The document discusses three types of microbes commonly used in biotechnology - bacteria, viruses, and fungi. It provides examples of specific microbes from each type, including bacteria like Lactobacillus and Escherichia coli, viruses like influenza virus and rabies virus, and fungi such as Candida and Aspergillus. It also describes characteristics of each microbe type and how they reproduce.

1. Commonly Used
Microbes in
Biotechnology

2. Microbes
•Microbes are tiny living things that are
found all around us and are too small to be
seen by the naked eye. They live in water,
soil, and in the air. The human body is home
to millions of these microbes too, also called
microorganisms.

3. Three Different Types of Microbes
•Bacteria
•Virus
•Fungi

4. Bacteria
• Bacteria are one-celled organisms. They can be found almost
everywhere. They come in three basic shapes- rods, spheres,
and spirals. Some have tails called flagella that enable them to
move.

5. • Bacteria are classified according to shape. Also
notice that cocci (sing. coccus), are differently
arranged. They can form pairs (diplococcus),
chains (streptococcus), or clusters
(staphylococcus). Bacilli can also occur in chains
(streptobacillus).

6. • Some bacteria have a sticky gelatinous capsule around their
cell wall. The cell wall that contains peptidoglycan protects the
bacterium by preventing it from bursting.
• They also have genes located in a single circular chromosome
and not enclosed in a nucleus. A few genes are in a small
circular chromosome piece called a plasmid.
• Some have pilli, a hairlike structure emerging from the cell
surface which helps the bacterium stick to a surface and
bridges the exchange of DNA between two bacteria. And a
plasma membrane that surrounds the cell and regulates what
enters and leaves the cell.

7. • Lactobacillus is generally one of the good bacteria. For
instance, it is friendly to our gut. It is also noted for its effect on
milk products, producing buttermilk, yogurt, sour cream, and
cheese.
• Escherichia coli is the most common bacteria in our intestine.
They help our body breakdown the food we eat and assist in the
production of vitamins that our body cannot reproduce by itself.
But they may also cause human infections. (Cyanocobalamine
or Vit. B12)
• Pseudomonas may cause diseases to us, but some are
important in decomposition and bioremediation.
• Streptomyces, a filamentous and soil-dwelling bacterium is
used in the production of antibiotics such as streptomycin and
chloramphenicol

8. Virus
• Viruses are the smallest type of microbes, even smaller than
bacteria. They come in many shapes. Many have geometric shapes,
like cut diamonds, others are liked spiky eggs, and some are more
complicated, like a tiny spaceship landing pods.
• They are considered nonliving because they don’t exhibit all the
criteria for life except reproduction.
• Viruses reproduce only when they are inside a living cell. Once
inside the host cell, they rapidly multiply destroying the cell in the
process.

9. • A typical virus has an inner core of nucleic acid,
either RNA or DNA, which contains instructions
for making copies of the virus. And an outer
protein coat called a capsid. The capsid includes
a protein that enables a virus to enter a host cell.

10. • Some viruses were named after the disease they caused.
Rabies virus is a neurotrophic virus that causes rabies in
humans and animals.
• Influenza virus is a contagious respiratory illness that infects the
nose, throat, and sometimes lungs.
• Most viruses are highly specific to the cells they infect. Bacterial
viruses infect only a certain type of bacteria.
• Bacteriophage virus is a virus that infects a bacterium. It is now
used as antibacterial agents. It is also used as DNA delivery
vehicles, moving genes from one bacterium to another resulting
in bacterial adaptive evolution

11. Fungi
 Fungi are eukaryotic nonmotile organisms that obtain food by
decomposing organic matter.
 Most species are multicellular, but there are some which are
unicellular, such as yeast.
 Fungi come in a variety of shapes and sizes and different types.
They can range from single cells to enormous chains of cells that
can stretch for miles.
 Most fungi reproduce asexually by forming spores while some like
yeast is through budding. And there are some which reproduce
sexually when the two mating strains come in contact.

12. • The cell walls of most fungi contain a hard
substance called chitin. The basic structural units
of multicellular fungi are their threadlike filaments
called hyphae which develop from fungal spores.
• It contains cytoplasm and one or more nuclei.

13. • Fungi can be harmful by causing infection or being poisonous to
eat. Others can be beneficial or harmless.
• Candida, a yeast, grows in moist regions of the body, may
cause a painful infection.
• Agaricus can be eaten (button mushroom).
• Aspergillus may cause diseases but also useful in the
production of citric acid and extracellular enzymes.
• Penicillium may also harm us once inhaled or ingested. But
some members may be used as antibiotics which can inhibit the
growth of a certain bacteria.
• Saccharomyces, which means “sugar fungi”, is the most
common yeast used for baking and brewing

14. 1. Saccharomyces
2. Penicillium
3. Aspergillus
4. Agaricus
5. Candida
6. Bacteriophage
7. Influenza virus
8. Rabies virus
9. Streptomyces
10.Pseudomonas
11.Escherichia coli
12.Cyanocobalamine
13.Lactobacillus
14.Cocci
15.Bacilli
16.Spirilla
17.Bacteria
18.Virus
19.Fungi
20.Bonus