Plant carbohydrate scavenging through tonB-dependent receptors: a feature shared by phytopathogenic and aquatic bacteria.
Plant carbohydrate scavenging through tonB-dependent receptors: a feature shared by phytopathogenic and aquatic bacteria.
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DOI：
10.1371/journal.pone.0000224
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发表时间：
2007-02-21
期刊：
影响因子：
3.7
通讯作者：
Arlat M
中科院分区：
文献类型：
--
作者：
Blanvillain S;Meyer D;Boulanger A;Lautier M;Guynet C;Denancé N;Vasse J;Lauber E;Arlat M
TonB依赖性受体（TBDR）是外膜蛋白，主要已知用于革兰氏阴性细菌中铁载体复合物的主动转运。植物病原细菌野油菜黄单胞菌致病变种的基因组分析。campestris（Xcc）预测72个TBDR。这种过度表达在黄单胞菌属物种中很常见，但仅限于少数细菌。在这里，我们表明，一个Xcc TBDR运输蔗糖具有非常高的亲和力，这表明它可能是一个蔗糖清道夫。该TBDR与内膜转运蛋白、淀粉蔗糖酶和调节剂一起作用以利用蔗糖，从而定义了一种新型的碳水化合物利用位点，称为CUT位点，其涉及用于跨外膜转运底物的TBDR。该蔗糖CUT位点是拟南芥完全致病所必需的，显示了其对宿主植物适应的重要性。对Xcc TBDR基因的系统分析和基因组背景调查表明，几个Xcc TBDR属于参与各种植物碳水化合物利用的其他CUT基因座。有趣的是，几个Xcc TBDR和CUT基因座在水生细菌中是保守的，例如新月柄杆菌、精神红腔菌、降解食蟹猴、希瓦氏菌属、鞘氨醇单胞菌属或假交替单胞菌属，它们都具有降解多种复杂碳水化合物的能力，并表现出TBDR过度表达。因此，我们认为TBDR的过度表达和CUT位点的存在表明了碳水化合物的分解能力。因此，CUT位点，这似乎参与了植物病原细菌对它们的寄主植物的适应，也可能在海洋环境中的植物源营养物质的生态地球化学循环中起着非常重要的作用。此外，在这项研究中确定的TBDR和CUT基因座是明显不同的特征在于在人类肠道共生体多形拟杆菌，这使得聚糖觅食，表明在变形菌和拟杆菌的TBDR的趋同进化。
TonB-dependent receptors (TBDRs) are outer membrane proteins mainly known for the active transport of iron siderophore complexes in Gram-negative bacteria. Analysis of the genome of the phytopathogenic bacterium Xanthomonas campestris pv. campestris (Xcc), predicts 72 TBDRs. Such an overrepresentation is common in Xanthomonas species but is limited to only a small number of bacteria. Here, we show that one Xcc TBDR transports sucrose with a very high affinity, suggesting that it might be a sucrose scavenger. This TBDR acts with an inner membrane transporter, an amylosucrase and a regulator to utilize sucrose, thus defining a new type of carbohydrate utilization locus, named CUT locus, involving a TBDR for the transport of substrate across the outer membrane. This sucrose CUT locus is required for full pathogenicity on Arabidopsis, showing its importance for the adaptation to host plants. A systematic analysis of Xcc TBDR genes and a genome context survey suggested that several Xcc TBDRs belong to other CUT loci involved in the utilization of various plant carbohydrates. Interestingly, several Xcc TBDRs and CUT loci are conserved in aquatic bacteria such as Caulobacter crescentus, Colwellia psychrerythraea, Saccharophagus degradans, Shewanella spp., Sphingomonas spp. or Pseudoalteromonas spp., which share the ability to degrade a wide variety of complex carbohydrates and display TBDR overrepresentation. We therefore propose that TBDR overrepresentation and the presence of CUT loci designate the ability to scavenge carbohydrates. Thus CUT loci, which seem to participate to the adaptation of phytopathogenic bacteria to their host plants, might also play a very important role in the biogeochemical cycling of plant-derived nutrients in marine environments. Moreover, the TBDRs and CUT loci identified in this study are clearly different from those characterized in the human gut symbiont Bacteroides thetaiotaomicron, which allow glycan foraging, suggesting a convergent evolution of TBDRs in Proteobacteria and Bacteroidetes.
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影响因子：
3.2
作者：
Bogs, J;Geider, K
通讯作者：
Geider, K
DOI：
10.1073/pnas.0509393103
发表时间：
2006-09-26
影响因子：
11.1
作者：
Angot, Aurelie;Peeters, Nemo;Genin, Stephane
通讯作者：
Genin, Stephane
影响因子：
3.6
作者：
Brown, JS;Gilliland, SM;Holden, DW
通讯作者：
Holden, DW
影响因子：
5.1
作者：
Bauer, Margarete;Kube, Michael;Gloeckner, Frank Oliver
通讯作者：
Gloeckner, Frank Oliver
影响因子：
14.9
作者：
CORPET, F
通讯作者：
CORPET, F