L1-Microbiology in context PDF

Microbiology in context – life, history, and impact Dr Jenny Ritchie [email protected] Learning objectives to understand the role microorganisms played in the...

Microbiology in context – life, history, and impact Dr Jenny Ritchie [email protected] Learning objectives to understand the role microorganisms played in the evolution of life on Earth to understand how the discipline of microbiology contributed to the advancement of scientific knowledge to be able to give some examples of why microorganisms are important MySurrey attendance code: September 2024 Dr Jennifer Ritchie 1  History of our planet 80% of the Earths life history was exclusively microbial Microorganisms have lived on Earth about 3.5 billion years longer than humans Cyanobacteria – first oxygen- producing microorganisms All life belongs to one of three lineages (or domains) – Bacteria, Archaea or Eukarya LUCA = last universal common ancestor September 2024 Dr Jennifer Ritchie Recommended reading: Brock Chapter 1 / Unit 1 2  Why are microorganisms important? September 2024 Dr Jennifer Ritchie 3 Fungi – earth’s primary decomposers and sequesters of carbon Component Biomass (temperate (tonnes per grassland soil) hectare) plant roots 20 - 90 bacteria 1–2 fungi 2–5 earthworms 0 - 2.5 White rot fungi = use hydrolases to degrade cellulose and peroxidases to mineralise lignin Brown rot fungi = break down hemicellose & cellulose (2-step https://doi.org/10.1016/j.scitotenv.2022.152928 process: active O2 species + enzymes) Soft rot fungi = break down hemicellulose and cellulose September 2024 Dr Jennifer Ritchie 4 Fungi – more than primary decomposers Market value £32.5 bn / year Plastic car parts, synthetic rubber and LegoTM are made using itaconic acid derived from a fungus fermented products only a few litter-saprotrophic fungi, which possess a wide variety of enzymes, have the ability to degrade polyurethane citric acid (E330) September 2024 Dr Jennifer Ritchie 5 History of microbiology..I 1600 1700 1800 1900 Hooke 1st observation debate over ‘cells’ (1665) origin of life van Leeuwenhoek (1660- 1860) - live microorganisms observed spontaneous biogenesis generation (life begets life) (life created from non-living material) Drawing of bacteria in 1683. “wee animalcules” September 2024 Dr Jennifer Ritchie 6 Challengers to ‘spontaneous generation’ Francesco Redi (1668) Italian physician Demonstrated that maggots did not arise spontaneously from decaying meat John Needham (1745) versus Lazzaro Spallanzani (1765) These individuals each performed experiments using boiled media. The key difference that explains their findings relates to how they handled the media. heating cooling incubate GROWTH Needham NO GROWTH Spallanzani September 2024 Dr Jennifer Ritchie 7  http://upload.wikimedia.org/wikipedia/commons/thumb/9/92/Drapeau_de_la_France.png/220px-Drapeau_de_la_France.png Louis Pasteur (1822-1895) Pasteur’s hypothesis – microorganisms present in putrefying material were descendants of those already present in the material or were carried in on dust particles (1861) swan-neck flask experiment was viewed as definitive proof for theory of biogenesis September 2024 Dr Jennifer Ritchie 8 Importance of this change in understanding of how life arose……. Knowledge that life does not arise spontaneously allows: September 2024 Dr Jennifer Ritchie 9  Koch’s postulate provided a set of rules to establish an etiological link between microorganisms and disease German physician Robert Koch (1843-1910) September 2024 Dr Jennifer Ritchie 10 History of microbiology..II 1600 1700 1800 1900 Hooke 1st observation debate over Golden age ‘cells’ (1665) origin of life (1857 – 1914) van Leeuwenhoek (1660- 1860) - live microorganisms observed Pasteur fermentation Ehrlich pasteurisation theory of (1860s) immunity Lister (1890) aseptic surgery (1867) Koch / Hess Koch/Pasteur organisms first Germ theory cultured on media of disease (1881/2) (1876) Drawing of bacteria in 1683. “wee animalcules” September 2024 Dr Jennifer Ritchie 11  History of microbiology..II 1900 2000 Fleming, Sanger & Gilbert Haemophilus Doudna & RJ Petri Watson & Crick Chain & DNA sequencing influenzae Charpentier invented DNA structure Florey (1976-77) 1st microbial CRISPR systems petri dish (1952) Mullis 1st antibiotic sequence for gene editing (1887) (1928/1940) PCR published (2012) (1985) Ruska brothers (1995) Electron microscope (1930s) Werner Arber Restriction enzymes (1978) Tobacco mosaic virus (1935) September 2024 Dr Jennifer Ritchie 12 Concept of scale and size A B C D E 10m 1m 0.1m 1cm 0.1cm 0.1mm 10µm 1µm 0.1µm 10nm 1nm (1mm) (100µm) (100nm) us September 2024 Dr Jennifer Ritchie 13 Naming of organisms: Swedish botanist Carolus Linnaeus Linnaeus established the system of scientific nomenclature for naming organisms in 1735 – this classification system remains at the backbone of all modern biological science Two rules to follow: 1. Each organism has two names, genus followed by species 2. Names are italicised or underlined e.g Staphylococcus aureus staphylo – clustered arrangement of the cells coccus – spherical shape aureus – golden colour of the colonies e.g Escherichia coli discovered by Theodor Escherich and describes the bacterium’s normal habitat, the large intestine (colon) After first mention in text, names are shortened to S. aureus and E. coli. September 2024 Dr Jennifer Ritchie 14 What next ? Next: Tomorrow Wednesday 12 noon in AP3&4 Topic: Bacteria (Dr Beste) Friday 9am in AP3&4 Tutorial: review of week 1 topics (Drs Ritchie, Beste) Other resources (in addition to Microbiology textbook) Listen to BBC Radio 4 In our time Microbiology podcast. First released in 2007, it has Melvyn Bragg talking to three of the UKs leading experts Professor John Dupre, Anne Glover and Andrew Mendelsohn, about the history of microbiology Microbiology Society has put together some short pieces on theme of "What is Microbiology?" Prepare for next week: Read the laboratory manual before Tuesday next week Check over lecture notes once released for week 2 lectures September 2024 Dr Jennifer Ritchie 15