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Food Microbiology -Approach and background Expectations Syllabus -Intro to Microbiology. Ryan King, MS Microbial ecology -> systems science -> global change. The Importance of Food Microbiology. Food preparation, safety, decontamination and storage Nutrition and the human microbiome
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Food Microbiology • -Approach and background • Expectations • Syllabus • -Intro to Microbiology
Ryan King, MS • Microbial ecology -> systems science -> global change
The Importance of Food Microbiology Food preparation, safety, decontamination and storage Nutrition and the human microbiome Global change: emerging diseases, threats to food production and biodiversity GMO’s and microbes Water quality and bioremediation
Microbiology: the origins of life • "Therefore I should infer from analogy that probably all the organic beings which have ever lived on this earth have descended from some one primordial form, into which life was first breathed.” – Darwin • LUCA existed some 3.8 Billion Years Ago • New evidence: LUCA more complex than originally believed All of life shares a Last Universal Common Ancestor (LUCA) Microbes are everywhere -Microbes defy traditional reductionist scientific classification systems
Shifting perspectives: endosymbiosis, Gaia, and networks • “Deeper knowledge of bacterial activity is tantamount to greater knowledge of our own bodies and the Earth. A human body contains a natural complement of 10 times more bacterial cells than human cells. Prokaryotes, organisms that lack a cell nucleus like bacteria and archaea, form the majority of the Earth’s biomass and are responsible for cycling its most important nutrients.” – Yuri Gorby (Electromicrobiologist) • “Evolution is no linear family tree, but change in the single multidimensional being that has grown to cover the entire surface of Earth.” – Lynn Margulis • “The entire range of living matter on Earth from whales to viruses and from oaks to algae could be regarded as constituting a single living entity capable of maintaining the Earth's atmosphere to suit its overall needs and endowed with faculties and powers far beyond those of its constituent parts.” – James Lovelock Recent breakthroughs in scientific theory based on microbial evolution have lead to new outlooks on life and evolution Endosymbiosis and Systems Theory
Microbiology begs the question: What is life? The hallmark characteristic of life is AUTOPOIESIS – self-creation Bacteria, prokaryotes, eukaryotes, archaea are autopoietic Viruses use other cells to replicate and do not self maintain Prions replicate be influencing nearby Prp’s to change confirmation – not autopoietic, too Mad cow disease, Scrapie, Cronic wasting syndrome, CJD, Kuru…
Processes that define life are dependent on biochemistry: • Growth • Reproduction/Heredity • Metabolism cell synthesis and release of energy. • Movement and/or irritability • Active transport moving molecules into and out of cells. • Cell support, protection, storage • mechanisms
Fig. 1.4 - Rust myth Microbes and disease: A bad reputation
Review - Food Microbiology Microbes = organisms too small to be viewed with the unaided eye (less than 1mm) Is it alive or non-living? Autopoiesis distinguishes “living” from “non-living” Viruses, Prions, Viroids, other infectious particles are studied in microbiology though they are not autopoietic Endosymbiosis Major contributors - Lovelock, Margulis, Van Leeuwenhoek Timeline of life
Biofilms, Quorum sensing, and Signal Transduction • Microbial Biofilms form naturally on most surfaces – cellular communication between microbes is accomplished by quorum sensing and signal transduction
How bacteria communicate • http://www.ted.com/talks/bonnie_bassler_on_how_bacteria_communicate.html
Important spore forming pathogens in Food Microbio • Bacillus cereus, Clostridium tyrobutyricum= dairy products • C. botulinum – anaerobe, produces neurotoxins; C. estertheticum – anaerobic, psychrophile found in meats = pose risks in chilled, packaged foods • A variety of decontamination treatments used to destroy spore formers