MICR 221 Lecture Notes - Lecture 10: Virulence-Related Outer Membrane Protein Family, Alanine, Gram-Negative Bacteria

• School: Queen's University
• Department: Microbiology and Immunology
• Course: MICR 221
• Professor: Mixed

Document Summary

There are a limited number of outer membrane proteins. Ie) porins: trimer, tube shaped, span the length of the om. Permeability: - porins: ompc and ompf: mainly cations. Allow hydrophilic molecules to pass through the hydrophobic membrane: phoe phosphate inducible. If the cell grows in low phosphate it will produce more phoe. Recognizes maltose: tsx: nucelosides, t6 receptor, tona: ferrichrome (iron source for e coli), t1 receptor. It is beta linked to n-acetyl muramic acid (nam). 4 alternating d and l amino acids connected to nam (a terminal alanine is lost in cross link formation) Third position is a diamino acid (dam) or lysine. *chains of peptidoglycan linked directly by cooh of terminal alanine to amino group of dap or lysine in next chain. I(cid:374) gra(cid:373) (cid:374)egatives, a lot of the dap is (cid:374)ot li(cid:374)ked. So (cid:373)ore is able to bo(cid:374)d to brau(cid:374)"s lipoprotei(cid:374). Penicillins block the transpeptidation reaction (between alanine and dap/ lysine)