6.11-15 culturing Microorganisms Microbiology

6.11 Microbial Growth in Communities Ecological Associations Symbiosis Parasitism-Pathogenic Mutualism-Both Benefit Commensalism-One Benefits, Other unharmed

6.11 Microbial Growth in Communities Biofilms Cells adhere to each other on a surface Five Stages Initial attachment Irreversible attachment Maturation I Maturation II Dispersion

6.12 Control of Microbial Growth Joseph Lister Very Important in many fields Methods: Heat, Chemicals, Irradiation, High Pressure and filtration Sterilization-kills everything Disinfectants-destroy cell wall or interfere w/ metabolism Antiseptics-Used on living tissue to reduce infection Antibiotics-Broad spectrum and targeted Antibacterials-Bactericidal & Bacteriostatic

6.12 Control of Microbial Growth Rate of Microbial Death

6.12 Control of Microbial Growth Relative Resistance Endospores-Most resistant Infections-Difficult to treat Horizontal gene transfer Antibiotic Resistance-Gram neg. Staphylococcus aureus Fungal-Most susceptible

6.13 Mechanisms of Microbial control Alteration of Membrane Permeability Antimicrobial Drugs Polymyxin & gramicidin

6.13 Mechanisms of Microbial control Damage to Nucleic Acids Bacteriostatic antibiotics Broad Spectrum Stops Bacterial Reproduction Tetracycline, sulfonamides, Spectrinomycin

6.14 Physical Antimicrobial Control Heat High Pressure Autoclave Radiation Low Temperatures Desiccation Freeze-Drying Osmotic Pressure Salt & Sugar Filtration 20-50 nm

6.15 Chemical Antimicrobial control Disinfection Bitrex High-Med-Low Germicides Ethanol, Hydrogen Peroxide, Iodine

6.15 Chemical Antimicrobial control Antiseptics (living) disinfectants (non-living) Air-Bleach & glycols Liquid-Alcohols & Aldehydes Oxidizing Agents-Chlorine & Oxygen

6.15 Chemical Antimicrobial control Biological control Maggot Therapy Probiotics Antibiotics