Micropara Midterm Coverage 1-9 (PDF)

LESSON 1: THE MICROBIAL WORLD STRUCTURE & ACTIVITIES OF MICROBIAL CELLS Microbial cells Lecture Outline:...

LESSON 1: THE MICROBIAL WORLD STRUCTURE & ACTIVITIES OF MICROBIAL CELLS Microbial cells Lecture Outline: - living compartments that interact with their environment and with other - Microorganisms cells in dynamic ways - Structure and Activities of Microbial Cells - Microscopy and the Origins of Microbiology - The Impact of Microorganisms on Human Society MICROORGANISMS - Also called microbes - Life forms too small to be seen by the naked eye - Diverse in form and function - (inhabit every env that supports life) - (many of these microbes are undifferentiated single-cell organisms) - Live in microbial communities - Their activities are regulated by interactions with each other, with their environments, and with their organisms - (two fundamental types of cells: prokaryotic & eukaryotic) - (Difference between the two: - Size: smaller prokaryotic - Structure: prokaryotic simpler - EU - has membrane-bounded organelles; PR none - EU means true (has true nucleus) - genetic material is usually in the form of DNA found in nucleus and the nucleus is membrane-bounded - PR has NO true nucleus; has nucleus but not membrane-bounded; nucleus can be found in nucleoid - (Similarities) - Has cytoplasmic membrane - it is a permeability barrier - gatekeeper - resp. For substances that go and out of the cell - separates in and outside of the cell - Cytoplasm is the inside of the cell - mixture of macromolecules - has small organic molecules - various organic ions and ribosomes inside cytoplasm - PR and EU both have plasma membrane and cytoplasm - PR and EU have ribosomes - responsible for protein synthesis - PR and EU have genetic material in the form of DNA - In some cases, EU have cell wall but not all RED (ALL CELLS) - Metabolism - Cells take up nutrients. They transport and expel waste materials - w/c is why virus is not considered as living entity/things because it cannot metabolize. It needs a host. It is an obligate parasite - Growth - They can take nutrients from the env. And convert it to new cell materials to form new cells  - Evolution A BRIEF HISTORY OF LIFE ON EARTH - PR is faster due to their size - Viruses can also evolve but cannot do on its own BLUE (SOME) - Differentiation - Can form new cell structures such as spore (certain genera of bacteria only) - Spore formation: env is devoid of nutrients; they become dormant - Communication - Communicate via chemical messenger - Genetic exchange Microbes - oldest form - evolve to perform critical functions to support life - Horizontal type that is common in bacteria - Motility Earth - 4.6 bya - Some has flagella; enables the cell to move Microbial cells - betw. 3.8 and 4.3 BYA Evolved as anoxygenic phototrophic bacteria - able to utilize the energy from the sun to manufacture their own food BUT do not produce oxygen Anoxic Earth - no oxygen has diff gases Oxygen appeared in cyanobacteria - able to undergo photosynthesis, manufacture own food, and undergo oxygenic photosynthesis - convert energy from the sun into usable form of energy and has production of oxygen From anoxic to oxygenated atmosphere called GREAT OXYGENATION EVENT Allowed for evolution of modern UE and algal diversity then we have shelly inv and vascular plants then mammals then humans DOMAINS OF LIFE: BAE - Bacteria, Archaea, and Eukarya Light microscope B A - PRO; E - EU B - 1 kingdom A-1 EU - 4 (Plantae, animalia, protist, and fungi) then divided to phila Origin of their evolution -> LUCA (Last Universal Common Ancestor) MICROSCOPY & THE ORIGINS OF MICROBIOLOGY Robert Hooke - light is focused on the specimen by a glass condenser lens - English mathematician - image is then magnified by an objective lens and an ocular lens for - Coined the term “cell” projection on the eye - Observed cork under microscope - (Visible light is used pass through the specimen then lenses retract the - Authored “Micrographia” devoted to microscopic images light, then image will be magnified) - PARAMETERS IN MICROBIOLOGY Van Leeuwenhoek - Magnification - First to see bacteria under the microscope - Ratio of object, image to its real size - Constructed simple microscope - Resolution - Observed human blood smear - Measure of clarity of image - Contrast Electron Microscope - Made due to resolution problem of light - Resolution is inversely related to wave of light - Beam of electron shorter = better resolution - beam of electrons is used instead of light - electron beam is focused on the specimen by a condenser lens - Coated with gold -  SCIENTIFIC DEVELOPMENT OF MICROBIOLOGY Louis Pasteur (1822 - 1895) - known as the “Father of Microbiology” (aspetic technique, vaccines) - disproved the theory of spontaneous generation *Spontaneous Generation (Abiogenesis) - living organisms could arise from nonliving matter - Started in time of Aristotle and persisted for several centuries SEM - detailed structure of topography (surface) TEM - internal structure of the cell Disadvantage of electron microscope - preparation could kill your cells Francesco Redi - made the setup above (Meat Maggot Exp) 1st open, 2nd sealed, 3rd covered with gauze John Needham - did not believe Redi; published his own; heat broth for minutes then seal it. In one droplet, microbes are alive Lazaro Spallanzani - contradicted Needham. Performed several experiments including Needham’s. The duration of boiling matters to kill microbes  The Paris Academy of Sciences offered a prize to solve the dilemma. 1st setup no maggots/contamination. There's a filter 2nd setup - broke the next and exposed it Edward Jenner (1749 - 1823) - known as the “Father of Immunology” - Vaccine for smallpox BRANCHES OF MICROBIOLOGY - BACTERIOLOGY: study of bacteria - MYCOLOGY: study of fungi John Lister (1827 - 1912) - PHYCOLOGY: study of photosynthetic eukaryotes - known as the “Father of Modern Surgery” - PROTOZOOLOGY: study of protozoa - applied Pasteur’s work and introduced antiseptic techniques in surgery - VIROLOGY: study of viruses Robert Koch (1843 - 1910) - known as the “Father of Bacteriology” THE IMPACT OF MICROORGANISMS ON HUMAN SOCIETY Microorganisms, agriculture, & human nutrition Microorganisms as agents of disease Legumes plants - has associated of rhizobium (nitrogen fixing bacteria) live in root nodules. They convert nitrogen to a usable nitrogenous compounds Legumes give home to these bacterias and food (carbohydrates and lipids) - 1900s leading is microbial diseases Can be used as sustainable agri technique - Today not anymore Animal nutrition - ruminants (cow) - they have 4 stomach chambers Rumen - microbial fermentation - w/c is why they can digest cellulose - produced patty acids and waste products CO2 and CH4 these are greenhouse gases that contribute to climate change  Has fermented products Microorganisms and Industry Probiotics help in digestion Lactobacillus good bacteria Biofuels Microorganisms and Food