxidative phosphorylation
46Electron Transport Chain As electrons fall from carrier to carrier, energy is used to form ATPThis is done by pumping protons out of the cell as electrons move alongThis creates a proton gradient (proton motive force)Energy represented in this gradient used to synthesize ATP (ATP synthase is used)
48Electron Transport Chain Oxidative phosphorylation in electron transport chain yields:Each NADH generates 3 ATPsEach FADH2 generates 2 ATPs
49Net ATP yield from Aerobic Respiration: Glycolysis: 2 ATP, 2 NADHTransition Step: 2 NADHTCA cycle: 6 NADH, 2 FADH2, 2 ATPElectron Transport Chain:Add all NADH: 10 X 3= 30Add all FADH2: 2 X 2= 38 ATPAdd ATP from above = 4
50Anaerobic Respiration The same as aerobic respiration, generating ATP by phosphorylation, but uses inorganic molecule other than O2 , such as sulfate, nitrate, fumarate as terminal electron acceptorAnaerobic respiration produces less ATP than aerobic respiration
51FermentationFermentation Produces ATP Using an Organic Electron Donors and AcceptorsFermentation is used when oxygen and other alternative electron acceptors are unavailableGenerates 2 ATP by substrate level phosphorylationAlso generates 2 NADH- must be recycled to NAD+Different end products based on which microorganism
54Eukaryotes also perform fermentation, such as the yeast used in alcoholic fermentation to create alcoholic beverages
55Regulation of Metabolism Optimal amount of end productsOnly synthesized enzyme for the best available substrateEfficiency
56Two major types of Metabolic Regulation Genetic level Regulation of gene expression (transcription)Regulates the amount of enzyme or proteinCellular levelRegulates enzyme activityallosteric proteins
57Allosteric different sites Allosteric enzymes- Substrate site- Allosteric site effector site (increase/decrease the rate of enzymatic reaction)Mechanism: change the conformation (shape) of enzyme influence the catalytic site
62Feedback Inhibition (end-product inhibition) End products (effector) bind the enzyme inhibit the its catalytic activityA large amount of end products synthesis slowed downA small amount of end products synthesis speeds up
65Cellular level- metabolic pathway controls through: IsozymesA number of separate enzymes initially carry out the same conversion, each of which is sensitive to inhibition by a different end product.
66The common pathway leading to the synthesis of the aromatic amino acids contains three isozymes. Each of these enzymes is specifically feedback-inhibited by one of the aromatic amino acids. Note how an excess of all three amino acids is required to completely shut off the synthesis of DAHP.
67- Concerted feedback inhibition More than one end product or all end products must be present in excess to repress the first enzyme.
69- Sequential feedback inhibition The common steps are inhibited by the product before the branch, and the first enzyme of each branch is inhibited by the branch product.High levels of P1 and P2 inhibit enzyme E3 and E4, respectively → M3 will accumulate →the pathway is inactivated if both P1 and P2 are high.M1M2M3M4M5P1P2XE3E1E2E4