Function and Regulation of Agrobacterium tumefaciens Cell Surface Structures that Promote Attachment.
Function and Regulation of Agrobacterium tumefaciens Cell Surface Structures that Promote Attachment.
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DOI：
10.1007/82_2018_96
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发表时间：
2018
影响因子：
--
通讯作者：
Fuqua C
中科院分区：
文献类型：
--
作者：
Thompson MA;Onyeziri MC;Fuqua C
根癌农杆菌稳定附着在植物宿主组织和非生物表面。在发病过程中，与感染部位的物理附着是感染和水平基因转移到植物的先决条件。有毒和无毒菌株也可能附着在更良性的植物群落中的植物组织上，并且与其他土壤微生物一样，附着在陆地环境中的土壤表面。尽管大多数根癌农杆菌毒力功能是在肿瘤诱导质粒上编码的，但指导一般表面附着的基因是由染色体编码的，因此该过程并不一定与毒力相关，而是一种更基本的能力。已知或怀疑几种不同的细胞结构有助于附着过程。鞭毛主要通过其推进活动影响表面附着，但在过渡到附着状态期间对其旋转的控制可能相当复杂。根癌农杆菌产生多种菌毛，包括 Tad 型 Ctp 菌毛，以及由 Ti 和 At 质粒编码的几种质粒携带的接合菌毛，以及参与界间水平基因转移的所谓 T 菌毛。 Ctp 菌毛促进与表面的可逆相互作用，而接合菌毛和 T-菌毛则驱动与其他细胞和组织的水平基因转移 (HGT) 相互作用。在 DNA 转移到植物过程中，T 菌毛可能有助于与植物组织的物理联系。根癌农杆菌可以合成多种多糖，包括纤维素、凝乳多糖（β−1,3 葡聚糖）、β−1,2 葡聚糖（环状和直链）、琥珀酸聚糖和局限于单个细胞极的局部多糖，称为单极多糖 (UPP)。脂多糖也存在于外膜的外层小叶中。在某些条件下，纤维素和凝胶多糖的产生会影响附着。 UPP 需要在各种条件下以及非生物和生物表面上稳定附着。据报道，其他在附着中发挥作用的因素包括难以捉摸的蛋白质，称为根粘附素。表面附着过程受到广泛的监管控制，并且可以通过环境条件以及对表面接触的直接反应来调节。复杂的转录和转录后控制电路是这些附着功能的产生和部署的基础。
Agrobacterium tumefaciens attaches stably to plant host tissues and abiotic surfaces. During pathogenesis, physical attachment to the site of infection is a prerequisite to infection and horizontal gene transfer to the plant. Virulent and avirulent strains may also attach to plant tissue in more benign plant associations, and as with other soil microbes, to soil surfaces in the terrestrial environment. Although most A. tumefaciens virulence functions are encoded on the tumor-inducing plasmid, genes that direct general surface attachment are chromosomally encoded, and thus this process is not obligatorily tied to virulence, but is a more fundamental capacity. Several different cellular structures are known or suspected to contribute to the attachment process. The flagella influence surface attachment primarily via their propulsive activity, but control of their rotation during the transition to the attached state may be quite complex. A. tumefaciens produces several pili, including the Tad-type Ctp pili, and several plasmid-borne conjugal pili encoded by the Ti and At plasmids, as well as the so-called T-pilus, involved in interkingdom horizontal gene transfer. The Ctp pili promote reversible interactions with surfaces, whereas the conjugal and T-pili drive horizontal gene transfer (HGT) interactions with other cells and tissues. The T-pilus is likely to contribute to physical association with plant tissues during DNA transfer to plants. A. tumefaciens can synthesize a variety of polysaccharides including cellulose, curdlan (β−1,3 glucan), β−1,2 glucan (cyclic and linear), succinoglycan, and a localized polysaccharide(s) that is confined to a single cellular pole and is called the unipolar polysaccharide (UPP). Lipopolysaccharides are also in the outer leaflet of the outer membrane. Cellulose and curdlan production can influence attachment under certain conditions. The UPP is required for stable attachment under a range of conditions and on abiotic and biotic surfaces. Other factors that have been reported to play a role in attachment include the elusive protein called rhicadhesin. The process of surface attachment is under extensive regulatory control, and can be modulated by environmental conditions, as well as by direct responses to surface contact. Complex transcriptional and post-transcriptional control circuitry underlies much of the production and deployment of these attachment functions.
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影响因子：
64.5
作者：
Costa TRD;Ilangovan A;Ukleja M;Redzej A;Santini JM;Smith TK;Egelman EH;Waksman G
通讯作者：
Waksman G
影响因子：
3.2
作者：
Bodenmiller, D;Toh, E;Brun, YV
通讯作者：
Brun, YV
影响因子：
3.2
作者：
Chen, LS;Chen, YC;Nester, EW
通讯作者：
Nester, EW
影响因子：
3.7
作者：
Berne C;Ducret A;Hardy GG;Brun YV
通讯作者：
Brun YV
影响因子：
3.2
作者：
AMIKAM, D;BENZIMAN, M
通讯作者：
BENZIMAN, M