MICROB C1

DYA20053 MICROBIAL TECHNOLOGY

  • Credit Hours: 3

  • Lecture Hours per Week: 2

  • Practical Hours per Week: 2

Course Overview

Topic List

  1. Introduction to Microorganisms

  2. Microorganisms in Agriculture

  3. Microorganisms in Industry, Environment & Waste Management

  4. Microorganisms in the Food Industry

  5. Microorganisms in the Feed Industry

TOPIC 1.0: INTRODUCTION TO MICROORGANISMS

Lesson Learning Outcomes

  • Explain the development of microbiology.

  • Differentiate between types of cells.

  • Identify types of microorganisms.

Terminology

Key Definitions

  • Microbe: Derived from the Greek words 'micro' (small) and 'bios' (life).

  • Microbiology: The scientific study of microscopic organisms, which include unicellular organisms and acellular organisms.

  • Microorganism: Any organism too small to be seen by the naked eye; includes bacteria, archaea, viruses, and certain fungi.

Microbial World

Types of Organisms

  • Living Infectious Agents:

    • Domain: Bacteria, Archaea, Eukarya

  • Non-Living Infectious Agents:

    • Viruses, Viroids, Prions

Categories of Microorganisms

  • Prokaryotes: Bacteria and Archaea

  • Eukaryotes: Algae, Protozoa, Fungi, and Helminths

HISTORY AND DEVELOPMENT

Milestones in Microbiology

  • 1796: First vaccine (smallpox) by Edward Jenner

  • 1857: Germ Theory of Disease by Louis Pasteur

  • 1867: Antiseptic Surgery by Joseph Lister

  • 1885: Vaccine against rabies developed

  • 1953: Structure of DNA revealed by Watson & Crick

  • 1954: Polio Vaccine by Jonas Salk

CLASSIFICATION OF MICROBES

Microbial Groups

  1. Bacteria

  2. Fungi

  3. Algae

  4. Protozoa

  5. Virus

BACTERIA

Overview

  • Bacteria are ubiquitous and exist in various ecosystems; necessary for breaking down organic materials and environmental processes.

Structure of Bacteria

  • Components:

    • Cell wall, Plasmid, Flagellum, Cytoplasm, Chromosomal DNA

Types of Bacteria

  • Archaebacteria: Thrive in extreme environments (salt brines, hot springs)

  • Eubacteria: Common forms, present in soil and on organisms; further classified into Gram-positive and Gram-negative.

Characteristics of Bacteria

  • Morphology: Prokaryotic, unicellular, and may be motile or non-motile.

  • Nutrition Types:

    1. Photosynthetic autotrophs: Utilize light for energy.

    2. Chemosynthetic autotrophs: Synthesize organic molecules from inorganic sources.

    3. Heterotrophs: Require organic compounds for nutrition.

Basic Forms

  • Cocci: Spherical shapes

  • Bacilli: Rod shapes

  • Spirilla: Spiral shapes

Gram Staining

  • Classification:

    • Gram Negative Bacteria (GNB): Red or pink, thin peptidoglycan layer, outer membrane present.

    • Gram Positive Bacteria (GPB): Purple, thick peptidoglycan layer, no outer membrane.

FUNGI

Overview

  • Fungi can be single-celled or multicellular, primarily terrestrial.

Ecological Role

  • Decomposers in the ecosystem, affecting nutrient cycling.

  • Some are plant pathogens causing diseases.

Structure of Fungi

  • Composed of hyphae, forming a mycelium; reproduction can be sexual or asexual.

Classification

  • Types:

    1. Multicellular filamentous molds

    2. Macroscopic fungi (mushrooms)

    3. Unicellular fungi (yeasts)

ALGAE

Overview

  • Aquatic, eukaryotic organisms lacking true roots, stems, and leaves; photosynthetic abilities due to chlorophyll.

Structure

  • Key features: Blade, Gas Bladder, Frond, Stipe, and Holdfast.

Types

  • Categories:

    1. Green algae

    2. Red algae

    3. Brown algae

    4. Blue-green algae (cyanobacteria)

PROTOZOA

Overview

  • Unicellular eukaryotic organisms, often classified as "first animals"; primarily heterotrophic.

Structure

  • Include cilia, macronucleus, micronucleus, and vacuoles for feeding and movement.

Movement Mechanisms

  1. Cilia: Hair-like structures for propulsion.

  2. Flagella: Long structures creating movement through whip-like action.

  3. Amoeboid Movement: Using pseudopodia for locomotion.

VIRUSES

Overview

  • Considered acellular entities and obligate intracellular parasites; unable to produce energy independently.

Structure

  • Composed of nucleic acid (RNA or DNA) within a protein coat (capsid).

  • Lack cellular structure, organelles, and metabolic functions.