Trivalent Cation Induced Bundle Formation of Filamentous fd Phages

Abstract

Bacteriophages are filamentous polyelectrolyte viral rods infecting only bacteria. In this study, we investigate the bundle formation of fd phages with trivalent cations having different ionic radii (Al(3+) , La(3+) and Y(3+) ) at various phage and counterion concentrations, and at varying bundling times. Aggregated phage bundles were detected at relatively low trivalent counterion concentrations (1 mM). Although 10 mM and 100 mM Y(3+) and La(3+) treatments formed larger and more intertwined phage bundles, Al(3+) and Fe(3+) treatments lead to the formation of networking filaments. Energy dispersive X-ray spectroscopy (EDX) analyses confirmed the presence of C, N and O peaks on densely packed phage bundles. Immunofluorescence labelling and ELISA analyses with anti-p8 antibodies showed the presence of phage filaments after bundling.

Therapeutic Potential of Biomineralization‐Based Engineering

“…[63] Besides, the bridge molecules that have multivalent interactions with a single virus particle, such as multivalent cations, dendrimers, polypeptides, and cementing proteins, can induce the assembly of a single viral nanoparticle into a highly organized 3D structure. [64] The self-assembly of viral proteins and nanoparticles benefits the bottom-up construction of addressable mesoscale nanotemplates for the fabrication of tunable hybrid materials. [65]…”

“…Furthermore, through the incorporation of multifunctional modalities into the protein building blocks, the assembly of QD and AuNP can be simultaneously achieved with precise topological control . Besides, the bridge molecules that have multivalent interactions with a single virus particle, such as multivalent cations, dendrimers, polypeptides, and cementing proteins, can induce the assembly of a single viral nanoparticle into a highly organized 3D structure . The self‐assembly of viral proteins and nanoparticles benefits the bottom‐up construction of addressable mesoscale nanotemplates for the fabrication of tunable hybrid materials…”

Bulk Phase Behavior vs Interface Adsorption: Specific Multivalent Cation and Anion Effects on BSA Interactions

“…Under certain conditions, cations can thereby induce attractive forces, e.g., between macro-anions 39 and bridge particles of equal charge, such as polyelectrolytes, 40 surfactants, 41 or actin filaments. 42 Cations can induce charge inversion in biological membranes, 43 anionic liposomes 44 and globular proteins. 45 Our group observed a complex phase behavior for globular proteins (human and bovine serum albumins, β-lactoglobulin, ovalbumin) in the presence of multivalent cations such as Cd 2+ , Zn 2+ , La 3+ , Al 3+ , Y 3+ , Ho 3+ and Fe 3+ .…”

“…Due to the attractive interaction between opposite charges, cations can bind to negatively charged molecules. Under certain conditions, cations can thereby induce attractive forces, e.g., between macro-anions and bridge particles of equal charge, such as polyelectrolytes, surfactants, or actin filaments . Cations can induce charge inversion in biological membranes, anionic liposomes and globular proteins .…”

Bacteriophage Engineering for Improved Copper Ion Binding

“…Formation of phage agglomerates have been previously demonstrated by various studies elsewhere due to the electrostatic interactions between negatively charged virus molecules and positively charged counterions. [20,[26][27][28] Zaman et al induced the formation of copper oxide particles by applying a reducing agent after phage bundle formation triggered by Cu(II) incubation process. [26] However, in our study, Cu(II) binding peptide was observed to induce the reduction process alone without the presence of a reducing agent.…”