Thaxtomin A is a diketopiperazine phytotoxin produced by plant pathogenic bacteria such as Streptomyces scabies[1-2]. Thaxtomin A disrupts cell wall integrity by inhibiting plant cellulose biosynthesis and induces programmed cell death (PCD) in plant cells. Thaxtomin A can be used in research related to the pathogenic mechanisms of Streptomyces scabiesand the development of novel natural herbicides[3-4].
In vitro, A. thaliana cells were treated with Thaxtomin A (10μM) for 6 hours. Thaxtomin A induced an early, transient Ca²⁺ influx. N. tabacum BY2 cells were treated with Thaxtomin A (20μM) for 6 hours, which did not cause an increase in cytoplasmic Ca²⁺ concentration[5]. A. thaliana cells were treated with Thaxtomin A (2.0–10.0μM) for 24–72 hours. Thaxtomin A caused DNA fragmentation in the nucleus and induced programmed cell death (PCD)[6].
References:
[1] Clarke CR, Kramer CG, Kotha RR, et al. The Phytotoxin Thaxtomin A Is the Primary Virulence Determinant for Scab Disease of Beet, Carrot, and Radish Caused by Streptomyces scabiei. Phytopathology. 2022 Nov;112(11):2288-2295.
[2] Li Y, Liu J, Adekunle D, et al. TxtH is a key component of the thaxtomin biosynthetic machinery in the potato common scab pathogen Streptomyces scabies. Mol Plant Pathol. 2019 Oct;20(10):1379-1393.
[3] Casey C, Köcher T, Champion C, et al. Reduced coenzyme Q synthesis confers non-target site resistance to the herbicide thaxtomin A. PLoS Genet. 2023 Jan 6;19(1):e1010423.
[4] Zhang H, Wang Q, Ning X, et al. Synthesis and biological evaluations of a series of thaxtomin analogues. J Agric Food Chem. 2015 Apr 15;63(14):3734-41.
[5] Meimoun P, Tran D, Baz M, et al. Two different signaling pathways for thaxtomin A-induced cell death in Arabidopsis and tobacco BY2. Plant Signal Behav. 2009 Feb;4(2):142-4.
[6] Duval I, Brochu V, Simard M, et al. Thaxtomin A induces programmed cell death in Arabidopsis thaliana suspension-cultured cells. Planta. 2005 Nov;222(5):820-31.
Thaxtomin A是一种由Streptomyces scabies等植物病原菌产生的二酮哌嗪类植物毒素[1-2]。Thaxtomin A可通过抑制植物纤维素合成来破坏细胞壁完整性，同时通过诱导植物细胞程序性死亡。Thaxtomin A可用于Streptomyces scabies致病机理和新型天然除草剂开发的相关研究[3-4]。
在体外，Thaxtomin A（10μM）处理A. thaliana细胞6小时，可诱导一个早期、短暂的Ca²⁺内流。Thaxtomin A（20μM）处理N. tabacum BY2细胞6小时，不会引起胞质Ca²⁺浓的增加[5]。Thaxtomin A（2.0–10.0μM）处理A. thaliana细胞24–72h。Thaxtomin A引起了细胞核DNA片段化，诱导了程序性细胞死亡（PCD）[6]。