乳铁蛋白多肽嵌合体对铜绿假单胞菌PAO1及PAO-JP2型菌株QS毒力因子的作用

Effect of Lactoferrin-derived peptides chimera on the virulence factors of pseudomonas aeruginosa wild strain PAO1 and mutant strain PAO-JP2

目的观察乳铁蛋白多肽嵌合体(LFchimera)对铜绿假单胞菌PAO1及PAO-JP2型菌株QS毒力因子的影响。方法以PAO1和PAO-JP2为试验菌株,分为A、B、C、D四组。A组:未作任何干预的铜绿假单胞菌PAO1;B组:LFchimera(1μmol/L)干预的铜绿假单胞菌PAO1;C组:未作任何干预的铜绿假单胞菌PAO-JP2;D组:LFchimera(1μmol/L)干预的铜绿假单胞菌PAO-JP2。分别测定毒力因子绿脓菌素(氯仿萃取法)、弹性蛋白酶(弹性蛋白-刚果红法)、胞外蛋白水解酶(偶氮酪蛋白法)。结果和A组各毒力因子(绿脓菌素、弹性蛋白酶、蛋白水解酶)的活性表达(7.03±0.14、0.149±0.009、0.808±0.038)比较,B组铜绿假单胞菌PAO1菌株的表达(3.07±0.13、0.046±0.004、0.325±0.022)明显下降,差异有统计学意义(P<0.05)。C组铜绿假单胞菌PAO-JP2菌株各毒力因子(绿脓菌素、弹性蛋白酶、蛋白水解酶)的活性表达(0.76±0.04、0.015±0.003、0.054±0.006)和D组(0.74±0.05、0.014±0.002、0.053±0.005)比较,差异无统计学意义(P>0.05)。结论 LFchimera可能通过抑制铜绿假单胞菌QS系统减弱其相关毒力因子的活性,从而发挥抗感染作用。

Objective To observe the effect of lactoferrin-derived peptides chimera（LFchimera）on the virulence factors of Pseudomonas aeruginosa wild strain PAO1 and mutant strain PAO-JP2. Methods The wild type strain PAO1 and mutant strain PAO-JP2 of P.aeruginosa were used as experimental strains. In this study, there were four groups. Group A：the wild type strain of P.aeruginosa-PAO1 without any intervention, Group B：the wild type strain of P.aeruginosa-PAO1 with LFchimera（1μmol/L）, Group C： the mutant strain of P.aeruginosa-PAO-JP2 without any intervention, Group D：the mutant strain of P.aeruginosa-PAO-JP2 with LFchimera（1μmol/L）. The expression of their virulence factors was determined respectively, included pyocyanin assay （chloroform extraction method）, elastase activity（Elastin-Congo Red method）and extracellular proteolytic enzyme activity （Azocasein method）. Results Compared with the group A（7.03±0.14,0.149±0.009,0.808±0.038）, the virulence factors production（pyocyanin concentration, elastase activity and proteolytic enzyme activity） in group B （3.07± 0.13,0.046±0.004,0.325±0.022）were all reduced, the difference had statistical significance（P＆lt;0.05）. Pyocyanin concentration, elastase activity and proteolytic enzyme activity had no statistical difference between the group C （0.76±0.04,0.015±0.003,0.054±0.006）and group D（0.74±0.05,0.014±0.002,0.053±0.005） （P＆gt;0.05）. Conclusion LFchimera may weaken activity of virulence factors associated QS by inhibiting Pseudomonas＆amp;nbsp;aeruginosa QS system, which play a role of anti-infection.