BSCI223 Elvis Mars Water on mars water is essential for life it was and still is on mars this raises the possibility there was life on mars at sometime Is earth the only place that life has developed on other places then earth MICROBIAL LIFE 1 Moons can be supported in keeping life on life 2 IMAGINE you are the DuPunt Chemical company 1 Collect soil samples and return to earth 2 ELVIS a robot for soil collection on mars 3 Gravity on mars makes it harder to collect soil then the moon 4 ELVIS2 How it helped when he looked like the person 5 ELVIS2 successfully got soil yet the robot was covered in goo and it didn t look like Elvis anymore 6 Lycria was turned into the puddle of mush 7 Who was responsible for the material degraded DuPont 8 Polyurethane was the chemical that made up the suit by DuPont 9 Boss is upset that this is due to substandard materials 10 Boss suspects germs 11 Find out whether microbes degraded the polyurethane suit in ELVIS a Hypothesis i The degradation of the polyurethane products was caused by a microorganism or isms present in the soil samples caused by ELVIS Microscopy 1 Contrast unstained micro organisms are unstained 2 Differences in intensity between objects 3 Determining resolution 4 Staining increases contrast 5 Light increases contrast Light microscopy 6 Bright field microscopes a Compound microscopes i Series of lenses for magnification ii Light passes through iii 25 objective x10 ocular 250 1 parts LAB 2 when light passes from air to glass or water or water etc the light path is bent iv Light microscopy 1 Dark field microscopes 3 focal point where the light passes and FLIPS the image 180 degrees 4 how do images change a object on one end image on the other angle through the focal point and one though the point straight GO TO WEBSITE AND REVIEW 5 immersion oil same refraction index as glass light can move staing through the oil as if its glass then prevents the air from being there thus not distorting the view a Best for observing pale objects b Only light rays scattered by the specimen enter objective lens c Specimen appears light against dark d Increases contrast 2 Little light enters into the sample light is refracted continues up through the objection lenses 3 2 types of light microscopy a phase contrast microscope b differential interference contrast microscope What might limit your ability to see micro organisms under a light Wavelength Resolving power Contrast in sample Magnification of sample 1 Light microscopy a Fluorescent Microscopes i Direct UV light ii Specimen radiates energy back as a longer visible wavelength iii UV light increases resolution and contrast iv Some cells are naturally florescent others must be stained v Immunofluorescence take antibodies and see what foreign molecules microorganisms are then tagged with a fluorescent die to identify pathogens and make visible variety of proteins b Confocal microscopes i Use dyes ii UV layers to illuminate florescent chemicals in a single plane iii Resolution increases because emitted light passes through pinhole iv Computer constructs 3D images v OVERLAYING IMAGES LETS YOU SEE WHERE CELLS ARE 2 Electron microscopy COMPARED TO OTHERS a Wavelengths smaller then 200 nm b Greater resolving power and magnification c Magnifies objects 10 000X to 100 000X i 2 types transmission electron microscopes 1 2 scanning electron microscopes Vital Activities and roles of Microbes Support all living things Nitrogen fixation take nitrogen molecules and convert to usable organically molecules Replenish Oxygen on earth Degrade inorganic waste materials destroy leaves and litter in organisms NOT ANIMAL that degrades dead carcass Genetics biochemical principals and metabolism 3 75 million years ago say that microorganisms were present changes in layers of rock more organic material then before Early micro organisms no longer exist Grew in the absence of air oxygen methane and Co2 Grew at very high temperatures Look down at the bottom of the ocean volcanic vents Microbial life lives around there pretty indestructible 235 degrees F is the highest they grow at Lecture 3 1 about 7 billion people 2 macdonals claims to have sold 200 billion 3 national debt 17 trillion 4 stars 10 24 5 BACTERIA 5X10 30 a Microbial growth 6 Microbes are found in a Water b Soil c Air d Bottom ocean e In on all surfaces 7 Some extremes bacteria has been cultured at a Low pH b Some water c CAN HAVE a neg pH log number of protons in a solution 8 Ubiquity a Numbers bacteria are the most prevalent b Places bacteria are found in extremes of environments a 1 of bacteria that we know about comprises the total bacteria in the 9 Bacteria model life form universe 10 Classify Microbes a Unclassified microbes are studied and placed into categories b Phenotypic shape size color mobility what environment it is found in Group them together and come up with trees of microorganisms c Phylogenetic rRNA analysis i Method by Carl Woese 1970 ii Found there are 3 domains 1 Bacteria prokaryote 2 Archea prokaryote 3 Eukarya eukaryotes d Classification scheme MEMORIZE i Strains of bacteria have largely the same phenotypic ii Bacteria do not interbread so you only have physiological properties characteristics 11 Taxonomy grouping organisms a CLASSICAL VERSUS MODERN TECHNIQUE i Classical 1 Superficial features 2 Differential features phenotypes ii Modern techniques 1 Contents of DNA genotype 2 Specific genes 16s rRNA b Why use rRNA i It is ubiquitous anything that is a cell has ribosomes therefor has rRNA c Ribosomes 2 subunits come together to form larger i Prokaroytes 1 5 2 23 3 6 ii eukaryotes iii Tree 1 16s way to mark off how many gene changes happen between organisms 2 18s iv 16s RNA acts as a scaffold as a place for proteins to attach 1 Compare sequences and se where the sequence differ in order to see the differences count and make a tree 2 DNA changes over time 12 Tree 13 Describing a new organism a Name is according to rules b Genus and species c Report characteristics in Bergey s Manual available in the library d SAR11 is estimated to make up 50 of all aquatic bacteria 14 Typical bacterial cell a Have i Ribosomes ii Cytoplasm iii Nucleoid iv Glycocalyx 1 Protein outer coating 2 Post defense 3 Not every cell forms v Cell wall vi Cell membrane vii Flagellum 1 Not in all cells 2 Different then eukaryotic flagella 3 motility viii Inclusion b DN inside bacterium floats inside cytoplasm c RNA polymerase makes RNA and interact in cytoplasm d Cell membrane