A type III secretion system means that a molecular syringe is used through which a bacterium (e.g. certain types of Salmonella, Shigella, Yersinia) can inject nutrients into protist cells. One such mechanism was first discovered in Y. pestis and showed that toxins could be injected directly from the bacterial cytoplasm into the cytoplasm of its host's cells rather than be secreted into the extracellular medium.Salyers, A.A. & Whitt, D.D. (2002). Bacterial Pathogenesis: A Molecular Approach, 2nd ed., Washington, DC: ASM Press.
A type III secretion system means that a molecular syringe is used through which a bacterium (eg certain types of Salmonella Shigella Yersinia) can inject nutrients into protist cells One such mechanism was first discovered in Y pestis and showed that toxins could be injected directly from the bacterial cytoplasm into the cytoplasm of its host's cells rather than be secreted into the extracellular mediumSalyers AA & Whitt DD (2002) Bacterial Pathogenesis A Molecular Approach 2nd ed Washington DC ASM Press