The document discusses bacteria and provides information on several topics related to bacteria. It defines bacteriology as the branch of biology studying bacteria. It describes bacteria as single-celled microorganisms that are smaller than eukaryotic cells and lack organelles. Bacteria are classified based on their shape, cell wall composition, presence of flagella, nutrition sources, and temperature requirements. The document also discusses the structure of bacterial cells and various methods of bacterial reproduction.

1. Bacteria

2. Introduction
ALI ZAHID
OD02181008

3. Bacteriology
• Bacteriology is the branch and specialty of biology that
studies the morphology, ecology, genetics and biochemistry
of bacteria as well as many other aspects related to them.

4. Bacteria
• A prokaryotic and single cell microorganism.
• Small in size.
• Don’t have nuclear membranes and also lack membrane
bound organelles.
• Can be able to see by using Microscope.

6. • Bacteria are found in every habitat on earth, like growing
in soil, acidic hot springs and deep earth crust.
• Bacterial cells are 10 times smaller than the eukaryotic
cells and are typically 0.5 to 5.0 micrometers in length.
• There are 40 million bacterial cells in one gram of soil
and million in one milliliter of water.

7. History
In 1683 “Anton van Leeuwenhoek”
describes microscopic “ STREAKS
and THREADS” among his tiny
animals. The Streaks and Thread
remained nameless until 1773.

8. In 1773 Danish scientist named Otto
Frederick Muller named them as
“Bacilli”. But not Bacilli were rod
some were spiral and some were in
Circular shapes.

9. •In 1850 the French Investigator
Casimir Davaine began calling this
microscopic Creatures as Bacteria.
•This derivatives also mean rods.

10. Structure of Bacteria
Capsule:
• Protective covering.
• Made of polysaccharides.
• Protect it from phagocytosis by larger Micro-organisms.
Cell Envelope:
The cell envelope is made up of two to three layers: the interior
cytoplasmic membrane, the cell wall, and in some species of
bacteria an outer capsule.

11. Cell Wall:
• Composed of polysaccharides.
• Gives the cell its shape and surrounds the cytoplasmic
membrane.
• Protection
Cytoplasm:
• Helps in the cell growth, metabolism, and also in
replication.

13. Cytoplasmic Membrane:
• Layer of phospholipids and proteins.
• Regulate the flow of materials in and out of the cells.
Flagella:
• Hair-like structure.
• Provide means of locomotion.
• The flagella beat in a propeller-like motion to help the
bacterium move toward nutrients; away from toxic
chemicals.

14. Nucleoid:
• Region where the chromosomal DNA is located.
• It is not a membrane bound nucleus.
• Most bacteria have a single, circular chromosome that is
responsible for replication, although a few species do have
two or more.
Pili:
• Many species of bacteria have pili (singular, pilus)
small hair like projections emerging from the outside cell
surface.
• These outgrowths assist the bacteria in attaching to other cells
and surfaces, such as teeth, intestines.

15. Classification of Bacteria
Bacteria can be classified on the following basis:
• Basis of shapes
• Cell wall
• Flagella
• Nutrition
• Temperature response

16. On the basis of
SHAPES
QAYOUM HUSNAIN
OD 02181059

17. Classification
Bacteria are classified into 4 types on the basis of shapes:
• Coccus
• Bacillus
• Vibrio
• Spirilla

18. Coccus
• A coccus ( cooci ) is any bacterium or archaeon that has a
spherical,ovoid,or generally round shape.
Arrangements:
 Diplococci are pairs of cocci. (e.g. streptococcus
pneumoniae)

19. Staphylococci are irregular (grape-like) clusters of
cocci(e.g. Staphylococcus aureus)
Tetrads are clusters of four cocci arranged within the
same plain(e.g. Micrococcus sp.)
Sarcina is a genus of bacteria that are found in cuboidal
arrangements of Eight cocci. (e.g.Sarcina ventriculi.)
Streptococci are chains of cocci (e.g. streptococcus
pyogenes)

21. Bacillus:
• Bacillus is a genus of Gram positive rod shaped bacteria.
• Bacillus species can be either Obligate aerobe or Facultative
anerobe bacilli.
• OBLIGATE AREOBE:
Depend on Oxygen.
• FACULTATIVE ANEROBE:
Have ability to grow in the absence of Oxygen.

23. Vibrio
• Vibrio is a genus of Gram negative bacteria possessing a
curved rod shaped comma shape.
• Vibrio are found in salt water.
• All members are motile and have
flagella.

24. Spirilla
• Spiral bacteria are the helical shape bacteria
• They have two types
• Spirrilum (e.g. Campylobacter jejuni)
• Spirochete (e.g. Treponema pallidum)

25. On the basis of Cell
Wall
RABIA SAIFULLAH
OD02181030

26. GRAM POSITIVE
• Gram positive and negative are classified on the abililty to retain
the gram stain.
• The gram positive bacteria would retain the gram stain and
observe as violet colour after the application of iodine and alcohol.
• Cell wall consist of many layers of PEPTIDOGLYCANS which
forms a thick and rigid structure.It also contain “Techoic Acid”
which is made up of alcohola and phosphate.
Two types of techoic acis are formed:
• Lipotechoic Acid: Which spam the peptidoglycan layer linked to
plasma membrane.
• Techoic Wall Acid:Which is connected to peptidoglycan layer.

27. GRAM NEGATIVE
• The gram negative bacteria would be stained by the counter
stain safranin, as they are destined due to alcohol wash so they
appear as pink coloue under microscope.
• Cell wall is made up of few layers of peptidoglycans and an
outer membrane.
• The outer layer is made up of Lipopolyssacchrides,
Lipoproteins and Phospholipids.
• The peptidoglycans remain bound to the lipoproteins of the
membrane.It is present in periplasm, which is jel like fluid
between the outer and plasma membrane.

28. • Due to presence of lipoproteins in the outer membrane, cell
is not easily affected by antibodies, enzymes and metals.
• The outer membrane is permeable due to presence of
“PORIONS’ and is permeable to food, nutrition, water,
vitamin B12 and Iron.

31. On the basis of Nutrition

32. Autotrophic Bacteria
• Food is syntesised from
simple inorganic raw material
CO2 and H2O.
• Green pigment is necessary.
• Food is prepared during
daytime.
• EX: All GREEN plants and
some bacteria
Hetrotrophic Bacteria
• Food is obtained directly or
indirectly from autotrophs.
• No pigment is necessary for
nutrition.
• Food can be prepared at all
the time.
• Ex: All animals and Fungi.

35. On the basis of Flagella
Bacteria are classified on the basis of flagella:
• A-trichous
• Mono-trichous
• Amphitrichous
• Lophotrichus
• Peritrichous
• Cephalotrichous

37. Reproduction Of
Bacteria
ASAD HUSNAIN
OD 02181055

38. Method of reproduction
• Sexual reproduction
• Asexual reproduction
Asexual reproduction
In asexual reproduction single organism produce genetically
identical offspring.
Types:
1. Endospore formation
2. Vegetative reproduction

39. Endospore formation
• Resting spores found in gram positive bacteria.
• During formation protoplasm constricted around
the chromosomes and a hard resistant wall
secreted around it.
• Rest of the bacterial cell degenerate.

41. Vegetative reproduction
Binary fission
Budding
Fermentation

43. Budding
• Small protuberance bud, develops at one end of bacteria.
• Genome replication occurs, and one copy of genome gets into
the bud.
• Bud enlarges and eventually separate from the parent cell.

44. Fragmentation
• During unfavorable condition, bacterial protoplasm
undergoes compartmentization forming minute
bodies called Gonidia.
• During favorable condition each Gonidia Grows to new
bacterium.

45. Sexual reproduction
• In sexual reproduction, two parents are involved and offspring
are not genetically identical.
Types:
1. Conjugation
2. Transformation
3. Transduction

46. Conjugation
• In conjugation one bacterial cell transfer genetic material into
other bacterial cell.
• Its is transferred in form of plasmid known as “F-plasmid.”
• A cell that has a copy of F-plasmid is known as F positive
and this cell is donor.
• The cell that does not have copy of F-plasmid is known as F-
negative and it is recipient cell.

47. Steps of conjugation
 F- positive cell produce pilus.
 The pilus enables the direct contact between the donor and
the recipient cells.
 An enzyme relaxasome transferasome nick one of the two
DNA stands of F-plasmid and this strand is transferred to
recipient cell.
 Both donor and recipient cell to contain single stranded DNA.
Replication of this DNA occur forming double stranded
F-plasmid identical two original F-plasmid.

49. Transformation
• In transformation a bacteria takes in DNA from its environment
often DNA that has been shed by another bacteria. If DNA is a
circular DNA called a plasmid, It can be copied in receiving
cell.

50. Transduction
• In transduction viruses that infect the bacteria
(BACTERIOPHAGE) move short pieces of
chromosomal DNA from one bacterium to an other by
accident.

52. Bacterial Infection
MARIA SAEED
OD02181098

53. Baterial infection
• It an invasion of body tissues by disease causing Bacteria or the
poliferation of harmful stains of bacteria that can effect any part
of body.
It can be caused by contact with :
• Infected people.
• Coughing and sneezing.
• With infected creatures.
• With contaminated surfaces.

54. Carbuncle
• Carbuncle is the skin infection resulting in th formation of
LUMP that may contain pus.
• It is also known as “STAPH SKIN INFECTION”.
• Caused by group of contegious follicles with “Staphylococcus
Aureus”.
 CLINICAL FETURES:
• Fever
• Fatigue
• Irritation
• Pain around infected area
• Itching

55. Tularemia
• It is also called “RABBIT FEVER”.
• It is caused by the bacterium Francisella tularensis
that can effect your SKIN, LUNGS, EYES and LYMPH
NODES.
 CLINICAL FEATURES:
• Uleroglandular (most common)
• Oculoglandular
• Orophyrangeal

56. Impetigo
• It is caused by Staphlococcus aureus and A. Streptococcus.
• Mostly occur in infants and children.
• Lead to complications like cellulitus ,kidney problems and
scarring.
 CLINICAL FEATURES:
• Ictching
• Swollen lymph nodes
• Open sores with yellow crust
• Painful blisters

57.  Bollus:
• “Staphalococcus Aureus”
• Vesicles rupture easily.
• Honey coloured crusted
plague.
 Non-Bollus:
• “S.Aureus,
A.streptococcus”.
• Less rupture and become
large.
• Persist 2-3 days.

58. Leprosy
• An infectious disease also known as “Henson’s Disease”,
caused by MYCOBACTERIUM LEPRAE.
 CLINICAL FEATURES:
• Damages to SKIN and PERIPHERIAL NERVES.
• May involve other organs like
Testes, bones and muscles, eyes,
upper respiratory tract.

59. Cancrum oris
• Also known as “GANGREONUS STOMATITIS” (NOMA).
• Caused by oral contamination of by heavy infestation of
“FUSOBACTERIUM NECROPHORUM”.
 CLINICAL FEATURES:
• Suffer from dibalitating diseases.
• Spread rapidly and become necrotic.
• Gingival Ulcer

60. Gonorrhoea
• An infection caused by sexually trasnmitted bacteria that often
affects the urethra, rectum or throat.
• It is caused by “Neisseria gonorrhoeae”.
 CLINICAL FEATURES:
• Painful urination.
• Swelling in testicles.
 COMPLICATIONS:
• Infertility in males and females.
• High risk of HIV.
• Complications in babies.