Structure of the Neisseria Adhesin Complex Protein (ACP) and its role as a novel lysozyme inhibitor.
Structure of the Neisseria Adhesin Complex Protein (ACP) and its role as a novel lysozyme inhibitor.
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DOI：
10.1371/journal.ppat.1006448
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发表时间：
2017-06
期刊：
影响因子：
6.7
通讯作者：
Christodoulides M
中科院分区：
文献类型：
--
作者：
Humbert MV;Awanye AM;Lian LY;Derrick JP;Christodoulides M
致病性和共生性奈瑟氏菌产生一种粘附素复合蛋白，该蛋白首先在脑膜炎奈瑟氏菌 (Nm) 中被表征为一种具有疫苗潜力的新型表面暴露粘附素。在当前的研究中，重组 (r)Nm-ACP I 型蛋白的晶体结构被确定为 1.4 Å 分辨率：折叠类似于八链 β 桶，由第一条 (Cys38) 和最后一条 (Cys121) β 链之间的二硫键稳定。连接β4-β5和β8-β1的主链氢键很少，因此结构分为两个四链反平行β-折叠(β1-β4和β5-β8)。计算的表面静电荷分布表明，β1-β4 片面主要是碱性的，而 β5-β8 片材是非极性的，除了 β4 和 β5 之间的环。 rNm-ACP 和淋病奈瑟菌-ACP 蛋白浓度≥0.25 μg/ml 在 24 小时内显着抑制人溶菌酶 (HL) 的体外活性约 80-100% (P<0.05)。鼠抗奈瑟菌 ACP 血清阻断 ACP 抑制并恢复 HL 活性的能力证明了特异性。 ACP 表达赋予对 HL 活性的耐受性，在溶菌酶存在下，脑膜炎球菌和淋球菌 acp 基因敲除突变体的生长显着减少 3-9 倍（P<0.05），这证明了 ACP 表达赋予了对 HL 活性的耐受性。此外，与未经处理的细菌相比，用纯化的 ACP 特异性兔 IgG 抗体处理的野生型乳酸奈瑟氏球菌显示出类似的细菌生长减少倍数（P<0.05）。 Nm-ACPI 在结构上与溶菌酶抑制剂的 MliC/PliC 蛋白家族相似。然而，奈瑟菌 ACP 蛋白与这些抑制剂的一级序列相似性<20%，并且不共享任何与溶菌酶识别相关的保守 MliC/PliC 序列基序。这些观察结果表明，奈瑟氏菌 ACP 采用不同的溶菌酶抑制模式，并且 ACP 抑制溶菌酶活性的能力对于致病性和共生奈瑟氏菌生物体的宿主定殖可能很重要。因此，ACP 代表了开发奈瑟菌疫苗和抑制宿主-病原体相互作用的药物的双重目标。奈瑟菌属包含两种主要的人类病原体：脑膜炎奈瑟菌 (Nm) 引起脑膜炎和败血症，淋病奈瑟菌 (Ng) 引起性传播疾病淋病。此外，该属还含有大量共生生物，包括 N.lactamica (Nl)。所有这些生物体的共同点是能够定植暴露的粘膜上皮。最近，我们在奈瑟菌属中发现了一种新型的表面暴露粘附素，即粘附素复合蛋白（ACP），它也能够在小鼠体内产生功能性杀菌抗体反应。在当前的研究中，我们确定了重组 (r)Nm-ACP 的晶体结构，并表明它与细菌溶菌酶抑制剂具有结构同源性。我们证明奈瑟菌 ACP 具有哺乳动物溶菌酶抑制剂的功能，但其机制似乎与其他细菌家族溶菌酶抑制剂不同。 ACP 的表达使奈瑟氏球菌能够发挥作用。耐受人类溶菌酶。我们认为，ACP 介导的溶菌酶活性抑制对于致病性和共生奈瑟氏菌生物体的宿主定植可能很重要，并且 ACP 不仅代表了开发奈瑟氏菌疫苗的目标，而且代表了抑制宿主与病原体相互作用的药物。
Pathogenic and commensal Neisseria species produce an Adhesin Complex Protein, which was first characterised in Neisseria meningitidis (Nm) as a novel surface-exposed adhesin with vaccine potential. In the current study, the crystal structure of a recombinant (r)Nm-ACP Type I protein was determined to 1.4 Å resolution: the fold resembles an eight-stranded β-barrel, stabilized by a disulphide bond between the first (Cys38) and last (Cys121) β-strands. There are few main-chain hydrogen bonds linking β4-β5 and β8-β1, so the structure divides into two four-stranded anti-parallel β-sheets (β1-β4 and β5-β8). The computed surface electrostatic charge distribution showed that the β1-β4 sheet face is predominantly basic, whereas the β5-β8 sheet is apolar, apart from the loop between β4 and β5. Concentrations of rNm-ACP and rNeisseria gonorrhoeae-ACP proteins ≥0.25 μg/ml significantly inhibited by ~80–100% (P<0.05) the in vitro activity of human lysozyme (HL) over 24 h. Specificity was demonstrated by the ability of murine anti-Neisseria ACP sera to block ACP inhibition and restore HL activity. ACP expression conferred tolerance to HL activity, as demonstrated by significant 3–9 fold reductions (P<0.05) in the growth of meningococcal and gonococcal acp gene knock-out mutants in the presence of lysozyme. In addition, wild-type Neisseria lactamica treated with purified ACP-specific rabbit IgG antibodies showed similar fold reductions in bacterial growth, compared with untreated bacteria (P<0.05). Nm-ACPI is structurally similar to the MliC/PliC protein family of lysozyme inhibitors. However, Neisseria ACP proteins show <20% primary sequence similarity with these inhibitors and do not share any conserved MliC/PliC sequence motifs associated with lysozyme recognition. These observations suggest that Neisseria ACP adopts a different mode of lysozyme inhibition and that the ability of ACP to inhibit lysozyme activity could be important for host colonization by both pathogenic and commensal Neisseria organisms. Thus, ACP represents a dual target for developing Neisseria vaccines and drugs to inhibit host-pathogen interactions. The genus Neisseria contains two major human pathogens: N. meningitidis (Nm) causes meningitis and sepsis, and N. gonorrhoeae (Ng) causes the sexually transmitted disease gonorrhoea. In addition, the genus contains a larger number of commensal organisms, including N. lactamica (Nl). Common to all of these organisms is the ability to colonize exposed mucosal epithelia. Recently, we identified a novel surface-exposed adhesin in Neisseria spp., the Adhesin Complex Protein (ACP), which was capable also of generating a functional bactericidal antibody response in mice. In the current study, we have determined the crystal structure of a recombinant (r)Nm-ACP and shown that it shares structural homology to bacterial lysozyme inhibitors. We demonstrate that Neisseria ACP functions as an inhibitor of mammalian lysozyme but the mechanism appears to be different from other bacterial family lysozyme inhibitors. Expression of ACP enables Neisseria spp. to tolerate human lysozyme. We propose that ACP-mediated inhibition of lysozyme activity could be important for host colonization by both pathogenic and commensal Neisseria organisms and that ACP represents not only a target for developing Neisseria vaccines but also drugs to inhibit host-pathogen interactions.
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人类全血和诱变研究中脑膜炎的转录组分析确定了与血液存活有关的毒力因子。
影响因子：
6.7
作者：
Echenique-Rivera H;Muzzi A;Del Tordello E;Seib KL;Francois P;Rappuoli R;Pizza M;Serruto D
通讯作者：
Serruto D
DOI：
10.1021/acs.langmuir.6b00240
发表时间：
2016-04-12
期刊：
Langmuir : the ACS journal of surfaces and colloids
影响因子：
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作者：
Clifton LA;Ciesielski F;Skoda MW;Paracini N;Holt SA;Lakey JH
通讯作者：
Lakey JH
影响因子：
3.7
作者：
Chaudhury S;Berrondo M;Weitzner BD;Muthu P;Bergman H;Gray JJ
通讯作者：
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DOI：
10.1099/00221287-99-2-333
发表时间：
1977-01-01
期刊：
JOURNAL OF GENERAL MICROBIOLOGY
影响因子：
--
作者：
HECKELS, JE
通讯作者：
HECKELS, JE
影响因子：
3.5
作者：
Düring, K;Porsch, P;Gieffers, W
通讯作者：
Gieffers, W