Introduction to Microbiology Bacteria Virus Fungus Algae Protozoa

Fig.1

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Bacteria

1. Morphology coccus (spherical) bacillus (rod shape) vibrio (curved shape) 1-5 mm, eukaryote 10-100 mm 2. Cell Organization prokaryote; eukaryote plant cell wall: cellulose bacterial wall: peptidoglycan outer membrane: capsule

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Gram Stain

gram positive: simpler walls, primarily peptidoglycan gram negative: less peptidoglycan and more complex Procedure: crystal → violet iodine → ethanol → red dye

Fig.2

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How antibiotics work

1. osmotic pressure ex. penicillin, ampicillin inhibit peptidoglycan synthesis prevent cell wall formation 2. targeting ribosome ex. clarithromycin binding with ribosome block protein synthesis No effect on human

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Disease Streptococcus pneumoniae : pneumonia Helicobacter pylori: gastrointestinal ulcer Salmonella: food poisoning Application in Food and Dairy Products AB drink yogurt A: Lactobacillus acidophilus B: Bifidobacterium S. thermophilus L. bulgaricus

Fig.3

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Virus general morphology DNA or RNA, Capsid (protein coat) 1. isocahedral : 20 triangular faces and 12 verticles 2. helical 3. envelope outside capsid 4. complex virus How viruses replicate

Fig.4

Fig.5

Fig.6

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Viral Diseases in Animals 1. inhibit host DNA, RNA and protein synthesis ex. Adenovirus 2. host cells' lysosomes may be damaged 3. viral proteins are toxic ex. influenza virus 4. bring cancer-causing gene into cell

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Fungi eukaryotes, usually muticellular Yeast unicellular fungus spherical to egg shaped raise bread and ferment alcoholic beverages

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Homework: Please find some examples about how microbiology can affect human life in agriculture, molecular biology, genetics or biochemistry and list references.