Identification and characterization of FtsH mediating in vivo colonization and stress adaptation in the fish pathogen Edwardsiella piscicida

2019 ◽  
Vol 366 (16) ◽  
Author(s):  
Ruiqing Ma ◽  
Jianchang Huang ◽  
Yuanxing Zhang ◽  
Qiyao Wang
Keyword(s):  
Pattern Analysis ◽  
Enteric Bacteria ◽  
Prolonged Treatment ◽  
Protein Homeostasis ◽  
Enteric Bacterium ◽  
Fish Pathogen ◽  
Edwardsiella Piscicida ◽  
Identification And Characterization

ABSTRACT Edwardsiella piscicida is an important pathogenic enteric bacterium of fish. FtsH is a unique membrane-anchored AAA + protease that regulates protein homeostasis in bacteria. In cooperation with modulators HflK and HflC, FtsH is essential in enteric bacteria and controls the response to environmental stresses. Here, we used in vivo pattern analysis of conditional essentiality (PACE) and identified that ftsH and hflK/C were associated with impaired in vivo colonization in Edw. piscicida and attenuated internalization ability of ZF4 cells. The ftsH mutant displayed increased survival during prolonged treatment of starvation and high osmotic stresses in Edw. piscicida. Further analysis showed that the disruption of ftsH resulted in the overproduction of the established substrate LpxC, which is responsible for the synthesis of LPS (lipopolysaccharide), as well as the substrate YfgM, which is involved in high osmolality tolerance during stationary phase. However, the inconsistency in the abilities of the ftsH and hflK/C mutants to achieve YfgM-based osmotic resistance indicated that there might be multiple, while distinctive, pathways controlled by FtsH and the associated modulator proteins HflK/C. This investigation revealed the unique functions of FtsH and its modulator HflK/C in Edw. piscicida.

scholarly journals Time-Resolved Transposon Insertion Sequencing Reveals Genome-Wide Fitness Dynamics during Infection

mBio ◽  
2017 ◽  
Vol 8 (5) ◽  
Author(s):  
Guanhua Yang ◽  
Gabriel Billings ◽  
Troy P. Hubbard ◽  
Joseph S. Park ◽  
Ka Yin Leung ◽  
...  
Keyword(s):  
Time Series ◽  
Pattern Analysis ◽  
Sampling Point ◽  
Fish Pathogen ◽  
Vaccine Candidates ◽  
Transposon Insertion ◽  
Genome Wide ◽  
Edwardsiella Piscicida ◽  
Transposon Insertion Sequencing

ABSTRACT Transposon insertion sequencing (TIS) is a powerful high-throughput genetic technique that is transforming functional genomics in prokaryotes, because it enables genome-wide mapping of the determinants of fitness. However, current approaches for analyzing TIS data assume that selective pressures are constant over time and thus do not yield information regarding changes in the genetic requirements for growth in dynamic environments (e.g., during infection). Here, we describe structured analysis of TIS data collected as a time series, termed pattern analysis of conditional essentiality (PACE). From a temporal series of TIS data, PACE derives a quantitative assessment of each mutant’s fitness over the course of an experiment and identifies mutants with related fitness profiles. In so doing, PACE circumvents major limitations of existing methodologies, specifically the need for artificial effect size thresholds and enumeration of bacterial population expansion. We used PACE to analyze TIS samples of Edwardsiella piscicida (a fish pathogen) collected over a 2-week infection period from a natural host (the flatfish turbot). PACE uncovered more genes that affect E. piscicida ’s fitness in vivo than were detected using a cutoff at a terminal sampling point, and it identified subpopulations of mutants with distinct fitness profiles, one of which informed the design of new live vaccine candidates. Overall, PACE enables efficient mining of time series TIS data and enhances the power and sensitivity of TIS-based analyses. IMPORTANCE Transposon insertion sequencing (TIS) enables genome-wide mapping of the genetic determinants of fitness, typically based on observations at a single sampling point. Here, we move beyond analysis of endpoint TIS data to create a framework for analysis of time series TIS data, termed pattern analysis of conditional essentiality (PACE). We applied PACE to identify genes that contribute to colonization of a natural host by the fish pathogen Edwardsiella piscicida. PACE uncovered more genes that affect E. piscicida ’s fitness in vivo than were detected using a terminal sampling point, and its clustering of mutants with related fitness profiles informed design of new live vaccine candidates. PACE yields insights into patterns of fitness dynamics and circumvents major limitations of existing methodologies. Finally, the PACE method should be applicable to additional “omic” time series data, including screens based on clustered regularly interspaced short palindromic repeats with Cas9 (CRISPR/Cas9).

scholarly journals The thermostable 4,6-α-glucanotransferase of Bacillus coagulans DSM 1 synthesizes isomaltooligosaccharides

Amylase ◽  
2021 ◽  
Vol 5 (1) ◽  
pp. 13-22
Author(s):  
Gang Xiang ◽  
Piet L. Buwalda ◽  
Marc J.E.C van der Maarel ◽  
Hans Leemhuis
Keyword(s):  
Bacillus Coagulans ◽  
Glycoside Hydrolase Family ◽  
Rat Intestine ◽  
Glycaemic Response ◽  
Food Ingredient ◽  
Starch Conversion ◽  
Identification And Characterization ◽  
Hydrolase Family

Abstract The 4,6-α-glucanotransferases of the glycoside hydrolase family 70 can convert starch into isomaltooligosaccharides (IMOs). However, no thermostable 4,6-α-glucanotransferases have been reported to date, limiting their applicability in the starch conversion industry. Here we report the identification and characterization of a thermostable 4,6-α-glucanotransferase from Bacillus coagulans DSM 1. The gene was cloned and the recombinant protein, called BcGtfC, was produced in Escherichia coli. BcGtfC is stable up to 66 °C in the presence of substrate. It converts debranched starch into an IMO product with a high percentage of α-1,6-glycosidic linkages and a relatively high molecular weight compared to commercially available IMOs. Importantly, the product is only partly and very slowly digested by rat intestine powder, suggesting that the IMO will provide a low glycaemic response in vivo when applied as food ingredient. Thus, BcGtfC is a thermostable 4,6-α-glucanotransferase suitable for the industrial production of slowly digestible IMOs from starch.

scholarly journals Isolation and characterization of escherichia coli in ready-to-eat foods vended in Islamic University, Kushtia

1970 ◽  
Vol 18 ◽  
pp. 99-103 ◽  
Author(s):  
S Biswas ◽  
MAK Parvez ◽  
M Shafiquzzaman ◽  
S Nahar ◽  
MN Rahman
Keyword(s):  
Escherichia Coli ◽  
Pattern Analysis ◽  
University Campus ◽  
Rflp Pattern ◽  
E Coli ◽  
Fish Meat ◽  
Isolation And Characterization ◽  
Food Borne ◽  
Identification And Characterization

Context: Escherichia coli is shed in the feces of warm blooded animals and humans and thus potential for public health. Detection and characterization of E. coli in the ready-to-eat (RTE) foods concerns due to their presence indicates fecal contamination of the food.   Objective: To identify, characterize and RFLP pattern analysis of E. coli isolated from RTE foods vended in Islamic University campus, Kushtia.   Materials and Methods: Fifty samples from four types of consumed foods in six student halls of residence, some temporary restaurants of Islamic University, Kushtia were assessed for bacterial contamination by standard methods. Identification and characterization of E. coli isolates were performed using IMViC tests. Genomic DNA was used to perform RFLP pattern analysis.   Results: Thirty seven out of 50 (74%) examined samples of RTE foods had E. coli contamination. The highest number of E. coli was isolated from vegetable oriented RTE foods (90.90%) and fish, meat and cereals samples were also significantly E. coli positive. RFLP profiling of two E. coli isolates were observed.   Conclusion: The results of this study provide evidence that some RTE foods had unsatisfactory levels of contamination with E. coli. Thus street vended RTE food could be important potential vehicles for food-borne diseases. Molecular characterization may be exploited to identify food borne pathogen among different species.  Keywords: Ready-to-eat foods; Escherichia coli; RFLP pattern DOI: http://dx.doi.org/10.3329/jbs.v18i0.8783 JBS 2010; 18(0): 99-103

scholarly journals Investigating the RAS can be a fishy business: interdisciplinary opportunities using Zebrafish

2018 ◽  
Vol 132 (23) ◽  
pp. 2469-2481 ◽  
Author(s):  
Scott Hoffmann ◽  
Linda Mullins ◽  
Charlotte Buckley ◽  
Sebastien Rider ◽  
John Mullins
Keyword(s):  
Imaging Techniques ◽  
Renin Angiotensin System ◽  
Angiotensin System ◽  
Cell Ablation ◽  
Ras Inhibition ◽  
Zebrafish Pronephros ◽  
Identification And Characterization ◽  
Structural Simplicity

The renin–angiotensin system (RAS) is highly conserved, and components of the RAS are present in all vertebrates to some degree. Although the RAS has been studied since the discovery of renin, its biological role continues to broaden with the identification and characterization of new peptides. The evolutionarily distant zebrafish is a remarkable model for studying the kidney due to its genetic tractability and accessibility for in vivo imaging. The zebrafish pronephros is an especially useful kidney model due to its structural simplicity yet complex functionality, including capacity for glomerular and tubular filtration. Both the pronephros and mesonephros contain renin-expressing perivascular cells, which respond to RAS inhibition, making the zebrafish an excellent model for studying the RAS. This review summarizes the physiological and genetic tools currently available for studying the zebrafish kidney with regards to functionality of the RAS, using novel imaging techniques such as SPIM microscopy coupled with targeted single cell ablation and synthesis of vasoactive RAS peptides.

Characterization of the Japanese flounder NLRP3 inflammasome in restricting Edwardsiella piscicida colonization in vivo

2020 ◽  
Vol 103 ◽  
pp. 169-180
Author(s):  
Hao Chen ◽  
Shuangfei Ding ◽  
Jinchao Tan ◽  
Dahai Yang ◽  
Yuanxing Zhang ◽  
...  
Keyword(s):  
Nlrp3 Inflammasome ◽  
Japanese Flounder ◽  
Edwardsiella Piscicida
Sign in / Sign up

Export Citation Format

Share Document