Unit 1- Foundation of Microbiology.pdf

Unit 1: Foundation of Microbiology Presented by: Ms Muhongo  Learning objectives By the end of this unit, the students should be able to : ❖Define Microbiology & why does it matters ❖Understand branches of microbiology and microbiology industries ❖Identify pioneers in...

Unit 1: Foundation of Microbiology Presented by: Ms Muhongo  Learning objectives By the end of this unit, the students should be able to : ❖Define Microbiology & why does it matters ❖Understand branches of microbiology and microbiology industries ❖Identify pioneers in the history of microbiology ❖State the contributions made by these pioneers in microbiology ❖Differentiate between the various microscopes. ❖Understand elements, atoms, molecules and compounds ❖Differentiate between types of chemical bonds ❖Know types of biological molecules ❖Understand essential of metabolisms  TERMINOLOGIES ❖Microbiology- The scientific study of microorganisms Is often considered an advanced branch of biology that explores both living and nonliving organisms. ❖Microbes/ microorganisms- They are microscopic organism or small organisms that are too small to be seen with naked eyes. E.g bacteria, viruses, protozoa (parasites) etc. ❖Microscope- Is an optical instrument -used to observe tiny objects. Pathogen- a microorganism that cause a diseases Non-pathogen- a microorganism that do not cause diseases  Microorganisms/ Microbes ✓Microbes are ubiquitous, meaning they are found everywhere in our environment. These very small organisms, typically microscopic and invisible to the naked eye, include bacteria, protozoa, fungi, and viruses. ✓Microorganisms are either: non-pathogens or pathogens.  Pathogens diseases Pathogens can lead to two major types of diseases: ✓Infectious diseases, illness caused by pathogens and which are transmitted from one host to another. ✓Microbial diseases/ intoxications, which result from the consumption of toxins produced by microbes. CATEGORIES OF MICROBES There are two major categories of microbes: ❖Acellular microbes- They have no cellular components ❖Cellular microbes- Possess cells/ cellular components. SIGNIFICANCE OF MICROORGANISMS ❖ Microbes contribute to oxygen production through photosynthesis even more than plants (e.g., cyanobacteria and algae). ❖ Many microbes are involved in decomposition of dead organisms and waste product of living organisms (e.g saprophytes) ❖ Saprophyte is an organism that lives on dead or decaying organic matter. ✓They contribute to soil fertility by converting organic materials into nitrates, phosphates, and other essential plant nutrients. SIGNIFICANCE OF MICROORGANISM ❖ In aquatic environments, microscopic organisms collectively called plankton serve as the foundation of food chains. ❖ Phytoplankton, the plant-like plankton, produce oxygen and serve as food for zooplankton (tiny animals). ❖Many microbes reside within the intestinal tracts of animals, playing a vital role in digestion. These beneficial microorganisms often produce substances that benefit their host. For instance, E. coli bacteria, commonly found in the human intestine, synthesize vitamins K and B1, which are subsequently absorbed and utilized by the human body. SIGNIFICANCE OF MICROORGANISMS ❖Some bacteria and fungi produce antibiotics that are used to treat patients with infectious diseases. ✓ Antibiotic is a substance produced by a microbe that is effective in killing or inhibiting the growth of other microbes. ❖Microbes are essential tools in genetic engineering, allowing scientists to insert genes into cells to produce specific proteins. ❖Microbiologists have engineered bacteria and yeast to produce valuable substances like insulin, growth hormones, and vaccine components. ❖For many years, scientists have used microbes as cell models to study the structure and function of cells.  Branches of Microbiology Bacteriology: Study of various types of bacteria Phycology: Study of the various types of algae Mycology : Study of various types fungi Virology : Study various types of viruses Parasitology: Study of various types parasites. Immunology : Study of the immune response to various diseases  Microbiology Industries ❑ Clinical microbiology Focuses on diagnosing diseases and determining appropriate treatments by analyzing microorganisms in patient samples ❑ Medical microbiology Is a broader field that includes the study of pathogens, the diseases they cause, and the body's immune response ❑ Food microbiology Ensures food safety by preventing the spread of foodborne diseases through strict quality control measures.  Microbiology Industry ❑ Agriculture microbiology ▪ Farmers uses various strategies to prevent the spread of plant diseases. These methods include using pesticides and rotating crops to disrupt the life cycles of harmful organisms. ❑ Environmental microbiology ▪ Microorganisms play a crucial role in waste management. Sewage treatment plants and compost piles rely on these tiny organisms to decompose organic matter into environmentally friendly substances. Additionally, microorganisms are used to break down pollutants and contaminants. ❑ Industrial microbiology ▪ Focuses on using microorganisms in industries to produce a wide range of valuable products, such as antibiotics, vaccines, solvents, and others. Genetic engineering techniques have enabled scientists to modify microorganisms, leading to the creation of many innovative products. History of Microbiology PIONEERS IN THE SCIENCE OF MICROBIOLOGY ❖ Bacteria and protozoa were the first microbes to be observed by humans ❖ It took about 200 years before a connection was established between microbes and infections. ❖ Many individuals contributed to the present understanding of microbes in the last 400 years  Anton van Leeuwenhoek (Dutch merchant) (1632-1723) ❖He is known as the Father of microbiology ❖ He was the first person to see a live bacteria and protozoa. ❖The protozoa he observed was Giardia lamblia in his own stools. ❖He invented the first microscope known as single lens microscope or simple microscope ❖He used his microscopes to examine almost anything he could get his hands on ❖He observed various tiny living creatures, which he called animalcules  Louis Pasteur (French Chemist) (1822 – 1895) ❖While investigating wine spoilage, Pasteur discovered the role of microorganisms in fermentation. He demonstrated that different microbes produce distinct fermentation products, such as yeast converting glucose into alcohol (ethanol) and bacteria transforming it into acetic acid. ❖He discovered the terms aerobes (microbes that requires oxygen) and anaerobes (microbes that don’t require oxygen). ❖He developed the pasteurization process-used to kill pathogen in many types of liquids, by heating up to 65 ºC for 30 sec.  Louis Pasteur (French Chemist) (1822 – 1895) ❖He contributed to the germ theory (specific microbes cause specific diseases. ❖He contributed to the changes in the hospital practice to minimize the spread of diseases by pathogens ❖He developed vaccines for chicken pox, anthrax and swine erysipelas (skin disease). ❖He developed a vaccine to prevent rabies in dog and later used to treat human rabies Robert Koch (German physician) (1843 – 1910) ❖He made significant contribution to the germ theory of disease. E.g proved that Bacillus anthracis cause anthrax. ❖ Discovered that B. anthracis produces spores, capable of resisting adverse conditions ❖Robert Koch and his colleagues established an experimental procedure (Koch Postulate) to prove that a specific microbe is the cause of a specific infectious disease.  Robert Koch (German physician) (1843 – 1910) ❖ Developed methods of fixing, staining and photographing bacteria. ❖ Developed methods of cultivating bacteria on solid media. ❖ He discovered the bacterium ( Mycobacterium tuberculosis) that causes tuberculosis and bacterium ( vibrio cholera) that causes cholera. ❖Koch work on tuberculin ( a protein derived from M. tuberculosis) ultimately led to the development of a skin test valuable in diagnosing tuberculosis. Alexander Fleming (Scottish Biologist) (1881 – 1955) IN 1929, he discovered the world’s first antibiotic; Penicillin, while culturing bacteria.  Edward Jenner (British physician) (1749 – 1823) ❖ Edward Jenner, was named the “father of immunology” because; ❖ He was the first to use vaccination against an infectious disease in a scientific manner. ❖ He observed that people in rural areas exposed to cowpox were immune to smallpox ❖He performed the first successful vaccination against smallpox with tissue from cowpox lesions.  Joseph Lister (British surgeon) (1827 – 1912) ❖ He discovered airborne diseases ❖He also discovered the antiseptic techniques in surgery- a way to prevent infection in wounds during and after surgery. ❖He had observed that postoperative infections were greatly reduced by using a chemical agent such as diluted carbolic acid during surgery to sterilize the instruments and to clean the wounds.  Alexandre Emile Jean Yersin ❖ He was a former student of Louis Pasteur and Robert Koch who in 1894 discovered the bacterium that causes plague, and this bacterium was later named Yersinia pestis. Microscope Types of Microscope  Light microscopes Simple Microscope A microscope with a single lens for magnification. Can magnify images about 3 to 20 times larger than object actual size Compound Microscope ✓ Is a microscope that contains more than one magnifying lenses. It can magnify objects about 1,000 time  Electron Microscope ✓ High resolutions microscopes ✓ Magnify extremely small microbes e.g. viruses ✓ Electron microscopes cannot be used to observe living organism- Organism have to be killed during the specimen-processing procedures. ✓ Provide 2 dimensional images Two types: ✓ Transmission Electron microscope ✓ Scanning Electron microscope  Atomic Force Microscope ✓ Neither Transmission nor Scanning electron microscopes enable you to observe live microbes because of required specimen - processing procedures and Subjection of the specimens to vacuum ✓ Atomic Force Microscopy (AFM) enable scientist to observe living cells at high magnification and resolution ✓ AFM provides three-dimensional images Fundamental chemistry of microbiology  Introduction ▪ Chemistry is a foundational pillar of microbiology. Understanding the chemical principles underlying cellular processes is essential for a deep comprehension of microbiology. Why chemistry is so Important? ▪ Understanding the chemistry of proteins, carbohydrates, lipids, and nucleic acids provides insights into how cells operate. ▪ Many infectious diseases occur at the molecular level. The pathogens interact with host cells through chemical processes. Understanding these interactions helps in developing effective treatments and prevention strategies.  Introduction of Infection Process The infection process involves various chemical reactions, such as ▪ The attachment of pathogens to host cells ▪ The release of toxins, and ▪ The immune response. ▪ A strong knowledge of chemistry enables us to comprehend these processes in detail.  Levels of Organization ▪ The human body has many levels of structural organization:  Fundamental chemistry of Microbiology ▪ All aspects of a microorganism's existence, from its functions to its survival, are influenced by its chemical composition. ▪ Cells are composed of large biological molecules also known as macromolecules such as DNA, RNA, proteins, lipids, and carbohydrates. ▪ These macromolecules combine to form various cellular structures such as capsules, cell walls, cell membranes, and flagella.  Fundamental chemistry of Microbiology ▪ Macromolecules are made from smaller units called building blocks, such as monosaccharides, fatty acids, amino acids, and nucleotides. ▪ Building blocks are assembled from even smaller molecules like water, carbon dioxide, ammonia, and sulfates. ▪ These smaller molecules are composed of atoms, such as carbon, hydrogen, oxygen, and nitrogen.  Matter ▪ Matter: Anything that occupies space and has mass is considered matter. This includes everything from living organisms to inanimate objects. ▪ Elements: are the fundamental building blocks of matter. They are pure substances that cannot be broken down into simpler substances by ordinary chemical means. Each element has its own unique set of chemical and physical properties.  Atoms ▪ An atom is the basic unit/ building block of an element Atoms are composed of three types of particles: ▪ Protons- positively charged ▪ Neutrons- No charge ▪ Electrons- negatively charged  Element ▪ Element – a pure substance composed entirely of the same type of atoms.  Common Element ▪ Oxygen, carbon, hydrogen, and nitrogen are the four elements that make up the majority of all living organisms. ▪ Together, they constitute approximately 96% of the human body weight. ▪ These elements are essential for the formation of the various biomolecules that make up our cells, tissues, and organs.  Chemical bonding ▪ When elements interact, they can form chemical bonds- which are forces that hold atoms together. ▪ These bonds are relatively strong and require energy to break. ▪ Chemical bonds are formed by the sharing or transferring of valence electrons, which are the outermost electrons of an atom. ▪ The combination of atoms through chemical bonds results in the formation of molecules. ▪ Molecules of elements (when atoms of the same element bond) ▪ Molecules of Compounds (when atoms of different elements bond).  Ionic bond ✓Ionic bonds form when atoms transfers electrons to each others ✓Typically, this occurs between metal and non-metal atoms.  Covalent bond ✓Covalent bonds involve the sharing of electron pairs between two non-metal atoms.  Hydrogen bond ✓ Occur when a hydrogen atom covalently bonded to a highly electronegative atom (like oxygen or nitrogen) experiences an attraction to another electronegative atom.  Metallic bond ✓ Occurs between metal atoms, characterized by the sharing of delocalized electrons among a lattice of positively charged metal ions.  Organic compounds ✓Organic compounds are a group of chemicals that contain carbon and are essential components of living things. ✓Organic compounds always contain carbon atoms bonded together to form a backbone structure. ✓The bonds between carbon atoms and other atoms in organic compounds are covalent bonds. ✓They are typically found in living organisms or their products. ✓ There's a vast diversity of organic compounds, ranging from simple molecules like methane to complex biomolecules like proteins and DNA.  Carbon forms ✓ Carbon is the primary major for all living systems. It occur naturally in 3 forms as: ▪ Amorphous Carbon: This form of carbon is non-crystalline and has various industrial uses, such as in inks, paints, rubber products, and batteries. ▪ Also known as lampblack, gas black, channel black and carbon black ▪ Graphite: Known for its softness, graphite is used as a lubricant and in the production of steel and pencils. ▪ Diamond: Renowned for its hardness, natural diamonds are used for jewelry, while artificially produced diamonds are used in industrial applications like saw blades.  Carbon bonds ✓ Carbon atoms can form single, double, and triple bonds with other atoms, including other carbon atoms. ✓ When other elements combine with carbon atoms, they create new organic compounds. For example, hydrocarbons are formed when only hydrogen atoms bond to carbon. ✓ Multiple carbon atoms can link together to form longer chains, which can lead to molecules with varying properties. ✓ Longer carbon chains tend to form liquids or solids, while shorter carbon chains, especially hydrocarbons, are often gases.  Biological molecules ✓ Also known as macromolecules or organic molecules ✓Both use carbon as their backbone Four types:  Carbohydrates ✓ Carbohydrates are made of carbon, hydrogen, and oxygen atoms. ✓Carbohydrates are a readily available and efficient source of energy for organisms. ✓Cells can both break down carbohydrates for energy (catabolism) and build them up for storage (anabolism). ✓Building Blocks: Simple sugar (saccharides) ✓Glycosidic bonds are the covalent bonds that link monosaccharide units together to form larger carbohydrates, such as disaccharides and polysaccharides.  Types of carbohydrates There are 3 major types ✓Monosaccharides- simple sugar ✓Disaccharides- made up of two monosaccharides ✓Polysaccharides- combination of many monosaccharides molecules  Monosaccharides ✓They are simple sugar  Disaccharides ✓Made up of two monosaccharides ✓The bond holding the two monosaccharides together is called glycosidic bond  Polysaccharides ✓Combination of many monosaccharides molecules  Lipids ✓Lipids are essential constituents of almost all living cells ✓ They store energy, provide insulation, and form cell membranes ✓Most lipids are insoluble in water but soluble in organic solvent such as ether, chloroform and benzene. ✓Building blocks: Fatty acids and glycerol ✓Fatty acids can be saturated or unsaturated ✓Saturated fatty acids contain only single bonds between carbon atoms ✓Unsaturated fatty acids contain one or more double bonds between carbon atoms  Types of Lipids ✓Waxes- simple lipids, example earwax- that protect ear canal ✓Fat and oils (triglycerides) ✓Phospholipids- that makes up a plasma membrane ✓Steroids- common example is cholesterol which is a precursor of vitamin D, testosterone, oestrogen, progesterone etc. ✓Prostaglandins- plays a role in reproduction (found in semen) and inflammation (at tissue injury site)  Proteins ✓Protein are among the most essential chemicals in all living cells ✓They catalyze chemical reactions (enzymes), provide structural support, transport substances, and act as signalling molecules. ✓Proteins are made up of carbon, hydrogen, oxygen, nitrogen, and sometimes sulfur. ✓Building blocks: Amino acids ✓Proteins differ in size, amino acid sequence, and function. ✓Peptide Bonds: Amino acids are linked together by peptide bonds to form proteins. ✓Proteins are classified into various categories based on their structure and function. Proteins types based on structures  Proteins based on functions ✓ Enzymes- Catalyze chemical reactions within cells. E,g. Lipase, amylase, DNA polymerase. ✓ Structural Proteins- Provide structural support to cells and tissues. E.g. Collagen, keratin, actin, myosin. ✓ Transport Proteins- Carry molecules across cell membranes or throughout the body. Examples: Hemoglobin, albumin. ✓ Storage Proteins- Store nutrients or other substances. E.g. Ovalbumin (in egg white), casein (in milk). ✓ Hormones- Act as chemical messengers to regulate various biological processes. E.g. Insulin, growth hormone. ✓ Defense Proteins- Protect the body from pathogens or harmful substances. E.g. Antibodies. ✓ Motor Proteins- Generate movement within cells or tissues. E.g. Myosin (in muscle cells), kinesin and dynein (involved in intracellular transport)  Nucleic acids ✓These are genetic materials of an organism ✓ They store and transmit genetic information. ✓Building blocks: Nucleotides ✓Nucleic acids are made from nucleotide joined together by a hydrogen bond A nucleotide consist of: ✓Nitrogenous base ✓pentose sugar ✓phosphate  Types of Nucleic acids There are two types: ✓DNA ✓RNA  Essentials of metabolism ✓ Metabolism is the sum of all chemical reactions that occur within a living organism. ✓ It involves the breakdown of molecules (catabolism) to release energy and the synthesis of new molecules (anabolism) to build and repair tissues. ✓ Chemical reaction- is the formation or breaking of chemical bonds Most metabolic reactions categories: ✓ Catabolism ✓ Anabolism  Types of metabolism ✓ Catabolism refers to breaking of complex molecules into smaller ones in a cell. It involve the breaking of bonds, which releases energy. ✓ Anabolism refers to building of complex molecules using smaller ones in a cell. It involve the formation of bonds, which requires energy  Energy molecule ✓The major energy molecule in cells is ATP (Adenosine Triphosphate) ✓It contains the nitrogenous base adenosine, a ribose sugar, and a chain of three phosphates bonded to the ribose sugar. Cellular energy How ATP stores and releases energy for chemical metabolism: ✓Store: by adding a phosphate group ✓Release: By removing a last phosphate Thank you