Abstract

Oral Sessions

Day 1, May 19（Wed.）　16:10-16:30　Room A (Zoom)

1A-O1-1610　　PDF

Analyses of gram-negative bacteria component lipid A using LC-QTOF/MS

(¹Osaka Univ., ²Osaka Univ., ³RIKEN IMS, ⁴JKiC, ⁵Keio Univ., ⁶Yokohama City Univ.)
^oNobuyuki Okahashi^1,2,3, Masahiro Ueda^3,4, Fumio Matsuda^1,2, Makoto Arita^3,5,6

A method for the analysis of lipid A, an important component regulating host’s immune function, was developed using LC-QTOF/MS. The sharp peaks of lipid A were observed by employing a metal-free column and high pH basic solvents. This method was applied to the analyses of in vitro cultured gram-negative gut bacteria, E. coli and nine Bacteroidetes strains. The structure of E. coli lipid A was estimated as diphosphoryl hexa-acylated lipid A although many minor and unusual lipid A molecules were also observed in lipid A biosynthetic pathway knockout strains. It was also revealed that Bacteroidetes lipid A was monophosphoryl penta-acylated lipid A but the acyl properties in the main chains were highly heterogeneous.