Institute of Legal Medicine, Medical Faculty, University of Cologne, Cologne, Germany.
PLoS One. 2013 Jul 15;8(7):e66862. doi: 10.1371/journal.pone.0066862. Print 2013.
Antibiotic resistance has been reported since the introduction of synthetic antibiotics. Bacteria, such as one of the most common nosocomial pathogens P. aeruginosa, adapt quickly to changing environmental conditions, due to their short generation time. Thus microevolutional changes can be monitored in situ. In this study, the microevolutional process of Pseudomonas aeruginosa PAO1 resistance against a recently developed novel antibacterial zinc Schiff-base (ZSB) was investigated at the proteome level. After extended exposure to ZSB the passaged strain differed in tolerance against ZSB, with the adapted P. aeruginosa PAO1 exhibiting 1.6 times higher minimal inhibitory concentration. Using Two-dimensional Difference Gel Electrophoresis, the changes in the proteome of ZSB adapted P. aeruginosa PAO1 were examined by comparison with the non-adapted P. aeruginosa PAO1. The proteome of the adapted P. aeruginosa PAO1 strain differed significantly from the non-adapted in the abundance of two proteins when both strains were grown under stressing conditions. One protein could be identified as the outer membrane protein D that plays a role in uptake of basic amino acids as well as in carbapeneme resistance. The second protein has been identified as alkyl peroxide reductase subunit F. Our data indicated a slight increase in abundance of alkyl peroxide reductase F (AhpF) in the case of ZSB passaged P. aeruginosa PAO1. Higher abundance of Ahp has been discussed in the literature as a promoter of accelerated detoxification of benzene derivatives. The observed up-regulated AhpF thus appears to be connected to an increased tolerance against ZSB. Changes in the abundance of proteins connected to oxidative stress were also found after short-time exposure of P. aeruginosa PAO1 to the ZSB. Furthermore, adapted P. aeruginosa PAO1 showed increased tolerance against hydrogen peroxide and, in addition, showed accelerated degradation of ZSB, as determined by HPLC measurements.
自从合成抗生素问世以来，就已经有报道称抗生素会产生抗药性。由于其世代时间短，细菌（如最常见的医院病原体之一铜绿假单胞菌）能够迅速适应不断变化的环境条件。因此，可以在原位监测微进化变化。在这项研究中，我们在蛋白质组水平上研究了铜绿假单胞菌 PAO1 对最近开发的新型抗菌锌席夫碱（ZSB）的微进化过程。经过长时间接触 ZSB，传代的菌株在耐 ZSB 方面存在差异，适应的铜绿假单胞菌 PAO1 的最小抑菌浓度提高了 1.6 倍。通过二维差异凝胶电泳，通过与未适应的铜绿假单胞菌 PAO1 相比，检查了适应 ZSB 的铜绿假单胞菌 PAO1 蛋白质组的变化。当两种菌株在应激条件下生长时，适应的铜绿假单胞菌 PAO1 的蛋白质组与未适应的铜绿假单胞菌 PAO1 的蛋白质组在两种蛋白质的丰度上存在显著差异。一种蛋白质可以鉴定为外膜蛋白 D，它在摄取碱性氨基酸以及碳青霉烯类耐药中起作用。第二种蛋白质已被鉴定为烷基过氧化物还原酶亚基 F。我们的数据表明，在 ZSB 传代的铜绿假单胞菌 PAO1 中，烷基过氧化物还原酶 F（AhpF）的丰度略有增加。文献中讨论了 Ahp 丰度的增加是苯衍生物加速解毒的促进剂。因此，观察到的 AhpF 上调似乎与对 ZSB 的耐受性增加有关。在短时间暴露于 ZSB 后，还发现与氧化应激相关的蛋白质丰度发生变化。此外，适应的铜绿假单胞菌 PAO1 对过氧化氢的耐受性增加，并且，如通过 HPLC 测量所确定的，ZSB 的降解速度加快。
