Lipids modification

Lipid Modifications. Figure 1 Major classes of lipid-modified proteins. 

S-prenylation is the most recent of the four major types of lipid modifications to be described. As with -acylation, S-prenylation is posttranslational. The lipid substrates for these modifications are farnesyl diphosphate and geranylgeranyl diphosphate. The mechanism... 

Palmitoylation is the post-translational lipid modification of cysteine-residues in a variety of proteins. 

Volume 250. Lipid Modifications of Proteins Edited by Patrick J. Casey and Janice E. Buss... 

The following sections present suggested protocols for creating protein-bearing liposomes. Each method utilizes specific lipid modifications to form reactive groups capable of targeting amines, sulfhydryls, aldehydes, or carboxylates on the protein molecules. 

Membranes are asymmetric. Integral membrane proteins can t be washed off. Peripheral membrane proteins can be washed off. Membrane spanning segments and lipid modification (fatty acylation and prenylation), anchor proteins in a fluid bilayer (Singer fluid mosaic model). 

Fig. 19. Lipopeptides with the aminoacid sequence of the Ras C-terminus and the natural or artificial lipid-modifications can be coupled with C-terminally truncated Ras via a maleimi-docaproyl linker. This electrophile reacts with free thiol groups (here, a C-terminal cysteine at the Ras moiety)...

The finding that lipid-modification of Ras, in particular farnesylation, is crucial to its biological activity led to the idea that inhibiting the enzymes re-... 

Inhibition of the lipid modification cascade provides an alternative way to block aberrant signaling pathways and that opportunity can be exploited in anticancer therapy. As part of the growth factor, signaling of the false activation is transmitted by the mutated ras gene encoded proteins (Ras) and ultimately leads to uncontrolled cell growth. These typical GTP binding proteins are also subject to membrane anchoring and the biosynthesis of those Ras proteins can be blocked at the posttranslational prenylation step. 

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