Broad-spectrum anti-biofilm peptide that targets a cellular stress response.
Broad-spectrum anti-biofilm peptide that targets a cellular stress response.
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针对细胞应激反应的广谱抗生物膜肽。
DOI：
10.1371/journal.ppat.1004152
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发表时间：
2014-05
期刊：
影响因子：
6.7
通讯作者：
Hancock RE
中科院分区：
文献类型：
--
作者：
de la Fuente-Núñez C;Reffuveille F;Haney EF;Straus SK;Hancock RE
细菌形成称为生物膜的多细胞群落，导致所有感染的三分之二，并表现出对常规抗生素的适应性耐药性增加10至1000倍。目前，还没有批准的药物专门针对细菌生物膜。在这里，我们鉴定了有效的抗生物膜肽1018，其通过阻断（p）ppGpp（生物膜发育中的重要信号）起作用。在不影响细菌生长的浓度下，肽处理完全防止了生物膜形成，并导致革兰氏阴性和革兰氏阳性细菌病原体的代表性菌株中成熟生物膜的根除，所述革兰氏阴性和革兰氏阳性细菌病原体包括铜绿假单胞菌、大肠杆菌、鲍氏不动杆菌、肺炎克雷伯氏菌、耐甲氧西林金黄色葡萄球菌、鼠伤寒沙门氏菌和新洋葱伯克霍尔德氏菌。低水平的肽导致生物膜分散，而较高的剂量触发生物膜细胞死亡。我们假设，肽的作用，以抑制常见的应激反应，在目标物种，和严格的反应，介导（p）ppGpp合成通过酶RelA和SpoT，是有针对性的。与此一致，通过添加丝氨酸异羟肟酸盐或relA的过表达增加（p）ppGpp合成导致对肽的敏感性降低。此外，阻断（p）ppGpp产生的relA和spoT突变复制了该肽的作用，导致四种测试目标物种中生物膜形成的减少。此外，在生物膜生长两天后，通过从在阿拉伯糖诱导型启动子后表达relA的菌株中去除阿拉伯糖来消除（p）ppGpp表达，这与同时添加的肽的作用相反，导致生物膜的损失。NMR和色谱研究表明，该肽作用于细胞，在30分钟内引起（p）ppGpp的降解，并且在体外直接与ppGpp相互作用。因此，我们提出1018靶向（p）ppGpp并标记其在细胞中的降解。靶向（p）ppGpp代表了对抗生物膜相关耐药性的新方法。细菌通过形成生物膜在大多数环境中定居，包括宿主，生物膜对常规抗生素具有极强的（适应性）抗性。生物膜引起至少65%的人类感染，在器械相关感染、体表感染和慢性感染中尤其普遍。目前，抗生素耐药性生物体存在严重问题，因为抗生素耐药性的爆发，我们的整个抗生素库正在逐渐失去效力，再加上缺乏正在开发或进入临床的真正新颖的化合物。因此，生物膜的甚至更大的抗性增加了医生和医学权威所表达的主要关注。因此，迫切需要新的策略来治疗生物膜感染，我们在本研究中展示了一种基于小肽抑制（p）ppGpp的方法，该方法根除了由四种所谓的ESKAPE病原体形成的生物膜，这些病原体被美国传染病学会鉴定为我们社会中最具抵抗力和耐药性的生物体。这里提出的策略代表了在寻找特异性靶向细菌生物膜的新试剂方面的重大进展。
Bacteria form multicellular communities known as biofilms that cause two thirds of all infections and demonstrate a 10 to 1000 fold increase in adaptive resistance to conventional antibiotics. Currently, there are no approved drugs that specifically target bacterial biofilms. Here we identified a potent anti-biofilm peptide 1018 that worked by blocking (p)ppGpp, an important signal in biofilm development. At concentrations that did not affect planktonic growth, peptide treatment completely prevented biofilm formation and led to the eradication of mature biofilms in representative strains of both Gram-negative and Gram-positive bacterial pathogens including Pseudomonas aeruginosa, Escherichia coli, Acinetobacter baumannii, Klebsiella pneumoniae, methicillin resistant Staphylococcus aureus, Salmonella Typhimurium and Burkholderia cenocepacia. Low levels of the peptide led to biofilm dispersal, while higher doses triggered biofilm cell death. We hypothesized that the peptide acted to inhibit a common stress response in target species, and that the stringent response, mediating (p)ppGpp synthesis through the enzymes RelA and SpoT, was targeted. Consistent with this, increasing (p)ppGpp synthesis by addition of serine hydroxamate or over-expression of relA led to reduced susceptibility to the peptide. Furthermore, relA and spoT mutations blocking production of (p)ppGpp replicated the effects of the peptide, leading to a reduction of biofilm formation in the four tested target species. Also, eliminating (p)ppGpp expression after two days of biofilm growth by removal of arabinose from a strain expressing relA behind an arabinose-inducible promoter, reciprocated the effect of peptide added at the same time, leading to loss of biofilm. NMR and chromatography studies showed that the peptide acted on cells to cause degradation of (p)ppGpp within 30 minutes, and in vitro directly interacted with ppGpp. We thus propose that 1018 targets (p)ppGpp and marks it for degradation in cells. Targeting (p)ppGpp represents a new approach against biofilm-related drug resistance. Bacteria colonize most environments, including the host by forming biofilms, which are extremely (adaptively) resistant to conventional antibiotics. Biofilms cause at least 65% of all human infections, being particularly prevalent in device-related infections, infections on body surfaces and in chronic infections. Currently there is a severe problem with antibiotic-resistant organisms, given the explosion of antibiotic resistance whereby our entire arsenal of antibiotics is gradually losing effectiveness, combined with the paucity of truly novel compounds under development or entering the clinic. Thus the even greater resistance of biofilms adds to the major concerns being expressed by physicians and medical authorities. Consequently, there is an urgent need for new strategies to treat biofilm infections and we demonstrate in the present study an approach, based on the inhibition of (p)ppGpp by a small peptide, that eradicates biofilms formed by four of the so-called ESKAPE pathogens, identified by the Infectious Diseases Society of America as the most recalcitrant and resistant organisms in our society. The strategy presented here represents a significant advance in the search for new agents that specifically target bacterial biofilms.
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影响因子：
2.8
作者：
Balzer, GJ;McLean, RJC
通讯作者：
McLean, RJC
影响因子：
2.1
作者：
BETZNER, AS;FERREIRA, LCS;KECK, W
通讯作者：
KECK, W
DOI：
10.1073/pnas.1631248100
发表时间：
2003-08-19
影响因子：
11.1
作者：
Dahl, JL;Kraus, CN;Barry, CE
通讯作者：
Barry, CE
影响因子：
3.2
作者：
He, Huajun;Cooper, Jennifer N.;Raskin, David M.
通讯作者：
Raskin, David M.
影响因子：
3.6
作者：
Aberg, Anna;Shingler, Victoria;Balsalobre, Carlos
通讯作者：
Balsalobre, Carlos