高产IAA抗旱菌株SZF7的培养条件优化及功能基因挖掘  

Optimization of Culture Conditions and Functional Gene Mining of High-yielding IAA Drought-resistant Strain SZF7

作　　者：林宏 黄玉莲 黄卫红 李若雨 薛喜枚 张英娇 张秋芳 LIN Hong;HUANG Yulian;HUANG Weihong;LI Ruoyu;XUE Ximei;ZHANG Yingjiao;ZHANG Qiufang(College of Oceanography and Food,Quanzhou Normal University,Quanzhou,Fujian 362000,China;Institute of Urban Environment,Chinese Academy of Sciences,Xiamen,Fujian 361021,China;College of Geography and Oceanography,Minjiang University,Fuzhou,Fujian 350108,China)

机构地区：[1]泉州师范学院海洋与食品学院,福建泉州362000 [2]中国科学院城市环境研究所,福建厦门361021 [3]闽江学院地理与海洋学院,福建福州350108

出　　处：《热带作物学报》2025年第3期734-742,共9页Chinese Journal of Tropical Crops

基　　金：福建省科技厅引导性项目(No.2020N0032,No.2022N0026);国家重点研发计划项目(No.2023YFD1701703)。

摘　　要：作为一种非生物胁迫,干旱导致经济作物产量和质量下降,从而严重影响其经济效益,因此,一些能够替代化学抗旱制剂且对植物具有促生作用的功能微生物亟待发掘。本研究以武夷山茶园土壤细菌为研究对象,筛选获得高分泌吲哚乙酸(indole-3-aceticacid,IAA)能力的强抗旱菌株,并对其进行最佳培养条件优化和全基因组测序分析。结果表明:获得1株具有高分泌IAA能力的强抗旱菌株SZF7,其抗旱能力强于其他同批次筛选的菌株,经鉴定SZF7为蜡状芽孢杆菌(Bacilluscereus);SZF7分泌IAA的最佳培养条件为pH5.0、温度37℃和培养时间24h,且pH和温度对其IAA分泌量具有显著影响;SZF7基因组的COG和KEGG代谢途径中,参与生物代谢大类的基因数量分别占总功能基因的47.96%和68.52%,且其基因组包含IAA、铁载体、非核糖体肽合成酶(nonribosomal peptide synthetase,NRPS)、脂肽类化合物和嗜铁素等植物促生相关基因;SZF7的IAA合成途径分别为由吲哚-3-丙酮酸脱羧酶催化的吲哚-3-丙酮酸途径和吲哚-3-甘油磷酸合成酶催化的色胺酸途径。本研究结果为抗旱促生菌剂在茶叶等经济作物生产上的应用提供科学依据。Drought resistant microbial preparations are beneficial soil microorganisms that produce plant growth hor-mone to enhance the drought tolerance of plants and promote plant growth,which is an ideal substitute for traditional chemical drought resistant preparations.In this study,the bacteria obtained in the soils of Wuyishan tea plantation were used as the research object to screen strains with the high secretion indole-3-acetic acid(IAA)ability and strong drought resistance,and the culture conditions optimization and whole genome sequencing analysis were also conducted.A strain SZF7 with high secreting IAA was obtained,which belonged to Bacillus cereus,which had stronger drought resistance than other strains.The optimal culture conditions for IAA secretion of SZF7 were pH 5.0 and 37℃with 24 h incuba-tion,and pH and temperature significantly affected on the IAA secretion.In the COG and KEGG metabolic pathways of SZF7 genome,the genes related to biological metabolism accounted for 47.96%and 68.52%of the total functional genes,respectively.The genes related to plant growth promotion included IAA,siderophore,non-ribosomal peptide synthase(NRPS),lipopeptide compounds and bacillibactin.There were two IAA synthesis pathways in SZF7,one of which was indole-3-pyruvate pathway mediated by indole-3-pyruvate decarboxylase,and the other was tryptamine pathway mediated by indole-3-glycerol phosphate synthase.This study would provide a scientific basis for the applica-tion of drought-resistant and growth-promoting bacteria in the production of tea and other cash crops.

关 键 词：促生菌 吲哚乙酸 抗旱 培养条件优化 全基因组分析 

分 类 号：S154.39[农业科学—土壤学]