Introduction to Microbiology

1. Introduction to Microbiology Dr Mohammad Altamimi

2. Important rules • Mobile phone off • Talk to me directly.

3. Micro- organism • Microbes • Microbial sciences • Pathogens

4. Bacteriology The bacteria—small single-celled prokaryotic organisms Mycology The fungi, a group of eukaryotes that includes both microscopic eukaryotes (molds and yeasts) and larger organisms (mushrooms, puffballs) Protozoology The protozoa—animal-like and mostly single-celled eukaryotes Virology Viruses—minute, noncellular particles that parasitize cells Parasitology Parasitism and parasitic organisms—traditionally including pathogenic protozoa, helminth worms, and certain insects Phycology or Algology Simple photosynthetic eukaryotes, the algae, ranging from single-celled forms to large seaweeds Morphology The detailed structure of microorganisms Physiology Microbial function (metabolism) at the cellular and molecular levels Taxonomy Classification, naming, and identification of microorganisms Microbial Genetics, Molecular Biology The function of genetic material and biochemical reactions that make up a cell’s metabolism Microbial Ecology Interrelationships between microbes and the environment; the roles of microorganisms in the nutrient cycles and natural ecosystems • What, where, why.

5. How small is small?

6. Importance of microorganisms

8. History

10. How do we know?

11. How can you study microbiology? • Specific tools

12. Modern tools

13. Is it easy to study microorganisms? Because microbiologists cannot rely as much as other scientists on senses other than sight, they are confronted by some unique problems. First, most habitats (such as the soil and the human mouth) harbor microbes in complex associations. It is often necessary to separate the organisms from one another so they can be identified and studied. Second, to maintain and keep track of such small research subjects, microbiologists usually will need to grow them under artificial conditions. A third difficulty in working with microbes is that they are not visible to the naked eye. How can you identify microorganism?

14. To overcome challenges • Microbiologists have developed several types of procedures for investigating and characterizing microorganisms. • These techniques can be summed up succinctly as the six “I’s”: inoculation, incubation, isolation, inspection, information gathering, and identification

16. Six “I”s

18. Isolating technique

19. Media classification

20. Enriched medium contains complex organic substances such as blood, serum, hemoglobin, or special growth factors that certain species must be provided in order to grow. Blood agar Selective medium contains one or more agents that inhibit the growth of a certain microbe or microbes MacConkey agar Differential media grow several types of microorganisms but are designed to bring out visible differences among those microorganisms. MacConkey agar +neutral red(dye)

22. LightMicroscopy Adequate resolution and Clear magnification.

23. The cell theory The basic unit of all living things is the cell. The fundamental cell theory is one of concepts of biology; it states that: - all organisms are made up of cells, and that -all cells come from other, pre-existing cells. unicellular multicellular different Colonial same examples

24. Tow types of cells • Procaryotic Bacteria and blue-green algae • Eucaryotic true cell with nucleus Fungi (mold, yeasts),protozoa, algae

26. Classification of Microorganisms Microorganisms With nucleus Without nucleus Molds yeasts protozoa Eubacteria (bacteria) Archaea Gram stain Protein profile Base composition C+G % (10%) DNA RNA hybridization (90%) Nucleotide sequence. Morphology Reproduction Metabolic patterns viruses

27. Bacteria

28. Bacterial cell wall

29. Gram+ vs Gram -

31. MycoplasmasCell-Wall-Deficient Bacteria Mycoplasmas are bacteria that naturally lack a cell wall. Although other bacteria require an intact cell wall to prevent the bursting of the cell, the mycoplasma cell membrane contains sterols that make it resistant to lysis. These extremely tiny bacteria range from 0.1 to 0.5 μm in size.

32. Functions of the Cell Membrane • provides a site for energy reactions, nutrient processing, and synthesis. • Regulate transport, that is, the passage of nutrients into the cell and the discharge of wastes. • involved in secretion, or the release of a metabolic product into the extracellular environment. • important site for a number of metabolic activities. For example, most enzymes that handle the energy reactions are on C M.

33. Cell content (70-80% water) • Bacterial Chromosomes and Plasmids: Chromosomes (linear DNA), plasmid’s non essential chromosome. Involved in drug or enzyme resistance, genetic engineering. • Ribosomes: Sites of Protein Synthesis: Involved in protein synthesis. Chemically, a ribosome is a combination of a special type of RNA called ribosomal RNA, or rRNA(about 60%), and protein (40%)

35. Protein synthesis Many antibiotics like streptomycin and tetracycline who inhibit the protein synthesis in bacterial cell have a main target on the ribosome of the bacterium.

36. Granules: Storage Bodies • Spores Some bacteria are spore forming bacteria. What induce sporulation?: Under unfavorable condition when there is no cellular division and there is scarcity of ATP or energy in the cell, a special gene become active and is found responsible for the formation of endospore. • Lack of nutrients • Harsh environment. • Anti microbial agents.

38. Shapes of bacteria

39. Homework • 1. What is required to kill endospores? How do you suppose archaeologists were able to date some spores as being thousands(or millions) of years old?

40. Cell division in prokaryotes • binary fission leads to the creation of a new individual. single binary fission is completed within 18-20 minutes.

42. limitation for growth 1. Lack of space, food, water, oxygen other salts and accumulation of their own harmful waste products in the medium. 2. Environmental factors like light, temperature, moisture becomes unfavorable. 3. Death due to senescence and sometimes they are eaten by microscopic animals and viruses. Therefore survival rate of bacteria in nature is only 1 %.

43. NUTRITION Two types: (1) Autotrophic A very small group of bacteria possess this type of nutrition. Few bacteria possess photosynthetic pigment bacteriochlorophyll other than normal chlorophyll found in higher plants are called photosynthetic bacteria. Thus autotrophic bacteria are of two types: (i) Photosynthetic bacteria (ii) Chemosynthetic bacteria

44. (2) HETEROTROPHIC BACTERIA utilize nutrition from other living being. Though they lack the photosynthetic pigment they are unable to utilize solar energy. Such as: (a) Saprophytic (b) Symbiotic (c) Parasitic bacteria. Dead bodies Commensal and beneficial Live on host/harmful

45. Viruses Swin flu first diagnoses in March 2009, the influenza outbreak exploded into a pandemic in only six weeks.” • By mid-April 2009, nearly 1,000 Mexican cases had been reported, with around 70 deaths. • How do the receptor spikes on viruses play a role in infection? • How is it possible for the same influenza virus to be able to infect both swine and humans?

46. There is no universal agreement on how and when viruses originated. • In terms of numbers, viruses are considered the most abundant microbes on earth. • Many of them are parasites of bacteria • viruses are unable to exist independently from the host cell, so they are not living things. • Ultramicroscopic size, ranging from 20 nm up to 450 nm (diameter) • Nucleic acid can be either DNA or RNA but not both. • Lack enzymes for most metabolic processes. • Lack machinery for synthesizing proteins.

47. Viral Components: Capsids, Nucleic Acids, and Envelopes capsid Nucleic acid Envelop Spikes

49. Classification of viruses