Staphylococcus aureus Leukocidin LukED and HIV-1 gp120 Target Different Sequence Determinants on CCR5.
Staphylococcus aureus Leukocidin LukED and HIV-1 gp120 Target Different Sequence Determinants on CCR5.
复制标题
金黄色葡萄球菌杀白细胞素 LukED 和 HIV-1 gp120 针对 CCR5 上的不同序列决定因素。
DOI：
10.1128/mbio.02024-16
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发表时间：
2016
期刊：
影响因子：
6.4
通讯作者：
Torres,VictorJ
中科院分区：
文献类型：
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作者：
Tam,Kayan;Schultz,Megan;Reyes-Robles,Tamara;Vanwalscappel,Bénédicte;Horton,Joshua;Alonzo3rd,Francis;Wu,Beili;Landau,NathanielR;Torres,VictorJ
杀白细胞素艾德（Luk艾德）是由金黄色葡萄球菌产生的双组分成孔毒素，其通过靶向趋化因子受体CC趋化因子受体5型（CCR 5）、CXCR 1、CXCR 2和DARC裂解宿主细胞。除了作为LukED受体的作用外，CCR 5还是人类免疫缺陷病毒1型（HIV-1）主要分离株的主要辅助受体，并已被广泛研究。为了比较LukED和HIV-1如何靶向CCR 5，我们分析了它们各自使用CCR 5/CCR 2b嵌合体介导细胞毒性和病毒进入的能力。这些分析表明，CCR 5的第二和第三胞外环（ECL）对于LukED靶向受体并促进细胞裂解是必要的和足够的。相反，CCR 5的第二ECL对于HIV-1感染性是必要的，但不是充分的。CCR 5点突变的分析表明，甘氨酸-163对于HIV-1感染性至关重要，而精氨酸-274和天冬氨酸-276对于LukED细胞毒性至关重要。ECL 2的点突变降低了HIV-1的感染性和LukED的细胞毒性。用LukED处理细胞不干扰CCR 5嗜性HIV-1感染性，表明LukED和病毒包膜糖蛋白使用CCR 5上的非重叠位点。对LukE中点突变的分析表明，边缘结构域中的氨基酸64至69是CCR 5靶向和细胞毒性所需的。综合以上结果，本研究确定了LukED靶向CCR 5的分子基础，突出了HIV-1和LukED与CCR 5相互作用的不同分子相互作用。重要提示双组分成孔毒素被认为在金黄色葡萄球菌成功成为哺乳动物病原体中起着至关重要的作用。杀白细胞素之一LukED是小鼠致死所必需的。在分子水平上，LukED通过与特定细胞受体结合引起细胞溶解。CCR 5是LukED靶向的受体之一，是嗜CCR 5的HIV-1的主要辅助受体。虽然CCR 5和HIV-1的分子相互作用已得到很好的表征，但LukED与CCR 5相互作用的方式尚不清楚。在这项研究中，我们证明了受体特异性是通过CCR 5和LukE上关键结构域之间的独特相互作用而赋予的。虽然HIV-1和LukED靶向相同的受体，但我们的数据表明它们与CCR 5的相互作用不同，突出了宿主-病原体相互作用的分子复杂性。
Leukocidin ED (LukED) is a bicomponent pore-forming toxin produced by Staphylococcus aureus that lyses host cells by targeting the chemokine receptors CC chemokine receptor type 5 (CCR5), CXCR1, CXCR2, and DARC. In addition to its role as a receptor for LukED, CCR5 is the major coreceptor for primary isolates of human immunodeficiency virus type 1 (HIV-1) and has been extensively studied. To compare how LukED and HIV-1 target CCR5, we analyzed their respective abilities to use CCR5/CCR2b chimeras to mediate cytotoxicity and virus entry. These analyses showed that the second and third extracellular loops (ECL) of CCR5 are necessary and sufficient for LukED to target the receptor and promote cell lysis. In contrast, the second ECL of CCR5 is necessary but not sufficient for HIV-1 infectivity. The analysis of CCR5 point mutations showed that glycine-163 is critical for HIV-1 infectivity, while arginine-274 and aspartic acid-276 are critical for LukED cytotoxicity. Point mutations in ECL2 diminished both HIV-1 infectivity and LukED cytotoxicity. Treatment of cells with LukED did not interfere with CCR5-tropic HIV-1 infectivity, demonstrating that LukED and the viral envelope glycoprotein use nonoverlapping sites on CCR5. Analysis of point mutations in LukE showed that amino acids 64 to 69 in the rim domain are required for CCR5 targeting and cytotoxicity. Taking the results together, this study identified the molecular basis by which LukED targets CCR5, highlighting the divergent molecular interactions evolved by HIV-1 and LukED to interact with CCR5.IMPORTANCEThe bicomponent pore-forming toxins are thought to play a vital role in the success of Staphylococcus aureus as a mammalian pathogen. One of the leukocidins, LukED, is necessary and sufficient for lethality in mice. At the molecular level, LukED causes cell lysis through binding to specific cellular receptors. CCR5 is one of the receptors targeted by LukED and is the major coreceptor for CCR5-tropic HIV-1. While the molecular interaction of CCR5 and HIV-1 is well characterized, the means by which LukED interacts with CCR5 is less clear. In this study, we demonstrated that receptor specificity is conferred through unique interactions between key domains on CCR5 and LukE. Although HIV-1 and LukED target the same receptor, our data demonstrated that they interact with CCR5 differently, highlighting the molecular complexity of host-pathogen interactions.