Porins

Definition

Porins are protein channels located in the outer membrane of Gram-negative bacteria. They allow the passive diffusion of small molecules, including nutrients and waste products.

5 Must Know Facts For Your Next Test

1. Porins play a crucial role in antibiotic resistance by controlling the entry of antibiotics into bacterial cells.
2. They are an essential component of the outer membrane of Gram-negative bacteria such as Pseudomonas aeruginosa and Escherichia coli.
3. Mutations in porin genes can lead to changes in permeability, affecting bacterial susceptibility to treatments.
4. Porins can be specific for certain substrates or nonspecific, allowing a wide range of molecules to pass through.
5. They are often involved in infections related to skin and eyes by facilitating the entry and exit of virulence factors.

Review Questions

• What role do porins play in antibiotic resistance?
• How do mutations in porin genes affect bacterial infections?
• Why are porins significant in the context of skin and eye infections?

Related terms

Gram-negative bacteria: Bacteria that have a thin peptidoglycan layer and an outer membrane containing lipopolysaccharides.

Antibiotic resistance: The ability of bacteria to withstand the effects of an antibiotic that once could successfully treat it.

Virulence factors: Molecules produced by pathogens that contribute to the pathogenicity and promote infection.