Assistant Professor Microbiology Syed Yousaf Kazmi Explain the fundamentals of Microbiology Describe the basic characteristics of bacteria, viruses, fungi and parasites Describe microorganisms of medical imp Recall the contributions of Robert Koch and Loius Pasteur Tragedy of Eyam- Mompessons well Plague hit England Villagers decided to stay 260 died of 350 residents Famous rhyme recalls A ring-a-ring of rosies A pocketful of posies A tishoo! We all fall down In 1665, Robert Hook observed various objects with lenses of 25x magnification Used term Cella In 1674, Antony Van Leeuwenhoek cloth merchant in Holland First simple microscope magnification of 200X Coined term Animacules for bacteria from mouth Mid 17 th century-disease occurred due to altered chemical quality atmosphere Mola Aria ( Bad Air) Now is Malaria In 1854 Cholera Epidemic in London Soho district John Snow map plotting of cholera cases Clustering of cases near Broad Street pump Cholera-waterborne not miasma related Louis Pasteur French Chemist observed yeasts in sour wines Heated the wine at 56 o C to kill yeasts( Pasteurization) Germ theory of disease In 1865 cholera hit Paris Filtered water to capture pathogen Anthrax bacillus filterable- deposit did not cause disease Rejected Spontaneous Generation theory once and for all Swan neck flask is still present in France Museum In 1884, Pasteur developed weak strain of chicken cholera-Vaccine Same experiment Anthrax In 1885, successfully immunize young boy against rabies Robert Koch German doctor 1875 Koch injected blood from Anthrax diseased sheep into mice-same symptoms Autopsies- same findings Isolated rod shaped cell-grew in ox eye Microscopy-multiplication till spores Injected spores into healthy mice-anthrax Autopsied mice- observed same bacilli In 1882, Robert Koch isolated bacterium responsible for TB In 1883, he isolated curved shaped bacillus from cholera victims in Egypt and India 350 b large galaxies & > stars in visible universe Microbial universe microorganisms Microbes present everywhere Antartica, Mount Everest, Deep oceans, miles down crust of earth Microbes are living things with usually singe cell Viruses are non cellular Parasites (Helminths ) are multi-cellular Involved in cycling of N, C, S, P etc Photosynthesis, 50%of O 2 Approx 90% of cells in human are microorganisms Only small %-Pathogen Pathogen- Microorganisms with ability to cause disease Bacteria, Viruses, Fungus, Parasites etc Bacteria, Fungi & Parasites have necessary enzymes and equipments for replication and metabolism Viruses depends upon host cell for function Very Minute- Need electron microscope Acellular No nucleus Either DNA or RNA Replicates in host cells only No ribosome No functional cell membrane No cell wall Small- Need simple microscope Prokaryotic No specific nucleus One chromosome only DNA and RNA No membrane bound organelle 70S ribosome Replicate by binary fission Cell membrane without sterol except Cell wall composed of Peptidoglycans Small Eukaryote Proper nucleus, nuclear memb More than 1 chromosome Mitochondria & other cell bound organelle 80S ribosome Cell membrane Ergosterol Complex carbohydrate cell wall Chitin, Mannan, Glucans Aspergillus flavus Small but helminth are macroscopic Eukaryote like fungi except Cell membrane has cholesterol There is no cell wall Giardia lamblia FeaturesVirusesBacteriaFungiParasites Size 0.3-23-1015-25# Cell TypeAcellularProkaryoteEukaryote DNA/ RNAEitherBoth Nucleic acid replication Host cellContinuousG & S phase ReplicationComplexBinary fissionMitosis/ Meiosis OrganelleUses hostNot membrane bound Membrane bound RibosomesNone70S(30S+50S)80S(40S+60S) Cell membEnv/Non env No sterol #Mycoplasma ErgosterolCholesterol Cell wallNonePeptidoglycanChitin, Glucan None A scientist is studying a cell that has mitochondria in its cytoplasm. Which of the following structure will not be present in this cell? 1. Nuclear membrane 2. Ribosome 3. Cell membrane 4. Cell wall containing peptidoglycan