Microbiology 2

• Leeuwenhoek is recognized for his world-changing scientific contributions, including his initial observations of microbial life and his efforts to organize these organisms into logical classification.
• By the end of the 19th century, these organisms were referred to as microorganisms.
• Leeuwenhoek's microorganisms are now grouped into six categories: Bacteria, Archaea, Fungi, Protozoa, Algae, and Small multicellular animals.
• Carolus Linnaeus developed a taxonomic system for naming plants and animals and grouping similar organisms together.
• Bacteria and Archaea are unicellular and lack nuclei, are found everywhere there is sufficient moisture, reproduce asexually, and their cell walls contain peptidoglycan.
• Fungi are eukaryotic, obtain food from other organisms, possess cell walls, and include Molds and Yeasts.
• Protozoa are single-celled eukaryotes, similar to animals in nutrient needs and cellular structure, live freely in water, and are mostly asexual with some sexual reproduction.
• Algae can be unicellular or multicellular, are photosynthetic, have simple reproductive structures, and are categorized on the basis of pigmentation and composition of cell wall.
• Other organisms include Parasites and Viruses.
• Redi, Needham, Spallanzani, and Pasteur are scientists who investigated the concept of spontaneous generation.
• Pasteur's fermentation experiments are significant to our world today and he is considered the Father of Microbiology.
• Koch made seven contributions to the field of microbiology and identified four steps that must be taken to prove the cause of an infectious disease.
• Spallanzani's experiments concluded that Needham failed to heat vials sufficiently to kill all microbes or had not sealed vials tightly enough.
• Koch's experiments involved simple staining techniques, the first photomicrograph of bacteria, and techniques for estimating CFU/ml.
• Redi's experiments, conducted when decaying meat was kept isolated from flies, maggots never developed.
• During the Golden Age of Microbiology, scientists sought answers to four questions: Is spontaneous generation of microbial life possible? What causes fermentation? What causes disease? How can we prevent infection and disease?
• Pasteur developed the germ theory of disease and Robert Koch studied the causative agents of disease (etiology), examining colonies of microorganisms.
• Gram-positive and Gram-negative bacteria can be identified through Gram staining.
• Gram made contributions to the field of microbiology.
• Buchner's experiments demonstrated that fermentation does not require living cells and that enzymes promote chemical reactions, beginning the field of biochemistry.
• Some philosophers and scientists of the past, including Aristotle, believed that living things can arise from nonliving matter, a theory known as spontaneous generation.
• Koch's postulates state that the suspected causative agent must be found in every case of the disease and be absent from healthy hosts, must be isolated and grown outside the host, and when introduced into a healthy, susceptible host, the host must get the disease.
• Pasteur's experiments, which involved "swan-necked" flasks, showed that microbial growth did not occur when the flask was upright, but did occur when the flask was tilted.
• Needham's experiments, which involved beef gravy and infusions of plant material, reinforced the belief that microbes could arise spontaneously.
• Fungus colony (Penicillium) Zone of inhibition (Staphylococcus)The Modern Age of Microbiology is built on asking and answering questions.
• Microbial genetics, molecular biology, recombinant DNA technology, and gene therapy are all part of the Modern Age of Microbiology.
• Pauling proposed that gene sequences could provide understanding of evolutionary relationships and processes.
• Gene therapy involves inserting a missing gene or repairing a defective one in humans by inserting desired gene into host cells.
• Bioremediation uses living bacteria, fungi, and algae to detoxify polluted environments.
• Production of human blood-clotting factor by E. coli to aid hemophiliacs is an example of recombinant DNA technology.
• The Modern Age of Microbiology includes the study of the role of microorganisms in the environment, bioremediation, recycling of chemicals such as carbon, nitrogen, and sulfur, and the prevention of infection.
• Gram's Stain is part of the Golden Age of Microbiology.
• Immunology, the study of the body's defenses against specific pathogens, is part of the Modern Age of Microbiology.
• The Golden Age of Microbiology rejected the concept of spontaneous generation.
• Von Behring and Kitasato discovered chemicals and cells that fight infection in the blood.
• Semmelweis and handwashing are part of the Golden Age of Microbiology.
• Chemotherapy involves the use of drugs to kill microorganisms.
• Nightingale and nursing are part of the Golden Age of Microbiology.
• Lister's antiseptic technique is part of the Golden Age of Microbiology.
• Prevention of infection is a key aspect of the Golden Age of Microbiology.