Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario, Canada.
J Bacteriol. 2011 Sep;193(18):4726-35. doi: 10.1128/JB.01502-10. Epub 2011 Jul 15.
PagL and LpxO are enzymes that modify lipid A. PagL is a 3-O deacylase that removes the primary acyl chain from the 3 position, and LpxO is an oxygenase that 2-hydroxylates specific acyl chains in the lipid A. pagL and lpxO homologues have been identified in the genome of Bordetella bronchiseptica, but in the current structure for B. bronchiseptica lipid A the 3 position is acylated and 2-OH acylation is not reported. We have investigated the role of B. bronchiseptica pagL and lpxO in lipid A biosynthesis. We report a different structure for wild-type (WT) B. bronchiseptica lipid A, including the presence of 2-OH-myristate, the presence of which is dependent on lpxO. We also demonstrate that the 3 position is not acylated in the major WT lipid A structures but that mutation of pagL results in the presence of 3-OH-decanoic acid at this position, suggesting that lipid A containing this acylation is synthesized but that PagL removes most of it from the mature lipid A. These data refine the structure of B. bronchiseptica lipid A and demonstrate that pagL and lpxO are involved in its biosynthesis.
PagL 和 LpxO 是修饰脂 A 的酶。PagL 是一种 3-O 脱酰酶，可从 3 位去除主要酰基链，而 LpxO 是一种加氧酶，可在脂 A 中特定酰基链的 2 位羟基化。博德特氏菌属支气管败血波氏杆菌的基因组中已鉴定出 PagL 和 LpxO 同源物，但在当前的博德特氏菌属支气管败血波氏杆菌脂 A 结构中，3 位酰化，并且未报道 2-OH 酰化。我们研究了博德特氏菌属支气管败血波氏杆菌 PagL 和 LpxO 在脂 A 生物合成中的作用。我们报告了野生型（WT）博德特氏菌属支气管败血波氏杆菌脂 A 的不同结构，包括存在 2-OH-豆蔻酸，其存在依赖于 lpxO。我们还证明，在主要 WT 脂 A 结构中，3 位不酰化，但 PagL 突变导致该位置存在 3-OH-癸酸，表明含有这种酰化的脂 A 被合成，但 PagL 将其大部分从成熟脂 A 中去除。这些数据细化了博德特氏菌属支气管败血波氏杆菌脂 A 的结构，并表明 pagL 和 lpxO 参与其生物合成。
