MCB 3020 Lecture Notes - Lecture 2: Atomic-Force Microscopy, Scanning Tunneling Microscope, Endospore
Document Summary
Electron cryotomography: rapid freezing technique provides way to preserve native state of structures examined in vacuum, capsule stain used to visualize polysaccharide capsules surrounding the particular type of bacteria being scanned. Images are recorded from many different directions to create 3-d structures: provides extremely high resolution images of cytoskeletal elements, inclusion bodies, flagellar motors and other viral structures. Cytoskeletal elements, magnetosomes, inclusion bodies, flagellar motors, viral structures. Scanning probe microscopy: scanning tunneling microscope, atomic force. Scanning probe microscopy: scanning tunneling microscope. Magnification up 100 million times, can view individual atoms on the surface of a solid object. Steady electrical current (tunneling current) maintained between microscope probe and specimen in order to magnify to this kind of level of magnification. Up/down movement of probe as it maintains current is detected, used to create image of surface of specimen. Bacterial endospore is one color and vegetative cell is a different color: atomic force microscope.
