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Type III Secretion System

often written Type III secretion system and abbreviated TTSS or T3SS are complex bacterial structures that provide Gram-negative pathogens with a unique virulence mechanism. They enable them to inject with a needle like structure a bacterial effector proteins (a cell that acts in response to a stimulus) directly into the host cell and help the bacteria to infect the host cell. The term was coined in 1993. Many animal and plant associated bacteria possess similar T3SSs and the activity of their T3SSs correlate closely with infection progression and outcome in humans. There are several different T3SSs including those researched by T3 Bioscience, ie, the human pathogen Pseudomonas aeruginosa and the plant pathogen Erwinia Amylovora that causes the fire blight disease. In the past antibiotics were effective against these bacteria, however, by now antibiotic-resistant strains constantly emerge, posing a threat to humanity.