Unit 2-- Lecture 7 (Microbial Metabolism) Flashcards
All life requires:
Electron flow: to drive all life process
Energy: to move electrons
Materials: to make cell parts
—-nutrients
Macronutrients
Major elements in cell macromolecules
C, O, H, N, P, S
Ions necessary for protein function
Mg2+, Ca2+, Fe2+, K+
Micronutrients
Trace elements necessary for enzyme function
Heterotrophs
Use organic carbon
C-H bonds
Autotrophs
Use carbon dioxide (CO2)
No hydrogens
Phototrophs
Light energy excites electrons
Excited molecules are electron donors
Chemotrophs
Chemicals are electron donors
Oxidation of chemical
Oxidation: donation of electrons (lose)
Reduction: accepting electrons (gain)
OIL RIG
Lithotrophs
Inorganic molecules are electron donors
Organotrophs
Organic molecules are electron donors
Respiration
Inorganic molecules
Fermentation
Organic molecules
Passive Diffusion
Some gases pass freely through membranes
—-O2, CO2
Follows gradient of material
Facilitated Diffusion
Transporters pass material into/out of cell
Follows gradient of material
ABC Transporters (Active Transport)
Use ATP energy to pass material into cell
Transport material against gradient
Symport and Antiport
Gradient of one molecule transports another
—-electron transport creates Proton-Motive Force (PMF)
—-PMF transports other molecules
Transports material against its gradient
Symport: same direction
Antiport: opposite direction
Phosphotransferase System–PTS (Active Transport)
Uses high-energy phosphate to pass material into cell
Modifies material as it enters cell
—-gradient is maintained, pushing material into cell
Catabolism
Breaking down molecules for energy
Anabolism
Using energy to build cell components
Reducing entropy, creating order