title: Functional characterization of a novel hydrocarbonoclastic Pseudomonas sp. strain PUP6 with plant-growth-promoting traits and antifungal potential.
abstract: A novel hydrocarbonoclastic bacterium was isolated from rice rhizospheric soil using an enrichment culture technique. Detailed taxonomic studies identified the organism, designated strain PUP6, as a member of the genus Pseudomonas. The bacterium grew in minimal medium amended with n-alkane members of hydrocarbons, n-dodecane (C12H26), n-hexadecane (C16H34), n-octadecane (C18H38), n-octacosane (C28H58); and petroleum fractions such as crude oil and lubricating oil when provided as sole carbon and energy source. Degradation of these n-alkane hydrocarbons and oils in minimal salts medium by strain PUP6 was estimated using gas chromatography with a flame ionization detector. In addition to its hydrocarbonoclastic properties, this bacterium exhibits a broad spectrum of fungal antibiosis against various phytopathogenic fungi. An antifungal metabolite produced by strain PUP6 was isolated, characterized and identified as phenazine-1-carboxamide on the basis of nuclear magnetic resonance and mass spectroscopic analyses. Strain PUP6 also produced plant-growth-promoting siderophores, indoleacetic acid (IAA), phosphate solubilizing enzymes, and fungal cell wall degrading enzymes such as protease and chitinase. This study can be considered as the first report on n-alkane hydrocarbon and oil degradation by a rhizosphere soil bacterium that exhibits biofertilizing and biocontrol traits. Due to its innate multiple functional traits beyond its role in degradation of hydrocarbons, strain PUP6 may be used as plant-growth-promoting rhizobacterium and biocontrol agent against phytopathogenic fungi.
authors.affiliation: Department of Biotechnology, Pondicherry University, Kalapet, Pondicherry 605014, India.
authors.forename: Popavath Ravindra
authors.initials: PR
authors.lastname: Naik
authors.forename: Natarajan
authors.initials: N
authors.lastname: Sakthivel
mesh_terms: D000473:Alkanes / Q000378:metabolism*; D002473:Cell Wall / Q000378:metabolism; D002480:Cellulase / Q000378:metabolism; D002688:Chitinases / Q000096:biosynthesis / Q000494:pharmacology; D005658:Fungi / Q000201:enzymology / Q000254:growth & development*; D007210:Indoleacetic Acids / Q000378:metabolism; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D009821:Oils / Q000378:metabolism*; D012275:Oryza / Q000382:microbiology; D010619:Phenazines / Q000737:chemistry / Q000378:metabolism; D063245:Plant Development; D010937:Plant Growth Regulators / Q000378:metabolism; D010944:Plants / Q000382:microbiology; D011096:Polygalacturonase / Q000378:metabolism; D011549:Pseudomonas / Q000302:isolation & purification / Q000378:metabolism / Q000502:physiology*; D012988:Soil Microbiology
chemical_list: D000473:Alkanes; D007210:Indoleacetic Acids; D009821:Oils; D010619:Phenazines; D010937:Plant Growth Regulators; C420923:phenazine-1-carboxamide; D002688:Chitinases; D011096:Polygalacturonase; D002480:Cellulase