Characterization of two relacidines belonging to a novel class of circular lipopeptides that act against Gram‐negative bacterial pathogens

Therapeutic options to combat Gram-negative bacterial pathogens are dwindling with increasing antibiotic resistance. This study presents a proof of concept for the heterologous-expression approach to expand on the novel antibiotic class of darobactins and to generate analogs with different activities and pharmacokinetic properties.

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Corrigendum to “Crystal structures and biochemical characterization of DNA sliding clamps from three Gram-negative bacterial pathogens” [J. Struct. Biol. 204 (3) (2018) 396–405]

Journal of Structural Biology ◽

10.1016/j.jsb.2019.05.003 ◽

2019 ◽

Vol 207 (2) ◽

pp. 234

Author(s):

Amy E. McGrath ◽

Alexander P. Martyn ◽

Louise R. Whittell ◽

Fay E. Dawes ◽

Nehad S. El Salamouni ◽

...

Keyword(s):

Crystal Structures ◽

Biochemical Characterization ◽

Bacterial Pathogens ◽

Gram Negative ◽

Sliding Clamps

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Crystal structures and biochemical characterization of DNA sliding clamps from three Gram-negative bacterial pathogens

Journal of Structural Biology ◽

10.1016/j.jsb.2018.10.008 ◽

2018 ◽

Vol 204 (3) ◽

pp. 396-405 ◽

Cited By ~ 3

Author(s):

Amy E. McGrath ◽

Alexander P. Martyn ◽

Louise R. Whittell ◽

Fay E. Dawes ◽

Jennifer L. Beck ◽

...

Keyword(s):

Crystal Structures ◽

Biochemical Characterization ◽

Bacterial Pathogens ◽

Gram Negative ◽

Sliding Clamps

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Phenotypic and Genotypic Characterization of Cephalosporin-, Carbapenem-, and Colistin-Resistant Gram-Negative Bacterial Pathogens in Lebanon, Jordan, and Iraq

Journal of Global Antimicrobial Resistance ◽

10.1016/j.jgar.2021.08.005 ◽

2021 ◽

Author(s):

Rima A. Moghnieh ◽

Jihane A. Moussa ◽

Mohamed Abdel Aziz ◽

Ghassan M. Matar

Keyword(s):

Bacterial Pathogens ◽

Gram Negative ◽

Genotypic Characterization ◽

Phenotypic And Genotypic Characterization

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Application of commercial test-systems to identify gram-negative facultatively anaerobic bacteria

Agricultural science and practice ◽

10.15407/agrisp3.01.043 ◽

2016 ◽

Vol 3 (1) ◽

pp. 43-48 ◽

Cited By ~ 1

Author(s):

V. Patyka ◽

L. Butsenko ◽

L. Pasichnyk

Keyword(s):

Erwinia Amylovora ◽

Anaerobic Bacteria ◽

Biochemical Properties ◽

Test System ◽

Phytopathogenic Bacteria ◽

Gram Negative ◽

Test Systems ◽

Facultatively Anaerobic ◽

Microbiological Methods

Aim. To validate the suitability of commercial API 20E test-system (bioMerieux) for the identifi cation and characterization of facultative gram-negative phytopathogenic bacterial isolates. Methods. Conventional mi- crobiological methods, API 20E test-system (bioMerieux) according to the manufacturer’s instructions. Re- sults. The identifi cation results for Erwinia amylovora, Pectobacterium carotovorum and Pantoea agglome- rans isolates were derived from the conventional and API 20E test systems, which, were in line with the literature data for these species. The API 20E test-system showed high suitability for P. agglomerans isolates identifi cation. Although not all the species of facultatively anaerobic phytopathogenic bacteria may be identi- fi ed using API 20E test-system, its application will surely allow obtaining reliable data about their physiologi- cal and biochemical properties, valuable for identifi cation of bacteria, in the course of 24 h. Conclusions. The results of tests, obtained for investigated species while using API 20E test-system, and those of conventional microbiological methods coincided. The application of API 20E test-system (bioMerieux) ensures fast obtain- ing of important data, which may be used to identify phytopathogenic bacteria of Erwinia, Pectobacterium, Pantoea genera.

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Electrophysiological Characterization of Transport Across Outer Membrane Channels from Gram-Negative Bacteria in Their Native Environment

10.26434/chemrxiv.8282204.v1 ◽

2019 ◽

Author(s):

Jiajun Wang ◽

Rémi Terrasse ◽

Jayesh Arun Bafna ◽

Lorraine Benier ◽

Mathias Winterhalter

Keyword(s):

Outer Membrane ◽

Lipid Membrane ◽

Membrane Vesicles ◽

Outer Membrane Vesicles ◽

Multi Drug Resistance ◽

Gram Negative Bacteria ◽

Membrane Channels ◽

Gram Negative ◽

Electrophysiological Characterization

Multi-drug resistance in Gram-negative bacteria is often associated with low permeability of the outer membrane. To investigate the role of membrane channels in the uptake of antibiotics, we extract, purify and reconstitute them into artificial planar membranes. To avoid this time-consuming procedure, here we show a robust approach using fusion of native outer membrane vesicles (OMV) into planar lipid bilayer which moreover allows also to some extend the characterization of membrane protein channels in their native environment. Two major membrane channels from Escherichia coli, OmpF and OmpC, were overexpressed from the host and the corresponding OMVs were collected. Each OMV fusion revealed surprisingly single or only few channel activities. The asymmetry of the OMV´s translates after fusion into the lipid membrane with the LPS dominantly present at the side of OMV addition. Compared to conventional reconstitution methods, the channels fused from OMVs containing LPS have similar conductance but a much broader distribution. The addition of Enrofloxacin on the LPS side yields somewhat higher association (kon) and lower dissociation (koff) rates compared to LPS-free reconstitution. We conclude that using outer membrane vesicles is a fast and easy approach for functional and structural studies of membrane channels in the native membrane.

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Faculty Opinions recommendation of Ligand-free palladium-mediated site-specific protein labeling inside gram-negative bacterial pathogens.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.718007467.793476213 ◽

2013 ◽

Author(s):

Barbara Imperiali ◽

Marthe Walvoort

Keyword(s):

Bacterial Pathogens ◽

Specific Protein ◽

Protein Labeling ◽

Site Specific ◽

Gram Negative ◽

Ligand Free

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A Fish Galectin-8 Possesses Direct Bactericidal Activity

International Journal of Molecular Sciences ◽

10.3390/ijms22010376 ◽

2020 ◽

Vol 22 (1) ◽

pp. 376

Author(s):

Tengfei Zhang ◽

Shuai Jiang ◽

Li Sun

Keyword(s):

Bactericidal Activity ◽

Bacterial Pathogens ◽

Bactericidal Effect ◽

Immune Defense ◽

Carbohydrate Binding ◽

Dependent Manner ◽

Animal Cells ◽

Gram Negative ◽

Tongue Sole ◽

Wide Range

Galectins are a family of animal lectins with high affinity for β-galactosides. Galectins are able to bind to bacteria, and a few mammalian galectins are known to kill the bound bacteria. In fish, no galectins with direct bactericidal effect have been reported. In the present study, we identified and characterized a tandem repeat galectin-8 from tongue sole Cynoglossus semilaevis (designated CsGal-8). CsGal-8 possesses conserved carbohydrate recognition domains (CRDs), as well as the conserved HXNPR and WGXEE motifs that are critical for carbohydrate binding. CsGal-8 was constitutively expressed in nine tissues of tongue sole and up-regulated in kidney, spleen, and blood by bacterial challenge. When expressed in HeLa cells, CsGal-8 protein was detected both in the cytoplasm and in the micro-vesicles secreted from the cells. Recombinant CsGal-8 (rCsGal-8) bound to lactose and other carbohydrates in a dose dependent manner. rCsGal-8 bound to a wide range of gram-positive and gram-negative bacteria and was co-localized with the bound bacteria in animal cells. Lactose, fructose, galactose, and trehalose effectively blocked the interactions between rCsGal-8 and different bacteria. Furthermore, rCsGal-8 exerted potent bactericidal activity against some gram-negative bacterial pathogens by directly damaging the membrane and structure of the pathogens. Taken together, these results indicate that CsGal-8 likely plays an important role in the immune defense against some bacterial pathogens by direct bacterial interaction and killing.

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