Exam 2 Summary Sheet microbiology

CHAPTER 6 

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6.1 Elements of life o A) Macromolecules  O, H, N, S, P ,C  K, Ca, Mg, Fe, Na+, K+ o B) Micromolecules  Mn, K+, Zn(transcript factor), Co, Mo, Ni, Cu  Make up enzymes and cofactors Table 6.1

MOLECULE Proteins Lipids Carbs Nucleic acids 

Elements CHONS CHOP CHO CHOPN

6.2 o

2 main functions of electrons  Energy (E- move through ETC to provide energy )  Reduce Molecules (in biosynthesis so that they can form organic molec) Carbon Description: Energy Description Electron Description Sources Sources Sources Autotrophs CO2 sole Phototrophs Light Lithotrophs Reduced carbon inorganic esource source Heterotrophs Preformed Chemotrophs Oxidation Organotrophs Organic organic organic or molec emolec inorganic source o

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Cometabolism= digests pesticides. Degraded in presence of growth promoting nutrient that is digested also 6.3 Nutritional Types of Microorganisms o 2 main sources of energy  1) light  2) oxidizing organic or inorganic

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Table 6.3- 5 Major Nutritional Types of Microorganisms NUTRITIONAL TYPE CARBON ENERGY ELECTRON SOURCE SOURCE SOURCE Photolithoautotroph CO2 Light Inorganic

Photoorganoheterotroph Chemolithoautotroph***

Chemolithoheterotroph

Preformed organic C CO2

Preformed Organic C Chemoorganoheterotroph Preformed Organic C

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Light

Organic

Inorganic

Inorganic

Inorganic

Inorganic

Organic ©

Organic

EXAMPLES Cyanobactiera Sulfur bacteria Diatoms Green non sulfur bacteria Nitrifying bacteria Iron-oxidizing bacteria Methanogens Sulfur oxidizing bacteria Sulfur oxidizing bacteria Nonphotosynthetic microbes Pathogenic microbes

o 6.4 Nitrogen, Phosphorus, Sulfur o 3 Main elements necessary for microbial growth  Sulfur, Phosphate, & Nitrogen o Nitrogen  Synthesize amino acid  Can be obtained from either organic or inorganic sources (Nitrate)  Enzymes used: Glutamate dehydrogenase, glutamine synthesis, glutamate synthase (Ch 11)  Processes: assimilatory nitrate reduction & Nitrogen fixation [N2  NH3] (Ch 11) o Sulfur  Nitrogen can be obtained from organic or inorganic sources  Synthesize: methionine & cysteine o Phosphorus  Can only be obtained from inorganic sources, produced in periplasm  o 6.5 Growth Factors o Definition= organic compounds that cannot be synthesized by an organism but are essential for its growth  3 major types growth factors/Cofactors????:  1) amino acids o Used for protein synthesis

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2) purines & pyrimidines o Used for Nucleic acid synthesis  3) vitamins o Small organic molecules that make up coenyzmes NOTE: molec function as coenzymes NOT cofactors o Fun fact: microbes synthesize growth factor: vitamin for human consumption ie: riboflavin, vitamin B12 6.6 Uptake of Nutrients o Bacteria & Archaea take up nutrients via:  1)Facilitated Diffusion  Permeases= carrier proteins, embedded in plasma membrane o Selective o Carrier proteins experience a saturation effect o Only transport closely related solutes o Example: BACTERIA: aquaporins (Claudio says not selective) & ARCHAEA & EUKARYOTES most prominent o No metabolic energy  Diffusion across selectively permeable membrane via carrier proteins  2) active transport o Solute moves against concentration gradient o Used often by microbes o 2 types of active transport proteins:  A) Primary Transporter  Energy from ATP hydrolysis  ATP-Binding Cassette Transporters (ABC transporters) o Uniport= single molecule transported via ABC transporters   B) Secondary Transporter  Energy from PE of ion gradient  Antiport= sodium move out, proton move insubstance move in opposite direction  Symport= proton & lactose simultaneously enter cellsubstance linked move in same direction  3) Group translocation o o Passive Diffusion  High concentration  Low concentration  O2, CO2, H2O move via this method  No metabolic energy required o

CHAPTER 11 

11.1 Principles of Biosynthesis  1) Macromolecules synthesized from limited monomers  Save genetic storage capacity, biosyn raw materials, energy  2) Many have same enzymes for both catabolic & anabolic  Saves materials & energy  3) Some enzymes are irreversible  Allow independent regulation  Although many same enzymes, catabolic & anabolic pathways not identical permits independent regulation  4) Anabolic pathways must operate irreversibly to be efficient  Couple ATP & drive biosynthesis to completion  5) Catabolism & Anabolism are physically separated  only eukaryotes are anabolic/catabolic rxns in separate compartments (since they have membrane bound organelles)  Prokaryotes utilize carboxysomes  6) Catabolism & anabolism use different cofactors  Catabolism: NADH  ANABOLISM: NADPH o Metabolism 2 components:  anabolism  ATP | NADPH | precursor metabolites  synthesize cell components  require energy, use energy from catabolic reactions  catabolism  degrades, produce energy o Supramolecular systems & organelles= macromolecules assemble into supramolecular structures spontaneous via self-assembly (ie: ribosomes)  Prototroph= synthesize own precursor metabolites, bacteria have no nutritional requirement  Auxotroph= special requirements for metabolites, bacteria have 1+ nutritional requirement  11.2 Precursor Metabolites o Central metabolic pathways  Embden Meyerhof  Pentose phosphate  Entner Doudoroff EMP (Embden) PP (Pentose) EDP (Entner) TCA Pentose-5-phosphate Purines & (PP) pyrimidine Purinesvitamins & cofactors Glucose-6-phosphate

Sugar nucleotides

Pentose 5 phosphate

Fructose 6 phosphate

Fructose 6 phosphate Amino sugars

Dihydroxyacetonephosphate

Dihydroxyacetonephosphate Sedoheptulose-7phosphate

Nicotinamide coenzymes & glycerol-3phosophatephospholipids Fructose-6phosphate

Erythros-4-phosphate

Fructose-6phosphate

3-Phosphoglycerate

(3CPHASE) Serine family (tryptophan, glycine, cysteine)

Heptose in LPS Erythros-4phosphate Aromatic family (tyrosine & tryptophan) & vitamins|cofactors (ubiquinone)

Phosphoenolpyruvate Phosphoenolpyruvate Serine family (tryptophan, glycine, cysteine) Pyruvate

Pyruvate family (leucine, alanine)

Acetyl Coenzyme A

Fatty acid, murein, leucine

Oxaloacetate

2-oxoglutarate

Succinyl coenzyme A

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o 11.3 CO2 Fixation via Autotrophs Energetically expensive o 1) Calvin cycle

Oxaloacetate

Acetyl coenzyme A

Asparate Family Methionine Glutamate fam -glutamate -glutamine heme heme

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Reverse of EMP 3ATP & 2NADPH/ 1 CO2 | total: 3x6=18ATP, 2x6=12NADPH, 6 carbons Also called reductive pentose phosphate Archaea don’t use calvin cycle EUKARYOTES= occur stroma BACTERIA= occur carboxysomes 3 phases  1) carboxylation phase  2)reduction phase  3)Regeneration phase CarboxylationReduction PhaseRegeneration Phase

Rubulose 1,5 biphosphate (RuBP)enzyme [split spontaneously to PGA] catalyze CO2  RuBP2 PGA- o o o o o o o 

 2)reductive TCA cycle 3) acetyl-CoA pathway 4)hydroxypropionate cycle 5)???? 6)???