Effect of Lipid-Based Nanostructure on Protein Encapsulation within the Membrane Bilayer Mimetic Lipidic Cubic Phase Using Transmembrane and Lipo-proteins from the Beta-Barrel Assembly Machinery

Abstract

A fundamental understanding of the effect of amphiphilic protein encapsulation on the nanostructure of the bicontinuous cubic phase is crucial to progressing biomedical and biological applications of these hybrid protein-lipid materials, including as drug delivery vehicles, as biosensors, biofuel cells and for in meso crystallization. The relationship between the lipid nanomaterial and the encapsulated protein, however, remains poorly understood. In this study, we investigated the effect of incorporating the five transmembrane and lipo-proteins which make up the β-barrel assembly machinery from Gram-negative bacteria within a series of bicontinuous cubic phases. The transmembrane β-barrel BamA caused an increase in lattice parameter of the cubic phase upon encapsulation. By contrast, the mainly hydrophilic lipo-proteins BamB-E caused the cubic phase lattice parameters to decrease, despite their large size relative to the diameter of the cubic phase water channels. Analysis of the primary amino acid sequence was used to rationalize this effect, based on specific interactions between aromatic amino acids within the proteins and the polar-apolar interface. Other factors that were found to have an effect were lateral bilayer pressure and rigidity within the lipid bilayer, water channel diameter, and size and structure of the lipo-proteins. The data presented suggest that hydrophilic bioactive molecules can be selectively encapsulated within the cubic phase by using a lipid anchor or aromatic amino acids, for drug delivery or biosensing applications.

Direct demonstration of lipid phosphorylation in the lipid bilayer of the biomimetic bicontinuous cubic phase using the confined enzyme lipid A phosphoethanolamine transferase

“…This was also observed in previous work for other large amphiphilic proteins with either a-helical or b-barrel transmembrane domains: the D2L receptor, Ag43, GPR41 and GPR43, and BamA. 1,12,14,15,52 Activity of NmEptA in DOPE doped MO. The individual effect of DOPE and DOG on the MO diamond cubic Q D II phase nanostructure was probed to better understand the conversion of DOPE to DOG by NmEptA.…”

“…A number of recent studies have therefore investigated changes to the lipidic nanostructure caused by the incorporation of amphiphilic proteins and peptides within the bicontinuous cubic phases. 1,[12][13][14][15][16][17] Hydrophobic mismatch, hydrophilic domain size and charge were found to be the most important factors affecting the nanostructure.…”

Cubic Liquid Crystalline Nanostructures Involving Catalase and Curcumin: BioSAXS Study and Catalase Peroxidatic Function after Cubosomal Nanoparticle Treatment of Differentiated SH-SY5Y Cells

“…The entrapment of biomolecules of various dimensions and hydrophilicities is achievable in such nanocarriers as well as their sustained release [10,12]. For example, LCPs have been used to encapsulate proteins of different concentrations and sizes from Cyt C (12 kDa) to fibrinogen (340 kDa) [8,11,20,21,22,23,24,25,26,27]. High encapsulation efficacy has been reported for hydrophilic guest macromolecules such as brain-derived neurotrophic factor (BDNF), ovalbulmin and protein vaccines [11,20,21,22,23,24].…”

“…High encapsulation efficacy has been reported for hydrophilic guest macromolecules such as brain-derived neurotrophic factor (BDNF), ovalbulmin and protein vaccines [11,20,21,22,23,24]. Soluble, peripheral, and integral membrane proteins have been studied in LCPs in relation to in meso protein crystallization, biosensor development involving encapsulated enzymes, and drug-delivery systems [21,22,23,24,25,26,27,28]. LCP-derived nanocarriers are increasingly used in a range of applications employing lipophilic drugs and theranostic agents [14,15,16,17,18,19].…”

Nanosized Delivery Systems for Therapeutic Proteins: Clinically Validated Technologies and Advanced Development Strategies

“…In fact, the protein may be surrounded by the lipid membrane or occupy the hydrophobic transmembrane region, depending on the nature of the proteins and the lipids involved, which are capable of forming electrostatic and hydrophobic interactions, hydrogen bonds, due to the polar and hydrophobic groups present in their complex structure (Lee, 2004;McClements, 2018). Computational simulations have also been used for a deeper understanding of protein-lipid interaction (Khan et al, 2016;van't Hag et al, 2016).…”