Atomic force microscopy-guided fractionation reveals the influence of cranberry phytochemicals on adhesion of Escherichia coli

Characterization of cranberry juice fractions for their role in anti-adhesive properties against pathogenicE. coliusing Atomic Force Microscopy (AFM).

Download Full-text

Atomic Force Microscopy Study of the Effect of Antimicrobial Peptides on the Cell Envelope of Escherichia coli

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.49.10.4085-4092.2005 ◽

2005 ◽

Vol 49 (10) ◽

pp. 4085-4092 ◽

Cited By ~ 122

Author(s):

M. Meincken ◽

D. L. Holroyd ◽

M. Rautenbach

Keyword(s):

Escherichia Coli ◽

Atomic Force Microscopy ◽

Morphological Changes ◽

Cell Envelope ◽

Microscopy Study ◽

Target Cells ◽

Force Microscopy ◽

E Coli ◽

Atomic Force ◽

Before And After

ABSTRACT The influences of the antibacterial magainin 2 and PGLa from the African clawed frog (Xenopus laevis) and the hemolytic bee venom melittin on Escherichia coli as the target cell were studied by atomic force microscopy (AFM). Nanometer-scale images of the effects of the peptides on this gram-negative bacterium's cell envelope were obtained in situ without the use of fixing agents. These high-resolution AFM images of the surviving and intact target cells before and after peptide treatment showed distinct changes in cell envelope morphology as a consequence of peptide action. Although all three peptides are lytic to E. coli, it is clear from this AFM study that each peptide causes distinct morphological changes in the outer membrane and in some cases the inner membrane, probably as a consequence of different mechanisms of action.

Download Full-text

Nanoscale Characterization of Escherichia coli Biofilm Formed under Laminar Flow Using Atomic Force Microscopy (AFM) and Scanning Electron Microscopy (SEM)

Bulletin of the Korean Chemical Society ◽

10.5012/bkcs.2008.29.11.2114 ◽

2008 ◽

Vol 29 (11) ◽

pp. 2114-2118 ◽

Cited By ~ 11

Keyword(s):

Electron Microscopy ◽

Escherichia Coli ◽

Scanning Electron Microscopy ◽

Atomic Force Microscopy ◽

Laminar Flow ◽

Force Microscopy ◽

Atomic Force ◽

Nanoscale Characterization ◽

Scanning Electron

Download Full-text

Rapid, Refined, and Robust Method for Expression, Purification, and Characterization of Recombinant Human Amyloid-beta M1-42

10.26434/chemrxiv.7725002.v1 ◽

2019 ◽

Author(s):

Priya Prakash ◽

Travis Lantz ◽

Krupal P. Jethava ◽

Gaurav Chopra

Keyword(s):

Amyloid Beta ◽

Western Blots ◽

Force Microscopy ◽

E Coli ◽

Atomic Force ◽

Set Up ◽

Short Time

Amyloid plaques found in the brains of Alzheimer’s disease (AD) patients primarily consists of amyloid beta 1-42 (Ab42). Commercially, Ab42 is synthetized using peptide synthesizers. We describe a robust methodology for expression of recombinant human Ab(M1-42) in Rosetta(DE3)pLysS and BL21(DE3)pLysS competent E. coli with refined and rapid analytical purification techniques. The peptide is isolated and purified from the transformed cells using an optimized set-up for reverse-phase HPLC protocol, using commonly available C18 columns, yielding high amounts of peptide (~15-20 mg per 1 L culture) in a short time. The recombinant Ab(M1-42) forms characteristic aggregates similar to synthetic Ab42 aggregates as verified by western blots and atomic force microscopy to warrant future biological use. Our rapid, refined, and robust technique to purify human Ab(M1-42) can be used to synthesize chemical probes for several downstream in vitro and in vivo assays to facilitate AD research.

Download Full-text