Test 1 - Escheria coli Flashcards
What is its genus? What does it mean for its structure and cell wall?
Escheria; Rod-shaped and Gram -
What is its organization in terms of flagella?
Peritrichous.
What is its class and group? What does its group mean?
Class: Gamma Proteobacteria
Group: Enterobacteria, or bacteria living in gut.
What are 4 other enterobacteria and their pathogenic tendencies?
- sarmolnella - typhod
- shigella - dystntry
- klebsiella - pneumonia
- yersenia : bubonic plague
Is it an aerobe or an anaerobe? What metabolism does it perform?
Facultative Anaerobe. Glycolysis, fermentation, and oxidative phosphorylation.
Explain the flow of phosphate in glycolysis. Remember to include NADH and ATP in explanation.
- Glucose (6 C) –> 1,6 Biphosphate (6 C, 2 P) with 2 ATP usage; Phosphate comes from ATP
- 1,6 Biphosphate (6 C, 2 P) –> 2 glyceraldehyde- 3 Phosphate (6 C, 2 P); Split
- 2 Glyceraldehyde-3 Phosphate (3 C, 2 P) –> 2 1,3-biphosphate (3 C, 4 P); 2 Phosphate comes from cytosol (!!!!) while 2 P is also used in NAD+ to form NADH. This step is missing enzymes, so it seems counterintuitive.
- 2 1,3-biphosphate (3 C, 4 P) –> 2 Pyruvate (3 C) as 4 ADP molecules steal the 4 P from biphosphate to create 4 ATP.
What is the gross output of glycolysis? The net?
Gross: 4 ATP and 2 NADH
Net: 2 ATP and 2 NADH
In glycolysis, _____ _____ is used to power ATP production
inorganic phosphate
What is the NAD+ is for? What is glycolysis also called because of that?
4 phosphate group transfer. Substrate Level Phosphorylation.
In glycolysis, what needs to be replenished? What process does this?
NAD+; Fermentation
There are 3 types of fermentation. E. coli performs…
Mixed Acid Fermentation (all 3 types).
In which fermentations do NAD+ get replenished? In which does it not? Why do organisms bother performing the last process?
NAD+ gets replenished when pyruvate –> lactic acid or Ethanol with CO2.
NAD+ does not get replenished formic acid, CO2, and H2O are produced. This is used only when the buildup of lactic acid, ethanol and/or pyruvate gets dangerous.
In aerobic conditions, E. coli can perform 2 metabolic processes known as…
TCA Cycle and Oxidative Phosphorylation.
In terms of using pyruvate (but NOT in terms of NAD+ replenishment), fermentation is similar to an aerobic process named…
TCA Cycle
In TCA Cycle, what is used, and what is produced? What is the net gain?
Pyruvate is used to produce 3 CO2, 4 NADH, FADH2, and GTP (eventually ATP). Net gain of 1 ATP.
What process uses TCA Cycle’s products, 4 NADH and FADH2?
Oxidative Phosphorylation.
In Oxidative Phosphorylation, the results of FCA Cycle are used for what purpose? What also is used for the same purpose? What drives the final step in ox-pho?
All gets deprotonated to create a [H+] outside the cell. O2 + 4H+ is also used to create 2 H2O and H+ (outside the cell). The final step uses F1/F0 ATPase.
What is the purpose of F1? F0?
F1: proton channel
F0: Makes ATP
Does E. coli grow? How?
Yes, by elongation
Does E. coli develop? How?
No.
How does E. coli reproduce? Explain how the genome gets copied. Explain how the elongated cell becomes 2 cells.
By binary fission. Haploid and circular chromosome gets copied from origin of replication (ori). The “replication bubble” unwinds outwards to crate a Theta structure (looks similar to Greek letter theta), until there are 2 separate circular haploid genomes. PM and CW (Septum) is formed in the middle until it forms 2 separate organisms.
What is Conjugation? What is it not?
Conjugation is transfer of genetic info from one cell to another. It is not replication and not about the cell’s own genetic information.
In conjugation, what is the genetic information called? What does it code for? What does it allow the cell to do?
Episome. Codes for Sex Pillus, thereby making the cell F+ cell, allowing it to propagate the episome more to other F- cells.
How many chemoreceptors do E.coli have? Name one and its attractants.
- Tar Receptor, attracted to aspartine, maltose, Co, and Ni.
