scholarly journals FrpA is the outer membrane piscibactin transporter in Vibrio anguillarum: structural elements in synthetic piscibactin analogues required for transport

2021 ◽  
Author(s):  
Marta A. Lages ◽  
M. Carmen de la Fuente ◽  
Lucía Ageitos ◽  
Diana Martínez-Matamoros ◽  
Jaime Rodríguez ◽  
...  
Keyword(s):  
Outer Membrane ◽  
Vibrio Anguillarum ◽  
Hydroxyl Group ◽  
Thiazole Ring ◽  
Antimicrobial Compounds ◽  
Structural Elements ◽  
Fish Pathogens ◽  
Major Virulence Factor ◽  
Photobacterium Damselae ◽  
Outer Membrane Transporter

AbstractPiscibactin (Pcb) is a labile siderophore widespread among Vibrionaceae. Its production is a major virulence factor of some fish pathogens such as Photobacterium damselae subsp. piscicida and Vibrio anguillarum. Although FrpA was previously suggested as the putative outer membrane transporter (OMT) for ferri-piscibactin, its role in piscibactin uptake was never demonstrated. In this work, we generated mutants of V. anguillarum defective in FrpA and analyzed their ability to use piscibactin as iron source. The results showed that inactivation of frpA completely disables piscibactin utilization, and the original phenotype could be restored by gene complementation, confirming that FrpA is the OMT that mediates ferri-Pcb uptake. Additionally, the ability of several Pcb thiazole analogues, with different configurations at positions 9, 10, and 13, to be internalized through FrpA, was evaluated measuring their ability to promote growth under iron deficiency of several indicator strains. The results showed that while those analogues with a thiazole ring maintain almost the same activity as Pcb, the maintenance of the hydroxyl group present in natural piscibactin configuration at position C-13 is crucial for Fe3+ chelation and, in consequence, for the recognition of the ferri-siderophore by the cognate OMT. All these findings allowed us to propose a Pcb analogue as a good candidate to vectorize antimicrobial compounds, through the Trojan horse strategy, to develop novel compounds against bacterial fish diseases. Graphical abstract

Characterization of the surface antigens of the marine fish pathogens Vibrio anguillarum and Vibrio ordalii

1984 ◽  
Vol 30 (5) ◽  
pp. 703-710 ◽  
Author(s):  
Henrik Chart ◽  
Trevor J. Trust
Keyword(s):  
Outer Membrane ◽  
Chain Length ◽  
Extraction Procedure ◽  
Vibrio Anguillarum ◽  
Surface Antigens ◽  
Cross Reactivity ◽  
Antigenic Specificity ◽  
Fish Pathogens ◽  
Morphological Heterogeneity ◽  
Vibrio Ordalii

The technique of immunoblotting was used to identify the surface antigens of the marine vibrios pathogenic for fish, Vibrio anguillarum and Vibrio ordalii. Polyclonal antisera raised in rabbits to strains representing the two most common serotypes causing Vibriosis in fish in North America were used. The results demonstrated that antigenic specificity was conferred by the lipopolysaccharides, with three serotypes being displayed among the strains examined. The lipopolysaccharides of strains chosen as type species for V. anguillarum and V. ordalii displayed antigenic cross-reactivity. The morphological heterogeneity of the Vibrio lipopolysaccharides was also analyzed in silver-stained polyacrylamide gels and by intrinsic 32P-radiolabelling. Two distinct lipopolysaccharide morphologies were exhibited, one with 0 polysaccharide chains of heterogeneous chain length, the other having 0 polysaccharide chains of more uniform chain length but displaying microheterogeneity. These lipopolysaccharide morphologies corresponded to different serogroups. Two minor proteins of apparent molecular weights 49 000 – 51 000 present in outer membrane preparations isolated by the sarcosinate extraction procedure were also strong antigens, and common to all strains of V. anguillarum tested and to several strains of V. ordalii. The major outer membrane protein was a weak antigen common to both species.

Ultraviolet Treatment of Water for Destruction of Five Gram-Negative Bacteria Pathogenic to Fishes

1977 ◽  
Vol 34 (8) ◽  
pp. 1244-1249 ◽  
Author(s):  
G. L. Bullock ◽  
H. M. Stuckey
Keyword(s):  
Particulate Matter ◽  
Ultraviolet Irradiation ◽  
Vibrio Anguillarum ◽  
Spring Water ◽  
Aeromonas Salmonicida ◽  
Water Disinfection ◽  
Gram Negative Bacteria ◽  
Fish Pathogens ◽  
Gram Negative ◽  
Ultraviolet Treatment

Filtration (25 nm) and ultraviolet irradiation dosages of 13,100–29,400 microwatt seconds per square centimetre (μW∙s∙cm−2) effected a 99.98–100% reduction of five gram-negative fish pathogens — Aeromonas salmonicida, A. hydrophila, Vibrio anguillarum, Pseudomonas fluorescens, and the enteric redmouth organism in 12.5 °C clear spring water or spring water containing particulate matter. Filtration and a dosage of 4500 μW∙s∙cm−2 killed 99.83–100% of test strains in spring water and 4000–4750 μW∙s∙cm−2 killed 99.33–99.99% in water with particulate matter. Irradiation of unfiltered water containing particulate matter was less effective, especially at dosages of 5000 μW∙s∙cm−2 or less, which killed 97–99.94% of strains. Filtration and 13,100 μW∙s∙cm−2 irradiation of water containing A. salmonicida prevented transmission of furunculosis. Key words: ultraviolet irradiation, bacterial fish pathogens, water disinfection

scholarly journals The Fish Pathogen Vibrio ordalii Under Iron Deprivation Produces the Siderophore Piscibactin

2019 ◽  
Vol 7 (9) ◽  
pp. 313 ◽  
Author(s):  
Pamela Ruiz ◽  
Miguel Balado ◽  
Juan Carlos Fuentes-Monteverde ◽  
Alicia E. Toranzo ◽  
Jaime Rodríguez ◽  
...  
Keyword(s):  
Gene Cluster ◽  
Iron Uptake ◽  
Peptide Mass Fingerprinting ◽  
Iron Limitation ◽  
Fish Pathogen ◽  
Fish Pathogens ◽  
Iron Deprivation ◽  
Peptide Mass ◽  
Photobacterium Damselae ◽  
Vibrio Ordalii

Vibrio ordalii is the causative agent of vibriosis, mainly in salmonid fishes, and its virulence mechanisms are still not completely understood. In previous works we demonstrated that V. ordalii possess several iron uptake mechanisms based on heme utilization and siderophore production. The aim of the present work was to confirm the production and utilization of piscibactin as a siderophore by V. ordalii. Using genetic analysis, identification by peptide mass fingerprinting (PMF) of iron-regulated membrane proteins and chemical identification by LC-HRMS, we were able to clearly demonstrate that V. ordalii produces piscibactin under iron limitation. The synthesis and transport of this siderophore is encoded by a chromosomal gene cluster homologous to another one described in V. anguillarum, which also encodes the synthesis of piscibactin. Using β-galactosidase assays we were able to show that two potential promoters regulated by iron control the transcription of this gene cluster in V. ordalii. Moreover, biosynthetic and transport proteins corresponding to piscibactin synthesis and uptake could be identified in membrane fractions of V. ordalii cells grown under iron limitation. The synthesis of piscibactin was previously reported in other fish pathogens like Photobacterium damselae subsp. piscicida and V. anguillarum, which highlights the importance of this siderophore as a key virulence factor in Vibrionaceae bacteria infecting poikilothermic animals.

Molecular characterization of Vibrio anguillarum biotype 2

1981 ◽  
Vol 27 (10) ◽  
pp. 1011-1018 ◽  
Author(s):  
Michael H. Schiewe ◽  
Jorge H. Crosa
Keyword(s):  
Vibrio Anguillarum ◽  
Virulence Plasmid ◽  
Multicopy Plasmid ◽  
Nick Translation ◽  
Fish Pathogens ◽  
Mole Percent ◽  
Discrete Nature ◽  
Sequence Relationships ◽  
Restriction Endonuclease Cleavage

Examination of polynucleotide sequence relationships among 11 strains of Vibrio anguillarum biotype 2 isolated from moribund fish in North America and Japan demonstrated the highly conserved character of this group of fish pathogens and, moreover, confirmed its discrete nature from V. anguillarum biotype 1. Additional molecular analyses of the V. anguillarum biotype 2 strains revealed the universal presence of a multicopy plasmid with a molecular mass of approximately 20 × 106 daltons and a mole percent guanine plus cytosine of 44. The plasmid of strain DF3K was representative of this molecular species and was designated pMJ101. Subsequent DNA–DNA hybridizations using nick translation-labeled pMJ101 as a probe indicated all the 20 × 106 dalton plasmids were either identical or highly conserved, and, furthermore, that pMJ101 was apparently unrelated to either the virulence plasmid, pJM1, of V. anguillarum biotype 1 or to representatives of common plasmid incompatibility groups. The lack of relatedness between pMJ101 and pJM1 was further supported by differences in their restriction endonuclease cleavage patterns.

scholarly journals Antibiotic-Mediated Modulations of Outer Membrane Vesicles in Enterohemorrhagic Escherichia coli O104:H4 and O157:H7

2017 ◽  
Vol 61 (9) ◽  
Author(s):  
Andreas Bauwens ◽  
Lisa Kunsmann ◽  
Helge Karch ◽  
Alexander Mellmann ◽  
Martina Bielaszewska
Keyword(s):  
Escherichia Coli ◽  
Outer Membrane ◽  
Shiga Toxin ◽  
Membrane Vesicles ◽  
Polymyxin B ◽  
Outer Membrane Vesicles ◽  
Enterohemorrhagic Escherichia Coli ◽  
Content Type ◽  
E Coli ◽  
Major Virulence Factor

ABSTRACT Ciprofloxacin, meropenem, fosfomycin, and polymyxin B strongly increase production of outer membrane vesicles (OMVs) in Escherichia coli O104:H4 and O157:H7. Ciprofloxacin also upregulates OMV-associated Shiga toxin 2a, the major virulence factor of these pathogens, whereas the other antibiotics increase OMV production without the toxin. These two effects might worsen the clinical outcome of infections caused by Shiga toxin-producing E. coli. Our data support the existing recommendations to avoid antibiotics for treatment of these infections.

scholarly journals Antimicrobial Peptides Protect Coho Salmon fromVibrio anguillarum Infections

2000 ◽  
Vol 66 (5) ◽  
pp. 1928-1932 ◽  
Author(s):  
X. Jia ◽  
A. Patrzykat ◽  
R. H. Devlin ◽  
P. A. Ackerman ◽  
G. K. Iwama ◽  
...  
Keyword(s):  
Antimicrobial Peptides ◽  
Coho Salmon ◽  
Vibrio Anguillarum ◽  
Transgenic Fish ◽  
In Vivo Studies ◽  
Bacterial Disease ◽  
Control Groups ◽  
Fish Pathogens

ABSTRACT Fish losses from infectious diseases are a significant problem in aquaculture worldwide. Therefore, we investigated the ability of cationic antimicrobial peptides to protect against infection caused by the fish pathogen Vibrio anguillarum. To identify effective peptides for fish, the MICs of certain antimicrobial peptides against fish pathogens were determined in vitro. Two of the most effective antimicrobial peptides, CEME, a cecropin-melittin hybrid peptide, and pleurocidin amide, a C-terminally amidated form of the natural flounder peptide, were selected for in vivo studies. A single intraperitoneal injection of CEME did not affect mortality rates in juvenile coho salmon infected with V. anguillarum, the causative agent of vibriosis. Therefore, the peptides were delivered continuously using miniosmotic pumps placed in the peritoneal cavity. Twelve days after pump implantation, the fish received intraperitoneal injections ofV. anguillarum at a dose that would kill 50 to 90% of the population. Fish receiving 200 μg of CEME per day survived longer and had significantly lower accumulated mortalities (13%) than the control groups (50 to 58%). Fish receiving pleurocidin amide at 250 μg per day also survived longer and had significantly lower accumulated mortalities (5%) than the control groups (67 to 75%). This clearly shows the potential for antimicrobial peptides to protect fish against infections and indicates that the strategy of overexpressing the peptides in transgenic fish may provide a method of decreasing bacterial disease problems.

scholarly journals Identification and characterization of Pseudomonas membrane transporters necessary for utilization of the siderophore pyridine-2,6-bis(thiocarboxylic acid) (PDTC)

Microbiology ◽  
2006 ◽  
Vol 152 (10) ◽  
pp. 3157-3166 ◽  
Author(s):  
Lynne H. Leach ◽  
Thomas A. Lewis
Keyword(s):  
Outer Membrane ◽  
Transcriptional Activation ◽  
Iron Acquisition ◽  
Membrane Transporters ◽  
Membrane Transporter ◽  
Inner Membrane ◽  
Thiocarboxylic Acid ◽  
Outer Membrane Transporter ◽  
Identification And Characterization

The compound pyridine-2,6-bis(thiocarboxylic acid) (PDTC) is known to be produced and excreted by three strains of Pseudomonas. Its reactivity includes the complete dechlorination of the environmental contaminant carbon tetrachloride. PDTC functions as a siderophore; however, roles as a ferric reductant and antimicrobial agent have also been proposed. PDTC function and regulation were further explored by characterizing the phenotypes of mutants in predicted membrane transporter genes. The functions of a predicted outer-membrane transporter (PdtK) and a predicted inner-membrane permease (PdtE) were examined in Pseudomonas putida DSM 3601. Uptake of iron from 55Fe(III):PDTC, and bioutilization of PDTC in a chelated medium, were dependent upon PdtK and PdtE. Another strain of P. putida (KT2440), which lacks pdt orthologues, showed growth inhibition by PDTC that could be relieved by introducing a plasmid containing pdtKCPE. Transcriptional activation in response to exogenously added PDTC (25 μM) was unaltered by the pdtK or pdtE mutations; each mutant showed activation of a pdt transcriptional reporter, indistinguishable from an isogenic PDTC utilization-proficient strain. The data demonstrate that PdtK and PdtE constitute a bipartite outer-membrane/inner-membrane transport system for iron acquisition from Fe(III):PDTC. Disruptions in this portion of the P. putida DSM 3601 pdt gene cluster do not abolish PDTC-dependent transcriptional signalling.

Sign in / Sign up

Export Citation Format

Share Document