Lecture 1 - Introduction PDF

Introduction LECTURE 1 Introduction Common properties of microorganisms (bacteria, fungi parasites and viruses) 2022  What is Microbiology? Introduction...

Introduction LECTURE 1 Introduction Common properties of microorganisms (bacteria, fungi parasites and viruses) 2022  What is Microbiology? Introduction Micro: Too small to be seen with the naked eye Bio: Life Logy: Study of Microbiology: The science that studies very small living things Usually requires a magnification tool – a microscope  What does the term microorganism mean? Introduction Microorganism (Microbes) are tiny living things that are found all around us and are too small to be seen by the naked eye. Live in water, soil, and in the air. (in us, on us and all around us) The human body is home to millions of these microbes too Some organisms are large though – Helminths – worms  History: Introduction The First Description of Microorganisms Robert Hooke observed fruiting structures of molds in 1665 and was the first to describe microorganisms  History: Introduction Adjustment Lens  History: Introduction The First Description of Bacteria Antoni van Leeuwenhoek was the first to describe bacteria in 1676 Scan QR code for more information  History: Introduction Van Leeuwenhoek’s Microscope Van Leeuwenhoek’s Microscope Portrait of Van Leeuwenhoek looking into his microscope  History: Introduction Van Leeuwenhoek’s drawings of various organisms  History: Introduction Louis Pasteur Robert Koch Best known for his discoveries of the Best known for his description of germ principles of microbial fermentation, theory of disease and description of and pasteurization tuberculosis, cholera and anthrax  Discovery of Penicillin Introduction “One sometimes finds what one is not looking for” Fleming Sir Alexander Fleming (1881 – 1955) Best known for discovering the world's first broadly effective antibiotic substance  Microbes we will be studied Introduction The field of microbiology was unable to develop without the work of those great minds  Microbes we will be studied Introduction Bacteria https://ecos.csiro.au/water-treatment/  Microbes we will be studied Introduction Fungi https://www.futura-sciences.com/sante/actualites/infection-premiere-fois-chercheurs-identifient-hybride-deux-champignons-pathogenes- 81778/  Microbes we will be studied Introduction Protozoa  Microbes we will be studied Introduction Virus  Microbes we will be studied Introduction Worms  Various disciplines of study within microbiology Introduction Bacteriology Mycology Virology Parasitology Epidemiology Biotechnology Environmental Microbiology  Microorganisms in Our Lives Introduction 1. Microorganisms are important in the maintenance of an ecological balance on Earth Microbial communities participates in making the essential elements of oxygen, carbon, nitrogen, and sulfur available for other life on our planet. They remove toxins from their environments. Without microbial decomposer communities, life would be smothered in dead organisms. Microorganisms also carry out almost half of the photosynthesis on our planet, increasing oxygen levels and lowering carbon dioxide. Video: Scan QR code for more information  Microorganisms in Our Lives Introduction 2. Microorganisms are important for humans, animals, and plants health and nutrition. Humans, animals and plants are closely associated with microbial communities that make nutrients more available, provide protection from diseases, make essential vitamins, or a combination. Each human body hosts 10 microorganisms for every human cell, and these microbes contribute to digestion, produce vitamin K, promote development of the immune system, and detoxify harmful chemicals.  Microbes are essential to making many foods we enjoy, such as bread, and cheese. Scan QR code for more information  Microorganisms in Our Lives Introduction 3. Microorganisms are new source of information and provide insights in many settings, diseases conditions, food safety, and supply chains Scan QR code for more Quigley, E. Gut microbiome as a clinical tool in gastrointestinal disease management: are we there yet?. Nat Rev Gastroenterol Hepatol 14, 315–320 (2017) information  Microorganisms in Our Lives Introduction 4. Microorganism can cause infectious diseases…. Neisseria meningitidis Smallpox virus Corona virus/COVID-19 HIV Plasmodium falciparum Vibrio cholerae Yersinia pestis Mycobacterium Ebola virus tuberculosis Introduction Classification and Binomial Nomenclature….. Not fun !!!!! No one likes it!!! We are Just going to do it!!!  The Classification of Living Things Introduction Living organisms are assigned to groups based upon their similarities Systematics (Taxonomy): is the discipline of identifying and classifying organisms.  Prokaryotic vs. Eukaryotic cells Introduction Prokaryotic cells Eukaryotic Cells – No Nucleus – Nucleus – No Organelles – Organelles – Cell Wall of – If cell wall, Cellulose peptidoglycan or chitin – Binary Fission – Mitosis – 1 circular – Linear chromosomes chromosome  Prokaryotic vs. Eukaryotic cell structure Introduction  Three Domains of life Introduction In the late 1970’s, primarily based on small subunit ribosomal RNA sequence comparisons pioneered by Carl Woese, the development of the three domains of life occur Carl Woese (1928-2012)  Domain Comparison Introduction BACTERIA ARCHEA EUKARYA Nuclear Absent Absent Present Envelope Membrane Absent Absent Present Organelles Peptidoglycan Present Absent Absent Cell Wall Ribosomes Present Present Present  Three Domains of life Introduction Archaea – ancient “bacteria”, unicellular like bacteria, also simple cell structure (prokaryote – no nucleus) but have distinct metabolism (chemistry) allowing them to exist in “extreme” environments Bacteria – unicellular, prokaryote, found everywhere (Old kingdom name – Monera) Eukarya – unicellular to multicellular, complex and organized cells with nuclei and organelles (mitochondria)  Archaeal Domain Introduction Archaea are single- celled organisms that lack a membrane-bound nucleus. - Prokaryote Archaea can be found in environments that are too hostile for other life forms. Yellowstone National Park Scan QR code for more information  Bacterial Domain Introduction Bacteria are single- celled organisms that lack a membrane-bound nucleus. (Prokaryote also) Bacteria are found almost everywhere on the planet Earth.  Eukaryotic Domain Introduction The cells of all eukaryotes have a membrane-bound nucleus Members of the Domain Eukarya are further categorized into one of four Kingdoms.  Eukaryotic Kingdoms Introduction  Categories of Classification Introduction Most inclusive Domain Kingdom Phylum Class Order Family Genus Species Least inclusive  An Example of Bacterial Taxonomic Classification Introduction Escherichia coli Kingdom Non assigned for bacteria Phylum Proteobacteria Class Gamma-Proteobacteria Order Enterobacteriales Family Enterobacteriaceae Genus Escherichia species coli  Classification of Bacteria Introduction Bacteria can be classified based on: 1. Phenotypic characteristics (Morphology) Shape, size and cell structure  Classification of Bacteria Introduction The standard diagnostic lab techniques to classify bacteria is Gram stain It divides bacteria into 3 groups or divisions based on their Cell Wall 1. Gram +ve (stain violet) 2. Gram -ve (destain, and are counterstained pink or reddish color) 3. Bacteria that lack a cell wall (mycoplasma) Gram-positive Gram-negative Hans Christian Gram  Classification of Bacteria Introduction 2. Metabolic characteristics: a) Classification of bacteria based on the Mode of Respiration - Obligate aerobe: - An organism that requires oxygen to grow - Obligate anaerobe: - Those bacteria that do not live or grow when oxygen is present - Facultative anaerobe: - Those bacteria that can grow in both the presence or absence of oxygen (optional) - Microaerophile: - Those bacteria which requires low levels of oxygen to survive - Aerotolerant anaerobes: - Those bacteria which tolerate oxygen but do not grow in it  Classification of Bacteria Introduction 2. Metabolic characteristics: b) Classification of bacteria based on the Mode of Nutrition - Phototrops: - Those bacteria which gain energy from light - Chemotrops: - Those bacteria gain energy from chemical compounds - Autotrops: - Those bacteria which uses carbon dioxide as sole source of carbon to prepare its own food - Heterotrops: - Those bacteria which uses organic compound as carbon source  Classification of Bacteria Introduction 3. More modern methods now used molecular techniques for classification:  DNA studies, genomics sequence, and 16rRNA -Serological and molecular techniques also have been applied to type bacterial species such as: Multi-sequence analysis of specific genes Using Bacterial viruses' “bacteriophages” Serology – antibody – antigen reactions (like blood typing) Examples: Salmonella typhi Salmonella typhimurium Azotobacter vinelandii 12837 E. coli 0157H7 (nasty strain of E. coli)  Scientific Names Introduction Binomial (two name): Genus first and first letter capitalized, then species not capitalized If it is written or typed – should be either underlined or italicized Bacterial examples First letter NOT capitalized First letter capitalized Genus name species name Type Escherichia coli italicized Escherichia coli Underlined Staphylococcus aureus italicized Staphylococcus aureus Underlined  Different types of Bacteria Introduction  Different types of viruses Introduction  Different types of fungi Introduction  Different types of Parasites Introduction  Comparison between Bacteria –Virus-Fungi-Protozoa Introduction