Molecular DJ - Tir by Molecular DJ published on 2012/11/17 15:03:47 +0000 The amino acid sequence of E. coli Tir converted to music. Correct preparation of food isn't just about making great tasting food; it can stop you from getting ill. Infection with Salmonella and Campylobacter bacteria is associated with eating under-cooked meat, especially chicken. According to the Health Protection Agency, there were over 60,000 cases of Campylobacter food-poisoning last year, and on average 10000 cases of Salmonella per year. Less frequent, but more deadly cases of food poisoning is caused by a type of E. coli that makes a toxin. In Germany in 2011, E. coli contamination of fenugreek seeds resulted in 3700 cases of E. coli poisoning resulting in 48 deaths. Both Salmonella and Campylobacter have the ability to invade our cells. Salmonella is particularly good at this, and can even survive in macrophages, cells that are specifically designed to engulf and kill invading bacteria. Pathogenic E. coli uses a different approach to setting up home inside us: preferring to stay outside our cells, it attaches to the cells lining our intestine, and injects the protein Tir into these epithelial cells using a sort of molecular needle. This protein causes structural re-arrangements of the host cell, resulting in formation of pedestal structures. Colonization by a pathogenic E. coli is bad news, because these strains make harmful toxins called Shiga-like toxins, which can lead to Hemolytic-uremic syndrome. Treatment with antibiotics is tricky, because some antibiotics can actually increase toxin release. Treatment with antibiotics that stop proteins being made and dialysis are used to treat infections. E. coli strains associated with food-poisoning cause re-arrangements within the cells lining our gut, resulting in the formation of pedestal-like structures.