MICR 221 Lecture Notes - Lecture 8: Flagellum, Ribose, Antibody

• School: Queen's University
• Department: Microbiology and Immunology
• Course: MICR 221
• Professor: Eric B Carstens

Document Summary

Flagella rotation: ccw: propels cell forward (run, cw: tumble or twiddle reorientation increased attractant, decreased repellent [good]: runs towards decreased attractant, increased repellent [not good]: increase in tumbles, try to reorient itself. Ccw: form rotating bundle of flagella and move forward. If run going the right way: will be long. If run is going the wrong way, will be long and directions. Mcps (methyl-accpeting chemotaxis proteins) transmembrane proteins, detect attractant: all share extensive homology at c-terminus (cytoplasmic domain) inside clustered at cell poles. 5 mcps well studied (tsr, tar, trg, tap, aer) transmembrane proteins cells, interacts with chemotaxis system: n-terminus distinct (the binding site for attractants) Highly conserved, sending message to chemotaxis system to flagella. Mcps function as large clusters at poles each monomer traverses cytoplasmic membrane twice ternary complex with 2 cytoplasmic che proteins (chea and chew: work cooperatively to modulate chea activity. Figure 14. 21: immuno-electron microscopy using antibodies against mcp clusters.