Structural basis of broad-spectrum β-lactam resistance in Staphylococcus aureus.
Structural basis of broad-spectrum β-lactam resistance in Staphylococcus aureus.
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DOI：
10.1038/s41586-022-05583-3
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发表时间：
2023-01
期刊：
影响因子：
64.8
通讯作者：
Strynadka, Natalie C. J.
中科院分区：
文献类型：
--
作者：
Alexander, J. Andrew N.;Worrall, Liam J.;Hu, Jinhong;Vuckovic, Marija;Satishkumar, Nidhi;Poon, Raymond;Sobhanifar, Solmaz;Rosell, Federico I.;Jenkins, Joshua;Chiang, Daniel;Mosimann, Wesley A.;Chambers, Henry F.;Paetzel, Mark;Chatterjee, Som S.;Strynadka, Natalie C. J.
金黄色葡萄球菌对广谱β-内酰胺类抗生素的耐药性是全球医疗保健的负担。在临床菌株中，耐药性在很大程度上由BlaR1控制，BlaR1是一种受体，通过其传感器结构域的酰化来感知β-内酰胺类药物，诱导跨膜信号转导和面向细胞质的金属蛋白酶结构域的激活。金属蛋白酶结构域在BLAI去阻遏中起作用，诱导BLAZ(β-内酰胺酶PC1)和mecA(β-内酰胺耐药细胞壁转肽酶PBP2a)的表达。在这里，我们单独克服障碍，我们证明了BlaR1直接切割BLAI，这是灭活所必需的，而不需要先前建议的额外成分。BlaR1的冷冻电子显微镜结构-野生型和自切缺陷的F284A突变体，无论是否有β-内酰胺-显示了一个结构域交换的二聚体，我们认为这对内部信号环的稳定至关重要。BlaR1在顺式分子Ser283和Phe284之间发生自发的自我切割，我们描述了自身和Blai切割的催化机制和特异性。这些结构表明，变构信号来自β-内酰胺诱导的排除竞争结合在传感器结构域活性部位的显著细胞外环，驱动随后的动态运动，包括传感器向膜的移动以及伴随着锌金属蛋白酶域的变化。我们认为，这增强了自切割产物从活性中心排出的能力，将平衡转移到允许高效BLAI切割的状态。总而言之，这项研究提供了一种双组分信号受体的结构，它通过直接切割抑制物来调节作用--在这种情况下，是抗生素耐药性。金黄色葡萄球菌BlaR1的冷冻电子显微镜结构揭示了调控广谱β-内酰胺类抗生素耐药性的动态信号状态，这些信号状态是通过切割转录抑制因子BLAI和诱导β-内酰胺酶BLAZ和耐β-内酰胺类细胞壁转肽酶mecA的表达来调节的。
Broad-spectrum β-lactam antibiotic resistance in Staphylococcus aureus is a global healthcare burden. In clinical strains, resistance is largely controlled by BlaR1, a receptor that senses β-lactams through the acylation of its sensor domain, inducing transmembrane signalling and activation of the cytoplasmic-facing metalloprotease domain. The metalloprotease domain has a role in BlaI derepression, inducing blaZ (β-lactamase PC1) and mecA (β-lactam-resistant cell-wall transpeptidase PBP2a) expression. Here, overcoming hurdles in isolation, we show that BlaR1 cleaves BlaI directly, as necessary for inactivation, with no requirement for additional components as suggested previously. Cryo-electron microscopy structures of BlaR1—the wild type and an autocleavage-deficient F284A mutant, with or without β-lactam—reveal a domain-swapped dimer that we suggest is critical to the stabilization of the signalling loops within. BlaR1 undergoes spontaneous autocleavage in cis between Ser283 and Phe284 and we describe the catalytic mechanism and specificity underlying the self and BlaI cleavage. The structures suggest that allosteric signalling emanates from β-lactam-induced exclusion of the prominent extracellular loop bound competitively in the sensor-domain active site, driving subsequent dynamic motions, including a shift in the sensor towards the membrane and accompanying changes in the zinc metalloprotease domain. We propose that this enhances the expulsion of autocleaved products from the active site, shifting the equilibrium to a state that is permissive of efficient BlaI cleavage. Collectively, this study provides a structure of a two-component signalling receptor that mediates action—in this case, antibiotic resistance—through the direct cleavage of a repressor. Cryo-electron microscopy structures of Staphylococcus aureus BlaR1 reveal dynamic signalling states regulating broad spectrum β-lactam antibiotic resistance through cleavage of the transcriptional repressor BlaI and induced expression of the β-lactamase blaZ and the β-lactam-resistant cell-wall transpeptidase mecA.
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DOI：
10.1107/s2059798318009324
发表时间：
2018-09-01
期刊：
Acta crystallographica. Section D, Structural biology
影响因子：
--
作者：
Afonine PV;Klaholz BP;Moriarty NW;Poon BK;Sobolev OV;Terwilliger TC;Adams PD;Urzhumtsev A
通讯作者：
Urzhumtsev A
影响因子：
3.7
作者：
Berzigotti S;Benlafya K;Sépulchre J;Amoroso A;Joris B
通讯作者：
Joris B
影响因子：
56.9
作者：
Daley, DO;Rapp, M;von Heijne, G
通讯作者：
von Heijne, G
影响因子：
2.9
作者：
Blázquez B;Llarrull LI;Luque-Ortega JR;Alfonso C;Boggess B;Mobashery S
通讯作者：
Mobashery S
影响因子：
2.2
作者：
Chen, Shaoxia;McMullan, Greg;Faruqi, Abdul R.;Murshudov, Garib N.;Short, Judith M.;Scheres, Sjors H. W.;Henderson, Richard
通讯作者：
Henderson, Richard