Undecaprenol phosphate

Assembly of this repeating unit begins with the transfer of a phosphogaladosyl unit from UDP-Gal to the phospho group of the lipid carrier undecaprenol phosphate. 

The structure of undecaprenol phosphate. Isoprene phosphates such as undecaprenol phosphate are important carriers and activators in the synthesis of oligosaccharides. Note the similarities to dolichol phosphate. 

The undecaprenol phosphate functions as a carrier and is acted upon by the series of reactions. 

This lipid carrier is, therefore, identical with, or at least very similar to, the C55 lipid involved in the synthesis of D-mannan in Micrococcus lysodeikticus the latter lipid, also, has two internal, trans, double bonds. The former lipid behaves very similarly to the carrier lipid involved in O side-chain synthesis in Gram-negative bacteria, and can substitute for the latter lipid in the O antigen system. This result is not, however, a rigorous proof of identity, as the M. lysodeikticus system is known to be able to use ficaprenol phosphate as efficiently as undecaprenol phosphate. ... 

Bacterial ([ ]3,[Z]7)-undecaprenol phosphate (Und-P)(42), has been synthesized from traw-geranyl sulfone and isoprenoid building blocks and then conjugated with prototypical glycan chains through pyrophosphate to Und-PP-linked derivatives (43-45, Scheme 9). °... 

The procedure which we used for measuring DolMP is still the only one we have available for small amounts. It is not quite specific, thus ficaprenol phosphate, undecaprenol phosphate and other polyprenol phosphates also act as acceptors when tested with the liver enz5nne. This method of estimation is quite useful since dolichol phosphate is not easy to identify in crude extracts. 

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