Bent Bacteria: A Comparison of Cell Shape Mechanisms inProteobacteria

2019 ◽  
Vol 73 (1) ◽  
pp. 457-480 ◽  
Author(s):  
Jennifer A. Taylor ◽  
Sophie R. Sichel ◽  
Nina R. Salama
Keyword(s):  
Helicobacter Pylori ◽  
Gastrointestinal Tract ◽  
Phylogenetic Tree ◽  
Vibrio Cholerae ◽  
Campylobacter Jejuni ◽  
Functional Significance ◽  
Cell Shape ◽  
Caulobacter Crescentus ◽  
Selective Pressures

Helical cell shape appears throughout the bacterial phylogenetic tree. Recent exciting work characterizing cell shape mutants in a number of curved and helical Proteobacteria is beginning to suggest possible mechanisms and provide tools to assess functional significance. We focus here on Caulobacter crescentus, Vibrio cholerae, Helicobacter pylori, and Campylobacter jejuni, organisms from three classes of Proteobacteria that live in diverse environments, from freshwater and saltwater to distinct compartments within the gastrointestinal tract of humans and birds. Comparisons among these bacteria reveal common themes as well as unique solutions to the task of maintaining cell curvature. While motility appears to be influenced in all these bacteria when cell shape is perturbed, consequences on niche colonization are diverse, suggesting the need to consider additional selective pressures.

scholarly journals Changes in Nucleoid Morphology and Origin Localization upon Inhibition or Alteration of the Actin Homolog, MreB, of Vibrio cholerae

2007 ◽  
Vol 189 (20) ◽  
pp. 7450-7463 ◽  
Author(s):  
Preeti Srivastava ◽  
Gäelle Demarre ◽  
Tatiana S. Karpova ◽  
James McNally ◽  
Dhruba K. Chattoraj
Keyword(s):  
Escherichia Coli ◽  
Vibrio Cholerae ◽  
Chromosome Segregation ◽  
Cell Shape ◽  
Caulobacter Crescentus ◽  
Wild Type ◽  
E Coli ◽  
The One ◽  
Chromosome Ii ◽  
Chromosome I

ABSTRACT MreB is an actin homolog required for the morphogenesis of most rod-shaped bacteria and for other functions, including chromosome segregation. In Caulobacter crescentus and Escherichia coli, the protein seems to play a role in the segregation of sister origins, but its role in Bacillus subtilis chromosome segregation is less clear. To help clarify its role in segregation, we have here studied the protein in Vibrio cholerae, whose chromosome I segregates like the one in C. crescentus and whose chromosome II like the one in E. coli or B. subtilis. The properties of Vibrio MreB were similar to those of its homologs in other bacteria in that it formed dynamic helical filaments, was essential for viability, and was inhibited by the drug A22. Wild-type (WT) cells exposed to A22 became spherical and larger. The nucleoids enlarged correspondingly, and the origin positions for both the chromosomes no longer followed any fixed pattern. However, the sister origins separated, unlike the situation in other bacteria. In mutants isolated as A22 resistant, the nucleoids in some cases appeared compacted even when the cell shape was nearly normal. In these cells, the origins of chromosome I were at the distal edges of the nucleoid but not all the way to the poles where they normally reside. The sister origins of chromosome II also separated less. Thus, it appears that the inhibition or alteration of Vibrio MreB can affect both the nucleoid morphology and origin localization.

Investigations into the antibacterial activities of herbal medicines against Helicobacter pylori and Campylobacter jejuni

Planta Medica ◽  
2008 ◽  
Vol 74 (09) ◽  
Author(s):  
C Cwikla ◽  
K Schmidt ◽  
A Matthias ◽  
KM Bone ◽  
RP Lehmann ◽  
...  
Keyword(s):  
Helicobacter Pylori ◽  
Campylobacter Jejuni ◽  
Herbal Medicines ◽  
Antibacterial Activities

A Population-Based Survey on Gastrointestinal Tract Symptoms and Helicobacter pylori Infection in Children and Adolescents

Helicobacter ◽  
2002 ◽  
Vol 7 (6) ◽  
pp. 356-363 ◽  
Author(s):  
Costantino De Giacomo ◽  
Valeria Valdambrini ◽  
Francesca Lizzoli ◽  
Anna Gissi ◽  
Marina Palestra ◽  
...  
Keyword(s):  
Helicobacter Pylori ◽  
Gastrointestinal Tract ◽  
Children And Adolescents ◽  
Population Based ◽  
Helicobacter Pylori Infection ◽  
Population Based Survey

scholarly journals Effect of Helicobacter pylori infection on the link between GLP-1 expression and motility of the gastrointestinal tract

PLoS ONE ◽  
2017 ◽  
Vol 12 (5) ◽  
pp. e0177232 ◽  
Author(s):  
Hirotsugu Eda ◽  
Hirokazu Fukui ◽  
Ryosuke Uchiyama ◽  
Yoshitaka Kitayama ◽  
Ken Hara ◽  
...  
Keyword(s):  
Helicobacter Pylori ◽  
Gastrointestinal Tract ◽  
Helicobacter Pylori Infection

Histopathological study of gastrointestinal endoscopic biopsies in pediatric patients

QJM ◽  
2021 ◽  
Vol 114 (Supplement_1) ◽  
Author(s):  
Faten A Ghazal ◽  
Wesam M Osman ◽  
Sarah A Hakim ◽  
Nada N Tamem
Keyword(s):  
Inflammatory Bowel Disease ◽  
Helicobacter Pylori ◽  
Celiac Disease ◽  
Gastrointestinal Tract ◽  
Gastrointestinal Diseases ◽  
University Hospital ◽  
Gastrointestinal Lesions ◽  
Different Types ◽  
Inflammatory Bowel ◽  
Gastrointestinal Inflammation

Abstract Background Non neoplastic GI lesions in pediatrics are variable and differ in types and prevalence among each pediatric age group. Helicobacter pylori is an important pathogen that can cause gastritis and peptic ulcers in adults as well as in children. Celiac disease is a gluten-dependent autoimmune disorder which affects individuals having genetic susceptibility. Eosinophilic gastrointestinal diseases are disorders that primarily affect the gastrointestinal tract with eosinophil-rich inflammation in the absence of known causes for eosinophilia. Inflammatory bowel disease (IBD) is a chronic inflammatory disorder, mainly affecting the gastrointestinal tract with extraintestinal manifestations and associated immune disorders. It seems that it is one of the most common gastrointestinal diseases affecting children in the developed countries. Aim of the work To study different types of paediatric non neoplastic gastrointestinal lesions from gastrointestinal endoscopic biopsies received at the Pathology Department in Ain Shams University hospital during a period of 2 years (2017-2018), and to correlate them with the clinicopathological presentations and endoscopic findings. Patients and Methods A cross sectional study was conducted on all pediatric gastrointestinal biopsies received at Pathology Department in Ain Shams University Hospital during the period of two years (2017- 2018). Only cases with information for all the covariates (n = 580) were selected and the results were statistically analyzed. Results Total 580 pediatric cases were enrolled according to inclusion criteria. Nonspecific gastrointestinal inflammation represented (47.1%), Helicobacter pylori associated gastrointestinal inflammation represented (43.5%), Eosinophilic gastrointestinal disease represented (3.8%), Inflammatory bowel disease (IBD) represented (3.7%), Celiac disease represented (1.9%). Conclusion This is the first study conducted in Ain Shams University Hospitals to assess the different types of pediatric non neoplastic gastrointestinal lesions received with clinicopathological and endoscopic correlation. The most common pediatric non neoplastic GI lesion is Helicobacter pylori infection. The diagnosis of pediatric non neoplastic GI disorder necessitates interdepartmental teamwork between GI pediatricians and pathologists.

scholarly journals How (and why) fins turn into limbs: insights from anglerfish

2018 ◽  
Vol 109 (1-2) ◽  
pp. 87-103 ◽  
Author(s):  
Blake V. DICKSON ◽  
Stephanie E. PIERCE
Keyword(s):  
Deep Sea ◽  
Functional Significance ◽  
Vertebrate Evolution ◽  
Underlying Structure ◽  
Pectoral Fin ◽  
Anatomical Features ◽  
Pectoral Fins ◽  
Selective Pressures ◽  
Musculoskeletal Anatomy

ABSTRACTThe fin-to-limb transition is heralded as one of the most important events in vertebrate evolution. Over the last few decades our understanding of how limbs evolved has significantly increased; but, hypotheses for why limbs evolved are still rather open. Fishes that engage their fins to ‘walk' along substrate may provide some perspective. The charismatic frogfishes are often considered to have the most limb-like fins, yet we still know little about their underlying structure. Here we reconstruct the pectoral fin musculoskeletal anatomy of the scarlet frogfish to identify adaptations that support fin-assisted walking behaviours. The data are compared to three additional anglerfish species: the oval batfish, which represents an independent acquisition of fin-assisted walking; and two pelagic deep-sea swimmers, the triplewart seadevil and ghostly seadevil. Our results clearly show broad musculoskeletal differences between the pectoral fins of swimming and walking anglerfish species. The frogfish and batfish have longer and more robust fins; larger, differentiated muscles; and better developed joints, including a reverse ball-and-socket glenoid joint and mobile ‘wrist'. Further, the frogfish and batfish show finer-scale musculoskeletal differences that align with their specific locomotor ecologies. Within, we discuss the functional significance of these anatomical features in relation to walking, the recurring evolution of similar adaptations in other substrate locomoting fishes, as well as the selective pressures that may underlie the evolution of limbs.

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