Microbial Biotechnology Flashcards
What are FOUR common industrial biotechnology strains?
- E. coli
- B. subtilis
- S. cereviseae
- A. niger
What bacterial strain is used in products to treat IBS?
Bifidobacterium longum
What yeast strain is used to make Quorn?
Fusarium venenatum
What is the Metagenome?
The collective genomes of an assemblage of microorganisms
What are the steps in Metagenomic Screening?
- Isolate combined DNA
- Chop it up
- Clone fragments into a suitable vector
- Transform into a suitable host strain
What are the steps in Sequence-Based Screening?
- Sequencing of metagenomic DNA
- Gene prediction
- Gene annotation
- Primer design and amplification
What are the steps in Sequence-Based Screening?
- Sequencing of metagenomic DNA
- Gene prediction
- Gene annotation
- Primer design and amplification
What are the steps of Function-Based Screening?
- Construction of metagenomic library
- Activity detection
- Isolation and sequencing of positive clones
How many species of microbes are known?
5000
What is the percentage of microbial cells in the body?
90%
What is the percentage of microbe from the Earth’s biomass?
60%
How many prokaryotic cells are there on Earth?
4-6 x 10^30
How many bacterical cells are there in a gram of soil?
10^9
How many bacteria are there per ml of ocean water?
10^6
What is the total number of bacteria are there in the marine environment?
3.67 x 10^30
What is the percentage of microbes in seawater that can be cultured?
0.001 - 0.1%
What was the first antibiotic to be discovered and by who?
Penicillin discovered by Fleming in 1928
From what fungal strain is Penicillin produced?
Penicillium notatum
(Now Penicillium chrysogenum used)
What bacterial strain does Penicillin inhibit?
S. aureus
What is a mould?
A fungus that grows in the form of multicellular filaments called hyphae
Name FIVE commercially significant secondary metabolites used as antibiotics
- Streptomycin
- Tetracycline
- Chloramphenicol
- Kanamycin
- Neomycin
What antibiotics inhibit cell wall synthesis?
Beta lactams (penicillin, cephalosporin), Vancomycin, Bacitracin, and Polymyxin (membrane)
What antibiotics inhibit nucleic acid synthesis?
- Sulfonamides and Trimethoprim (folate synthesis
- Quinolones (DNA gyrase)
- Rifampin (RNA polymerase)
What antibiotics inhibit protein synthesis?
- Macrolides & Chloramphenicol (50S)
- Tetracycline & Aminoglycoside (30S)
How is antibiotic resistance spread in humans?
- A person develops resistance in the gut and then it spreads to the general community
OR
- In hospital, resistant microbes spread directly to other patients
How is antibiotic resistance spread in animals?
Animal develops resistance, drug-resistant bacteria remain on meat, and if not cooked/handled properly it can spread to humans.
What is the “Perfect Storm” of antimicrobial resistance?
Companies pulling out of antibiotic research and fewer antibiotics are discovered due to AMR
Where does Penicillin production take place?
In a fermenter / bioreactor
What are the THREE typical requirements for producing Penicillin in a bioreactor?
- Aseptic operation
- Agitation & aeration
- Measurement & control
What are the THREE possible products after yeasts / moulds being in a production fermenter?
- Compressed yeast cakes
- Active dry yeast
- Nutritional dry yeast
What is a fermenter / bioprocessor / bioreactor?
A vessel and ancillaries which has been designed to facilitate the growth and/or activities of microorganisms under controlled and monitored conditions
What is the size of a bioreactor for diagnostics enzymes production?
1000-20,000 litres
What is the size of a bioreactor for antibiotic and some enzyme production?
40,000-80,000 litres
What is the size of a bioreactor for penicillin production?
100,000-150,000 litres
What is the size of a bioreactor for amino acid, beer, and wine production?
200,000-500,000 litres
Does penicillin production need oxygen?
Yes
What does agitation in the fermenter provide?
Uniform, controllable conditions and avoids nutrient depletion and product build up
What does aeration in the fermenter ensure?
Oxygen supply to all cells
What are the FOUR phases of microbial growth?
- Lag phase
- Acceleration/Log phase
- Stationary phase
- Death phase
What is the second stage for penicillin commercial production?
Innoculum
What are THREE culture storage methods?
- Refrigeration (2-6°C)
- Lyophilisation (freeze dry)
- Frozen storage (-18°C to -80°C)
What is the kill rate of frozen storage?
95%
What is the temperature range of glycerol suspensions?
-80°C to -196°C
Which phase does PRIMARY metabolism occur?
Trophophase (Lag & Acceleration phase)
Which phase does SECONDARY metabolism occur?
Idiophase (Stationary & Death phase)
What are Point Mutations?
Any mutation where only a single base of the DNA is affected (most common type)
What are Frameshift Mutations?
Addition or Deletion of one or two base pairs
What are the THREE typical effects of frameshift in a transitional region?
- Destroys encoded product function due to loss of reading frame
- Discloses nonsense signals and may have polar effects
- May be restored by nearby compensatory frameshift
What are Chromosome Mutations?
Change in the order or location of genes
How do Chromosome Mutations change the order or location of genes?
- Deletion
- Disruption
- Duplication
- Translocation
- Amplification
- Inversion
What are the essential requirements for bioreactors that also reflect important physiochemical aspects of microbes?
- Maintain sterility
- Homogeneity
- Low shear forces
- Thermal stability
- Suspend solids
- Gas exchange (oxygen)
What is the advantage of metabolic versatility?
Diverse arrays of reactions possible
What is the major motivation for industrial strain improvement?
Economic
What was the output for the original penicillin production strain and the mutated one in g/L?
0.01 g/L
After mutation based strain development it becomes >7 g/L
What is responsible for penicillin optimisations?
Repeated classical mutagenesis and screening
Is the spontaneous mutation frequency high or low?
10^-8
(Very Low)
What increases the rate of occurrence of mutations?
Random mutagenesis by interfering with DNA synthesis and DNA repair mechanisms
