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Isolation and Antibacterial Activity of Indole Alkaloids from Pseudomonas aeruginosa UWI-1.

ABSTRACT: In this study, we report the first isolation of three antibiotic indole alkaloid compounds from a Pseudomonad bacterium, Pseudomonas aeruginosa UWI-1. The bacterium was batch fermented in a modified Luria Broth medium and compounds were solvent extracted and isolated by bioassay-guided fractionation. The three compounds were identified as (1) tris(1H-indol-3-yl) methylium, (2) bis(indol-3-yl) phenylmethane, and (3) indolo (2, 1b) quinazoline-6, 12 dione. A combination of 1D and 2D NMR, high-resolution mass spectrometry data and comparison from related data from the literature was used to determine the chemical structures of the compounds. Compounds 1-3 were evaluated in vitro for their antimicrobial activities against a wide range of microorganisms using the broth microdilution technique. Compounds 1 and 2 displayed antibacterial activity against only Gram-positive pathogens, although 1 had significantly lower minimum inhibitory concentration (MIC) values than 2. Compound 3 displayed potent broad-spectrum antimicrobial activity against a range of Gram positive and negative bacteria. Several genes identified from the genome of P. aeruginosa UWI-1 were postulated to contribute to the biosynthesis of these compounds and we attempted to outline a possible route for bacterial synthesis. This study demonstrated the extended metabolic capability of Pseudomonas aeruginosa in synthesizing new chemotypes of bioactive compounds.

SUBMITTER: Ramkissoon A

PROVIDER: S-EPMC7464872 | biostudies-literature | 2020 Aug

REPOSITORIES: biostudies-literature

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Isolation and Antibacterial Activity of Indole Alkaloids from Pseudomonas aeruginosa UWI-1.

Ramkissoon Antonio A Seepersaud Mohindra M Maxwell Anderson A Jayaraman Jayaraj J Ramsubhag Adesh A

Molecules (Basel, Switzerland) 20200817 16

In this study, we report the first isolation of three antibiotic indole alkaloid compounds from a Pseudomonad bacterium, Pseudomonas aeruginosa UWI-1. The bacterium was batch fermented in a modified Luria Broth medium and compounds were solvent extracted and isolated by bioassay-guided fractionation. The three compounds were identified as (1) tris(1H-indol-3-yl) methylium, (2) bis(indol-3-yl) phenylmethane, and (3) indolo (2, 1b) quinazoline-6, 12 dione. A combination ...[more]

PMID: 32824432

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Isolation and Antibacterial Activity of Indole Alkaloids from Pseudomonas aeruginosa UWI-1.

Publications

Isolation and Antibacterial Activity of Indole Alkaloids from <i>Pseudomonas aeruginosa</i> UWI-1.

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