More than 3,000 isolates of fluorescent pseudomonads have been collected from plant roots in Japan and screened for the presence of antibiotic-synthesizing genes. In total, 927 hydrogen cyanide (HCN)-, 47 2,4-diacetylphloroglucinol (PHL)-, 6 pyoluteorin (PLT)-, 14 pyrrolnitrin (PRN)-, and 8 phenazine (PHZ)-producing isolates have been detected. A cluster analysis (≥99% identity) identified 10 operational taxonomic units (OTUs) in antibiotic biosynthesis gene-possessing pseudomonads. OTU HLR (PHL, PLT, and PRN) contained four antibiotics: HCN, PHL, PLT, and PRN, while OTU RZ (PRN and PHZ) contained three: HCN, PRN, and PHZ. OTU H1, H2, H3, H4, H5, H6, and H7 (PHL1-7) contained two antibiotics: HCN and PHL, while OTU H8 (PHL8) contained one: PHL. Isolates belonging to OTU HLR and RZ suppressed damping-off disease in cabbage seedlings caused by Rhizoctonia solani. Effective strains belonging to OTU HLR and RZ were related to Pseudomonas protegens and Pseudomonas chlororaphis, respectively. Antibiotic biosynthesis gene-possessing fluorescent pseudomonads are distributed among different geographical sites in Japan and plant species.

中文翻译：

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日本具有根际荧光假单胞菌的抗生素生物合成基因多样性及其生防功效

从日本的植物根部收集了 3,000 多个荧光假单胞菌分离株，并筛选了抗生素合成基因的存在。总共检测到 927 种氰化氢 (HCN)-、47 种 2,4-二乙酰间苯三酚 (PHL)-、6 绿脓杆菌 (PLT)-、14 吡咯尼群 (PRN)-和 8 种吩嗪 (PHZ) 分离株。聚类分析（≥99% 同一性）在抗生素生物合成基因的假单胞菌中鉴定了 10 个操作分类单元 (OTU)。OTU HLR（PHL、PLT 和 PRN）包含四种抗生素：HCN、PHL、PLT 和 PRN，而 OTU RZ（PRN 和 PHZ）包含三种：HCN、PRN 和 PHZ。OTU H1、H2、H3、H4、H5、H6和H7（PHL1-7）含有两种抗生素：HCN和PHL，而OTU H8（PHL8）含有一种：PHL。属于 OTU HLR 和 RZ 的分离株抑制了由立枯丝核菌引起的甘蓝幼苗猝倒病。属于 OTU HLR 和 RZ 的有效菌株分别与 Pseudomonas protegens 和 Pseudomonas chlororaphis 相关。具有抗生素生物合成基因的荧光假单胞菌分布在日本的不同地理位点和植物物种中。