BIOM-360 Lecture Notes - Lecture 7: Anaerobic Respiration, Citric Acid Cycle, Pyruvic Acid

105 views3 pages
Microbial Metabolism
Metabolism: all chemical reactions in the cell!
Catabolism
Organisms depend on carbon, energy, and electrons to survive and reproduce.
Carbon- autotrophs and heterotrophs
Auto get carbon from CO2 (trees, plants, photosynthetic organisms)
Hetero depend on organic molecules from other organisms (need to eat)
All animals belong to this group.
Energy- phototrophs and chemotrophs
Photo use light as a source of energy.
Chemo undergo oxidation of organic compounds for energy.
Electrons- lithotrophs and organotrophs
Litho are reduced inorganic molecules
Organotrophs
*Know “chemo-” “organo-” “photo-” etc.
Respiration = rxns that convert biochemical energy from nutrients into ATP, involves ETC and an external
final electron acceptor
Aerobic: O2 is final e- acceptor
Anaerobic respiration: final e- acceptor is not oxygen (NO3-, SO4-, CO2, etc.)
Fermentation: use an endogenous final e- acceptor and no ETC, produces less energy
WAY less productive, less ATP produced
If you can’t respire, you may still ferment. Some orgsms can do it all.
Aerobic Respiration
1. Glycolytic pathways (“glycolysis”) glucose to pyruvate
2. TCA cycle from pyruvate to CO2
3. ETC w/ Oxygen as the final e- acceptor (generates most ATP)
Produces ATP and high energy e- carriers (NADH, FADH2)!
Anaerobic Respiration
Uses e- carriers other than O
2
.
Yields less energy
Example: Nitrate as final e- acceptor (depletes soils).
Many microbes are able to switch between aer and anaer resp, depending on O2 availability.
Ability to use both of these = ability to survive.
Fermentation
Does not involve ETC
Different pathways for different products.
Ethanol (alcohol)
Lactic acid (yogurt).
Sometimes, the pathway depends on environmental conditions.
Unlock document

This preview shows page 1 of the document.
Unlock all 3 pages and 3 million more documents.

Already have an account? Log in

Document Summary

Organisms depend on carbon, energy, and electrons to survive and reproduce. Auto get carbon from co 2 (trees, plants, photosynthetic organisms) Hetero depend on organic molecules from other organisms (need to eat) Photo use light as a source of energy. Chemo undergo oxidation of organic compounds for energy. Respiration = rxns that convert biochemical energy from nutrients into atp, involves etc and an external final electron acceptor. Anaerobic respiration: final e - acceptor is not oxygen (no 3- , so 4- , co 2 , etc. ) Fermentation: use an endogenous final e - acceptor and no etc, produces less energy. If you can"t respire, you may still ferment. Aerobic respiration: glycolytic pathways ( glycolysis ) glucose to pyruvate, tca cycle from pyruvate to co 2, etc w/ oxygen as the final e - acceptor (generates most atp) Produces atp and high energy e - carriers (nadh, fadh 2 )! Example: nitrate as final e - acceptor (depletes soils).

Get access

Grade+
$40 USD/m
Billed monthly
Grade+
Homework Help
Study Guides
Textbook Solutions
Class Notes
Textbook Notes
Booster Class
10 Verified Answers
Class+
$30 USD/m
Billed monthly
Class+
Homework Help
Study Guides
Textbook Solutions
Class Notes
Textbook Notes
Booster Class
7 Verified Answers

Related Documents

Related Questions