The fish pathogen flavobacterium columnare represents four distinct species: flavobacterium columnare, flavobacterium covae sp. nov., flavobacterium davisii sp. nov. and flavobacterium oreochromis sp. nov., and emended description of flavobacterium columnare

2021 ◽  
pp. 126293
Author(s):  
Benjamin R. LaFrentz ◽  
Stanislava Králová ◽  
Claire R. Burbick ◽  
Trevor L. Alexander ◽  
Conner W. Phillips ◽  
...  
Keyword(s):  
Distinct Species ◽  
Flavobacterium Columnare ◽  
Fish Pathogen ◽  
Emended Description

scholarly journals Rich resource environment of fish farms facilitates phenotypic variation and virulence in an opportunistic fish pathogen

2020 ◽  
Author(s):  
Katja Pulkkinen ◽  
Tarmo Ketola ◽  
Jouni Laakso ◽  
Johanna Mappes ◽  
Lotta-Riina Sundberg
Keyword(s):  
Growth Rate ◽  
Natural Water ◽  
Phenotypic Variation ◽  
Water Environment ◽  
High Growth ◽  
Flavobacterium Columnare ◽  
Bacterial Survival ◽  
Fish Pathogen ◽  
Fish Farms ◽  
Host Environment

SummaryPhenotypic variation allows adaptation of opportunistic pathogens to variable conditions in the outside-host environment with strong effects on their epidemiology and pathogenicity in hosts. Here we found that the isolates of an opportunistic fish pathogen Flavobacterium columnare from fish farming environment had higher phenotypic variation between two morphotypes in growth, as compared to the isolates from the natural water environment. The rough morphotypes had higher growth rate than the rhizoid morphotypes especially in the higher resource concentrations and in the higher temperature, but only if the isolate was originating from the fish farms. Rhizoid morphotype was more virulent than the rough type regardless of their origin. However, the virulence of the rough type increased sharply with the size of the fish, and the bacterial isolates from the gills of diseased fish were rhizoid type, indicating a reversal of the rough morphotype into rhizoid in contact with the fish. The high growth rate of the rough morphotype combined with the morphotype reversibility could increase the probability of columnaris epidemics at fish farms. Our findings suggest that intensive farming imposes different selection pressures on bacterial survival in the outside-host environment and its transmission compared to the natural water environment.

scholarly journals Complete Genome Sequence of Fish Pathogen Flavobacterium columnare Strain B185, Originating from Finland

2019 ◽  
Vol 8 (49) ◽  
Author(s):  
Janne J. Ravantti ◽  
Elina Laanto ◽  
Petri Papponen ◽  
Lotta-Riina Sundberg
Keyword(s):  
Genome Sequence ◽  
Complete Genome Sequence ◽  
Complete Genome ◽  
Flavobacterium Columnare ◽  
Fish Pathogen ◽  
Sequencing Technology ◽  
Content Type ◽  
Pacbio Rs Ii ◽  
Circular Genome

We report a complete genome sequence of a Finnish isolate of the fish pathogen Flavobacterium columnare. Using PacBio RS II sequencing technology, the complete circular genome of F. columnare strain B185 with 3,261,404 bp was obtained.

scholarly journals Prophages and Past Prophage-Host Interactions Revealed by CRISPR Spacer Content in a Fish Pathogen

2020 ◽  
Vol 8 (12) ◽  
pp. 1919
Author(s):  
Elina Laanto ◽  
Janne J. Ravantti ◽  
Lotta-Riina Sundberg
Keyword(s):  
Flavobacterium Columnare ◽  
Strain Atcc ◽  
Human Pathogens ◽  
Fish Pathogen ◽  
Bacterial Strains ◽  
Host Interactions ◽  
Different Strains ◽  
Gene Orthologs ◽  
Similar Genome Organization

The role of prophages in the evolution, diversification, or virulence of the fish pathogen Flavobacterium columnare has not been studied thus far. Here, we describe a functional spontaneously inducing prophage fF4 from the F. columnare type strain ATCC 23463, which is not detectable with commonly used prophage search methods. We show that this prophage type has a global distribution and is present in strains isolated from Finland, Thailand, Japan, and North America. The virions of fF4 are myoviruses with contractile tails and infect only bacterial strains originating from Northern Finland. The fF4 resembles transposable phages by similar genome organization and several gene orthologs. Additional bioinformatic analyses reveal several species in the phylum Bacteroidetes that host a similar type of putative prophage, including bacteria that are important animal and human pathogens. Furthermore, a survey of F. columnare Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) spacers indicate a shared evolutionary history between F. columnare strains and the fF4 phage, and another putative prophage in the F. columnare strain ATCC 49512, named p49512. First, CRISPR spacer content from the two CRISPR loci (types II-C and VI-B) of the fF4 lysogen F. columnare ATCC 23463 revealed a phage terminase protein-matching spacer in the VI-B locus. This spacer is also present in two Chinese F. columnare strains. Second, CRISPR analysis revealed four F. columnare strains that contain unique spacers targeting different regions of the putative prophage p49512 in the F. columnare strain ATCC 49512, despite the geographical distance or genomovar of the different strains. This suggests a common ancestry for the F. columnare prophages and different host strains.

scholarly journals Genome Sequence of the Fish Pathogen Flavobacterium columnare ATCC 49512

2012 ◽  
Vol 194 (10) ◽  
pp. 2763-2764 ◽  
Author(s):  
H. C. Tekedar ◽  
A. Karsi ◽  
A. F. Gillaspy ◽  
D. W. Dyer ◽  
N. R. Benton ◽  
...  
Keyword(s):  
Genome Sequence ◽  
Flavobacterium Columnare ◽  
Fish Pathogen

scholarly journals Thermal Tolerance is linked with Virulence in a Fish Pathogen

2017 ◽  
Author(s):  
Roghaieh Ashrafi ◽  
Matthieu Bruneaux ◽  
Lotta-Riina Sundberg ◽  
Katja Pulkkinen ◽  
Janne Valkonen ◽  
...  
Keyword(s):  
Thermal Tolerance ◽  
Virulent Strain ◽  
Flavobacterium Columnare ◽  
Fish Pathogen ◽  
Susceptible Host ◽  
Complex Process ◽  
Evolutionary Changes ◽  
Dependent Change ◽  
Time Dependent Change ◽  
Obligate Pathogen

ABSTRACTAlthough increase in temperatures may boost the number of pathogens, a complex process involving the interaction of a susceptible host, a virulent strain, and environmental factors would influence disease virulence in unpredictable ways. Here we explored if the virulence of an environmentally growing opportunistic fish pathogen,Flavobacterium columnare, would be malleable to evolutionary changes via correlated selection on thermal tolerance. Virulence among the strains increased over years, but tolerance to higher temperatures was associated with reduced virulence. Our results suggest that observed increase in frequency of columnaris epidemics over the last decade is most likely associated with increased length of growing season, or other time dependent change in environment, rather than increased regional average temperatures. Our results also indicate that most virulent bacteria had weaker ability to tolerate outside host environments, which suggest trade-off between more obligate pathogen behaviour and ability to grow outside host.

Emended description and resurrection of Kadsura matsudae (Schisandraceae)

Phytotaxa ◽  
2017 ◽  
Vol 311 (3) ◽  
pp. 255 ◽  
Author(s):  
KENJI SUETSUGU ◽  
TIAN-CHUAN HSU ◽  
TSUGUTAKA TOMA ◽  
TAKASHI MIYAKE ◽  
RICHARD M. K. SAUNDERS
Keyword(s):  
Phylogenetic Analysis ◽  
Distinct Species ◽  
Morphological Characters ◽  
Holotype Specimen ◽  
Sufficient Detail ◽  
Variation Range ◽  
Emended Description ◽  
Typical Variation

The taxonomic identity of Kadsura matsudae is reevaluated. This taxon is often treated as a synonym of K. japonica, a species known from Japan, Korea, and Taiwan. When studying the type materials of K. matsudae, however, we noted that some of its morphological characters, such as the non-contiguous thecae in adjacent stamens, do not fall within the typical variation range of K. japonica. Phylogenetic analysis suggests that although K. matsudae is retrieved within the sect. Kadsura clade, it is not closely related to K. japonica. We therefore propose that K. matsudae should be recognized as a distinct species. Because the protologue of K. matsudae lacks sufficient detail with regards to stamen morphology, which is one of the most important characteristics for identifying the species, we provide an emended description of K. matsudae based on the holotype specimen and newly collected specimens.

scholarly journals Freezing Induces Biased Results in the Molecular Detection of Flavobacterium columnare

2006 ◽  
Vol 72 (2) ◽  
pp. 1702-1704 ◽  
Author(s):  
Lotta-Riina Suomalainen ◽  
Hilkka Reunanen ◽  
Ritva Ijäs ◽  
E. Tellervo Valtonen ◽  
Marja Tiirola
Keyword(s):  
Electron Microscopy ◽  
Molecular Detection ◽  
False Negative ◽  
Infected Fish ◽  
Flavobacterium Columnare ◽  
Fish Pathogen ◽  
Freezing And Thawing ◽  
Negative Results ◽  
Specific Pcr ◽  
False Negative Results

ABSTRACT Specific PCR detection and electron microscopy of Flavobacterium columnare revealed the risk of false-negative results in molecular detection of this fish pathogen. Freezing and thawing destroyed the cells so that DNA was for the most part undetectable by PCR. The detection of bacteria was also weakened after prolonged enrichment cultivation of samples from infected fish.

Sign in / Sign up

Export Citation Format

Share Document