Uptake of biotin by Chlamydia Spp. through the use of a bacterial transporter (BioY) and a host-cell transporter (SMVT).
Uptake of biotin by Chlamydia Spp. through the use of a bacterial transporter (BioY) and a host-cell transporter (SMVT).
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DOI：
10.1371/journal.pone.0046052
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发表时间：
2012
期刊：
影响因子：
3.7
通讯作者：
Maurelli AT
中科院分区：
文献类型：
--
作者：
Fisher DJ;Fernández RE;Adams NE;Maurelli AT
衣原体属物种是引起人类和动物疾病的专性细胞内革兰氏阴性细菌病原体。物种间代谢能力的微小变化与宿主和组织的向性有因果关系。衣原体高度保守基因组分析。揭示了必需维生素生物素的代谢与合成（bioF_2ADB）和/或运输（bioY）基因的差异。链霉亲和素印迹证实了衣原体中存在单一的生物素化蛋白。作为阐明不同生物素获取策略需求的第一步，我们检测了来自C.沙眼衣原体434/Bu，其被注释为II型能量偶联因子转运体（ECF）的S组分。II型ECF通常由转运特异性组分（S）和染色体未连接的能量模块（AT）组成。有趣的是，衣原体缺乏可识别的AT模块。利用~ 3 H-生物素和重组E.在表达CTL 0613的大肠杆菌中，我们证明了生物素以高亲和力（先前显示需要AT模块的II型ECFs的特性）和容量（表观K（m）为3.35 nM，V（max）为55.1 pmol×min−1×mg−1）转运。由于衣原体存在于宿主来源的膜泡（称为包涵体）中，因此我们还寻求生物素从细胞质转运到包涵体泡中的机制。免疫荧光显微镜显示，哺乳动物钠多种维生素转运蛋白（SMVT），其中运输硫辛酸，生物素和泛酸进入细胞，本地化的夹杂物。由于衣原体也是硫辛酸和泛酸的营养缺陷型，因此SMVT可能被衣原体破坏，以将多种必需化合物移动到包含物中，其中BioY和另一种转运蛋白将存在以促进转运到细菌中。总的来说，我们的数据验证了第一个BioY从病原体，并描述了一个两步的机制，衣原体运输生物素从宿主细胞进入细菌细胞质。
Chlamydia spp. are obligate intracellular Gram-negative bacterial pathogens that cause disease in humans and animals. Minor variations in metabolic capacity between species have been causally linked to host and tissue tropisms. Analysis of the highly conserved genomes of Chlamydia spp. reveals divergence in the metabolism of the essential vitamin biotin with genes for either synthesis (bioF_2ADB) and/or transport (bioY). Streptavidin blotting confirmed the presence of a single biotinylated protein in Chlamydia. As a first step in unraveling the need for divergent biotin acquisition strategies, we examined BioY (CTL0613) from C. trachomatis 434/Bu which is annotated as an S component of the type II energy coupling-factor transporters (ECF). Type II ECFs are typically composed of a transport specific component (S) and a chromosomally unlinked energy module (AT). Intriguingly, Chlamydia lack recognizable AT modules. Using 3H-biotin and recombinant E. coli expressing CTL0613, we demonstrated that biotin was transported with high affinity (a property of Type II ECFs previously shown to require an AT module) and capacity (apparent K(m) of 3.35 nM and V(max) of 55.1 pmol×min−1×mg−1). Since Chlamydia reside in a host derived membrane vacuole, termed an inclusion, we also sought a mechanism for transport of biotin from the cell cytoplasm into the inclusion vacuole. Immunofluorescence microscopy revealed that the mammalian sodium multivitamin transporter (SMVT), which transports lipoic acid, biotin, and pantothenic acid into cells, localizes to the inclusion. Since Chlamydia also are auxotrophic for lipoic and pantothenic acids, SMVT may be subverted by Chlamydia to move multiple essential compounds into the inclusion where BioY and another transporter(s) would be present to facilitate transport into the bacterium. Collectively, our data validates the first BioY from a pathogenic organism and describes a two-step mechanism by which Chlamydia transport biotin from the host cell into the bacterial cytoplasm.
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DOI：
10.1086/652398
发表时间：
2010-06-15
期刊：
The Journal of infectious diseases
影响因子：
--
作者：
Byrne GI
通讯作者：
Byrne GI
影响因子：
3.4
作者：
Barelle CJ;Priest CL;Maccallum DM;Gow NA;Odds FC;Brown AJ
通讯作者：
Brown AJ
影响因子：
3.7
作者：
Aziz RK;Kansal R;Aronow BJ;Taylor WL;Rowe SL;Kubal M;Chhatwal GS;Walker MJ;Kotb M
通讯作者：
Kotb M
影响因子：
8
作者：
Choi-Rhee, E;Schulman, H;Cronan, JE
通讯作者：
Cronan, JE
影响因子：
56.9
作者：
Horn, M;Collingro, A;Wagner, M
通讯作者：
Wagner, M