Biogenesis of lipoproteins in bacteria.

Abstract

The murein lipoprotein of Escherichia coli was first discovered by Braun and Rehn (1969). Subsequently, the so-called free-form lipoprotein was discovered by Inouye and his coworkers as one of the major outer membrane proteins in E. coli (Inouye et al. 1972). Among many novel features of the structure and biosynthesis of murein lipoprotein is the presence of a lipoamino acid at its NH2-terminus, N-acyl glyceride-cysteine. The NH2-terminal glycerylcysteine serves as the attachment site of two ester-linked fatty acids and one amide- linked fatty acid (Hantke and Braun 1973). The ester-linked fatty acids in lipoproteins are similar in composition to those present in bulk phospholipids, including the presence of cyclopropane fatty acids in murein lipoprotein as well as in phospholipids. Of the amide-linked fatty acids present in lipoprotein, 65% were palmitic acid (Hantke and Braun 1973).