Cloning of the gene coding for the outer membrane receptor protein for ferric pseudobactin, a siderophore from a plant growth-promoting Pseudomonas strain.

ABSTRACT Eight genes have been identified that function in the regulation, biosynthesis, and transport of rhizobactin 1021, a hydroxamate siderophore produced under iron stress bySinorhizobium meliloti. The genes were sequenced, and transposon insertion mutants were constructed for phenotypic analysis. Six of the genes, named rhbABCDEF, function in the biosynthesis of the siderophore and were shown to constitute an operon that is repressed under iron-replete conditions. Another gene in the cluster, named rhtA, encodes the outer membrane receptor protein for rhizobactin 1021. It was shown to be regulated by iron and to encode a product having 61% similarity to IutA, the outer membrane receptor for aerobactin. Transcription of both therhbABCDEF operon and the rhtA gene was found to be positively regulated by the product of the eighth gene in the cluster, named rhrA, which has characteristics of an AraC-type transcriptional activator. The six genes in therhbABCDEF operon have interesting gene junctions with short base overlaps existing between the genes. Similarities between the protein products of the biosynthesis genes and other proteins suggest that rhizobactin 1021 is synthesized by the formation of a novel siderophore precursor, 1,3-diaminopropane, which is then modified and attached to citrate in steps resembling those of the aerobactin biosynthetic pathway. The cluster of genes is located on the pSyma megaplasmid of S. meliloti 2011. Reverse transcription-PCR with RNA isolated from mature alfalfa nodules yielded no products for rhbF or rhtA at a time when the nifH gene was strongly expressed, indicating that siderophore biosynthesis and transport genes are not strongly expressed when nitrogenase is being formed in root nodules. Mutants having transposon insertions in the biosynthesis or transport genes induced effective nitrogen-fixing nodules on alfalfa plants.

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Complete Genome Sequence of the Rhizobacterium Pseudomonas trivialis Strain IHBB745 with Multiple Plant Growth-Promoting Activities and Tolerance to Desiccation and Alkalinity

Genome Announcements ◽

10.1128/genomea.00943-15 ◽

2015 ◽

Vol 3 (5) ◽

Cited By ~ 7

Author(s):

Arvind Gulati ◽

Mohit Kumar Swarnkar ◽

Pratibha Vyas ◽

Praveen Rahi ◽

Rishu Thakur ◽

...

Keyword(s):

Plant Growth ◽

Genome Sequence ◽

Complete Genome Sequence ◽

Complete Genome ◽

Acc Deaminase ◽

Gene Coding ◽

Plant Growth Promoting Activities ◽

Plant Growth Promoting ◽

Growth Promoting ◽

Indole 3 Acetic Acid

The complete genome sequence of 6.45 Mb is reported here for Pseudomonas trivialis strain IHBB745 (MTCC 5336), which is an efficient, stress-tolerant, and broad-spectrum plant growth-promoting rhizobacterium. The gene-coding clusters predicted the genes for phosphate solubilization, siderophore production, 1-aminocyclopropane-1-carboxylate (ACC) deaminase activity, indole-3-acetic acid (IAA) production, and stress response.

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Normal iron-enterochelin uptake in mutants lacking the colicin I outer membrane receptor protein of Escherichia coli.

Journal of Bacteriology ◽

10.1128/jb.130.3.1399-1401.1977 ◽

1977 ◽

Vol 130 (3) ◽

pp. 1399-1401 ◽

Cited By ~ 1

Author(s):

S Soucek ◽

J Konisky

Keyword(s):

Escherichia Coli ◽

Outer Membrane ◽

Membrane Receptor ◽

Receptor Protein ◽

Outer Membrane Receptor

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Identification of rhtX and fptX, Novel Genes Encoding Proteins That Show Homology and Function in the Utilization of the Siderophores Rhizobactin 1021 by Sinorhizobium meliloti and Pyochelin by Pseudomonas aeruginosa, Respectively

Journal of Bacteriology ◽

10.1128/jb.186.10.2996-3005.2004 ◽

2004 ◽

Vol 186 (10) ◽

pp. 2996-3005 ◽

Cited By ~ 54

Author(s):

Páraic Ó Cuív ◽

Paul Clarke ◽

Damien Lynch ◽

Michael O'Connell

Keyword(s):

Pseudomonas Aeruginosa ◽

Outer Membrane ◽

Membrane Transport ◽

Sinorhizobium Meliloti ◽

Iron Acquisition ◽

Membrane Receptor ◽

Receptor Protein ◽

Outer Membrane Receptor ◽

E Coli ◽

Genes Encoding

ABSTRACT Rhizobactin 1021 is a hydroxymate siderophore produced by the soil bacterium Sinorhizobium meliloti 2011. A regulon comprising rhtA, encoding the outer membrane receptor protein for the ferrisiderophore; the biosynthesis operon rhbABCDEF; and rhrA, the Ara-C-like regulator of the receptor and biosynthesis genes has been previously described. We report the discovery of a gene, located upstream of rhbA and named rhtX (for “rhizobactin transport”), which is required, in addition to rhtA, to confer the ability to utilize rhizobactin 1021 on a strain of S. meliloti that does not naturally utilize the siderophore. Rhizobactin 1021 is structurally similar to aerobactin, which is transported in Escherichia coli via the IutA outer membrane receptor and the FhuCDB inner membrane transport system. E. coli expressing iutA and fhuCDB was found to also transport rhizobactin 1021. We demonstrated that RhtX alone could substitute for FhuCDB to transport rhizobactin 1021 in E. coli. RhtX shows similarity to a number of uncharacterized proteins which are encoded proximal to genes that are either known to be or predicted to be involved in iron acquisition. Among these is PA4218 of Pseudomonas aeruginosa, which is located close to the gene cluster that functions in pyochelin biosynthesis and outer membrane transport. PA4218 was mutated by allelic replacement, and the mutant was found to have a pyochelin utilization-defective phenotype. It is proposed that PA4218 be named fptX (for “ferripyochelin transport”). RhtX and FptX appear to be members of a novel family of permeases that function as single-subunit transporters of siderophores.

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Characterization of the pColV-K30 encoded cloacin DF13/aerobactin outer membrane receptor protein ofEscherichia coli; isolation and purification of the protein and analysis of its nucleotide sequence and primary structure

FEMS Microbiology Letters ◽

10.1111/j.1574-6968.1985.tb01583.x ◽

1985 ◽

Vol 26 (2) ◽

pp. 153-161 ◽

Cited By ~ 34

Author(s):

Willy J.A. Krone ◽

Freek Stegehuis ◽

Gregory Koningstein ◽

Carla Doorn ◽

Bert Roosendaal ◽

...

Keyword(s):

Nucleotide Sequence ◽

Outer Membrane ◽

Primary Structure ◽

Membrane Receptor ◽

Ofescherichia Coli ◽

Receptor Protein ◽

Outer Membrane Receptor ◽

Isolation And Purification

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In vitro binding of cloacin DF13 to its purified outer membrane receptor protein and effect of peptidoglycan on bacteriocin-receptor interaction.

Journal of Bacteriology ◽

10.1128/jb.140.3.964-970.1979 ◽

1979 ◽

Vol 140 (3) ◽

pp. 964-970 ◽

Cited By ~ 6

Author(s):

B Oudega ◽

J van der Molen ◽

F K de Graaf

Keyword(s):

Outer Membrane ◽

Membrane Receptor ◽

Receptor Protein ◽

Receptor Interaction ◽

Outer Membrane Receptor ◽

In Vitro Binding ◽

Vitro Binding

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Essential Role of the Iron-Regulated Outer Membrane Receptor FauA in Alcaligin Siderophore-Mediated Iron Uptake inBordetella Species

Journal of Bacteriology ◽

10.1128/jb.181.19.5958-5966.1999 ◽

1999 ◽

Vol 181 (19) ◽

pp. 5958-5966 ◽

Cited By ~ 46

Author(s):

Timothy J. Brickman ◽

Sandra K. Armstrong

Keyword(s):

Outer Membrane ◽

Membrane Receptor ◽

Receptor Protein ◽

Amino Acid Sequence Similarity ◽

Nucleotide Sequencing ◽

Insertion Mutant ◽

Wild Type ◽

Outer Membrane Receptor ◽

Iron Starvation ◽

High Amino Acid

ABSTRACT Phenotypic analysis using heterologous host systems localized putative Bordetella pertussis ferric alcaligin transport genes and Fur-binding sequences to a 3.8-kb genetic region downstream from the alcR regulator gene. Nucleotide sequencing identified a TonB-dependent receptor family homolog gene,fauA, predicted to encode a polypeptide with high amino acid sequence similarity with known bacterial ferric siderophore receptors. In Escherichia coli, the fauA genes of both B. pertussis and Bordetella bronchiseptica directed the production of a 79-kDa polypeptide, approximating the predicted size of the mature FauA protein. B. bronchiseptica fauA insertion mutant BRM17 was unable to utilize ferric alcaligin, and in complementation analyses ferric alcaligin utilization was restored to this mutant by supplying the wild-typefauA gene in trans. Mutant BRM18, carrying a nonpolar in-frame fauA deletion mutation, was defective in ferric alcaligin utilization and 55Fe-ferric alcaligin uptake and no longer produced a 79-kDa iron-regulated outer membrane protein. In complementation analyses, BRM18 merodiploids bearing the wild-type fauA gene in trans regained ferric alcaligin siderophore transport and utilization functions and produced the 79-kDa protein. Analysis of a plasmid-borne fauA-lacZoperon fusion confirmed that fauA is subject to iron regulation at the transcriptional level and that cis-acting transcriptional control elements mediating fauA iron repressibility reside within the 3.8-kb PstIfauA DNA region. Moreover, expression of thefauA-lacZ fusion gene under iron starvation conditions was shown to be alcR dependent. FauA is a 79-kDa iron-regulated outer membrane receptor protein required for transport and utilization of ferric alcaligin siderophore complexes by Bordetellaspecies.

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Draft Genome Sequence of the Plant Growth-Promoting Streptomyces sp. Strain 6-11-2

Microbiology Resource Announcements ◽

10.1128/mra.00877-19 ◽

2019 ◽

Vol 8 (47) ◽

Author(s):

Ayman Ztouti ◽

Natsumi Saito ◽

Junna Sasaki ◽

Takashi Yamaguchi ◽

Nobuo Araki ◽

...

Keyword(s):

Plant Growth ◽

Genome Sequence ◽

Draft Genome ◽

Trna Genes ◽

Streptomyces Sp ◽

Coding Regions ◽

Gene Coding ◽

A Genome ◽

Plant Growth Promoting ◽

Growth Promoting

A genome sequence of Streptomyces sp. strain 6-2-11, a bacterium capable of promoting plant growth, was determined using the Illumina NovaSeq and MinION sequencers. An 8.9-Mb genome sequence composed of 3 contigs was successfully assembled, where 7,980 gene-coding regions, 6 rrn operons, and 86 tRNA genes were located.

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