C-terminal Gly residue

In a separate pathway, MTP synthase is regenerated (grouped within a grey box in Fig. 4.12) by transferring sulfur to the small subunit. In Escherichia coli, MoeB catalyses the adenylation of the carboxyl of the C-terminal Gly residue of MoaD, in a reaction very similar to that catalysed by the El enzyme that activates ubiquitin in the ubiquitin/proteasome pathway referred to earlier. The AMP-activated MoaD is then sulfurated by sulfide transfer from an unknown donor. It is assumed that Cu is inserted directly after dithiolate formation. In the last two steps, adenylated MPT is formed from Mg-ATP, and, finally, in the presence of molybdate (MoOa ), bound MPT-AMP is hydrolysed, Cu is released and Mo is transferred to the MPT dithiolate, and the MoCo cofactor is released. 

A summary of the fragment condensation approach to synthesis of the coiled-coil library is shown in Scheme 10. The library was synthesized in two fragments using Fmoc chemistry the C-terminal fragment (residues 11-27) housed the library positions (labeled X in Scheme 10) and the C-terminal lactam the N-terminal fragment (residues 1-10) contained the Cys-Gly-Gly linker and N-terminal lactam bridge. 

Other proteins are transiently attached to the cytosolic face of the membrane either by amide linkage of a myristate (Cl 4 0) molecule to an N-terminal Gly residue (myristoylated proteins Fig. 2b), or by thioether linkage of a 15-carbon farnesyl or a 20-carbon geranylgeranyl polyunsaturated hydrocarbon to a C-terminal Cys residue (prenylated proteins Fig. 2c). Farnesyl and geranylgeranyl are synthesized from isopentenyl pyrophosphate, the precursor of cholesterol (see Topic K5). Some proteins are also modified on Cys residues with covalently attached palmitate (Cl 6 0) (palmitoylated proteins). These include some with membrane-spanning polypeptides (Fig. 2d), some prenylated proteins and some myristoylated proteins. 

Glucagon-like peptide 1 (GLPl) GLP-1 receptor 30- and 31-residue peptide amide differed by a C-terminal Gly Stimulate insulin secretion Solid-phase V -Fmoc chemistry... 

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