Protein machines types I to IX that export toxins and effectors across bacterial envelopes.
Type III secretion forms a needle injecting effectors into host cells (Salmonella, Yersinia). Type IV can transfer DNA, and type VI delivers toxins to competing bacteria.
Secretion systems deliver toxins or DNA. Needle-like type III injectisome is similar to the flagellar structure. They are drug targets.
Remember: Gram-negatives need systems to cross two membranes.
Protein machines types I to IX that export toxins and effectors across bacterial envelopes.
Bacterial Secretion Systems is one of the 54 topics in Microbiology. It is rated Advanced, so it suits learners who want specialist depth. Related topics in this area include Bacterial Chemotaxis, Bacterial Metabolism, Conjugation.
Agrobacterium uses a type IV system to transfer T-DNA to plants.
Work through the Beginner topics in Microbiology first, such as Microorganisms, Bacteria, Archaea, then return to Bacterial Secretion Systems. Advanced topics assume the Intermediate vocabulary.
The closest topics to Bacterial Secretion Systems are Bacterial Chemotaxis, Bacterial Metabolism, Conjugation, Bacterial Cell Wall. Comparing them side by side is a good way to see how the ideas connect.
Read the summary and the in-depth section, then use the quick check on the interactive lesson for Bacterial Secretion Systems. To practise the whole of Microbiology, use the Microbiology quiz.
Bacterial Secretion Systems: Protein machines types I to IX that export toxins and effectors across bacterial envelopes. Bacterial Chemotaxis: Cells bias a random walk toward attractants by controlling flagellar rotation through CheY. Read both side by side and note what each one explains.
First, read the summary and write the definition in your own words. Second, read the in-depth section and note any example. Third, compare it with Bacterial Chemotaxis and explain the difference aloud. Finally, take the Microbiology quiz and come back to this page for any question you miss.
Cells bias a random walk toward attractants by controlling flagellar rotation through CheY.
🦠 MicrobiologyBacteria are aerobes, anaerobes or facultative, and may be phototrophs or chemotrophs.
🦠 MicrobiologyDirect transfer of DNA, such as a plasmid, between bacterial cells through a pilus.
🦠 MicrobiologyPeptidoglycan gives bacteria shape and strength; Gram-negative species add an outer membrane.
🦠 Microbiology