Dataset Information

A Conformationally Arrested Peptidomimetic Antibiotic Disrupts Selectively the Outer Membrane in Escherichia coli

ABSTRACT: Using a shotgun proteomics approach, the expressed proteome of total membrane fractions of Escherichia coli ATCC25922 cells was analyzed under i) normal growth, and ii) treatment with the novel peptidomimetic JB-95 (a structurally arrested cyclic peptide). By selectively disrupturing the outer membrane (OM), this peptidomimetic displayed a novel mechanism of action and opens new avenues for developing antibiotics that specifically target the OM of Gram-negative bacteria.

INSTRUMENT(S): LTQ Orbitrap, LTQ Orbitrap Velos

ORGANISM(S): Escherichia Coli

SUBMITTER: Christian Ahrens

LAB HEAD: Prof. John Robinson

PROVIDER: PXD002588 | Pride | 2015-12-07

REPOSITORIES: Pride

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Dataset's files

Source:

			Action	DRS
	20130311_02_memA1.RAW	Raw
	20130311_02_memA1.mgf	Mgf
	20130311_02_memA1.mgf.msgfplus_20ppm.mzid.gz	Mzid
	20130311_02_memA1.mgf.msgfplus_20ppm.pride.mztab.gz	Mztab
	20130311_02_memA1.pride.mgf.gz	Mgf

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A Peptidomimetic Antibiotic Targets Outer Membrane Proteins and Disrupts Selectively the Outer Membrane in Escherichia coli.

Urfer Matthias M Bogdanovic Jasmina J Lo Monte Fabio F Moehle Kerstin K Zerbe Katja K Omasits Ulrich U Ahrens Christian H CH Pessi Gabriella G Eberl Leo L Robinson John A JA

The Journal of biological chemistry 20151201 4

Increasing antibacterial resistance presents a major challenge in antibiotic discovery. One attractive target in Gram-negative bacteria is the unique asymmetric outer membrane (OM), which acts as a permeability barrier that protects the cell from external stresses, such as the presence of antibiotics. We describe a novel β-hairpin macrocyclic peptide JB-95 with potent antimicrobial activity against Escherichia coli. This peptide exhibits no cellular lytic activity, but electron microscopy and fl ...[more]

PMID: 26627837

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