In vitro synthesis of peptidoglycan precursors modified with N-acetylputrescine by Cyanophora paradoxa cyanelle envelope membranes.

The photosynthetic organelles (cyanelles) of the protist Cyanophora paradoxa are surrounded by a peptidoglycan wall, modified through amidation with N-acetylputrescine. Cyanelle envelope membrane preparations were shown to catalyze the lipid-linked steps of peptidoglycan biosynthesis as well as the putrescinylation and subsequent acetylation, occurring at the stage of lipid I and/or lipid II.