Bio-Protection Research Centre, Institute of Molecular BioSciences, Massey University, Palmerston North, New Zealand.
Toxins (Basel). 2010 Dec;2(12):2738-53. doi: 10.3390/toxins2122738. Epub 2010 Nov 29.
The peanut leaf spot pathogen Passalora arachidicola (Mycosphaerella arachidis) is known to produce dothistromin, a mycotoxin related to aflatoxin. This is a feature shared with the pine needle pathogen Dothistroma septosporum (Mycosphaerella pini). Dothistromin biosynthesis in D. septosporum commences at an unusually early stage of growth in culture compared to most other fungal secondary metabolites, and the biosynthetic genes are arranged in fragmented groups, in contrast to aflatoxin gene clusters. Dothistromin biosynthetic genes were identified and studied in P. arachidicola to determine if the attributes described in D. septosporum are shared by another dothistromin-producing species within the Class Dothideomycetes. It was shown that dothistromin biosynthesis is very similar in the two species with regard to gene sequence and gene synteny. Functional complementation of D. septosporum mutants with P. arachidicola dothistromin genes was also possible. These similarities support a vertical mode of dothistromin gene transmission. P. arachidicola also produced dothistromin at an early growth stage in culture, suggesting that this type of regulation pattern may be relevant to the biological role of dothistromin.
花生叶斑病病原菌 Passalora arachidicola（Mycosphaerella arachidis）已知会产生与黄曲霉毒素有关的真菌毒素多曲霉素。这一特征与松针病原菌长喙壳菌（Dothistroma septosporum）（Mycosphaerella pini）共享。与大多数其他真菌次生代谢物相比，多曲霉素在 D. septosporum 的培养物中生长的异常早期阶段开始生物合成，并且生物合成基因以碎片化的群体排列，而不是黄曲霉毒素基因簇。鉴定并研究了 P. arachidicola 中的多曲霉素生物合成基因，以确定在其他 Class Dothideomycetes 产多曲霉素的物种中是否具有 D. septosporum 中描述的特征。结果表明，在基因序列和基因同线性方面，两种物种的多曲霉素生物合成非常相似。还可以通过功能互补的方式将 D. septosporum 突变体与 P. arachidicola 多曲霉素基因进行互补。这些相似性支持了多曲霉素基因垂直传递的模式。在培养物中，P. arachidicola 也在早期生长阶段产生多曲霉素，这表明这种调控模式可能与多曲霉素的生物学作用有关。
