1

BACTERIA

Introduction

Classification of bacteria

Industrial importance of bacteria

2

Structure of bacteria

3

Classification of bacteria

1. Shape

2. Arrangement

3. Ability to accept gram stain

4. Habitat

5. Metabolism

6. O2 requirement

7. Beneficial/ harmful

Cont…

4

1. According to shape

5

Different colony morphology of bacteria

6

7

2. According to arrangement

8

9

3. According to gram staining

10

11

4. According to the habitat

1. Thermophiles: 45 and 122 °C

Thermophilus aquaticus

2. Extreme thermophiles

3. Psychrophiles: -15 -100C

4. Psychrotrophs

5. Mesophiles - 20 - 450C

6. Hallophiles - High salt - Methanogens

Temperature requirement

12

5. According to the metabolism

13

Autotrophic photosynthetic

Cyanobacteria (Blue-green algae) - Nostoc and Anaebena

Heterotrophic

Curdling milk

Production of antibiotics

Nitrogen fixation

Pathogens

Write examples!

14

6. According to the O2 requirement

15

Based on number of flagella

16

Industrial Application of bacteria

1. Nitrogen fixation

2. Bioremediation (Effective micro organisms)

3. Biological control

4. Growth promotion of plants

5. Usage in Genetic engineering and Biotechnology

6. Vaccine production

7. Antibiotic production

8. Fermentation

9. Usage in Dairy industry

10.Usage in Feed formulation industry

11.Usage in Fiber industry

12.Usage against environmental pollution

Cont….

17

Azotobacter colonies

Nitrogen fixation

18

Rhizobia in Soy bean

Nitrogen fixation

19

Colony of Rhizobium

Nitrogen fixation

20

Lactococcus lactis

Usage in Dairy industry

21

Agrobacterium tumefaciens

Usage in Genetic engineering and

Biotechnology

22

23

Probiotic bacteria

Usage in Dairy industry

24

Nitrosomonas

Nitrogen fixation

25

Burkholderia spinosa

Colletotrichum musae (Cigar end rot)

Biological control

26

27

Pseudomonas fluorescens

28

Bacterial insecticides

• Bacillus thuringiensis

• Bacillus sphericus

• Bacillus lentimobus • Bacillus popillae

29

Cry Protein

Midgut pHProtoxins

Proteolytic processingProteolytic processing

Active toxins

Mode of action of Bacillus thuringiensis

30

Bacillus thuringiensis

31

Tobacco curing

Crude dry tobacco leaves pass through curing and ripening processes before they are ready for use

Bacteria are employed in both these processes and the peculiar taste and smell in the tobacco is due to the bacterial activity

For this purpose molasses and alcohol are added to tobacco.

32

Ammonifying bacteria

Bacillus subtilisBacillus mycoidesBacillus ramosus

Act upon the dead animal and plant tissues

Decompose their complex organic compounds like proteins into ammonium compounds (Humus)

They are also known as putrefying bacteria

33

Found in the soil

Fixes the nitrogen gas of the atmosphere in the presence of carbohydrates

This fixation of free nitrogen from the atmosphere through ammonia into free nitrates and again their conversion into ammonia and free nitrogen takes place by means of nitrifying and denitrifying bacteria, along with other organisms

Azotobacter

34

Vinegar making industry

Bacillus aceti convert the sugar solution into

vinegarAlcohol and acetone manufactureButyl alcohol and acetone are manufactured by the action of bacteria on molasses

35

Tea curingCrude tea leaves are acted upon by certain bacteria. The process is known as curing, which is employed to impart a peculiar taste and flavour to the leaves. For this purpose alcohol is added to tea leaves.

Leather tanningThe hides and skins after drying, salting and clearing are steeped in fluids containing specific bacteria. The process of fermentation goes on for some time and then they are transferred to tan-pits and are further allowed to be fermented. This whole process is known as tanning and the bacteria employed in the process are obtained from cowdung and the excreta of dogs and poultry.

36

Fibre rettingRetting is the process of separating fibres from-the plant tissues. Bacteria are employed in this industry, which cause decay of the softer tissues and render fibres easily separable mechanically. Fibres of flax, hemp, jute, coconut and other fibrous plants are obtained by immersing the specific plant organs in stagnant pond water where bacteria develop and cause retting.

The sewage workIn order to remove solid and semi-solid constituents of sewage it is allowed to putrify. Putrifying bacteria are allowed to act upon sewage under anaerobic conditions. It gets decayed and liquefied. It is now filtered and the liquid is either drained out to the river or used as manure in fields. For this purpose, in the soak pits the horse dung is filled up.

37

EnsilageIt is the process of preserving green fodder in pits. Certain bacteria help in the preservation of fodder.

MedicinesAntitoxins are the chemical substances produced in the host tissues in response to the attack of parasitic bacteria. Different vaccines and serums now prepared from these antitoxins are used in the treatment of specific ailments. The antibiotics such as streptomycin, aureomycin and chloromycetin are obtained from certain actinomycetous bacteria.

38

THE END!