- high conc. of Ca2+ and dipicolinic acid (not found in any other biological system) (help with resilience but don't know how) - high number of ribosomes

Lecture 2 Flashcards by Ilana Webb

3 patterns of flagella distribution in a cell

Polar- at one end
Peritrichous- all over
Lophotricious- multiple at one end

How well did you know this?

Not at all

Perfectly

What is a flagellum?

Structure that allows for motility in some orgs

How well did you know this?

Not at all

Perfectly

Regardless of distribution, flagella use a lot of ________ which will cause what to happen?

H+, will deplete H+ that are in H+ gradient, decreases ability of cell to produce ATP

How well did you know this?

Not at all

Perfectly

Describe the speeds of a flagellum

There are no speeds and you cannot turn it off

How well did you know this?

Not at all

Perfectly

Because of massive H+ demand of flagella, what does cell do?

It can “drop” flagella

How well did you know this?

Not at all

Perfectly

Spore details

Highly resistant to temp, desiccation, chemicals, etc.
Form of survival
Occurs in response to stress
Sporulating cell becomes the spore, 1 cell becomes 1 spore
No chromosomal replication, original chromosome gets packaged into the spore
Not metabolically active

How well did you know this?

Not at all

Perfectly

Layers of prokaryotic spore

Exosporium
Spore coat
Cortex
Core wall and core

How well did you know this?

Not at all

Perfectly

Exosporium

Sticky, more likely to be transported, helps with dispersion, can have different chemical compositions

How well did you know this?

Not at all

Perfectly

Spore coat

Contains enzymes that will help with germination

How well did you know this?

Not at all

Perfectly

Cortex

Thick layer of peptidoglycan

ONLY GRAM + can sporulate (not all do)

How well did you know this?

Not at all

Perfectly

Core wall and core

high conc. of Ca2+ and dipicolinic acid (not found in any other biological system) (help with resilience but don’t know how)
high number of ribosomes

How well did you know this?

Not at all

Perfectly

Structure of flagellum

Basal body
Mot proteins
Fli proteins
Support rings embedded in cell layers, anchored in cell wall
Extending out from cell wall or outer membrane, a hook structure
Helical in shape

How well did you know this?

Not at all

Perfectly

Basal body

Flagellum engine located just inside of cell membrane so it can turn flagellum itself and have access to H+

How well did you know this?

Not at all

Perfectly

Mot proteins

Rotate flagellum

How well did you know this?

Not at all

Perfectly

Fli proteins

Determines direction of rotation
Counter clockwise: forward (run)
Clockwise: tumble

How well did you know this?

Not at all

Perfectly

Chemotaxis

Motile cells response to environmental cues
Mostly applies to flagellate motility
Response to enviro cues via series of runs and tumbles; length of runs increase in detection of nutrients

How well did you know this?

Not at all

Perfectly

Examples of taxis

Chemotaxis: response to chemicals
Thermotaxis: response to temp
Phototaxis: response to light

How well did you know this?

Not at all

Perfectly

Surface area to volume ratio

Based on sphere
3/r
Larger cells - less metabolically efficient
Prok. More efficient than euk. Metabolically

How well did you know this?

Not at all

Perfectly

Definition of metabolism

All chemical processes in a cell
2 components:
1. Anabolism: biosynthesis (building cellular materials - requires energy
2. Catabolism - degradation (releases energy)

How well did you know this?

Not at all

Perfectly

Energy molecules in a cell

ATP- assists for breakdown and work

NADPH- used in biosynthesis

How well did you know this?

Not at all

Perfectly

ΔG

Amount of free energy associated with substrate
(-) exergonic - readily give up e
(+) endergonic
Example: ATP ΔG=-7.3 exergonic, used in endergonic reactions

How well did you know this?

Not at all

Perfectly

Eo = reduction potential

(-) likely to release e

(+) likely to accept e

How well did you know this?

Not at all

Perfectly

Energy source classifications

Chemoorganotroph- use organic C for energy (eg. Glucose)

Chemolithotroph- use inorganic electron donors for energy (eg. H, N, S, Fe

How well did you know this?

Not at all

Perfectly

Carbon sources

Heterotroph- use organic C as carbon source (eg. Glucose)

Autotroph- use inorganic C as carbon source (eg. CO2)

How well did you know this?

Not at all

Perfectly

What are the different parts of respiration

Glycolysis, pentose phosphate pathway (PPP), TCA cycle, electron transport chain (ETC)

Two forms of respiration

- aerobic: use O2 as terminal electron acceptor - anaerobic: use something other than O2 as TEA (eg. N, S, Fe, etc.) TEA other than O2 has slower growth

Total energy balance from glycolysis in aerobic respiration

2 ATP 2 NADH --> 6 ATP 8 total

Total energy balance from TCA cycle in aerobic respiration

8 NADH---> 24 ATP 2 FADH2---> 4 ATP 2 GTP ---> 2 ATP 30 ATP

Total ATP produced in aerobic respiration

38 ATP

Pathways in fermentation

Glycolysis, TCA cycle, PPP, fermentation steps

Fermentation steps

Use NADH Use pyruvate from glycolysis End products include alcohols and organic acids

Fermentation

Anaerobic metabolism | No ETC; no H gradient, no ATP production via oxidative phosphorylation

Limitations to fermentation

No oxidative phosphorylation so produce very little ATP Make end products that are toxic to the cell that generated it Reduction in bio synthetic intermediates

Glycolysis intermediates

Glucose-6-phosphate Fructose-6-phosphate Glyceraldehyde 3-phosphate Pyruvate

TCA cycle intermediates and products

Intermediates: Acetyl CoA α-ketoglutarate Oxaloacetate ``` Products 4 NADH/pyruvate 1 GTP 1 FADH2 Biosynthetic intermediates CO2 ```

Pentose phosphate pathway

Starting substrate is glucose-6-phosphate Produces NADPH Produces Biosynthetic intermediates Intermediates Glyceraldehyde-3-P Fructose-6-P Pyruvate

Quinone

Transport electrons

What happens as electrons move down the electron transport chain?

H+ pumped into periplasmic space

What is the terminal electron acceptor in aerobic respiration?

What is the terminal electron acceptor in anaerobic respiration?

Something other than O2

What is the initiator of the electron transport chain in respiration?

NADH dehydrogenase- releases H+ and electrons

Where is the ATPase?

In the cell membrane, has 30 degree rotations

Fermentation steps

Purpose: recycles NADH into NAD+ Unless genetically modified orgs have several pathways Toxic end products eg. Ethanol, lactic acid, propionate Uses pyruvate

Organisms that use chemolithotrophy are

Chemolithoautotrophs: use inorganic source of electrons and CO2 as source of C

Do all chemolithotrophs use chemolithotrophy?

No, some use photosynthesis

Where does the inorganic e donor donate it's es to in chemolithotrophy?

Directly to the ETC, don't need to be shuttled

How are Biosynthetic intermediates made in chemolithotrophy?

Turn CO2 into organic C by the Calvin cycle or reverse TCA cycle

Reverse TCA cycle

3CO2---> pyruvate | Requires energy from NADH or NADPH

Calvin cycle

6CO2 ---> fructose-6-PO4 | Requires 12 NADPH and 18 ATP per cycle

A species will use _____ reverse TCA or Calvin to fix CO2

Either, they do not flip flop

Calvin cycle produces _____, which can go into:

Fructose-6-PO4---> glycolysis--->pyruvate--->TCA cycle Fructose-6-PO4--->glucose-6-PO4--->PPP--->NADPH

Reverse TCA cycle produces _____, which can go into:

Pyruvate---> TCA cycle Pyruvate--->reverse glycolysis--->glucose-6-PO4--->PPP--->NADPH

Chemolithotrophy components

Glycolysis, TCA, PPP, ETC, and Calvin or reverse TCA to fix CO2

In aerobic chemolithotrophy what is the TEA?

In anaerobic chemolithotrophy what is the TEA?

Something other than O2

What is the enzyme responsible for incorporation of CO2 into the Calvin cycle?

RubisCO

Calvin cycle input needs

6CO2 12 ATP 12 NAD(P)H 6ATP

Calvin cycle product

Fructose-6-phosphate

In oxygen if photosynthesis what is each photo system?

An electron transport chain

What is the electron donor in oxygenic photosynthesis?

H2O

What role does light play in photosynthesis?

Stimulator, does not provide energy; it drives energy production

Oxygenic photosynthesis has what that makes it have a stronger gradient?

Photo system I is a second pathway that makes NAD(P)H; producing twice as strong of a gradient

Where are the photosystems located?

Cell membrane because goal is to build H+ gradient

There are more gram ___ that use photosynthesis, why?

Negative because cell wall doesn't retard light as much as a gram positive cell wall would

Anoxygenic photosynthesis uses what as an electron donor and where is it donated to?

Something other than H2O eg. H2S, Fe2+ and to a cytochrome

Anoxygenic photosynthesis uses what to drive the reverse e flow to make ____?

ATP, NADPH

In anoxygenic potosynthesis, NAD(P)H is:

Made but is not the TEA

What organisms use photosynthesis for metabolism?

Chemolithoautotrophs: use inorganic e donor (H2O) and CO2 as C source

How do orgs that use photosynthesis fix CO2?

Reverse TCA | Calvin cycle

What are the 2 types of photosynthesis?

Oxygenic: produces O2; uses H2O as donor Anoxygenic: O2 not produced; H2O not e donor but stil inorganic donor (can only be bacteria and archea)

What pathways do all of the metabolisms include?

Glycolysis, PPP, TCA and all but fermentation have an electron transport chain

Lecture 2 Flashcards

(71 cards)