6 major groups studied by microbiologists MCB2004 Study Guide Lesson 1 Summary o Prokaryotes o Eukaryotes Bacteria Archaea Algae Protozo Fungi o Viruses Bacteria o Prokaryotes o Peptidoglycan peptide and sugar keeps the shape only found in bacteria cell walls o Binary fission o For energy use organic chemicals inorganic chemicals or photosynthesis Archaea o Prokaryotes o Lack peptidoglycan o Commonly live in extreme environments o Include Methanogens Extreme halophiles high concentration of salt Extreme thermophiles Fungi o Eukaryotes o Chitin cell walls o Use organic chemicals for energy o Yeasts are unicellular o Molds and mushrooms are multicellular o Eukaryotes o Absorb or ingest organic chemicals o May be motile via pseudopods cilia Protozoa or flagella Algae o Eukaryotes o Cellulose cell walls o Use photosynthesis for energy o Produce molecular oxygen and organic compounds Viruses o Acellular o DNA or RNA genome o Genome is surrounded by a protein coat called capsid o Coat may be enclosed in a lipid envelope o Viruses are replicated only when they are in a living host cell intracellular parasites Microbe info o Microbes are living creatures except for viruses Have proteins nucleic acids lipids sugars same as us chemically Metabolize grow reproduce response to environment o Microbial genomes many are sequenced Allow them to adapt to different environ Genome organism s total genetic content Complete genome sequence known for many species The phage X174 5368 bps was sequenced by Fred Sanger in 1977 The complete genome sequence of a cellular microbe is Haemophilus influenza 2 million bps 1 700 genes in 1995 Over thousands bacteria archaea Tens of thousands of viruses First draft of human genome was published in 2000 o Microbes have greatest diversity of genomes Important for understanding evolutions Microorganisms o Produce fermented foods such as vinegar cheese and bread o Produce industrial chemicals such as ethanol and acetone o Produce medicine e g insulin interferon vaccine and products used in manufacturing e g cellulase o Widely used as tools in biomedical research o Decompose organic waste o Are producers in the ecosystem by photosynthesis o A few are pathogenic disease causing o Knowledge of Microbiology o Allows humans to control growth of microbes o Microorganisms are so small and cannot be seen by unaided eyes o Microorganisms are very diverse 1 is culturable and studied o Microorganisms are helpful but sometimes are harmful Lesson 2 Objectives List the three domains of cellular organisms 1 Prokaryotes 2 Eukaryotes 3 Viruses hypothesis 1665 Compare spontaneous generation and biogenesis o Spontaneous generation living organisms arise from nonliving matter o Biogenesis living organisms arise from preexisting life alternative Identify the contributions to microbiology made by Hooke and van Leeuwenhoek Pasteur Koch Jenner and Fleming o Hooke reported that living things were composed of little boxes or cells o Van Leeuwenhoek described live microorganisms that he observed in teeth scrapings rain water and peppercorn infusions 1673 1723 o Pasteur showed that microbes are responsible for fermentation Microbial growth is also responsible for spoilage of food demonstrated that these spoilage bacteria could be killed by heat that was not hot enough to destroy the flavor of wine milk etc Microbes are responsible for fermentation Fermentation is responsible for the conversion of sugar to alcohol to make beer and wine Pasteurization is the application of high heat for a short time Pasteur made vaccine for rabies and other diseases Pasteur disapproved spontaneous generation o Koch proved that a bacterium causes anthrax and provided the experimental steps Koch s postulates to prove that a specific microbe causes a specific disease 1876 o Fleming discovered the first antibiotic He observed that Penicillium fungus made an antibiotic penicillin that killed bacteria Staphylococcus aureus 1940s Penicillin was tested clinically and mass produced o Jenner first vaccine 1798 Understand Koch s postulates 1 Detect agent in host s with the disease 2 3 4 Re isolate the agent Isolate pure culture agent Induce disease in new host Explain the importance of recombinant DNA technology o is DNA made from two different sources In the 1960s Paul Berg inserted animal DNA into bacterial DNA and the bacteria produced an animal protein o Recombinant DNA technology or genetic engineering involves microbial genetics and molecular biology List some examples of biotechnology that use recombinant DNA technology o Biotechnology the use of microbes to produce foods and chemicals is centuries old o Genetic engineering is a new technique for biotechnology Through genetic engineering bacteria and fungi can produce a variety of proteins including vaccines and enzymes o Gene therapy missing or defective genes in human cells can be replaced o Genetically modified bacteria are used to protect crops from insects and in gene therapy from freezing o We may be able to synthesize new bacteria Synthetic biology o Stem cells List at least four beneficial activities of microorganisms o Bacteria recycle carbon nutrients sulfur and phosphorus that can be used by plants and animals o Bacteria degrade organic matter in sewage o Bacteria degrade or detoxify pollutants such as oil and mercury o Microbes that are pathogenic to insects are alternatives to chemical pesticides in preventing insect damage to agricultural crops and disease transmission o Bacillus thuringiensis bacteria infections are fatal in many insects but harmless to mammals including humans and to plants Define normal microbiota microbiome o Microbes normally present in and on the human body microflora o Normal microbiota prevent growth of pathogens o Normal microbiota produce growth factors such as folic acid and vitamin Describe several infectious diseases and particularly emerging infectious K diseases o Infectious Spanish flu caused by Influenza Virus and killed 40 50 million people worldwide 1918 Seasonal flu Globally 250 000 to 500 000 deaths per year In the US per year o 35 000 deaths mainly among people 65 years or older o 200 000 Hospitalizations o 37 5 billion in economic cost influenza pneumonia o 10 billion in lost productivity Swine influenza o Emerging Avian flu Influenza A virus Primarily in waterfowl and poultry Sustained human to human transmission has not occurred Severe acute respiratory syndrome SARS SARS associated Coronavirus Occurred in
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