Acinetobacter baumannii is an opportunistic pathogen, which has become a rising threat in healthcare facilities worldwide due to increasing antibiotic resistances and optimal adaptation to clinical environments and the human host. We reported in a former publication on the identification of three phopholipases of the phospholipase D (PLD) superfamily in A. baumannii ATCC 19606^T acting in concerted manner as virulence factors in Galleria mellonella infection and lung epithelial cell invasion. This study focussed on the function of the three PLDs. A Δpld1‐3 mutant was defect in biosynthesis of the phospholipids cardiolipin (CL) and monolysocardiolipin (MLCL), whereas the deletion of pld2 and pld3 abolished the production of MLCL. Complementation of the Δpld1‐3 mutant with pld1 restored CL biosynthesis demonstrating that the PLD1 is implicated in CL biosynthesis. Complementation of the Δpld1‐3 mutant with either pld2 or pld3 restored MLCL and CL production leading to the conclusion that PLD2 and PLD3 are implicated in CL and MLCL production. Mutant studies revealed that two catalytic motifs are essential for the PLD3‐mediated biosynthesis of CL and MLCL. The Δpld1‐3 mutant exhibited a decreased colistin and polymyxin B resistance indicating a role of CL in cationic antimicrobial peptides (CAMPs) resistance.

中文翻译：

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鲍曼不动杆菌磷脂酶D的体内合成单溶心磷脂和心磷脂及其对阳离子抗菌肽耐药性的影响。

鲍曼不动杆菌是一种机会病原体，由于增加的抗生素抗性以及对临床环境和人类宿主的最佳适应性，已成为全球医疗机构日益严重的威胁。我们报道在上的磷脂酶d（PLD）超家族中的3个phopholipases识别前出版物鲍曼不动杆菌ATCC 19606 ^Ť在一致的方式作为毒力因子作用蜡螟感染和肺上皮细胞的入侵。这项研究集中在三个PLD的功能上。甲Δ pld1-3突变体缺陷在磷脂心磷脂生物合成（CL）和monolysocardiolipin（MLCL），而删除PLD2和pld3取消了MLCL的生产。的Δ互补pld1-3突变体PLD1恢复CL生物合成证明该PLD1在CL的生物合成有关。在Δ的互补pld1-3突变体要么PLD2或PLD3恢复MLCL和CL生产导致的结论是，PLD2和PLD3在CL和MLCL生产有牵连。突变研究表明，两个催化基序对于PLD3介导的CL和MLCL的生物合成至关重要。该Δ PLD 1-3突变体显示出降低，表明CL的阳离子抗微生物肽中的作用（营地）电阻粘菌素和多粘菌素B抗性。