Discovery of nanopillars on the surface of the insect wings had led to the understanding of its bactericidal property. Nanopillar topography is deterrent to only those bacteria that are attached, or in close contact with the nanopillars. The present study investigated the variation in the viability of Pseudomonas aeruginosa strains PAO1 (virulent) and ATCC 9027 (avirulent) on the wing surface of dragonfly (Pantala flavescens). Viability study indicated that only 0.2% ATCC 9027 survived when incubated with wing for 48 h in Phosphate buffered saline, while under the same conditions 43.47% PAO1 survived. Enumeration of Pseudomonas attached to wing surface suggested that, the number of PAO1 attached on the wing surface was three times lesser than ATCC 9027. Propensity of attachment of P. aeruginosa strains PAO1 and ATCC 9027 on the wing surface investigated using scanning probe microscope indicated that P. aeruginosa ATCC 9027 showed adhesion to 88% of regions and, PAO1 showed adhesion to only 48% regions tested on wing surface. PAO1 survived the bactericidal effect of wing surface by evading attachment. Three clinical isolates tested which showed viability similar to PAO1 strain, also showed lower propensity to attach to wing surface. Transcriptional level analyses using RT-PCR suggested that flagellar genes (fliE and fleS) were downregulated and genes responsible for reversible to irreversible attachment (gcbA and rsmZ) were upregulated in ATCC 9027 than PAO1 on wing surface, indicating relatively higher attachment of ATCC 9027 on wing surface. The study suggests that virulent strains of P. aeruginosa may evade attachment on wing surface. The results gain significance as bioinspired surfaces are being created towards developing antibacterial medical implants and other antibacterial surface applications.

中文翻译：

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铜绿假单胞菌在蜻蜓（Pantala flavescens）翼的纳米柱形地形上的生存策略。

在昆虫的翅膀表面发现纳米柱使人们对其杀菌特性有了更深入的了解。纳米柱形貌仅对附着或与纳米柱紧密接触的细菌具有威慑作用。本研究调查了蜻蜓（Pantala flavescens）机翼表面铜绿假单胞菌菌株PAO1（有毒）和ATCC 9027（有毒）的活力变化。生存力研究表明，在磷酸盐缓冲液中与机翼一起孵育48小时时，只有0.2％的ATCC 9027存活，而在相同条件下，PAO1的存活率为43.47％。枚举附着在机翼表面的假单胞菌表明，附着在机翼表面的PAO1的数量比ATCC 9027少三倍。P附着的倾向。使用扫描探针显微镜对机翼表面的铜绿假单胞菌PAO1和ATCC 9027进行了研究，结果表明，铜绿假单胞菌ATCC 9027粘附于88％的区域，而PAO1仅粘附于48％的机翼表面。PAO1通过逃避附着而幸免于机翼表面的杀菌作用。测试的三株临床分离株显示出与PAO1菌株相似的生存力，也显示出降低附着在机翼表面的倾向。使用RT-PCR进行的转录水平分析表明，ATCC 9027中鞭毛基因（fliE和fleS）被下调，而负责可逆至不可逆附着的基因（gcbA和rsmZ）被上调，高于机翼表面的PAO1，表明ATCC 9027在机翼表面的附着相对较高机翼表面。研究表明，强毒的P。铜绿菌可能逃避机翼表面的附着。随着生物启发性表面正被开发用于开发抗菌医用植入物和其他抗菌表面应用，该结果具有重要意义。