Isolation of Amyloid-like Protein Aggregates (APA) from white bread and their characterisation.

High temperature, acidic pH, and physical agitation are commonly observed during cooking or industrial food processing, which are often considered as favorable conditions, at least for some proteins, to misfold and form amyloid-like protein aggregates (APA). The proteins in various bakery products generally experience high temperatures that might lead to the formation of APA. To test this hypothesis, the presence of APA in white bread was examined in this study.

Discerning Modulation of α-Synuclein Amyloid Assembly by α-Crystallin.

Altered protein folding leading to the formation of structured aggregates such as amyloid fibrils has gained significant attention due to its association with neurodegenerative diseases. α-Synuclein, a small intrinsically disordered protein, gets transformed into amyloid fibrils under unfavorable conditions and contributes to the progression and pathology of Parkinson's disease (PD). Under normal physiological conditions, amyloid formation is controlled by many chaperones and chaperone-like proteins.

Amyloids and Amyloid-like Protein Aggregates in Foods: Challenges and New Perspectives.

Protein misfolding and amyloid formations are associated with many neurodegenerative and systemic diseases. The discovery of Alzheimer's disease and its association with the accumulation of Amyloid-β (Aβ) peptides in the plaques uncovered the pleiotropic nature of peptides/ proteins. As of today, more than 50 proteins/ peptides are reported to form amyloids or amyloid-like protein aggregates under different conditions, establishing that amyloid formation could be a generic property of many proteins.

First report of association of ' Phytoplasma asteris' with leaf yellowing and stunting disease in India.

(family Moringaceae) also known as the 'drumstick tree' is a significant nutritious and medicinal plant that is commonly grown in India and contains a variety of vital phytochemicals. is used in several Indian herbal medicine formulations to treat a variety of illnesses (Kumar and Rao 2021). Typical phytoplasma symptoms of leaf yellowing and stunting were observed in trees up to 10% incidence at Acharya Narendra Dev University of Agriculture & Technology, Ayodhya, Uttar Pradesh, India in November 2021 and stunting with less fruit bearings symptoms with 8% incidence in October 2021 at Jonnalakothapalle village of Mudigubba mandal of Ananthapuramu district in Andhra Pradesh, India (Fig.

Isolation and characterization of amyloid-like protein aggregates from soya beans and the effect of low pH and heat treatment on their stability.

Purified soya bean proteins (glycinin and conglycinin) are known to form amyloid-like aggregates in vitro at a higher temperature. Soya beans (chunks) are textured proteinaceous vegetables made from defatted soya flour by heating it above 100°C and extruding under high pressure. Therefore, it was assumed that subjecting the soya bean proteins to high temperatures raises the possibility of forming amyloids or amyloid-like protein aggregates.

Isolation and characterisation of milk-derived amyloid-like protein aggregates (MAPA) from cottage cheese.

Cottage cheese, extensively consumed worldwide, contains coagulated milk protein (casein), produced through boiling and acidification of milk. Casein forms amyloid or amyloid-like structures at high temperatures and low pH. Due to the similarities in the preparation of casein amyloids and cottage cheese, we hypothesized the presence of amyloid or amyloid-like protein aggregates in cottage cheese.

Structural and functional swapping of amyloidogenic and antimicrobial peptides: Redefining the role of amyloidogenic propensity in disease and host defense.

Peptides constitute an essential component of all organisms' protein homeostasis ranging from bacteria, plants, and animals. They have organically been evolved to perform a wide range of essential functions, including their role as neurotransmitters, antimicrobial peptides (AMPs), and hormones. AMPs are short peptides synthesized by almost all organisms, implicated in guarding the host from various microbial infections.

Heat treatment of soluble proteins isolated from human cataract lens leads to the formation of non-fibrillar amyloid-like protein aggregates.

The loss of crystallins solubility with aging and the formation of amyloid-like aggregates is considered the hallmark characteristic of cataract pathology. The present study was carried out to assess the effect of temperature on the soluble lens protein and the formation of protein aggregates with typical amyloid characteristics. The soluble fraction of lens proteins was subjected for heat treatment in the range of 40-60 °C, and the nature of protein aggregates was assessed by using Congo red (CR), thioflavin T (ThT), and 8-anilinonaphthalene-1-sulfonic acid (ANS) binding assays, circular dichroism (CD), Fourier-transform infrared (FT-IR) spectroscopy, and transmission electron microscopy (TEM).

Amyloid cross-sequence interaction between Aβ(1-40) and αA(66-80) in relation to the pathogenesis of cataract.

Alzheimer's disease (AD) and cataract represent two common protein misfolding diseases closely associated with aging. Growing evidence suggests that these two diseases may be interrelated with each other through cross-sequence interactions between β-amyloid (Aβ) peptide and the short aggregating peptides derived from proteolytic breakdown of α-crystallin. αΑ(66-80) is one of several peptides produced by the proteolytic breakdown of α-crystallin in aged eye lens.

Aggregation hot spots in the SARS-CoV-2 proteome may constitute potential therapeutic targets for the suppression of the viral replication and multiplication.

The emergence of novel coronavirus SARS-CoV-2 is responsible for causing coronavirus disease-19 (COVID-19) imposing serious threat to global public health. Infection of SARS-CoV-2 to the host cell is characterized by direct translation of positive single stranded (+ ss) RNA to form large polyprotein polymerase 1ab (pp1ab), which acts as precursor for a number of nonstructural and structural proteins that play vital roles in replication of viral genome and biosynthesis of new virus particles. The maintenance of viral protein homeostasis is essential for continuation of viral life cycle in the host cell.

First report on clover proliferation phytoplasma related strain associated with floral virescence in Uttar Pradesh, India.

R. Br. (Fam: Brassicaceae) is an ornamental, commonly known as hoary stock has an extremely fragrant flowers, which blooms in dense clusters in a large variety of colors.

Trehalose Inhibits the Heat-Induced Formation of the Amyloid-Like Structure of Soluble Proteins Isolated from Human Cataract Lens.

The age-dependent loss of solubility and aggregation of crystallins constitute the pathological hallmarks of cataract. Several biochemical and biophysical factors are responsible for the reduction of crystallins' solubility and formation of irreversible protein aggregates, which display amyloid-like characteristics. The present study reports the heat-induced aggregation of soluble proteins isolated from human cataract lenses and the formation of amyloid-like structures.

Computational investigation for modeling the protein-protein interaction of TasA-TapA: a decisive process in biofilm formation by Bacillus subtilis.

Biofilms have a significant role in microbial persistence, antibiotic resistance, and chronic infections; consequently, there is a pressing need for development of novel "anti-biofilm strategies." One of the fundamental mechanisms involved in biofilm formation is protein-protein interactions of "amyloid-like proteins" (ALPs) in the extracellular matrix. Such interactions could be potential targets for development of novel anti-biofilm strategies; therefore, assessing the structural features of these interactions could be of great scientific value.

Predicted aggregation-prone region (APR) in βB1-crystallin forms the amyloid-like structure and induces aggregation of soluble proteins isolated from human cataractous eye lens.

The aggregation of β-crystallins in the human eye lens constitutes a critical step during the development of cataract. We anticipated that the presence of Aggregation-Prone Regions (APRs) in their primary structure, which might be responsible for conformational change required for the self-assembly. To examine the presence of APRs, we systematically analyzed the primary structures of β-crystallins.

Impact of semen-derived amyloid (SEVI) on sperm viability and motility: its implication in male reproductive fitness.

Human semen contains a large number of macromolecules, including proteins/enzymes and carbohydrates, regulating and protecting sperm cells. Proteomic analysis of human seminal fluid led to the discovery of semen amyloids derived from short peptide fragments of the proteins prostatic acid phosphatase (PAP) and semenogelin (SG) which are known to play a crucial role in enhancing HIV infection. However, the relevance of their existence in human semen and role in maintaining sperm behavior remains unclear.

Pheromone peptide cOB1 from native Enterococcus faecalis forms amyloid-like structures: A new paradigm for peptide pheromones.

Pheromone peptides are an important component of bacterial quorum-sensing system. The pheromone peptide cOB1 (VAVLVLGA) of native commensal Enterococcus faecalis has also been identified as an antimicrobial peptide (AMP) and reported to kill the prototype clinical isolate strain of E. faecalis V583.

Thrombin stimulates gene expression and secretion of IL-11 via protease-activated receptor-1 and regulates extravillous trophoblast cell migration.

Extravillous trophoblast (EVT) migration and invasion is the crucial step for normal placental development. IL-11 is a cytokine regulating cell migration and invasion in cells and is a critical factor for successful implantation of an embryo. Higher expression of thrombin receptor PAR-1 was reported in early pregnancy.

The mechanism of phosphatidylcholine-induced interference of PAP (248-286) aggregation.

Seminal amyloids are well known for their role in enhancing HIV infection. Among all the amyloidogenic peptides identified in human semen, PAP was found to be the most active and was termed as semen-derived enhancer of viral infection (SEVI). Although amyloidogenic nature of the peptide is mainly linked with enhancement of the viral infection, the most active physiological conformation of the aggregated peptide remains inconclusive.

Mammalian antimicrobial peptide protegrin-4 self assembles and forms amyloid-like aggregates: Assessment of its functional relevance.

Protegrin-4 (PG-4) is a member of the porcine leukocyte protegrins family of cysteine-rich antimicrobial peptides (AMPs) isolated from Sus scrofa. It consists of 18 amino acid residues and works as a part of innate immune system. In this study, we examined the intrinsic aggregation propensity of this AMP using multiple computational algorithms, namely, TANGO, AGGRESCAN, FOLDAMYLOID, AMYLPRED, and ZYGGREGATOR, and found that the peptide is predicted to have a high propensity for the β sheet formation that disposes this peptide to be amyloidogenic.

Structure, function and antagonism of semen amyloids.

Amyloid fibrils are linear polypeptide aggregates with a cross-β structure. These fibrils are best known for their association with neurodegenerative diseases, such as Alzheimer's or Parkinson's, but they may also be used by living organisms as functional units, e.g.

Effect of Green Tea Polyphenol Epigallocatechin-3-gallate on the Aggregation of αA(66-80) Peptide, a Major Fragment of αA-crystallin Involved in Cataract Development.

Purpose: Crystallin is a major protein present in eye lens. Peptide fragment αA(66-80) derived from αA-crystallin possesses high aggregation propensity and forms amyloid-like structures. αA(66-80) aggregates are known to interact with soluble crystallins and destabilize native structures that subsequently undergo aggregation.

Antimicrobial peptide (Cn-AMP2) from liquid endosperm of Cocos nucifera forms amyloid-like fibrillar structure.

Cn-AMP2 is an antimicrobial peptide derived from liquid endosperm of coconut (Cocos nucifera). It consists of 11 amino acid residues and predicted to have high propensity for β-sheet formation that disposes this peptide to be amyloidogenic. In the present study, we have examined the amyloidogenic propensities of Cn-AMP2 in silico and then tested the predictions under in vitro conditions.

Enhanced Fibril Fragmentation of N-Terminally Truncated and Pyroglutamyl-Modified Aβ Peptides.

N-terminal truncation and pyroglutamyl (pE) formation are naturally occurring chemical modifications of the Aβ peptide in Alzheimer's disease. We show herein that these two modifications significantly reduce the fibril length and the transition midpoint of thermal unfolding of the fibrils, but they do not substantially perturb the fibrillary peptide conformation. This observation implies that the N terminus of the unmodified peptide protects Aβ fibrils against mechanical stress and fragmentation and explains the high propensity of pE-modified peptides to form small and particularly toxic aggregates.

Peptide dimer structure in an Aβ(1-42) fibril visualized with cryo-EM.

Alzheimer's disease (AD) is a fatal neurodegenerative disorder in humans and the main cause of dementia in aging societies. The disease is characterized by the aberrant formation of β-amyloid (Aβ) peptide oligomers and fibrils. These structures may damage the brain and give rise to cerebral amyloid angiopathy, neuronal dysfunction, and cellular toxicity.

Structure and biomedical applications of amyloid oligomer nanoparticles.

Amyloid oligomers are nonfibrillar polypeptide aggregates linked to diseases, such as Alzheimer's and Parkinson's. Here we show that these aggregates possess a compact, quasi-crystalline architecture that presents significant nanoscale regularity. The amyloid oligomers are dynamic assemblies and are able to release their individual subunits.