In this study, nine strains of Pseudomonas aurantiaca and P. chlororaphis, and two isolates of Pseudomonas sp.: At1RP4 and RS-1, were characterized for the in-vitro production of secondary metabolites in LB, DMB, and King’s B media, and of the genes responsible for the production of antagonistic metabolites. Based on 16S rRNA gene sequence, isolates At1RP4 and RS-1 were identified as strains of P. aeruginosa and P. fluorescens. Five phenazine derivatives comprising phenazine, phenazine-1-carboxylic acid (PCA), 2-hydroxyphenazine-1-carboxylic acid (2-OH-Phz-1-COOH), phenazine-1,6-dicarboxylic acid (Phz-1,6-di-COOH), and 2-hydroxyphenazine (2-OH-Phz) were produced by all strains in all three culture media including DMB, King’s B and LB. However, 2,8-dihydroxyphenazine, 6-methylphenazine-1-carboxylic acid, pyrrolnitrin, and the ortho-dialkyl-aromatic acids, were produced by the P. aurantiaca and P. chlororaphis strains. In addition, all strains produced 2-acetamidophenol, pyochelin, and diketopiperazine derivatives in variable amounts in all three culture media used. Highest levels of quorum-sensing signal molecules including PQS, 2-Octyl-3-hydroxy-4(1H)-quinolone, and hexahydro-quinoxaline-1,4-dioxide were recorded for P. aeruginosa At1RP4. Moreover, all strains produced volatile hydrogen cyanide (0.95–6.68 µg/L) and the phytohormone indole-3-acetic acid (0.42–13.9 µM). Production of extracellular lipase and protease was recorded in all pseudomonads, whereas, cellulase production and phosphate solubilization were variable. Genes for hydrogen cyanide and phenazine-1-carboxylic acid were detected in all eleven strains while the gene for pyrrolnitrin biosynthesis was amplified in P. aurantiaca and P. chlororaphis strains. Comparative metabolomic analysis provided detailed insights about the strain-specific metabolites in pseudomonads, and their pseudo-relative quantification in different bacterial growth media to be used as single-strain biofertilizer and biocontrol inoculums.

在这项研究中，有 9 株Pseudomonas au rantiaca和P. chlororaphis以及 2 个Pseudomonas sp的分离株。：At1RP4 和 RS-1 的特征在于体外产生 LB、DMB 和 King's B 培养基中的次级代谢物，以及负责产生拮抗代谢物的基因。根据 16S rRNA 基因序列，分离株 At1RP4 和 RS-1 被鉴定为铜绿假单胞菌和荧光假单胞菌菌株. 五种吩嗪衍生物，包括吩嗪、吩嗪-1-羧酸 (PCA)、2-羟基吩嗪-1-羧酸 (2-OH-Phz-1-COOH)、吩嗪-1,6-二羧酸 (Phz-1,6 -di-COOH) 和 2-羟基吩嗪 (2-OH-Phz) 由所有三种培养基（包括 DMB、King's B 和 LB）中的所有菌株产生。然而，2,8-二羟基吩嗪、6-甲基吩嗪-1-羧酸、吡咯尼群和邻-二烷基-芳族酸是由P. aurantiaca和P. chlororaphis 生产的菌株。此外，所有菌株在使用的所有三种培养基中都产生了不同数量的 2-乙酰氨基苯酚、绿脓杆菌素和二酮哌嗪衍生物。铜绿假单胞菌At1RP4记录了最高水平的群体感应信号分子，包括 PQS、2-Octyl-3-hydroxy-4(1H)-quinolone 和 hexahydro-quinoxaline-1,4-dioxide 。此外，所有菌株均产生挥发性氰化氢 (0.95–6.68 µg/L) 和植物激素吲哚-3-乙酸 (0.42–13.9 µM)。在所有假单胞菌中都记录了细胞外脂肪酶和蛋白酶的产生，而纤维素酶的产生和磷酸盐溶解是可变的。在所有 11 株菌株中检测到氰化氢和吩嗪-1-羧酸基因，而在P. aurantiaca中扩增了吡咯尼群生物合成基因和P. chlororaphis菌株。比较代谢组学分析提供了有关假单胞菌中菌株特异性代谢物的详细见解，以及它们在不同细菌生长培养基中用作单菌株生物肥料和生物防治接种物的伪相对定量。