0054 - The effect of sub-lethal levels of the Roseobacter secondary metabolite, tropodithietic acid, on gene expression of Vibrio vulnificus

2018 ◽  
Author(s):  
Karen Kiesbye Dittmann ◽  
Josefine Hansen
Keyword(s):  
Gene Expression ◽  
Secondary Metabolite ◽  
Vibrio Vulnificus ◽  
Tropodithietic Acid

scholarly journals Positive Regulation of fur Gene Expression via Direct Interaction of Fur in a Pathogenic Bacterium, Vibrio vulnificus

2007 ◽  
Vol 189 (7) ◽  
pp. 2629-2636 ◽  
Author(s):  
Hyun-Jung Lee ◽  
So Hyun Bang ◽  
Kyu-Ho Lee ◽  
Soon-Jung Park
Keyword(s):  
Gene Expression ◽  
Pathogenic Bacteria ◽  
Vibrio Vulnificus ◽  
Iron Concentration ◽  
Direct Interaction ◽  
Repeated Sequence ◽  
Upstream Region ◽  
Fur Protein

ABSTRACT In pathogenic bacteria, the ability to acquire iron, which is mainly regulated by the ferric uptake regulator (Fur), is essential to maintain growth as well as its virulence. In Vibrio vulnificus, a human pathogen causing gastroenteritis and septicemia, fur gene expression is positively regulated by Fur when the iron concentration is limited (H.-J. Lee et al., J. Bacteriol. 185:5891-5896, 2003). Footprinting analysis revealed that an upstream region of the fur gene was protected by the Fur protein from DNase I under iron-depleted conditions. The protected region, from −142 to −106 relative to the transcription start site of the fur gene, contains distinct AT-rich repeats. Mutagenesis of this repeated sequence resulted in abolishment of binding by Fur. To confirm the role of this cis-acting element in Fur-mediated control of its own gene in vivo, fur expression was monitored in V. vulnificus strains using a transcriptional fusion containing the mutagenized Fur-binding site (fur mt::luxAB). Expression of fur mt::luxAB showed that it was not regulated by Fur and was not influenced by iron concentration. Therefore, this study demonstrates that V. vulnificus Fur acts as a positive regulator under iron-limited conditions by direct interaction with the fur upstream region.

scholarly journals Rice-induced secondary metabolite gene expression in Aspergillus nidulans

2020 ◽  
Vol 47 (12) ◽  
pp. 1109-1116
Author(s):  
Christopher J. Lacriola ◽  
Shaun P. Falk ◽  
Bernard Weisblum
Keyword(s):  
Gene Expression ◽  
Aspergillus Nidulans ◽  
Secondary Metabolite

scholarly journals Production of the Antimicrobial Secondary Metabolite Indigoidine Contributes to Competitive Surface Colonization by the Marine Roseobacter Phaeobacter sp. Strain Y4I

2012 ◽  
Vol 78 (14) ◽  
pp. 4771-4780 ◽  
Author(s):  
W. Nathan Cude ◽  
Jason Mooney ◽  
Arash A. Tavanaei ◽  
Mary K. Hadden ◽  
Ashley M. Frank ◽  
...  
Keyword(s):  
Gene Expression ◽  
Secondary Metabolite ◽  
Biosynthetic Pathway ◽  
Wild Type Strain ◽  
Vibrio Fischeri ◽  
Random Mutagenesis ◽  
Blue Pigment ◽  
Wild Type ◽  
Content Type ◽  
Artificial Surface

ABSTRACTMembers of theRoseobacterlineage of marine bacteria are prolific surface colonizers in marine coastal environments, and antimicrobial secondary metabolite production has been hypothesized to provide a competitive advantage to colonizing roseobacters. Here, we report that the roseobacterPhaeobactersp. strain Y4I produces the blue pigment indigoidine via a nonribosomal peptide synthase (NRPS)-based biosynthetic pathway encoded by a novel series of genetically linked genes:igiBCDFE. A Tn5-based random mutagenesis library of Y4I showed a perfect correlation between indigoidine production by thePhaeobacterstrain and inhibition ofVibrio fischerion agar plates, revealing a previously unrecognized bioactivity of this molecule. In addition, igiD null mutants (igiD encoding the indigoidine NRPS) were more resistant to hydrogen peroxide, less motile, and faster to colonize an artificial surface than the wild-type strain. Collectively, these data provide evidence for pleiotropic effects of indigoidine production in this strain. Gene expression assays support phenotypic observations and demonstrate thatigiDgene expression is upregulated during growth on surfaces. Furthermore, competitive cocultures ofV. fischeriand Y4I show that the production of indigoidine by Y4I significantly inhibits colonization ofV. fischerion surfaces. This study is the first to characterize a secondary metabolite produced by an NRPS in roseobacters.

scholarly journals PVv3, a New Shuttle Vector for Gene Expression in Vibrio vulnificus

2013 ◽  
Vol 80 (4) ◽  
pp. 1477-1481 ◽  
Author(s):  
Karina Klevanskaa ◽  
Nadja Bier ◽  
Kerstin Stingl ◽  
Eckhard Strauch ◽  
Stefan Hertwig
Keyword(s):  
Gene Expression ◽  
Escherichia Coli ◽  
Green Fluorescent Protein ◽  
Vibrio Parahaemolyticus ◽  
Fluorescent Protein ◽  
Vibrio Vulnificus ◽  
Shuttle Vector ◽  
Content Type ◽  
E Coli ◽  
Green Fluorescent

ABSTRACTAn efficient electroporation procedure forVibrio vulnificuswas designed using the new cloning vector pVv3 (3,107 bp). Transformation efficiencies up to 2 × 106transformants per μg DNA were achieved. The vector stably replicated in bothV. vulnificusandEscherichia coliand was also successfully introduced intoVibrio parahaemolyticusandVibrio cholerae. To demonstrate the suitability of the vector for molecular cloning, the green fluorescent protein (GFP) gene and thevvhBAhemolysin operon were inserted into the vector and functionally expressed inVibrioandE. coli.

scholarly journals Expression of Tropodithietic Acid Biosynthesis Is Controlled by a Novel Autoinducer

2010 ◽  
Vol 192 (17) ◽  
pp. 4377-4387 ◽  
Author(s):  
Haifeng Geng ◽  
Robert Belas
Keyword(s):  
Gene Expression ◽  
Biologically Active ◽  
Biogeochemical Processes ◽  
Wild Type ◽  
Acid Biosynthesis ◽  
Transcriptional Fusion ◽  
Tropodithietic Acid ◽  
Eukaryotic Microorganisms ◽  
Close Proximity ◽  
Liquid Culturing

ABSTRACT The interactions between marine prokaryotic and eukaryotic microorganisms are crucial to many biological and biogeochemical processes in the oceans. Often the interactions are mutualistic, as in the symbiosis between phytoplankton, e.g., the dinoflagellate Pfiesteria piscicida and Silicibacter sp. TM1040, a member of the Roseobacter taxonomic lineage. It is hypothesized that an important component of this symbiosis is bacterial production of tropodithietic acid (TDA), a biologically active tropolone compound whose synthesis requires the expression of tda ABCDEF (tdaA-F), as well as six additional genes (cysI, malY, paaIJK, and tdaH). The factors controlling tda gene expression are not known, although growth in laboratory standing liquid cultures drastically increases TDA levels. In this report, we measured the transcription of tda genes to gain a greater understanding of the factors controlling their expression. While the expression of tdaAB was constitutive, tdaCDE and tdaF mRNA increased significantly (3.7- and 17.4-fold, respectively) when cells were grown in standing liquid broth compared to their levels with shaking liquid culturing. No transcription of tdaC was detected when a tdaC p::lacZ transcriptional fusion was placed in 11 of the 12 Tda− mutant backgrounds, with cysI being the sole exception. The expression of tdaC could be restored to 9 of the remaining 11 Tda− mutants—tdaA and tdaH failed to respond—by placing wild-type (Tda+) strains in close proximity or by supplying exogenous TDA to the mutant, suggesting that TDA induces tda gene expression. These results indicate that TDA acts as an autoinducer of its own synthesis and suggest that roseobacters may use TDA as a quorum signal.

scholarly journals Changes of global gene expression and secondary metabolite accumulation during light-dependent Aspergillus nidulans development

2016 ◽  
Vol 87 ◽  
pp. 30-53 ◽  
Author(s):  
Özgür Bayram ◽  
Kirstin Feussner ◽  
Marc Dumkow ◽  
Cornelia Herrfurth ◽  
Ivo Feussner ◽  
...  
Keyword(s):  
Gene Expression ◽  
Aspergillus Nidulans ◽  
Secondary Metabolite ◽  
Global Gene Expression ◽  
Metabolite Accumulation
Sign in / Sign up

Export Citation Format

Share Document