Living systems Flashcards
what is biotechnology
the use of biological processes to create useful products
What is the process of creating a biotech product from raw materials?
- Raw material upstream processing fermentation downstream processing
examples of biotech products
wine, cheese, vinegar, insulin and citric acid
red biotech?
the pharmaceutical branch which uses bacteria to produce drugs e.g. disease preventation
White biotech?
- White biotech is the aid of living organisms and enzymes e.g. biofuels to biodiseal
Green biotech?
- Green biotech is the use of agriculture such as plants less suspectible to pests e.g. water purification
What is cell growth
essential element of fermentation for the growth of a organism
Growth is an orderly increase of…
cellular constituents
what does optimising the environment for growth require?
balancing the economic feasibility of maintaining a suitable chem environment
What does growth depend on?
the ability to form new protoplasm from the nutrients available
What does cell growth involve
An increase in the cell mass and number of ribosomes and cell division
Methods of measurement of cell mass
- Direct physical measurement of weight after centrifugation
- Direct chemical measurement of chemical component
- Indirect measurement of chemical activity
- Turbidity measurements to determine amount of light scattered by suspension of cells
- Microscopic count
- Viable cell count
Lag phase
after inoculation of cells the population remains unchanged so no cell division occurs but the metabolic activity may increase
expo phase
cells divide by binary fission at constant rate
stationary phase
exhaustion of available nutrients and space growth stops
death phase
population declines
What is a closed system
It is a batch culture where there is a lack of input and output of materials once batch medium has been inoculated, a discontinous process which environment and organisms are changing continually
What is an open system
It is a continous culture which is capable of obtaining steady state where there is balanced input growth substrate and ouput of organisms
equation for increase in cell mass
ln x = ln x0 + n ln 2
*n= t/td, ie no of generations = total time/doubling time
equation for increase in cell mass in terms of specific growth rate
ln x = ln x0 + µt
or 2=exp(ut) doubling
t=generation time
What is a growth limiting substrate
nutrient medium containing one limiting substrate at low concentrations
what limits cell synthesis
nutrient concentration in culture vesssel
Monod kinetics eq for specific growth rate
µ = µmax . s/(Ks + s)
Lineweaver burke plot
slope?
x intercept?
y intercept?
ks/umax
-1/ks
1/umax
plot is /u v 1/s
what is cell yield coefficent
amount of cell mass produced per unit amount of substrate consumed
Yield factor eq
Yfg= - deltaF/deltaG
f= moles produced G= moles consumed
observed biomass yield
Y’xs=-DeltaX/deltaSG
X=biomass produced
SG= mass of substrate
what is a continuous culture
a continuous feed of influent solution containing substrate and nutrients and a drain of effluent solution containing cells and metabolites
what is a chemostat
allows control of rate of growth which can be used to optimise the production of products
What is a primary metabolite
produced at high flow/dilutuion rate stimulating cell growth
What is a secondary metabolite
produced at low flow/dilution maintaining cell numbers
What two parameters are controlled in a chemostat and why?
Dilution rate and influent substrate conc. By controlling the dilution rate we can control the specific growth rate. By controlling the substrate conc we can control number of cells produced or cell yield in chemostat
dx/dt=?
ux-Dx
u=d is steady state
u>D utilization of substrate exceeds supply so slow growth
U
critical dilution eq
Dc=Umax(s/(s+Ks))
Why do we have critical dilution
when a chemostat is operating at Dc , if the dilution rate is increased further, the growth rate will not be able to increase (since it is already at µmax ) to offset the increase in dilution rate.
what is maintence energy
the level of energy required to maintain a cell
purpose of a fermentor
control temp and ph
reduce evapouration
minimise the use of labour
maximise computer control
scales of operation for a fermentor/bioreactor
laboratory 20L
pilot plant 5000L
production 20,000L
Most important factor in fermentor design
height to diameter ratio
why do we implement impellers in bioreactors
to reduce bubble size hence increase surface area for oxygen transfer
What is genetic engineering
the direct manipulation of an organisms genes using biotechnology to change the genetic make up if cells
what is metabolic engineering
the direct improvement of cellular properites through direct modifications of biochem reactions
what are plasmids
self replicating pieces of DNA
what is gene cloning
genes are inserted into a plasmid then added to bacteria for replication
Steps of gene cloning
- Isolate the plasmid
- Isolate gene of interest
- Insert the gene into the plasmid
- Bacteria will take it through transformation
- Cells divide along with the plasmid and form a clone of cells
Why is bacteria grown in a culture
to produce copies of the isolated gene of interest
what is Metabolism
the summation of chemical reactions in a organism
what are autotrophs
organisms that use co2 as their sole carbon
what are chemotrophs
life forms that obtain their energy by injecting carbon
Phototrophs
i.e. plants via sun
Chemotrophs
oxidation of co2 and lipids
anabolism
construction path
Catabolism and how it works
degradation path, it is the breakdown of macromolecules into building blocks then the oxidation of building blocks to produce acetyl coA which is further oxidised to co2 and water