PART 4 - Kinetics of Substrate Utilization, Product Formation and Biomass Production in Cell Cultures Flashcards
Product Formation, Fermentation, Protein Synthesis
He proposed a scheme, which grouped fermentations according to the manner in which the microbial product appeared in the broth.
Gaden
Product formation is directly
related to carbohydrate
utilization
Fermentation Type 1
Example: Ethanol
Product formation indirectly
related to carbohydrate utilization
Fermentation Type 2
Example: Citric Acid
Product formation apparently not associated with carbohydrate utilization
Fermentation Type 3
Example: Penicillin
Enumerate Gaden’s Classification Scheme for Fermentations
Fermentation Type 1
Fermentation Type 2
Fermentation Type 3
Enumerate Deindoerfer’s Classification of Fermentation Patterns
Simple
Simultaneous
Consecutive
Stepwise
Nutrients converted to products in a fixed stoichiometry without accumulation of intermediates
Simple
Nutrients converted to products in variable stoichiometric proportion without accumulation of intermediates
Simultaneous
Nutrients converted to products with accumulation of an intermediate
Consecutive
Nutrient completely converted to intermediate before conversion to product, or selectively converted to product in preferential order.
Stepwise
Products and their formation can be viewed from several aspects:
(a) as intracellular or extracellular products;
(b) according to the relationship
between the growth rate and the rate of product formation;
(c) according to the stoichiometry of their formation; and
(d) according to the rate of product formation and substrate consumption.
What are the three simple forms of product formation rates?
- Growth-Associated
- Non-Growth-Associated
- Mixed-Growth Associated
____________________ are formed by growing cells
which make them primary metabolites.
Growth – associated products
Non – growth associated products are formed during the _________________ when the growth rate is zero due to the lack of at least one necessary substrate for growth.
stationary phase
These are formed by cells which are not metabolically active, which make them secondary metabolites.
Non-Growth associated products
The ________________________ is considered to correlate the rate of product formation (other than cell mass) with the cell growth rate.
Luedeking – Piret model
It combines growth-associated and non-growth-associated product formation
Luedeking-Piret model
The _________________ associated products include lactic acid fermentation, xanthan gum, and some secondary metabolites from cell culture.
mixed-growth
_______________ models deal with the kinetics of the change in the individual components present in cells.
Structured
An intrinsic concentration is the amount of a compound per __________________________.
unit cell mass or cell volume
Extrinsic concentration, on the other hand, is the amount of a compound per _____________________ which cannot be used in kinetic expressions.
unit reactor volume
Protein synthesis is important in the practice of manufacture of _________, ___________, and other _____________________.
enzyme
hormones
commercial polypeptides
Protein synthesis occurs in two stages:
the transcription and translation
________model is defined as the model that is more likely to give good results when applied to an environment different from where it was originally evaluated.
Robust
______________ is the transfer of the genetic instructions from the DNA to the RNA and it happens in the nucleus.
Transcription
Messenger RNA (mRNA) is produced in the ___________, and it brings genetic information from the ___________________ (usually attached to the endoplasmic reticulum) where translation occurs.
chromosome
chromosome to the ribosomes
During _____________, the transfer RNA (tRNA) brings the specific amino acid from the cytoplasm to the ribosome. Then, the ribosomal RNA (rRNA) which constitutes nearly
65% of the ribosome, helps with the formation of bonds between the amino acids.
translation
_____________ is an isomer of lactose converted through a
secondary activity of β-galactosidase.
Allolactose
The amount of enzyme produced has a direct relationship with the ______________________.
promoter utilization
efficiency.
Therefore, it is also proportional to the probability that the operator site O is not bound by ___________________.
repressor protein R
The parameters in the model have precise physical interpretations and can often be measured in separate, in vitro experiments. Also, models at this level possess what has been called ___________________.
genetic structure
There are two fundamental growth patterns that filamentous
microorganisms may exhibit, depending on the __________________________.
strain and growing conditions:
- Homogenous
- Pellet
Fungi form ___________ composed of cells with distinct differentiated _______ cell.
long hyphae (their filaments)
apical
Although the exact cause of ______________ is yet unknown, mixing mechanical forces are believed to have a significant influence in breaking down homogenous mycelium (mycelium is a network of fungal threads or hyphae) into smaller pieces, which in turn give rise to ______.
pellet growth
pellets
What are the other critical factors of pellet growth?
- The nature or makeup of the medium (clear solutions or suspensions in which solid particles attach to the filament surface)
- the quantity of spores employed to inoculate the medium
Branching is _______ even if the
filaments or hyphae grow ___________.
linear
exponentially
