Different Ancestries of R Tailocins in Rhizospheric<i>Pseudomonas</i>Isolates

Ghequire, Maarten G. K.; Dillen, Yörg; Lambrichts, Ivo; Proost, Paul; Wattiez, Ruddy; Mot, René De

doi:10.1093/gbe/evv184

Cited by 52 publications

(93 citation statements)

References 102 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The genes in the lysis cassette flank the region containing the structural genes, with the holin gene upstream and the endolysin and spanin complex genes downstream of the structural genes. The region encoding the tailocin structural genes is nearly twice the size and has twice the number of ORFs as the genomic regions containing the R-tailocin structural genes previously described for other plant-associated pseudomonads (6,11,16,17). This region can be divided into two smaller regions, each containing the genes required for the assembly of different R-tailocins (Fig.…”

Section: Resultsmentioning

confidence: 95%

“…The cluster contains genes annotated as functioning in regulation, cell lysis and tailocin release, and tailocin particle assembly as well as cargo genes encoding proteins potentially carried with the tailocins (11,23). At the beginning of the cluster, adjacent to mutS, is a gene with significant nucleotide sequence similarity to ptrR, the negative regulator of tailocin gene transcription in P. aeruginosa (11,23). The cluster also contains a lysis cassette that consists of genes encoding a holin, an endolysin, and spanin complex involved in cell lysis and tailocin release.…”

Section: Resultsmentioning

confidence: 99%

“…The bacteriophage lysis cassette is composed of genes encoding the endolysin, holin, and the Rz and Rz1 proteins comprising the spanin complex (10). Some tailocin gene clusters encode all three lysis cassette components, while others, such as those in P. aeruginosa, generally do not encode the spanin complex (11). Endolysins are cytoplasmic proteins that catalyze the degradation of the cell wall peptidoglycan layer.…”

mentioning

confidence: 99%

“…More recently, R-tailocins similar to those produced by P. aeruginosa have been identified in plant-associated Pseudomonas strains (11,16,17,23,24), suggesting that R-tailocin production may be an important competitive determinant of bacterial interactions for Pseudomonas inhabiting diverse environments, such as the plant microbiome. In the present study, we focused on Pseudomonas chlororaphis 30-84, a rhizosphere-colonizing strain selected for its ability to suppress take-all disease of wheat, caused by the fungal plant pathogen Gaeumannomyces graminis var.…”

mentioning

confidence: 99%

“…Previous comparison of the R-tailocin gene clusters among Pseudomonas strains revealed distinct evolutionary ancestries based on the protein sequences of the structural components that may be influenced by bacterial habitat (11,16). Analysis of the P. chlororaphis 30-84 R-tailocin gene cluster suggested a unique evolutionary trajectory because it contains structural components with similarity to both P. aeruginosa and P. syringae, potentially representing a hybrid tailocin (16).…”

mentioning

confidence: 99%

See 4 more Smart Citations

Pseudomonas chlororaphis Produces Two Distinct R-Tailocins That Contribute to Bacterial Competition in Biofilms and on Roots

Dorosky

Pierson

et al. 2017

Appl Environ Microbiol

View full text Add to dashboard Cite

R-type tailocins are high-molecular-weight bacteriocins that resemble bacteriophage tails and are encoded within the genomes of many Pseudomonas species. In this study, analysis of the P. chlororaphis 30-84 R-tailocin gene cluster revealed that it contains the structural components to produce two R-tailocins of different ancestral origins. Two distinct R-tailocin populations differing in length were observed in UV-induced lysates of P. chlororaphis 30-84 via transmission electron microscopy. Mutants defective in the production of one or both R-tailocins demonstrated that the killing spectrum of each tailocin is limited to Pseudomonas species. The spectra of pseudomonads killed by the two R-tailocins differed, although a few Pseudomonas species were either killed by or insusceptible to both tailocins. Tailocin release was disrupted by deletion of the holin gene within the tailocin gene cluster, demonstrating that the lysis cassette is required for the release of both R-tailocins. The loss of functional tailocin production reduced the ability of P. chlororaphis 30-84 to compete with an R-tailocin-sensitive strain within biofilms and rhizosphere communities. Our study demonstrates that Pseudomonas species can produce more than one functional R-tailocin particle sharing the same lysis cassette but differing in their killing spectra. This study provides evidence for the role of R-tailocins as determinants of bacterial competition among plant-associated Pseudomonas in biofilms and the rhizosphere.IMPORTANCE Recent studies have identified R-tailocin gene clusters potentially encoding more than one R-tailocin within the genomes of plant-associated Pseudomonas but have not demonstrated that more than one particle is produced or the ecological significance of the production of multiple R-tailocins. This study demonstrates for the first time that Pseudomonas strains can produce two distinct R-tailocins with different killing spectra, both of which contribute to bacterial competition between rhizosphere-associated bacteria. These results provide new insight into the previously uncharacterized role of R-tailocin production by plant-associated Pseudomonas species in bacterial population dynamics within surface-attached biofilms and on roots.KEYWORDS R-tailocin, bacterial competition, rhizosphere, Pseudomonas, bacteriocins, microbial ecology, rhizosphere-inhabiting microbes B acteria produce a diversity of bacteriocins to kill closely related competitors (1). Tailocins are high-molecular-weight (HMW) bacteriocins produced by a variety of bacteria that resemble bacteriophage tails (2-5). Tailocin particles are protease resistant, thermolabile, and sedimentable by ultracentrifugation (2). These particles have been studied extensively for the opportunistic human pathogen Pseudomonas aeruginosa, strains of which are capable of producing either or both R-type and F-type

show abstract

Section: Resultsmentioning

confidence: 95%

Section: Resultsmentioning

confidence: 99%

mentioning

confidence: 99%

mentioning

confidence: 99%

mentioning

confidence: 99%

See 3 more Smart Citations

Pseudomonas chlororaphis Produces Two Distinct R-Tailocins That Contribute to Bacterial Competition in Biofilms and on Roots

Dorosky

Pierson

et al. 2017

Appl Environ Microbiol

View full text Add to dashboard Cite

show abstract

Biosynthetic Origin of the Antibiotic Pseudopyronines A and B in Pseudomonas putida BW11M1

et al. 2015

View full text Add to dashboard Cite

Within the framework of our effort to discover new antibiotics from pseudomonads, pseudopyronines A and B were isolated from the plant-derived Pseudomonas putida BW11M1. Pseudopyronines are 3,6-dialkyl-4-hydroxy-2-pyrones and displayed high in vitro activities against several human pathogens, and in our hands also towards the plant pathogen Pseudomonas savastanoi. Here, the biosynthesis of pseudopyronine B was studied by a combination of feeding experiments with isotopically labeled precursors, genomic sequence analysis, and gene deletion experiments. The studies resulted in the deduction of all acetate units and revealed that the biosynthesis of these α-pyrones occurs with a single PpyS-homologous ketosynthase. It fuses, with some substrate flexibility, a 3-oxo-fatty acid and a further unbranched saturated fatty acid, both of medium chain-length and provided by primary metabolism.

show abstract

Identification and functional analysis of a bacteriocin, pyocin S6, with ribonuclease activity from a Pseudomonas aeruginosa cystic fibrosis clinical isolate

et al. 2016

Self Cite

View full text Add to dashboard Cite

S‐type pyocins are bacteriocins produced by Pseudomonas aeruginosa isolates to antagonize or kill other strains of the same species. They have a modular organization comprising a receptor‐binding domain recognizing a surface constituent of the target bacterium, a domain for translocation through the periplasm, and a killing or toxic domain with DNase, tRNase, or pore‐forming activity. Pyocins S2, S3, S4, and S5 recognize TonB‐dependent ferri‐siderophore receptors in the outer membrane. We here describe a new nuclease bacteriocin, pyocin S6, encoded in the genome of a P. aeruginosa cystic fibrosis (CF) clinical isolate, CF_PA39. Similarly to pyocins S1 and S2, the S6 toxin–immunity gene tandem was recruited to the genomic region encoding exotoxin A. The pyocin S6 receptor‐binding and translocation domains are identical to those of pyocin S1, whereas the killing domain is similar to the 16S ribonuclease domain of Escherichia coli colicin E3. The cytotoxic activity was abolished in pyocin S6 forms with a mutation in the colicin E3‐equivalent catalytic motif. The CF_PA39 S6 immunity gene displays a higher expression level than the gene encoding the killing protein, the latter being only detected when bacteria are grown under iron‐limiting conditions. In the S1‐pyocinogenic strain P. aeruginosa ATCC 25324 and pyocin S2 producer P. aeruginosa PAO1, a remnant of the pyocin S6 killing domain and an intact S6‐type immunity gene are located downstream of their respective pyocin operons. Strain PAO1 is insensitive for pyocin S6, and its S6‐type immunity gene provides protection against pyocin S6 activity. Purified pyocin S6 inhibits one‐fifth of 110 P. aeruginosa CF clinical isolates tested, showing clearer inhibition zones when the target cells are grown under iron limitation. In this panel, about half of the CF clinical isolates were found to host the S6 genes. The pyocin S6 locus is also present in the genome of some non‐CF clinical isolates.

show abstract

Different Ancestries of R Tailocins in RhizosphericPseudomonasIsolates

Cited by 52 publications

References 102 publications

Pseudomonas chlororaphis Produces Two Distinct R-Tailocins That Contribute to Bacterial Competition in Biofilms and on Roots

Pseudomonas chlororaphis Produces Two Distinct R-Tailocins That Contribute to Bacterial Competition in Biofilms and on Roots

Biosynthetic Origin of the Antibiotic Pseudopyronines A and B in Pseudomonas putida BW11M1

Identification and functional analysis of a bacteriocin, pyocin S6, with ribonuclease activity from a Pseudomonas aeruginosa cystic fibrosis clinical isolate

Contact Info

Product

Resources

About