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Streptomyces thermoautotrophicus does not fix nitrogen.

ABSTRACT: Streptomyces thermoautotrophicus UBT1 has been described as a moderately thermophilic chemolithoautotroph with a novel nitrogenase enzyme that is oxygen-insensitive. We have cultured the UBT1 strain, and have isolated two new strains (H1 and P1-2) of very similar phenotypic and genetic characters. These strains show minimal growth on ammonium-free media, and fail to incorporate isotopically labeled N2 gas into biomass in multiple independent assays. The sdn genes previously published as the putative nitrogenase of S. thermoautotrophicus have little similarity to anything found in draft genome sequences, published here, for strains H1 and UBT1, but share >99% nucleotide identity with genes from Hydrogenibacillus schlegelii, a draft genome for which is also presented here. H. schlegelii similarly lacks nitrogenase genes and is a non-diazotroph. We propose reclassification of the species containing strains UBT1, H1, and P1-2 as a non-Streptomycete, non-diazotrophic, facultative chemolithoautotroph and conclude that the existence of the previously proposed oxygen-tolerant nitrogenase is extremely unlikely.

SUBMITTER: MacKellar D

PROVIDER: S-EPMC4735515 | biostudies-literature | 2016 Feb

REPOSITORIES: biostudies-literature

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Streptomyces thermoautotrophicus does not fix nitrogen.

MacKellar Drew D Lieber Lucas L Norman Jeffrey S JS Bolger Anthony A Tobin Cory C Murray James W JW Oksaksin Mehtap M Chang Roger L RL Ford Tyler J TJ Nguyen Peter Q PQ Woodward Jimmy J Permingeat Hugo R HR Joshi Neel S NS Silver Pamela A PA Usadel Björn B Rutherford Alfred W AW Friesen Maren L ML Prell Jürgen J

Scientific reports 20160201

Streptomyces thermoautotrophicus UBT1 has been described as a moderately thermophilic chemolithoautotroph with a novel nitrogenase enzyme that is oxygen-insensitive. We have cultured the UBT1 strain, and have isolated two new strains (H1 and P1-2) of very similar phenotypic and genetic characters. These strains show minimal growth on ammonium-free media, and fail to incorporate isotopically labeled N2 gas into biomass in multiple independent assays. The sdn genes previously published as the puta ...[more]

PMID: 26833023

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Streptomyces thermoautotrophicus does not fix nitrogen.

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Streptomyces thermoautotrophicus does not fix nitrogen.

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