Self-assembling Peptide Nanofibers Containing D-amino Acids for Tetrandrine Delivery

Background: RADA-4 (Ac-RADARADARADARADA-NH2) is the most extensively studied and marketed self-assembling peptide, forming hydrogel, used to create defined threedimensional microenvironments for cell culture applications. Objectives: In this work, we use various biophysical techniques to investigate the length dependency of RADA aggregation and assembly. Methods: We synthesized a series of RADA-N peptides, N ranging from 1 to 4, resulting in four peptides having 4, 8, 12, and 16 amino acids in their sequence. Through a combination of various biophysical methods including thioflavin T fluorescence assay, static right angle light scattering assay, Dynamic Light Scattering (DLS), electron microscopy, CD, and IR spectroscopy, we have examined the role of chain-length on the self-assembly of RADA peptide. Results: Our observations show that the aggregation of ionic, charge-complementary RADA motifcontaining peptides is length-dependent, with N less than 3 are not forming spontaneous selfassemblies. Conclusion: The six biophysical experiments discussed in this paper validate the significance of chain-length on the epitaxial growth of RADA peptide self-assembly.

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Unusual Aggregation Properties of Single Amino Acid L-Lysine Hydrochloride

10.26434/chemrxiv.14152976 ◽

2021 ◽

Author(s):

Bharti Koshti ◽

Ramesh Singh ◽

Vivekshinh Kshtriya ◽

Shanka Walia ◽

Dhiraj Bhatia ◽

...

Keyword(s):

Amino Acids ◽

Amino Acid ◽

Self Assembly ◽

Short Term Memory ◽

Deionized Water ◽

The Body ◽

The Self ◽

Single Amino Acid ◽

Maple Syrup ◽

Self Assembling

. The self-assembly of single amino acids is very important topic of research since there are plethora of diseases like phenylketonuria, tyrosinemia, hypertryptophanemia, hyperglycinemia, cystinuria and maple syrup urine disease to name a few which are caused by the accumulation or excess of amino acids. These are in-born errors of metabolisms (IEM’s) which are caused due to the deficiency of enzymes involved in catabolic pathways of these enzymes. Hence, it is very pertinent to understand the fate of these excess amino acids in the body and their self-assembling behaviour at molecular level. From the previous literature reports it may be surmised that the single amino acids like Phenylalanine, Tyrosine, Tryptophan, Cysteine and Methionine assemble to amyloid like structures, and hence have important implications in the pathophysiology of IEM’s like phenylketonuria, tyrosinemia, hypertryptophanemia, cystinuria and hypermethioninemia respectively. In this manuscript we report the self-assembly of lysine hydrocholride to fiber like structures in deionized water. It could be observed that lysine assemble to globular structures in fresh condition and then gradually changes to fiber like morphologies by self-association over time after 24 hours. These fibers gradually change to tubular morphologies after 3 day followed by fractal irregular morphologies in 10 and 15 days respectively. Notably, lysine exists as positively charged amino acid at physiological pH and the amine groups in lysine remain protonated. Hence, the self-assembling properties of lysine hydrochloride in deionized water is also pertinent and give insights into the fate of this amino acid in body in case it remains unmetabolized. Further, MTT assays were done to analyse the toxicities of these aggregates and the assay suggest their cytotoxic nature on SHSY5Y neural cell lines. Hence, the aggregation of lysine may be attributed to the pathological symptoms caused in diseases like hyperlysinemia which is associated with the neurological problems like seizures and short-term memory as observed in case of amyloid diseases like Parkinson’s and Alzheimer’s to name a few.

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Self-Assembling Functionalized Amino Acids into Unusual Shapes

MRS Proceedings ◽

10.1557/opl.2011.129 ◽

2011 ◽

Vol 1312 ◽

Author(s):

Justin R. Barone ◽

Naresh K. Budhavaram ◽

Katherine J. Harvey

Keyword(s):

Amino Acids ◽

Hydrogen Bond ◽

Amino Acid ◽

Room Temperature ◽

Vinyl Sulfone ◽

Ethyl Vinyl ◽

Simple Route ◽

Self Assembling ◽

Component Systems ◽

Functionalized Amino Acids

ABSTRACTMulti-component small molecule systems that are amphiphilic or that can hydrogen bond end-to-end or side-to-side have been shown to self-assemble into a variety of shapes including fibers, rods, sheets, plates, spheres, and tubes. Recently, we have identified a simple route to self-assemble the same shapes from one-component systems. The structures form by attaching ethyl vinyl sulfone (EVS) to amino acids in water at room temperature. Choice of amino acid, amount of EVS substitution, and solvent conditions determine the final shape. Functionalized amino acids spontaneously form structures like fibers, spheres, tubes, and donuts when dried from solution. Here we focus on fibers and tubes.

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ChemInform Abstract: One-Pot Synthesis of Phenylseleno N-Acetyl α-Amino Acids: Supra-Molecular Self-Assembling in Organoselenium Compounds.

ChemInform ◽

10.1002/chin.201415210 ◽

2014 ◽

Vol 45 (15) ◽

pp. no-no

Author(s):

C. Parashiva Prabhu ◽

Prasad P. Phadnis ◽

Amey Wadawale ◽

K. Indira Priyadarsini ◽

Vimal K. Jain

Keyword(s):

Amino Acids ◽

Organoselenium Compounds ◽

One Pot ◽

One Pot Synthesis ◽

Self Assembling

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Bacterial acidity-triggered antimicrobial activity of self-assembling peptide nanofibers

Journal of Materials Chemistry B ◽

10.1039/c9tb00134d ◽

2019 ◽

Vol 7 (18) ◽

pp. 2915-2919 ◽

Cited By ~ 4

Author(s):

Weike Chen ◽

Shuxin Li ◽

Paul Renick ◽

Su Yang ◽

Nikhil Pandy ◽

...

Keyword(s):

Antimicrobial Activity ◽

Ph Change ◽

Self Assembling ◽

Microenvironmental Ph ◽

Peptide Nanofibers

A soluble, supramolecular peptide serves as an antimicrobial depot to release activated peptides in response to microenvironmental pH change around bacteria.

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