BIO357 exam 3 - metabolic processes

catabolism

catabolism

break down molecules

anabolism

building up complex chemical substances from smaller, simpler components

metabolism

balance between catabolism and anabolism

electron transport chain

used to create a proton gradient • coupled transport • movement (power flagella) • make ATP

substrate level phosphorylation

• going from one substrate to another, generating ATP • make ATP based on substrate • Krebs and glycolysis

oxidative phosphorylation

• redox reactions • moving e- via ETC & forming ATP

organo

organic molecules as e- donors for energy

litho

inorganic molecules as e- donors for energy

chemo

chemical reactions yield energy without absorbing light

photo

light reactions yield energy

respiration

• oxidation of e- donors • the oxidant becomes reduced (pulls e- from something else) • using something as a terminal electron acceptor to create a proton gradient

terminal electron acceptor

chemical that is reduced as a consequence of fermentation or respiration (TEA)

aerobic respiration

uses oxygen as the terminal electron acceptor

anaerobic respiration

uses something other than oxygen as the terminal electron acceptor

assimilation

incorporation of materials into biomass

dissimilation

used to make energy

examples of dissimilation

• nitrate reduction • sulfate reduction • iron reduction • methanogenesis

examples of assimilation

• amino acid biosynthesis • carbon fixation

hydrogenotrophy

• the use of molecular hydrogen as an electron donor • creates Na+ gradient (used similarly to H+ gradient)

methanogenesis

CO2 + 4H2 → CH4 + 2H2O • need lack of O2 gas

bacteriorhodopsin and proteorhodopsin

pigments in bacteria used to create H+ gradient → ATP

cyanobacteria

can do photosynthesis and nitrogen fixation

RuBP carboxylase

• enzyme that starts the Calvin cycle • most prevalent enzyme on the planet

reverse TCA cycle

uses ATP to make oxaloacetate/acetyl CoA and fix carbon

denitrification

NO3/NO2 → N2

nitrification

NH4+ → NO3/NO2

molybdenum

nitrogenase's cofactor

dealing with oxygen

• make enzymes to protect • make heterocysts • fix N2 at night

homolactic fermentation

glucose → pyruvate → lactic acid (cheese + sausage)

heterolactic fermentation

pyruvate → lactic acid + ethanol + CO2 (sauerkraut/or any vegetable)

ethanolic fermentation

pyruvate → ethanol + CO2 (bread and alcohol)

curd

a soft, white substance formed when milk sours, used as the basis for cheese

whey

the watery part of milk that remains after the formation of curds

norovirus

• most common cause of diarrhea • lasts 1-2 days • vomiting, diarrhea, abdominal pain; headache and low-grade fever

salmonella

• most common food-borne cause of death • gastrointestinal disease that includes diarrhea, fever, and abdominal cramps last in 4-7 days • fatal cases most common in immunocompromised patients

campylobacter

• usually causes severe bloody diarrhea, fever, and abdominal cramps lasting 7 days • fatal cases most common in immunocompromised patients

E. coli O157:H7

• usually causes severe bloody diarrhea and abdominal cramps lasting 5-7 days • ~5% develop hemolytic uremic syndrome, in which red blood cells are destroyed and the kidneys fail

clostridium botulinum

botulinum toxin causes progressive paralysis with blurred vision, drooping eyelids, slurred speech, difficulty swallowing, and muscle weakness

saccharomyces cerevisiae

baker's and brewer's yeast

embden-meyerhof-parnas pathway

another name for glycolysis

glycolysis input

glucose, 2 ATP, 2 NAD+

glycolysis output

2 pyruvate, 4 ATP (net 2), 2 NADH

entner-doudoroff input

sugar, 1 ATP

entner-doudoroff pathway

• produces NADPH and ATP • does not involve glycolysis

entner-doudoroff output

2 ATP (net 1), NADH, NADPH, 2 pyruvate

pentose phosphate input

glucose

pentose phosphate pathway

a metabolic process that produces ribulose-5-phosphate for biosynthesis

glycolysis

the breakdown of glucose by enzymes, releasing energy and pyruvic acid

pentose phosphate output

ribulose-5-phosphate, 1 ATP (net), NADPH, 1 CO2

fermentation purpose

• regenerate NAD+ • remove pyruvate (if too much accumulates, shuts off glycolysis) • does NOT make ATP directly • independent of oxygen

krebs cycle

second stage of cellular respiration, in which pyruvate is broken down into carbon dioxide in a series of energy-extracting reactions

krebs input

acetyl CoA/pyruvate

krebs output

3 CO2, 4 NADH, 1 FADH2, 1 ATP (GTP)

krebs purpose

• get rid of pyruvate (in the form of CO2) • allows for production of more energy • making NADH and FADH2 (electron carriers)

calvin cycle

reactions of photosynthesis in which energy from ATP and NADPH is used to build high-energy compounds such as G3P

calvin cycle input

3 CO2, ATP, NADPH

calvin cycle output

G3P

reverse TCA input

CO2 and 4-5 ATP

reverse TCA output

oxaloacetate or acetyl CoA (gluconeogenesis)

nitrogen fixation

N2 → NH4+/NH3

actetyl coA pathway

2 CO2 → acetyl coA

food spoilage

• acidity → sour taste • rancidity • putrefaction • alkalinity → bitter taste • toxic pathogens → food poisoning

rancidity

oxidation of fats

putrefaction

protein breakdown

fermentation benefits

• prebiotic/probiotic • better preservation • removes infectious microbes • easier to digest (pre-chewed) • more nutrients available

curd formation

• fermentation by bacteria and/or rennet (enzymes) • ↓ pH → proteolytic cleavage → firm/solid • ↓ pH → kills microbes

pasteurization

milk: 63°C for 30 min, quick cool to 4°C

canning

food preservation method in which food is cooked under pressure to attain temperature high enough to destroy endospores (~121°C)

dehydration methods

• freezing • drying • freeze-dry • salting • sugars (drying out fruits)

industrial microbiology

• use of microbes to manufacture things such as vaccines/drugs, human proteins, and organic compounds • cost effective • large scale production • easy to harvest • safe (non-disease causing)

pyruvate to ethanol

pyruvic acid → acetaldehyde (CO2 byproduct) → ethanol (NADH → NAD+)

pyruvate to lactic acid

pyruvic acid + NADH → lactic acid + NAD+

pyruvate to acetic acid

pyruvic acid → acetyl coA → acetic acid + coA

alkaline fermentation

• ↑ protein foods • ↑ pH • mostly release of NH3 (break down fats and proteins)