Module 2

Fermentation and Industrial Microbiology

1. Vinegar – Produced by Acetobacter aceti.
2. Curd/Yogurt – Produced by Lactobacillus bulgaricus.
3. Butyric acid – Produced by Clostridium butyricum.
4. Lactic acid – Produced by Lactobacillus delbrueckii.
5. Ethanol fermentation – By Saccharomyces cerevisiae.
6. Citric acid – Produced by Aspergillus niger.
7. Acetone-butanol fermentation – Clostridium acetobutylicum.
8. Single Cell Protein (SCP) – Spirulina, Chlorella, Candida utilis.
9. Bio-pesticides – Bacillus thuringiensis (Bt) used against caterpillars.
10. Bt toxin gene – Cry gene (Cry1Ac, Cry2Ab).

Biotechnology and Microbial Tools

1. First recombinant DNA molecule – By Stanley Cohen and Herbert Boyer (1973).
2. Agrobacterium tumefaciens – Natural genetic engineer of plants.
3. Ti plasmid – Used for gene transfer in plants.
4. Binary vector system – Used for plant transformation.
5. PCR (Polymerase Chain Reaction) – Developed by Kary Mullis (1985).
6. Restriction enzymes – Discovered by Smith and Nathans (1970).
7. Bt cotton – First GM crop in India (approved 2002).
8. Golden rice – Rich in β-carotene (Vitamin A precursor).
9. Cry genes – Source of insect resistance.
10. Plasmid – Circular extra-chromosomal DNA in bacteria.

Miscellaneous Important Facts

1. Microbial inoculants should be stored at 4°C.
2. Carrier material in biofertilizer – Peat, lignite, vermiculite.
3. Shelf life of biofertilizer – Around 6 months.
4. Bacteriophage – Virus that infects bacteria.
5. Archaebacteria – Found in extreme environments (hot springs, saline water).
6. Thermophiles – Grow at high temperature (60°C or above).
7. Psychrophiles – Grow at low temperature (below 20°C).
8. Mesophiles – Grow at moderate temperature (25–40°C).
9. Halophiles – Salt-loving microbes.
10. Acidophiles – Grow in acidic environment.
11. Obligate aerobes – Require oxygen (e.g., Nitrosomonas).
12. Obligate anaerobes – Grow without oxygen (e.g., Clostridium).
13. Facultative anaerobes – Can grow with or without oxygen.
14. Autotrophs – Prepare their own food.
15. Heterotrophs – Depend on organic matter for food.
16. Chemolithotrophs – Use inorganic compounds as energy source.
17. Photoautotrophs – Use light energy for synthesis (e.g., cyanobacteria).
18. Saprophytes – Live on dead organic matter.
19. Parasites – Live on living hosts.
20. Pathogens – Cause disease in hosts.

Microbial Genetics and Molecular Biology

1. DNA was discovered by Friedrich Miescher (1869).
2. Double helix model of DNA was proposed by Watson and Crick (1953).
3. RNA contains ribose sugar, while DNA contains deoxyribose sugar.
4. DNA replication is semi-conservative (proved by Meselson & Stahl, 1958).
5. Transcription – Formation of RNA from DNA template.
6. Translation – Formation of protein from mRNA.
7. Codon – A sequence of three bases coding for one amino acid.
8. Start codon – AUG (Methionine).
9. Stop codons – UAA, UAG, UGA.
10. Mutation – Sudden heritable change in DNA sequence.
11. Mutagenic agents – UV rays, X-rays, ethidium bromide.
12. Plasmids – Extrachromosomal circular DNA in bacteria.
13. Conjugation – Gene transfer via pili (cell-to-cell contact).
14. Transformation – Uptake of free DNA from surroundings.
15. Transduction – Gene transfer by bacteriophage.
16. Operon model – Proposed by Jacob and Monod (1961) in E. coli.
17. Lac operon – Regulates lactose metabolism in E. coli.
18. Restriction enzymes – Discovered in 1970 by Smith and Nathans.
19. Ligase enzyme – Joins DNA fragments.
20. Reverse transcriptase – Synthesizes DNA from RNA template (found in retroviruses).

Biofertilizer Production and Formulation

1. Carrier materials – Peat, lignite, charcoal, vermiculite, FYM, coir pith.
2. Ideal moisture content of carrier – 40 %.
3. pH for biofertilizer growth – Around 7.0 (neutral).
4. Viable cell count – Minimum 10⁸ viable cells / g required.
5. Shelf life – 6 months (carrier-based), up to 12 months (liquid biofertilizers).
6. Liquid biofertilizers are more stable and tolerant to temperature.
7. Rhizobium inoculant is crop-specific (e.g., Rhizobium japonicum for soybean).
8. PSB inoculant improves P availability through solubilization.
9. VAM inoculant is produced on live host roots (e.g., maize, sorghum).
10. Azospirillum inoculant improves root growth via auxin production.
11. Azotobacter secretes vitamins B and IAA improving germination.
12. Storage temperature – 15–25 °C for longer viability.
13. Application methods – Seed treatment, seedling dip, soil application.
14. Rhizobium inoculation dose – 200 g / acre for seed treatment.
15. Mixing biofertilizers with chemical fertilizers should be avoided directly.
16. PSB converts insoluble tricalcium phosphate into soluble monocalcium phosphate.
17. KSB (Potassium Solubilizing Bacteria) releases K from mica and feldspar.
18. ZSB (Zinc Solubilizing Bacteria) converts ZnO/ZnCO₃ to available Zn²⁺.
19. Co-inoculation of Rhizobium + PSB + KSB enhances overall nutrient efficiency.