Lecture 1 Human cancer viruses o 15 of human cancer cases are caused by viruses Life expectancy increase in the USA due to medicine Units of measurement o 1nm 10e 9m o Unaided eye 0 4mm Microbes organisms too small to be seen with the unaided eye Microbe Bacteria Archea Fungi Protoza Algae Viruses Eukaryote Prokaryote x X cell wall Peptidoglycan Peptidoglycan x X X Chitin N A Cellulose Capsid surrounds genome lipid envelope Other Photosynthesis Extreme environments Uni multicellular Absorb organic chemicals Photosynthesis Acellular DNA or RNA need host cell o Living creatures except viruses o Microbial genomes Organisms genetic content Metagenomics Microorganisms o Produce fermented food industrial chemicals medicine o Biomedical research o Dispose organic waste o Can be disease causing Lecture 2 Three domains o Bacteria o Archea o Eukarya Important dates o 1857 1914 Golden age of microbiology o 1665 cells Hooke Cell theory cells Virchow o 1860 s aseptic techniques Lister all living things are composed of cells and come from preexisting o 1876 Koch Specific microbe causes a specific disease o 1940 s Penicillin first antibiotic Flemming Debate over spontaneous generation o Hypothesis that living organisms arise from nonliving matter 1668 Redi s experiment Maggots appeared in jars that were not sealed off to bugs living matter comes from nonliving matter Biogenesis Pasteur s experiment Father of microbiology Swan neck flask experiment proved that microbes exist in nonliving matter Showed that microbes are responsible for fermentation Pasteurization application of high heat for a short time Made vaccine for rabies Koch s Postulates o 1 Detect agent in host with disease o 2 Isolate agent o 3 Induce in new host o 4 Re isolate agent Modern Microbiology o Recombinant DNA made from 2 different sources o Biotechnology Genetic engineering o Botox o Emerging infectious diseases EID new and increasing diseases Stem cells AIDS HIV West Nile virus Mad Cow disease E Coli Ebola Etc o chemotherapy Treatment with chemicals Antibiotics microbes o Synthetic drugs chemicals produced by bacteria and fungi that inhibit or kill other Magic bullet destroy pathogen without harming the host Woese devised a classification of organisms into bacteria eukarya and archea Pasteur disproved spontaneous generation Lecture 3 Biological molecules o Major elements C H O N P S o Organic compounds contain H and C Composition of E coli o 15 protein 70 water Carbohydrates o CH2O n o Monosaccharide 3 7 carbon o Disaccharide 2 monosaccharides Put together by dehydration Broken by hydrolysis o Olgiosaccharide 2 20 monosaccharides o Polysaccharide 20 mono Functions Storage structure lubrication o Cell mambranes o Fuel storage o Vitamins hormones o Triglycerides formed by dehydration Unsaturated one or more double bond o Membranes made of phospholipids Lipids Steroids Proteins o Four carbon rings with OH group o 20 amino acids o Cell structure enzymes transportation bacterial toxins o Peptide bonds dehydration synthesis o Structure Primary structure polypeptide chain Secondary structure folds coils Tertiary structure when coils fold irregulary Quaternary structure 2 or more polypeptides o Conjugated proteins glycoproteins lipoproteins nucleoproteins Nucleic Acid o Nucleotides pentose phosphate nitrogen base o DNA double helix A T C G o RNA single strand A U C G o ATP ribose adenine 3 phosphate groups Dehydration synthesis Hydrolysis makes energy for cell Lecture 4 Microscopy o Simple microscope has 1 lens o Total magnification objective x ocular o Increasing resolution shorter wavelength light o Refractive index light bending ability of a medium Immersion oil used to keep light from bending Microscope Light Resolution 200nm Electron 2nm Power 200x human eye 200 000x human eye Use Small bacteria large viruses Only fixed specimens viruses large molecules Types of light microscopes o Brightfield used to see dark objects light does not enter objective lens o Darkfield light objects against dark background light enters objective lens Observe living unstained specimens o Phase contrast contrast in intracellular structures Useful for bacterial components o Differential Interference Contrast Uses 2 beams of light o Fluorescence Uses UV light to emit visible light Cells may be stained o Confocal Fluorochromes and laser light Makes a 3 D image Types of electron microscopes o Transmission electron Thin sections of specimens Light pathway specimen lens screen Specimen stained with heavy metal salts Electron gun scans surface of specimen Secondary electrons produce image o Scanning electron Preparation of specimens for light microscopy thin film of microbes on slide use of single basic dye classify bacteria into negative or positive o Smear o Simple stain o Gram stain Gram positive killed by penicillin Gram negative are more resistant to antibiotics o Steps of gram stain 1 Application of purple dye 2 Application of mordant iodine 3 Alcohol wash decolorization 4 Application of safranin counterstain pink Gram cells purple Gram cells red after counterstain o Acid fast stain o Special stain For mycobacteria that have waxy cell wall Negative capsules Endospores heat used to stain Flagella need mordant to become visible Lecture 5 Type of cell Nucleus Cell wall Ribosome Division Organelles Prokaryote No true nucleus Peptidoglycan 70S Binary No complex Eukaryote True nucleus No cell wall 80S Mitosis Many complex ER golgi mitochondria etc Basic shapes most bacteria are monomorphic o Coccus spherical o Bacillus rod o Vibrios curved rod o Spirilla helical o Spirochetes helical and flexible o Stella star o Haloarcula square Structures found in ALL bacteria o Cytoplasm o 70S ribosome o Plasma membrane o Nucleoid containing DNA Glycocalyx Flagella o Outside cell wall o Extracellular polysaccharide allows cells to attach o Capsules prevent phagocytosis o Outside cell wall o o Anchored to wall by basal body o Motile cells Rotate flagella to run or tumble H antigens o Axial filaments Endoflagella o Fimbriae and pili Hairlike appendage Allow for attachment Pili transfer DNA Prevents osmotic lysis o Cell wall o Peptidoglycan Polymer linked by polypeptides NAG and NAM Type of wall Stain Type of peptidoglycan of Membranes LPS Teichoic acid Teichoic acid Gram positive Purple Thick One No Yes Gram negative Pink Thin Two Yes endotoxin No o Polyolphosphates covalently linked ends in a glycolipid Acid fast cell envelope Gram Positive o Mycosides and mysolic
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