A rapid method for the detection of motility in Acinetobacter baumannii and its association to the existence of the virulence-associated genes pilA and algW

2021 ◽  
Vol 1 (3) ◽  
pp. 11-17
Author(s):  
Gamal Wareth ◽  
Mathias W. Pletz ◽  
Heinrich Neubauer ◽  
Lisa D. Sprague
Keyword(s):  
Urinary Tract ◽  
Soft Tissue ◽  
Rapid Detection ◽  
Phenotypic Characterization ◽  
Wound Infections ◽  
Nosocomial Pathogen ◽  
Genes Encoding ◽  
Pila Gene ◽  
Fimbrial Protein

Acinetobacter (A.) baumannii is one of the major nosocomial pathogens worldwide. It is associated with bloodstream infection, pneumonia, meningitis, urinary tract, soft tissue, and wound infections. Several factors contribute to its survival and spread as a nosocomial pathogen, and motility is often associated with the virulence, fitness, and tenacity of A. baumannii on surfaces. In the present study, the correlation between the presence of genes encoding for fimbrial protein PilA and periplasmic protease AlgW and motility was investigated in 87 clinical and non-clinical A. baumannii isolates from Germany. A. baumannii exhibited robust swimming, swarming, and twitching movement based on the percentage of agar in the medium, as well as the time and temperature of incubation. The swarm motility medium utilizing 2% agar with tetrazolium salts provided an efficient assay for the phenotypic characterization of A. baumannii and it was more efficient than the classical motility assays in terms of time, visibility, and biosafety. The presence of the pilA gene increased motility of A. baumannii but was not required for motility. The algW gene was found in 18 strains obtained from milk, all of them with proven phenotypic motility. The rapid detection of motility is essential to evaluate the virulence and fitness of A. baumannii. Further studies on the level of genome, transcriptome and proteome are needed to investigate the secrets behind different movement paths in each strain.

Genotypic and phenotypic characterization of Pseudomonas aeruginosa isolates from urinary tract infections

2011 ◽  
Vol 301 (4) ◽  
pp. 282-292 ◽  
Author(s):  
Petra Tielen ◽  
Maike Narten ◽  
Nathalie Rosin ◽  
Ilona Biegler ◽  
Isam Haddad ◽  
...  
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Urinary Tract ◽  
Urinary Tract Infections ◽  
Phenotypic Characterization ◽  
Tract Infections

Drosophila brachyenteron regulates gene activity and morphogenesis in the gut

Development ◽  
1996 ◽  
Vol 122 (12) ◽  
pp. 3707-3718 ◽  
Author(s):  
J.B. Singer ◽  
R. Harbecke ◽  
T. Kusch ◽  
R. Reuter ◽  
J.A. Lengyel
Keyword(s):  
Genetic Locus ◽  
Malpighian Tubules ◽  
Gene Activity ◽  
Phenotypic Characterization ◽  
Gut Development ◽  
Allelic Series ◽  
Genes Encoding

Chromosomal region 68D/E is required for various aspects of Drosophila gut development; within this region maps the Brachyury homolog T-related gene (Trg), DNA of which rescues the hindgut defects of deficiency 68D/E. From a screen of 13,000 mutagenized chromosomes we identified six non-complementing alleles that are lethal over deficiencies of 68D/E and show a hindgut phenotype. These mutations constitute an allelic series and are all rescued to viability by a Trg transgene. We have named the mutant alleles and the genetic locus they define brachyenteron (byn); phenotypic characterization of the strongest alleles allows determination of the role of byn in embryogenesis. byn expression is activated by tailless, but byn does not regulate itself. byn expression in the hindgut and anal pad primordia is required for the regulation of genes encoding transcription factors (even-skipped, engrailed, caudal, AbdominalB and orthopedia) and cell signaling molecules (wingless and decapentaplegic). In byn mutant embryos, the defective program of gene activity in these primordia is followed by apoptosis (initiated by reaper expression and completed by macrophage engulfment), resulting in severely reduced hindgut and anal pads. Although byn is not expressed in the midgut or the Malpighian tubules, it is required for the formation of midgut constrictions and for the elongation of the Malpighian tubules.

Genetic Interactions between the Coagulation and Fibrinolytic Systems

2001 ◽  
Vol 86 (07) ◽  
pp. 130-137 ◽  
Author(s):  
Jay Degen
Keyword(s):  
Associated Factors ◽  
Genetic Interactions ◽  
Phenotypic Characterization ◽  
System Components ◽  
Genes Encoding ◽  
Hemostatic Factors ◽  
Mouse Lines ◽  
Made In

SummaryNearly all of the genes encoding the established coagulation and fibrinolytic factors have been successfully altered or disrupted in transgenic mice. Although comprehensive studies of each of these genetargeted mouse lines are still ongoing, the initial findings have significantly refined our understanding of the roles of selected hemostatic factors in vivo, and occasionally altered long-standing concepts. This review summarizes some of the progress that has been made in the generation and phenotypic characterization of mice lacking key hemostatic factors, including coagulation, fibrinolytic, platelet and endothelial cell-associated factors. New insights regarding the role(s) and interplay of hemostatic factors that have emerged from detailed studies of mice carrying multiple deficits in coagulation and fibrinolytic system components are highlighted.

scholarly journals Trans -cinnamaldehyde attenuates Enterococcus faecalis virulence and inhibits biofilm formation

2021 ◽  
Author(s):  
Islam A.A Ali ◽  
Jukka Matinlinna ◽  
Celine Lévesque ◽  
Prasanna Neelakantan
Keyword(s):  
Gene Regulation ◽  
Urinary Tract ◽  
Enterococcus Faecalis ◽  
Biofilm Formation ◽  
Host Tissue ◽  
Wound Infections ◽  
Mechanistic Studies ◽  
Surgical Wound ◽  
Nosocomial Pathogen ◽  
Wide Range

Enterococcus faecalis  as an important nosocomial pathogen is critically implicated in the pathogenesis of endocarditis, urinary tract and surgical wound infections. Its major virulence attributes (biofilm formation, production of proteases and hemolytic toxins) enable it to cause extensive host tissue damage. With the alarming increase in enterococcal resistance to antibiotics, novel therapeutics are required to inhibit  E. faecalis  biofilm formation and virulence.  Trans -cinnamaldehyde (TC), the main phytochemical in cinnamon essential oils has demonstrated promising activity against a wide range of pathogens. Here, we comprehensively investigated the effect of TC on planktonic growth, biofilm formation, proteolytic and hemolytic activities, as well as gene regulation in  E. faecalis . Our findings revealed that sub-inhibitory concentrations of TC reduced biofilm formation, biofilm exopolysaccharides as well as its proteolytic and hemolytic activities. Mechanistic studies revealed significant down regulation of the quorum sensing  fsr  locus and downstream  gelE , which are major virulence regulators in  E. faecalis . Taken together, our study highlights the potential of TC to inhibit  E. faecalis biofilm formation and its virulence.

Transgenic animals modelling polyamine metabolism-related diseases

2009 ◽  
Vol 46 ◽  
pp. 125-144 ◽  
Author(s):  
Leena Alhonen ◽  
Anne Uimari ◽  
Marko Pietilä ◽  
Mervi T. Hyvönen ◽  
Eija Pirinen ◽  
...  
Keyword(s):  
Transgenic Mice ◽  
Transgenic Animals ◽  
Polyamine Metabolism ◽  
Phenotypic Characterization ◽  
Previous Knowledge ◽  
Adenosylmethionine Decarboxylase ◽  
Genes Encoding ◽  
Metabolic Cycle

Cloning of genes related to polyamine metabolism has enabled the generation of genetically modified mice and rats overproducing or devoid of proteins encoded by these genes. Our first transgenic mice overexpressing ODC (ornithine decarboxylase) were generated in 1991 and, thereafter, most genes involved in polyamine metabolism have been used for overproduction of the respective proteins, either ubiquitously or in a tissue-specific fashion in transgenic animals. Phenotypic characterization of these animals has revealed a multitude of changes, many of which could not have been predicted based on the previous knowledge of the polyamine requirements and functions. Animals that overexpress the genes encoding the inducible key enzymes of biosynthesis and catabolism, ODC and SSAT (spermidine/spermine N1-acetyltransferase) respectively, appear to possess the most pleiotropic phenotypes. Mice overexpressing ODC have particularly been used as cancer research models. Transgenic mice and rats with enhanced polyamine catabolism have revealed an association of rapidly depleted polyamine pools and accelerated metabolic cycle with development of acute pancreatitis and a fatless phenotype respectively. The latter phenotype with improved glucose tolerance and insulin sensitivity is useful in uncovering the mechanisms that lead to the opposite phenotype in humans, Type 2 diabetes. Disruption of the ODC or AdoMetDC [AdoMet (S-adenosylmethionine) decarboxylase] gene is not compatible with mouse embryogenesis, whereas mice with a disrupted SSAT gene are viable and show no harmful phenotypic changes, except insulin resistance at a late age. Ultimately, the mice with genetically altered polyamine metabolism can be used to develop targeted means to treat human disease conditions that they relevantly model.

scholarly journals Genotypic and Phenotypic Characterization of Streptomyces Species Causing Potato Common Scab in Uruguay

Plant Disease ◽  
2017 ◽  
Vol 101 (8) ◽  
pp. 1362-1372 ◽  
Author(s):  
M. I. Lapaz ◽  
J. C. Huguet-Tapia ◽  
M. I. Siri ◽  
E. Verdier ◽  
R. Loria ◽  
...  
Keyword(s):  
Common Scab ◽  
Economic Losses ◽  
Phenotypic Characterization ◽  
Marker Genes ◽  
Streptomyces Species ◽  
Streptomyces Spp ◽  
Isolation And Characterization ◽  
Potato Common Scab ◽  
Genes Encoding

Isolation and characterization of common scab (CS) pathogen Streptomyces spp. from Uruguayan potato tubers and soil samples were done in response to significant economic losses due to CS on potato in autumn 2010. Seventy of the 331 isolates were classified as pathogenic owing to their ability to induce necrosis on tuber disks and stunting of radish seedling. Streptomyces spp. causing CS on potato in Uruguay were found to represent a range of different species by virtue of their diverse morphological and physiological traits as well as rep-PCR, rpoB phylogenetic analysis, and multi-locus sequences analysis. We identified isolates primarily as Streptomyces scabiei, S. acidiscabies, and S. europaeiscabiei. However, some of the pathogenic isolates still remain to be identified at the species level. This highlights the need for improved methods for discrimination among pathogenic Streptomyces species. The presence of Streptomyces pathogenicity island (PAI) genes was analyzed, including genes encoding for thaxtomin synthetase (txtA, txtB), tomatinase (tomA), and a necrosis protein (nec1). Among the isolates that were pathogenic, 50% contained the four pathogenicity genes, 33% had an atypical composition of PAI marker genes, and 17% did not contain any genes. The absence of the genes reported to be involved in thaxtomin biosynthesis (txtA, txtB) was confirmed by whole-genome sequencing of two representative strains of this group. This finding suggests the participation of other virulence factors in plant pathogenicity.

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