Department of Biochemistry, University of Calcutta, 35, Ballygunge Circular Road, Kolkata, West Bengal, 700019, India.
Sister Nibedita Government General Degree College for Girls, Hastings House, 20B, Judges Court Road, Kolkata, West Bengal, 700027, India.
Arch Microbiol. 2021 Dec 23;204(1):62. doi: 10.1007/s00203-021-02631-w.
Macrophomina phaseolina, a necrotrophic fungal pathogen is known to cause charcoal rot disease in food crops, pulse crops, oil crops and cotton and fibre crops. Necrotrophic fungi survive on dead plant tissue. It is well known that reactive oxygen species (ROS) are produced by the host plant during plant-pathogen interaction. However, it is still unclear how M. phaseolina can overcome the ROS-induced cellular damage. To mimic the invasion of M. phaseolina inside the plant cell wall, we developed solid substrate fermentation where M. phaseolina spore suspension was inoculated on a wheat bran bed and incubated for vegetative growth. To analyse the secretome of M. phaseolina after different day interval, its secretory material was collected and concentrated. Both superoxide dismutase (SOD) and catalase were detected in the secretome by zymogram. The presence of SOD and catalase was further confirmed by liquid chromatography based mass spectrometry. The physicochemical properties of M. phaseolina catalase in terms of stability towards pH, temperature, metal ions and chaotropic agent and inhibitors indicated its fitness at different environmental conditions. Apart from the production of catalase in SSF, the studies on this particular microorganism may also have significance in necrotrophic fungal pathogen and their susceptible host plant interaction.
尖孢镰刀菌是一种专性坏死型真菌病原体，已知可导致粮食作物、豆科作物、油料作物和棉花及纤维作物的炭腐病。坏死型真菌依靠死亡的植物组织存活。众所周知，在植物-病原体相互作用过程中，寄主植物会产生活性氧（ROS）。然而，目前尚不清楚尖孢镰刀菌如何能够克服 ROS 诱导的细胞损伤。为了模拟尖孢镰刀菌在植物细胞壁内的入侵，我们开发了固体基质发酵技术，将尖孢镰刀菌孢子悬浮液接种在麦麸床上进行营养生长。为了分析不同时间间隔后尖孢镰刀菌的分泌组，收集并浓缩其分泌物质。通过同工酶法在分泌组中检测到超氧化物歧化酶（SOD）和过氧化氢酶。通过基于液相色谱的质谱进一步证实了 SOD 和过氧化氢酶的存在。尖孢镰刀菌过氧化氢酶的物理化学性质（包括对 pH 值、温度、金属离子和变性剂的稳定性以及抑制剂）表明其在不同环境条件下的适应性。除了在 SSF 中产生过氧化氢酶外，对这种特定微生物的研究对于坏死型真菌病原体及其易感宿主植物的相互作用也可能具有重要意义。
