Microbiology: Chapter 3

What is pleomorphic?

variable in shape and lack single characteristic form

What characteristic do cyanobacteria have?

filamentous

What do filaments in cyanobacteria allow?

differentiation among cells in filaments

What are heterocyst?

specialized cells within filament, can carry out N fixation

What can myxobacteria sometimes aggregate?

to form structures called fruiting bodies

What shape can Archaea take?

cocci and rods

Are Archaea often single, not clustered?

Yes

What kind of cocci and rods can Archaea take up?

curved rods, spiral shapes, and pleiomorphic

What shapes can Eukarya take up?

Various

What is the average size for Bacteria?

E. coli (1.3 × 4.0 um)

What is the bacterial envelope like inside to outside?

plasma membrane, cell wall, capsule/slime layer/S-layer

Why is gaining nutrition a plasma membrane issue?

Has to pass through and not everything can get through

What are Integral Membrane Proteins?

Both sides of phospholipid bilayer

What are Peripheral Membrane Proteins?

One side of phospholipid bilayer

What things are hydrophilic?

H+ and polar covalent

What things are hydrophobic?

nonpolar covalent bonds

How much of proteins and lipids do PM have?

roughly equal amount

What is Functional Membrane Microdomain?

PM portion comprised of distinct lipids that localizes protein complexes like secretion systems

What do Functional Membrane Microdomain have less motion than?

continously in motion phospholipid bilayer

What are Lipids in Bacterial PM made out of?

phospholipids with small amount of other lipids

What are phospholipids like in the Bacterial PM?

ester linked

What are fatty acid chains like in the Bacterial PM?

unbranched

What are Hopanoids?

similar to cholesterol’s structure

What are Hopanoids more hydrophobic than?

phospholipids

What does a distinct regular bilayer strucuture form in Hopanoids?

functional membrane microdomains

What are Functional Membrane Microdomains?

PM portions compromised of distinct lipids that localizes protein complexes like secretion systems

What are Flotillins?

integral membrane protein that assembles large protein complexes in PM

How does the Functional Membrane Microdomain affects Fluid Mosaic Model?

Organize membrane proteins into specific area that facilitates specific cellular functions

What is the direction of Facilitated Diffusion?

high to low

What is Facilitated Diffusion rare in?

Bacteria

Why does Facilitated Diffusion occur?

Because nutrients are low and need to be able to stockpile

What is the common bacterial form of active transport?

ABC Transporters

What does ABC Transporters stand for?

ATP-Binding Casette Transporters

What are ATP-Binding Casette Transporters?

move substrates such as vitamins, ions, and sugars

What is the direction of Active Transport?

low to high

What is Active Transport rare in?

Bacteria

What is Group Translocation?

Active Transport process where molecule is moved across membrane by carrier proteins while being chemically altered at same time

What is Phosphoenolpyruvate?

sugar phosphotransferase system (PTS)

What does Phosphoenolpyruvate occur in?

many bacteria

What does Phosphoenolpyruvate import sugar while?

phosphorylating them using phospheonolpryruvate (PEP) as phosphate donor

What is PEP?

Common metabolic intermediate

Why is Iron Uptake necessary?

It is needed for E-conserving processes (to make cytochromes) and for function of many enzymes

What are E-conserving processes?

metabolism which involve cytochromes

What are extremely insoluble when taking about Iron Uptake?

Ferric Iron and derivates

When referring to Iron Uptake, what do bacteria secrete?

siderophores

What are siderophores?

small organic molecules that bind ferrie Fe and supply it to cell

What is the PM basic design for Archaeal PM?

2 hydrophilic surfaces and a hydrophobic core

What are Archaeal lipids?

glycerol diethers and diglycerol tetraethers

Are Archaeal lipids an ester-linked phospholipid?

No

How are hydrocarbons like in Archaeal PM?

branched and derived from isoprene units

What do isoprene units change?

how lipids pack together, and fluidity and permeability of membrane

What do isoprene units changing the fluidity and permeability of membrane do?

Allows them to adapt to extreme environments

What are ether links more resistant to than ester links?

chemicla attack and to heat

Can the PM be a mix of monolayers and bilayers?

Yes

What is Lipid 4?

glycerol diether lipid

What is Lipid 4 made out of?

1 glycerol and 2 hydrocarbon chains

What does Lipid 4 form?

Lipid bilayer

What are Lipid 5 and 6?

Diglycerol tetraether lipids

What are Lipid 5 and 6 made out of?

2 glycerol and 2 hydrocarbon chains

What are Lipid 5 and 6 more rigid than?

diethers

How can Lipid 5 and 6 becomes more rigid?

pentcyclic rings are added

What do Lipid 5 and 6 form?

monolayer

What are Lipid 5 and 6 very important in?

very high temp environments

What are microdomains?

Protein clusters that perform specific function and more stable than other PM parts

What kind of environment do Archaea tend to live in?

nutrient poor

What primary transporter system does Archaea use?

ABC Transporters

What secondary transporter system does Archaea use?

symport and anitiport

What is Group Translocatin like for Archaea?

add phosphate to a sugar before transporting

If we cannot grow these in lab, how do we know the transport mechanisms for Archaea?

Sequenced and figured it out

What is the Gram + cell envelope made of?

Thick peptidoglycan cell wall and plasma membrane

What does monoderm mean?

bacteria that have 1 membrane, PM

What kind of bacteria is associated with monoderm?

Gram +

What does the Gram - Cell envelope consist of?

Cell Wall, Plasma Membrane, and Periplasmic space

What does the cell wall consist of in Gram - bacteria?

Outer membrane and Peptidoglycan

What is perplasmic space?

fill up spaces with periplasm

What are diderms?

bacteria that have 2 membranes, PM and outer membrane

What kind of bacteria are associated with diderms?

Gram -

Where is Peptidoglycan present?

In nearly all bacterial cell walls

What kind of structure does peptidoglycan form?

enormous mesh-like structure

What is peptidoglycan sacculus?

refers to the enormous mesh-like structure formed in peptidoglycan

What is the composition of peptidoglycan?

2 sugar derivates

What are the 2 sugar derivates in Peptidoglycan?

NAG and NAM

What are NAG and NAM?

6-C animo sugars

What does NAG stand for?

N-acetylglucosamine

What does NAM stand for?

N-acetylmuramic acid

What is the structure that NAG, NAM, and a peptidoglycan classified as?

Carbohydrate

How id the peptidoglycan sacculus formed?

cross-linking helican strands

What kind of links are made from cross-linking helican strands?

indirect link and direct link

What is the indirect link when referring to cross-linking helical strands in Petidoglycan Sacculus?

Peptide interbridge or interpeptide bridge

What is the peptidoglycan sacculus?

enormous mesh-like structure that is common to nearly all bacterial cell walls

What characterisitcs does peptidoglycan sacculus have?

strong but elastic, porous, and cross-linking can vary

What does being strong but elastic do for peptidoglycan sacculus?

helps with osmotic pressure

What does being porous do for peptidoglycan sacculus?

globular proteins can pass through

For Gram - bacteria, what does having varing amount of cross-linking and connection between peptidoglycan molecules do?

tends to be less cross-linked and use direct linkage

For Gram + bacteria, what does having varing amount of cross-linking and connection between peptidoglycan molecules do?

tend ot be more cross-linked and use interbridges

What does Gram + bacteria have in its cell wall?

Teichoic Acid

What is Teichoic Acid?

negatively charged chains of either ribitol-phosphate or glycerol phosphate w. sugars and animo acids attached

What is the charge of Teichoic Acid?

negative

What are Wall Teichoic Acids?

attached to and extend above peptidoglycan layer

What are lipoteichoic acids linked to?

plasma membrane