scholarly journals Regulation of OmpA Translation and Shigella dysenteriae Virulence by an RNA Thermometer

2019 ◽  
Vol 88 (3) ◽  
Author(s):  
Erin R. Murphy ◽  
Johanna Roßmanith ◽  
Jacob Sieg ◽  
Megan E. Fris ◽  
Hebaallaha Hussein ◽  
...  
Keyword(s):  
In Silico ◽  
Bacterial Species ◽  
Regulation Of Gene Expression ◽  
Structure And Function ◽  
Shigella Dysenteriae ◽  
Content Type ◽  
Bacterial Physiology ◽  
Wide Range ◽  
Rna Thermometer ◽  
And Function

ABSTRACT RNA thermometers are cis-acting riboregulators that mediate the posttranscriptional regulation of gene expression in response to environmental temperature. Such regulation is conferred by temperature-responsive structural changes within the RNA thermometer that directly result in differential ribosomal binding to the regulated transcript. The significance of RNA thermometers in controlling bacterial physiology and pathogenesis is becoming increasingly clear. This study combines in silico, molecular genetics, and biochemical analyses to characterize both the structure and function of a newly identified RNA thermometer within the ompA transcript of Shigella dysenteriae. First identified by in silico structural predictions, genetic analyses have demonstrated that the ompA RNA thermometer is a functional riboregulator sufficient to confer posttranscriptional temperature-dependent regulation, with optimal expression observed at the host-associated temperature of 37°C. Structural studies and ribosomal binding analyses have revealed both increased exposure of the ribosomal binding site and increased ribosomal binding to the ompA transcript at permissive temperatures. The introduction of site-specific mutations predicted to alter the temperature responsiveness of the ompA RNA thermometer has predictable consequences for both the structure and function of the regulatory element. Finally, in vitro tissue culture-based analyses implicate the ompA RNA thermometer as a bona fide S. dysenteriae virulence factor in this bacterial pathogen. Given that ompA is highly conserved among Gram-negative pathogens, these studies not only provide insight into the significance of riboregulation in controlling Shigella virulence, but they also have the potential to facilitate further understanding of the physiology and/or pathogenesis of a wide range of bacterial species.

Commentary on “Reflections on culture, structure and function of an intensive support service centred on positive behavioural support”

2016 ◽  
Vol 21 (4) ◽  
pp. 212-219 ◽  
Author(s):  
Sandy Toogood
Keyword(s):  
Support Service ◽  
Structure And Function ◽  
Content Type ◽  
Behavioural Support ◽  
Wide Range ◽  
Service Models ◽  
History Of ◽  
Positive Behaviour Support ◽  
The Uk ◽  
And Function

Purpose The purpose of this paper is to provide a commentary on Patterson and Berry’s paper “Reflections on culture, structure and function of an intensive support service centred on positive behavioural support”. Design/methodology/approach This paper reviews key ideas presented in Patterson and Berry’s article relative to the recent history of service delivery in the UK and the growing interest being shown in positive behaviour support. Findings Patterson and Berry’s article adds to a modest literature on specialist support services and should stimulate further descriptions of service models and the concepts underpinning them. Originality/value The literature on specialist support service models is limited and this addition should be relevant to a wide range of clinicians, consumers and commissioners.

Reflections on team culture, structure and function of an intensive support service centred on positive behavioural support

2016 ◽  
Vol 21 (4) ◽  
pp. 203-211 ◽  
Author(s):  
Lawrence A. Patterson ◽  
Samuel Berry
Keyword(s):  
Social Services ◽  
Support Service ◽  
Structure And Function ◽  
Content Type ◽  
Case Examples ◽  
Behavioural Support ◽  
Team Culture ◽  
Shared Identity ◽  
The Right ◽  
And Function

Purpose The purpose of this paper is to explore experiences of team culture, structure and function of an intensive support service (ISS) within the context of the recent service guidance “Building the Right Support” (NHS England, Local Government Association and Association of Directors of Adult Social Services, 2015). Reflections on the Hampshire and Southampton ISS set up in 2010 are discussed with a view to informing a debate about frameworks for ISS services nationally. Design/methodology/approach A reflective piece, drawing on experience and case examples. Findings This paper describes that a key function of an ISS is making individuals safe and this is significantly assisted by using shared team formulation, which can enable information and perspectives to be shared between and within teams as rapidly as possible. Further, a case is made for recognising the importance of inter-disciplinary practice, as the Southampton and Hampshire ISS has removed the “old fashioned” demarcations that led to individuals seeing a “procession” of different professionals from different disciplines. This relates to team structure, but importantly is about a culture of holding a shared identity based on positive behavioural support values, rather than a traditional uni-disciplinary perspective. Practical implications ISS models are being proposed by NHS England and this paper suggests some important practical aspects. Originality/value Limited literature exists examining the team culture within ISSs, which contributes to desired outcomes for service users. This paper opens a debate about structural and functional aspects of service delivery in this service model.

scholarly journals Butyrivibrio hungateiMB2003 Competes Effectively for Soluble Sugars Released byButyrivibrio proteoclasticusB316Tduring Growth on Xylan or Pectin

2018 ◽  
Vol 85 (3) ◽  
Author(s):  
Nikola Palevich ◽  
William J. Kelly ◽  
Siva Ganesh ◽  
Jasna Rakonjac ◽  
Graeme T. Attwood
Keyword(s):  
Bacterial Species ◽  
Soluble Sugars ◽  
Plant Fiber ◽  
Content Type ◽  
Plant Polysaccharide ◽  
Rumen Microbes ◽  
Carbohydrate Degradation ◽  
Wide Range ◽  
Genes Encoding ◽  
Enzymatic Machinery

ABSTRACTRumen bacterial species belonging to the genusButyrivibrioare important degraders of plant polysaccharides, particularly hemicelluloses (arabinoxylans) and pectin. Currently, four species are recognized; they have very similar substrate utilization profiles, but little is known about how these microorganisms are able to coexist in the rumen. To investigate this question,Butyrivibrio hungateiMB2003 andButyrivibrio proteoclasticusB316Twere grown alone or in coculture on xylan or pectin, and their growth, release of sugars, fermentation end products, and transcriptomes were examined. In monocultures, B316Twas able to grow well on xylan and pectin, while MB2003 was unable to utilize either of these insoluble substrates to support significant growth. Cocultures of B316Tgrown with MB2003 revealed that MB2003 showed growth almost equivalent to that of B316Twhen either xylan or pectin was supplied as the substrate. The effect of coculture on the transcriptomes of B316Tand MB2003 was assessed; B316Ttranscription was largely unaffected by the presence of MB2003, but MB2003 expressed a wide range of genes encoding proteins for carbohydrate degradation, central metabolism, oligosaccharide transport, and substrate assimilation, in order to compete with B316Tfor the released sugars. These results suggest that B316Thas a role as an initiator of primary solubilization of xylan and pectin, while MB2003 competes effectively for the released soluble sugars to enable its growth and maintenance in the rumen.IMPORTANCEFeeding a future global population of 9 billion people and climate change are the primary challenges facing agriculture today. Ruminant livestock are important food-producing animals, and maximizing their productivity requires an understanding of their digestive systems and the roles played by rumen microbes in plant polysaccharide degradation.Butyrivibriospecies are a phylogenetically diverse group of bacteria and are commonly found in the rumen, where they are a substantial source of polysaccharide-degrading enzymes for the depolymerization of lignocellulosic material. Our findings suggest that closely related species ofButyrivibriohave developed unique strategies for the degradation of plant fiber and the subsequent assimilation of carbohydrates in order to coexist in the competitive rumen environment. The identification of genes expressed during these competitive interactions gives further insight into the enzymatic machinery used by these bacteria as they degrade the xylan and pectin components of plant fiber.

scholarly journals Structure and function insights garnered from in silico modeling of the thrombospondin type-1 domain-containing 7A antigen

2018 ◽  
Vol 87 (2) ◽  
pp. 136-145 ◽  
Author(s):  
Shana V. Stoddard ◽  
Colin L. Welsh ◽  
Maggie M. Palopoli ◽  
Serena D. Stoddard ◽  
Mounika P. Aramandla ◽  
...  
Keyword(s):  
In Silico ◽  
Structure And Function ◽  
In Silico Modeling ◽  
And Function

In silico study of the structure and function of Streptococcus mutans plasmidic proteins

2017 ◽  
Vol 13 (2) ◽  
Author(s):  
Silvia Caprari ◽  
Giovanni Minervini ◽  
Valentina Brandi ◽  
Fabio Polticelli
Keyword(s):  
Streptococcus Mutans ◽  
In Silico ◽  
Structure And Function ◽  
Positive Bacterium ◽  
Gram Positive ◽  
In Silico Study ◽  
And Function

AbstractThe Gram-positive bacterium

scholarly journals Campylobacter jejuni Triggers Signaling through Host Cell Focal Adhesions To Inhibit Cell Motility

mBio ◽  
2021 ◽  
Author(s):  
Courtney M. Klappenbach ◽  
Nicholas M. Negretti ◽  
Jesse Aaron ◽  
Teng-Leong Chew ◽  
Michael E. Konkel
Keyword(s):  
Epithelial Cells ◽  
Cell Motility ◽  
Host Cell ◽  
Campylobacter Jejuni ◽  
Focal Adhesion ◽  
Foodborne Pathogen ◽  
Focal Adhesions ◽  
Structure And Function ◽  
Content Type ◽  
And Function

Campylobacter jejuni is a major foodborne pathogen that causes severe gastritis. We investigated the dynamics of focal adhesion structure and function in C. jejuni -infected epithelial cells.

scholarly journals Novel deleterious nsSNPs within MEFV gene that could be used as Diagnostic Markers to Predict Hereditary Familial Mediterranean Fever: Using bioinformatics analysis

2018 ◽  
Author(s):  
Mujahed I. Mustafa ◽  
Tebyan A Abdelhameed ◽  
Fatima A. Abdelrhman ◽  
Soada Ahmed Osman ◽  
Mohamed A. Hassan
Keyword(s):  
Familial Mediterranean Fever ◽  
In Silico ◽  
Mediterranean Basin ◽  
Mefv Gene ◽  
Structure And Function ◽  
Diagnostic Markers ◽  
Novel Mutations ◽  
Bioinformatics Tools ◽  
Mediterranean Fever ◽  
And Function

AbstractBackgroundFamilial Mediterranean Fever (FMF) is the most common auto inflammatory disease (AID) affecting mainly the ethnic groups originating from Mediterranean basin, we aimed to identify the pathogenic SNPs in MEFV by computational analysis software.MethodsWe carried out in silico prediction of structural effect of each SNP using different bioinformatics tools to predict substitution influence on protein structure and function.Result23 novel mutations out of 857 nsSNPs that are found to be deleterious effect on the MEFV structure and function.ConclusionThis is the first in silico analysis in MEFV gene to prioritize SNPs for further genetic mapping studies. After using multiple bioinformatics tools to compare and rely on the results predicted, we found 23 novel mutations that may cause FMF disease and it could be used as diagnostic markers for Mediterranean basin populations.

scholarly journals RNA G-Quadruplex Structures Mediate Gene Regulation in Bacteria

mBio ◽  
2020 ◽  
Vol 11 (1) ◽  
Author(s):  
Xiaolong Shao ◽  
Weitong Zhang ◽  
Mubarak Ishaq Umar ◽  
Hei Yuen Wong ◽  
Zijing Seng ◽  
...  
Keyword(s):  
Gene Regulation ◽  
Cell Envelope ◽  
Bacterial Species ◽  
Virulence Gene ◽  
Content Type ◽  
Cellular Processes ◽  
Wide Range ◽  
G Quadruplex ◽  
Eukaryotic Organisms

ABSTRACT Guanine (G)-rich sequences in RNA can fold into diverse RNA G-quadruplex (rG4) structures to mediate various biological functions and cellular processes in eukaryotic organisms. However, the presence, locations, and functions of rG4s in prokaryotes are still elusive. We used QUMA-1, an rG4-specific fluorescent probe, to detect rG4 structures in a wide range of bacterial species both in vitro and in live cells and found rG4 to be an abundant RNA secondary structure across those species. Subsequently, to identify bacterial rG4 sites in the transcriptome, the model Escherichia coli strain and a major human pathogen, Pseudomonas aeruginosa, were subjected to recently developed high-throughput rG4 structure sequencing (rG4-seq). In total, 168 and 161 in vitro rG4 sites were found in E. coli and P. aeruginosa, respectively. Genes carrying these rG4 sites were found to be involved in virulence, gene regulation, cell envelope synthesis, and metabolism. More importantly, biophysical assays revealed the formation of a group of rG4 sites in mRNAs (such as hemL and bswR), and they were functionally validated in cells by genetic (point mutation and lux reporter assays) and phenotypic experiments, providing substantial evidence for the formation and function of rG4s in bacteria. Overall, our study uncovers important regulatory functions of rG4s in bacterial pathogenicity and metabolic pathways and strongly suggests that rG4s exist and can be detected in a wide range of bacterial species. IMPORTANCE G-quadruplex in RNA (rG4) mediates various biological functions and cellular processes in eukaryotic organisms. However, the presence, locations, and functions of rG4 are still elusive in prokaryotes. Here, we found that rG4 is an abundant RNA secondary structure across a wide range of bacterial species. Subsequently, the transcriptome-wide rG4 structure sequencing (rG4-seq) revealed that the model E. coli strain and a major human pathogen, P. aeruginosa, have 168 and 161 in vitro rG4 sites, respectively, involved in virulence, gene regulation, cell envelope, and metabolism. We further verified the regulatory functions of two rG4 sites in bacteria (hemL and bswR). Overall, this finding strongly suggests that rG4s play key regulatory roles in a wide range of bacterial species.

scholarly journals PelX is a UDP-N-acetylglucosamine C4-epimerase involved in Pel polysaccharide–dependent biofilm formation

2020 ◽  
Vol 295 (34) ◽  
pp. 11949-11962 ◽  
Author(s):  
Lindsey S. Marmont ◽  
Gregory B. Whitfield ◽  
Roland Pfoh ◽  
Rohan J. Williams ◽  
Trevor E. Randall ◽  
...  
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Biofilm Formation ◽  
Potential Role ◽  
Bacterial Species ◽  
Gene Clusters ◽  
Structure And Function ◽  
Bacterial Polysaccharide ◽  
H Nmr ◽  
Short Chain Dehydrogenase ◽  
And Function

Pel is a GalNAc-rich bacterial polysaccharide that contributes to the structure and function of Pseudomonas aeruginosa biofilms. The pelABCDEFG operon is highly conserved among diverse bacterial species, and Pel may therefore be a widespread biofilm determinant. Previous annotation of pel gene clusters has helped us identify an additional gene, pelX, that is present adjacent to pelABCDEFG in >100 different bacterial species. The pelX gene is predicted to encode a member of the short-chain dehydrogenase/reductase (SDR) superfamily, but its potential role in Pel-dependent biofilm formation is unknown. Herein, we have used Pseudomonas protegens Pf-5 as a model to elucidate PelX function as Pseudomonas aeruginosa lacks a pelX homologue in its pel gene cluster. We found that P. protegens forms Pel-dependent biofilms; however, despite expression of pelX under these conditions, biofilm formation was unaffected in a ΔpelX strain. This observation led us to identify a pelX paralogue, PFL_5533, which we designate here PgnE, that appears to be functionally redundant to pelX. In line with this, a ΔpelX ΔpgnE double mutant was substantially impaired in its ability to form Pel-dependent biofilms. To understand the molecular basis for this observation, we determined the structure of PelX to 2.1 Å resolution. The structure revealed that PelX resembles UDP-GlcNAc C4-epimerases. Using 1H NMR analysis, we show that PelX catalyzes the epimerization between UDP-GlcNAc and UDP-GalNAc. Our results indicate that Pel-dependent biofilm formation requires a UDP-GlcNAc C4-epimerase that generates the UDP-GalNAc precursors required by the Pel synthase machinery for polymer production.

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