Exam 2 Quiz 2 Flashcards
Small acid soluble proteins (SASP)
-core pH is 1 unit lower
-will allow DNA to adopt alpha form
-DNA in a cell is beta form
alpha form
wider and more condensed
sporulation
vegetative cell spore
Germination
-spore to vegetative state (1-2 hours)
-lots of scientists dont understand the process
three stages of germination
- activation
- germination
- outgrowth
activation stage
-prepares spores for germination
-germination receptors in inner spore membrane looking for amino acids
-signal degradation of dipicolinic acid and CO2
-temp and flexibility: membrane more fluid to allow activation of germination receptors
germination stage
-spore swells, spore coat ruptures, release of spore components, loss of resistance
-expression of cortex lytic enzyme (CLE)
cortex lytic enzyme (CLE)
complete dehydration of the core
outgrowth stage
-makes new cell components and emerges from the remains of the spore
-begin normal rate of metabolism (uses snaps to kickstart)
-external structures degraded
-binary fission
Nutrition
the process by which chemical substances called nutrients are acquired from the environment and used in cellular activities such as metabolism and growth
two categories of nutrients
- macronutrients
- micronutrients
macronutrients
needed in large quantities: C,O,H,N, S, P, K, Mg2+, Ca2+, Na+, Fe2+, Fe3+
micronutrients
needed in small quantities: heavy metals, Mn, Ni, Zn, Cu
growth factors
organic compounds that are essential cell components or precursor components that cannot be synthesized by the cell
-not considered nutrients
Carbon
-makes up 50% of microbes dry weight
-backbone of all macromolecules
-bacteria can be classified based on carbon source
heterotroph
-gets C from living organisms
-organic compounds
-amino acids, fatty acids, sugars
autotroph
-gets C from environment
-inorganic compounds
-CO2, mineral deposits
Energy
-ability to do work
-have three sources of energy
Three sources of energy
- Organic compounds
- chemoorganotrophs
- inorganic compounds
chemoorganotrophs
-organic compounds
-chemoorganotrophs
Chemolithotrophs
-inorganic compounds: H2, H2S, FeSO4, NH4Cl
Phototrophs
get their energy from light
two types of energy from phototrophs
1.oxygenic photosynthesis
2. Anoxygenic phototsynthesis
Oxygenic photosynthesis is used by…
Cyanobacteria
Anoxygenic photosynthesis has…
no O byproduct
Free energy
The energy available to do work, how much energy can be determined by calculating the change in free energy during the reaction
Negative free energy (delta G)
reaction releases free energy and is exergonic/catabolic rxn
exergonic
release energy
Positive free energy (delta G)
reaction requires energy to proceed and is endergonic/anabolic rxn
endergonic
requires energy, makes something
enzymes
-allow cell chemical rxns to proceed
-usually protein catalysts
catalyst
lowers activation energy of rxn and increases rate of rxn
how do enzymes lower activation energy
-aligns reactive groups
-strain on specific bonds
-creates correct microenvironment
substrates brought together with enzyme
-lock and key model
-induced fit model
what else acts as an enzyme/catalyst?
Ribozymes: RNA molecules as enzymes
properties on enzymes
-increase rxn rates without becoming consumed
-recyclable
-larger in size than substrates
-can be regulated
-affected by temp and pH
What do many enzymes contain?
nonprotein molecules that participate in catalysis but are not substrates
two types of cofactors
- prosthetic groups
- coenzymes
prosthetic groups
-firmly attached
-typically metal ions
coenzymes
-loosely attached
-vitamins
biochemical principles in all living organisms
-catalysis of metabolic reactions by enzymes or ribosomes
-importance of oxidation-reduction rxns to conserve energy
-use of ATP to conserve energy released during most exergonic rxns so it can be sued to drive endergonic rxns
-organization of metabolic rxns into pathways and cycles
oxidation-reduction reactions
energy is released though the transfer of electrons
oxidizes
lose electrons
reduction
gain electrons
standard reduction potential
equilibrium constant for half reactions, measured in volts
negative reaction potential
-half reaction more likely to progress backwards
-donor
positive reaction potential
-half rxn more likely to progress foreword
-acceptor
How are the molecules in half reactions written?
acceptor (+) / donor (-)
what does a large reaction potential mean
more free energy is made available
equation:
delta G = n x f x delta E
delta E
change in the rxn potential (Volts)
n
number of electrons
F
faradys constant (96.5KJ/V)
electron carriers
-typically loosely linked coenzymes
most common coenzyme?
Nicotinamide adenine dinucleotide (NAD+)
NAD+ has
a heteroaromatic ring that accepts protons and electrons more easily
Adenosine Triphosphate
-ATP
-Primary energy currency of the cell
what makes up an energy rich molecule?
-must have a change in free energy more exergonic that -30KJ/mol
-phosphoanhydride
phosphoanhydride
-more energy than phophoester
-energy rich in ATP, ADP, and NOT AMP
Thioester bond
can be energy rich and seen in coenzyme A
Phosphate Level Phosphorylation
-needs ATP synthase to do the work
Aerobic respiration
-catabolic reaction in which organic energy sources are broken down in the presence of oxygen to release energy
-series of three reactions
three reactions of aerobic respiration
- glycolysis
- TCA cycle
- electron transport chain
glycolysis
forms two 3-Carbon pyruvate molecules
TCA cycle
completely breaks down organic compounds releasing CO2
Electron transport chain
chain of membrane associated electron carriers that receive electrons from reduced carriers generated from glycolysis and TCA and donate them to the final electron acceptors and generate ATP along the way
another name for glycolysis
-Embden-Meyerhol-Parnas
starting compound of glycolysis
Glucose (C6H12O6)
Summary of glycolysis
-2 molecules of pyruvate
-4 molecules of ATP are synthesized but 2 molecules were used in the first half so net outcome is net 2 ATP
-2 molecules of NADH
alternative to glycolysis
-Entner-Doudoroff Pathway
Entner-Doudoroff pathway
-typically only in bacteria, specifically gram (-) soil microorganisms
-have differences within the first four steps
