Characterization of phenazine-1-carboxylic acid by Klebsiella sp. NP-C49 from the coral environment in Gulf of Kutch, India

Abstract

Coral-associated microbes from Marine National Park (MNP), Gulf of Kutch (GoK), Gujarat, India, were screened for siderophore production. Maximum siderophore-producing isolate NP-C49 and its compound were identified and characterized. The isolate was identified as Klebsiella sp. through 16S rRNA genes sequencing (GenBank accession nos. KY412519 and MTCC 25160). Antibiotic susceptibility profile against 20 commercial antibiotics showed its more sensitivity compared to human pathogenic strain, i.e., Klebsiella pneumonia. The compound was identified as phenazine-1-carboxylic acid (PCA) using the multinuclear ID ( 1 H and 13 C) and 2D ( 1 H-1 H COSY and 1 H-13 C HETCOR) NMR along with high-resolution mass spectrometry. No significant difference in the bacterial growth in the presence of PCA, FeCl 3 and Fe(OH) 3 indicated involvement of factors other than PCA in bacterial growth. The study first reports the identification and characterization of PCA from Klebsiella sp. both from terrestrial and marine sources. Keywords Coral environment • phenazine-1-carboxylic acid • Klebsiella sp. • Gulf of Kutch Communicated by Erko Stackebrandt. Neha P. Patel and M. Raju contributed equally to the manuscript.

Straw Mulching and Nitrogen Fertilization Affect Diazotroph Communities in Wheat Rhizosphere

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Soil bacteria protect fungi from phenazines by acting as toxin sponges

“…7,8 Paradoxically, many fungi that are sensitive to phenazines are routinely found living in close proximity to phenazine-producing bacteria, including pathogenic fungi in the lungs of cystic fibrosis patients and beneficial and phytopathogenic fungi in the rhizosphere and in oceanic environments, including coral. [9][10][11][12] This pattern of co-habitation indicates there may be a general way fungi are screened for membership in microbial communities that produce phenazines that holds broad relevance. We set out to identify such a putative screening mechanism, a necessary step toward the goal of manipulating these microbial communities for human benefit.…”

Paraburkholderia edwiniiprotectsAspergillussp. from phenazines by acting as a toxin sponge

“…Given that drier soils are also associated with higher rates of phenazine producers colonizing wheat, this suggests that soil fungi may need to contend with higher concentrations of phenazines as the climate shifts 7,8 . Paradoxically, many fungi that are sensitive to phenazines are routinely found living in close proximity to phenazine-producing bacteria, including pathogenic fungi in the lungs of cystic fibrosis patients, beneficial and phytopathogenic fungi in the rhizosphere, and in oceanic environments including coral [9][10][11][12] . This pattern of co-habitation indicates there may be a general way fungi are screened for membership in microbial communities that produce phenazines that holds broad relevance.…”