Chapter 3 Flashcards
Macromolecule - Main Function - Main Location
“Carbohydrates/Polysaccharides”
- Backbone of RNA/DNA, energy source, structural
- DNA/RNA backbone, cell wall, storage granules
Macromolecule - Main Function - Main Location
“Fatty Acids/Lipids”
- Structural
- Cytoplasmic membrane, storage granules
Macromolecule - Main Function - Main Location
“Nucleotides/Nucleic Acids”
- Carry genetic information
- DNA/RNA
Macromolecule - Main Function - Main Location
“Amino Acids/Proteins”
- Catalyze reactions, structural
- Flagella, cell walls, cytoplasm
Major morphologies of prokaryotes (6)
- coccus (circle)
- rod (long rectangle)
- spirillum (small twist)
- spirochete (more twists and shorter period)
- budding/appendaged or stalks/hypha (a ball with stick)
- filamentous (random strings)
Major chemical difference between Bacteria membranes and Archaea membranes (3)
- Bacteria: lipid ester linkages – Archaea: lipid ether linkages
- Bacteria: lipids contain fatty acids – Archaea: lipid side chains composed of isoprene units
- Bacteria: always lipid bilayer – Archaea: can be monolayer
Transport systems (3)
- simple transport
- group translocation
- ABC transport
E. coli takes up lactose via lac permease - components of the transport system? source of energy?
Symporter (type of simple tranport, along with uniporter and antiporter)
- membrane-bound transporter protein made of 12 alpha helices
- helices form a channel to transport lactose across the membrane with a proton
- proton motive force
E. coli takes up glucose via phosphotransferase system - components of the transport system? source of energy?
An example of group translocation
- 5 proteins working together
- applicable for glucose, mannose, and fructose transport via phosphorylation
- enzyme I, IIa, IIc, HPr, phophotransferase
- energy from phosphoenolpyruvate (intermediate in glycolysis)
E. coli takes up maltose via ABC transporter - components of the transport system? source of energy?
ATP-binding cassette transporters
- substrate-binding protein (periplasmic binding protein) + membrane-integrated transporter + ATP-hydrolyzing protein
- ATP as energy source
What is peptidoglycan?
A cell wall composed of a polysaccharide backbone of 2 sugar derivatives + 4 amino acids (tetrapeptide)
Glycosidic bonds + crosslinking peptide bonds
What kind of bacteria have outer membrane?
Gram-negative
Chemical composition of outer membrane?
liposaccharides (LPS) + phospholipids + lipoproteins
Functions of outer membrane?
- toxic LPS (endotoxin) - toxicity
- contains porin - help control the transport of small, hydrophilic molecules
- prevent escape of periplasmic proteins
Archaea cell walls has peptidoglycan layer (T/F)
FALSE
What are S-layers made of? Geometry?
- Proteins or lipoproteins
- hexagonal geometry
What is the structure of a bacterial flagellum?
- rotary motor consisting of central rod, L, P, C, MS rings, and basal body
- stator: Mot proteins (generate torque)
What is the energy source of bacterial flagella rotation?
Proton motive force
What is the composition of gas vesicles?
Crosslinked parallel ribs of proteins GvpA and GvpC
What is the function of gas vesicles?
To adjust cell buoyancy
What is the structure of bacterial pilus?
A long, filamentous structure made of proteins (pilin)
What are functions of bacterial pilus?
- transfer DNA between cells
- surface attachment
- type IV twitching motility
