Lecture 2: Microbial physiology and metabolism Flashcards
What macromolecules are required for cell components?
a. C
b. O
c. N
d. S
e. P
What trace elements are required for cell components?
a. Mn, Zn, Co, Mb, Ni, Cu
This organism uses light as energy
Phototrophs
This organism uses the oxidation of organic or inorganic compounds
Chemotrophs
These organisms use reduced inorganic molecules
Lithotrophs
These organisms use organic molecules
Organotrophs
These organisms use CO2 mainly
Autotrophs
These organisms use reduced, preformed organic molecules (carbon)
Heterotrophs
How do organisms get their Nitrogen source?
Ammonia nitrate → ammonia
What lifestyle do all organisms engage in?
Chemoorganotrophic heterotrophy
These perform anaerobic respiration and fermentation
Strict anaerobes
These perform aerobic respiration only
Strict aerobes
Strict aerobes have what final electron acceptor?
Oxygen
What is the final electron acceptor for strict anaerobes performing fermentation?
Organic molecules
What is the final electron acceptor for strict anaerobes performing anaerobic respiration?
Inorganic molecule
Facultative anaerobes can perform what?
Respiration and fermentation
The cytochrome d branch on E. coli is what phase?
Low aeration, stationary phase
What is the most medically relevant bacteria?
Facultative anaerobes
The cytochrome O branch on E. Coli is what phase?
High aeration, log phase
These have a special CO2 requirement
Capnophilic
This moves from higher concentration to lower concentration
Facilitated diffusion
Does facilitated diffusion have an energy requirement?
No
These are carrier proteins that are embedded in the plasma membrane that aid in facilitated diffusion
Permeases
Is the rate of transport faster for facilitated or passive?
Facilitated diffusion
These are transported substances that are ALTERED chemically during the process
Group translocation
This is when energy is used to drive the accumulation of a substance, which remains UNCHANGED by the transport process
Active transport
What energy and system does group translocation use?
a. PEP
b. Phosphotransferase system
What kind of active transport systems are there?
a. Ion-driven
b. Binding protein-dependent
This active transport system uses proton motive force by coupling to an energetically unfavorable transport event
Ion-driven transport system
What are common substances transferred by the ion-driven transport system?
Amino acids
This active transport system, use membrane proteins that form a channel and drive substance through the channel and drive substances through the channel using the energy from ATP hydrolysis
Binding protein-dependent
- What are the common substances transferred by the binding-protein dependent system?
a. Sugar
b. Amino acids
Is ferric iron soluble or insoluble?
Insoluble
What do microorganisms use to aid in iron uptake?
Siderophores
These are organisms that have complex needs and can only grown in association with the human body or in a complex culture medium
Nutritionally fastidious
What is an example of a organism that requires complex needs or a complex culture such as BLOOD AGAR?
a. Staphylococci
b. Streptococci
What is an example of a bacteria that is a obligate intracellular parasite?
Chlamydia
What are the stages of microbial growth and resting states?
a. Lag
b. Exponential
c. Stationary
The result of regulation is that pathways can be
a. Switched on and off
b. Be turned up or turned down
How is control established?
a. Control of enzyme activity
b. Control number of enzyme molecules
Allosteric sites bind regulatory molecules that are
a. Noncovalent
b. Reversible
c. Affects the activity of the enzyme
This is when an enzyme is not bound to the active site but to a different site for regulation?
Allosteric regulation
A cell has abundant levels of leucine and, as a consequence, decreases the production of an enzyme for leucine biosynthesis by terminating transcription of the mRNA for the enzyme after it has already started. The mechanisms involves ribosomes read-through of a small open reading
fram at the 5’ end of the mRNA that results in creation of a transcription structure in the mRNA.
This is an example of
Attenuation
Allosteric regulation directly affects what?
a. Change affinity of the enzyme for substrate
b. Changes in vmax
This increases initiation of TRANSCRIPTION of the mRNA region
Gene induction by an inducer
Attenuation occurs in what region of enzyme synthesis, does what, and what molecule?
a. mRNA
b. Terminates transcription is abundant leucine or starts if no leucine
c. Leucine
The lac repressor protein does what?
Blocks transcription for the coding region
These help block transcription by placing a protein next or the operator site
Gene repression by a corepressor
What does an inducer do?
Blocks the lac repressor protein allowing for transcription
A cell has abundant levels of tryptophan and, as a consequence, decreases the production of an
enzyme for tryptophan biosynthesis by preventing the initiation of transcription of the mRNA for
the enzyme. This is an example of
Gene repression by a corepressor
