In Vivo and in Vitro Synthesis of Phosphatidylglycerol by an Escherichia coli Cardiolipin Synthase.

Journal Article (Journal Article)

Phosphatidylglycerol (PG) makes up 5-20% of the phospholipids of Escherichia coli and is essential for growth in wild-type cells. PG is synthesized from the dephosphorylation of its immediate precursor, phosphatidylglycerol phosphate (PGP) whose synthase in E. coli is PgsA. Using genetic, biochemical, and highly sensitive mass spectrometric approaches, we identified an alternative mechanism for PG synthesis in E. coli that is PgsA independent. The reaction of synthesis involves the conversion of phosphatidylethanolamine and glycerol into PG and is catalyzed by ClsB, a phospholipase D-type cardiolipin synthase. This enzymatic reaction is demonstrated herein both in vivo and in vitro as well as by using the purified ClsB protein. When the growth medium was supplemented with glycerol, the expression of E. coli ClsB significantly increased PG and cardiolipin levels, with the growth deficiency of pgsA null strain also being complemented under such conditions. Identification of this alternative mechanism for PG synthesis not only expands our knowledge of bacterial anionic phospholipid biosynthesis, but also sheds light on the biochemical functions of the cls gene redundancy in E. coli and other bacteria. Finally, the PGP-independent PG synthesis in E. coli may also have important implications for the understanding of PG biosynthesis in eukaryotes that remains incomplete.

Full Text

Duke Authors

Cited Authors

  • Li, C; Tan, BK; Zhao, J; Guan, Z

Published Date

  • November 25, 2016

Published In

Volume / Issue

  • 291 / 48

Start / End Page

  • 25144 - 25153

PubMed ID

  • 27760827

Pubmed Central ID

  • PMC5122781

Electronic International Standard Serial Number (EISSN)

  • 1083-351X

Digital Object Identifier (DOI)

  • 10.1074/jbc.M116.762070


  • eng

Conference Location

  • United States