Diferenzas entre revisións de «Peptidoglicano»

In step 7, the UDP–MurNAc is converted to UDP-MurNAC pentapeptide by the addition of five amino acids, usually including the dipeptide <small>D</small>-alanyl-<small>D</small>-alanine.<ref name="white"/> Each of these reactions requires the energy source ATP.<ref name="white"/> This is all referred to as Stage one.
 
Stage two is occurs in the cytoplasmic membrane. It is in the membrane where a lipid carrier called bactoprenol carries peptidoglycan precursors through the cell membrane. Bactoprenol will attack the UDP-MurNAc penta, creating a PP-MurNac penta, which is now a lipid. UDP-GlcNAc is then transported to MurNAc, creating Lipid-PP-MurNAc penta-GlcNAc, a disaccharide, also a precursor to peptidoglycan.<ref name="white"/> How this molecule is transported through the membrane is still not understood. However, once it is there, it is added to the growing glycan chain.<ref name="white"/> The next reaction is known as tranglycosylation. In the reaction, the hydroxyl group of the GlcNAc will attach to the MurNAc in the glycan, which will displace the lipid-PP from the glycan chain. The enzyme responsible for this is transglycosylase.<ref name="white">{{citecita booklibro |authorautor=White, D. |yearano=2007 |titletítulo=The physiology and biochemistry of prokaryates |editionedición=3rd |locationlugar=NY |publishereditor=Oxford University Press Inc.}}</ref>
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== Notas ==
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