内生青霉GS218的基因组分析及对辣椒炭疽的拮抗特性

Endophytic Penicillium GS218: whole genome analysis and characterization of antagonism against Colletotrichum gloeosporioides in pepper

摘要:

目的 探究内生真菌青霉属新种中华青霉(Penicillium sinense) GS218的生防潜力，解析其抑菌机制，为辣椒炭疽病的生物防治提供优良菌种资源及理论基础。方法 采用平板检测法测定GS218的水解酶活性与产铁载体能力；通过平板对峙法评估GS218对不同植物病原真菌的抑制效果；对菌株进行全基因组测序，深入了解其遗传信息与生理功能；分析菌株GS218与辣椒炭疽病原菌共培养状态下的代谢组学，挖掘潜在抑菌活性物质，并利用含药平板法验证部分代谢物的抑菌活性。结果 菌株GS218具有水解酶活性，可产生铁载体，对5种病原真菌表现出较强抑制效果，其中对辣椒炭疽病原菌的抑制率达72.76%，GS218无菌发酵滤液对辣椒炭疽病具有良好的防治效果。全基因组分析显示，菌株GS218的基因组大小为27.77 Mb，具有丰富的代谢途径，其基因组中含有30个次级代谢产物基因簇。代谢组分析表明，菌株GS218在有机酸及其衍生物、苯丙素和聚酮、脂质和类脂分子(包括萜类)三大类化合物中含有较多潜在抑菌活性代谢物，7-乙氧基香豆素、丙酮酸等化合物对辣椒炭疽病原菌表现出一定抑制作用。结论 新种中华青霉GS218对辣椒炭疽病原菌具有显著抑制作用，在农业绿色发展中具有良好的应用潜力，全基因组测序和代谢组学分析为进一步深入研究菌株GS218的生防机制提供了理论依据。

Abstract:

Objective To investigate the biocontrol potential of Penicillium sinense GS218, a new endophytic fungus, and to analyze the antifungal mechanism, so as to provide elite strain resources and lay a theoretical foundation for the biocontrol of Colletotrichum gloeosporioides in pepper.Methods Plate assays were employed to determine the hydrolase activity and siderophore production capacity of GS218. The inhibitory effects of GS218 on different phytopathogenic fungi were evaluated by the plate confrontation method. Whole genome sequencing was performed to obtain insights into the genetic information and physiological functions of the strain. The metabolome of strain GS218 co-cultured with C. gloeosporioides was analyzed to explore the potential active substances for the inhibitory effects. The medicated plate method was employed to validate the inhibitory activities of differential metabolites.Results Strain GS218 had hydrolase activity, produced siderophores, and exhibited strong inhibitory effects on five pathogenic fungi (with the inhibition rate of 72.76% on C. gloeosporioides in pepper). The sterile fermentation filtrate of strain GS218 demonstrated a good control effect on pepper anthracnose. The genome size of strain GS218 was 27.77 Mb, which has abundant metabolic pathways, and its genome contained 30 synthetic gene clusters for secondary metabolites. The metabolomics analysis showed that strain GS218 contained rich antimicrobial substances in organic acids and derivatives, phenylpropanoids and polyketides, and lipids and lipid-like molecules (including terpenoids). Compounds such as 7-ethoxycoumarin and pyruvic acid showed inhibitory effects against C. gloeosporioides in pepper.Conclusion The new strain, P. sinense GS218, has significant inhibitory effects on C. gloeosporioides and promising application prospects in the green development of agriculture. Whole genome sequencing and metabolomics analysis provide a theoretical basis for deciphering the biocontrol mechanism of strain GS218.