Recombinant Human Beta-amyloid 39 protein

NPC2 (Niemann-Pick type C2) is a small, conserved lysosomal protein critical for intracellular cholesterol trafficking. It binds and transfers cholesterol within the lysosomal lumen in cooperation with NPC1. a transmembrane protein, to facilitate cholesterol export to cellular membranes. Mutations in the NPC2 gene cause Niemann-Pick disease type C (NP-C), a rare lysosomal storage disorder characterized by cholesterol and lipid accumulation, leading to progressive neurological deterioration and organ dysfunction.

Structurally, NPC2 is a 16 kDa glycoprotein with a hydrophobic pocket that specifically binds cholesterol. Its β-sandwich fold and conserved carbohydrate-binding domain enable interactions with vesicle membranes. Recombinant NPC2 proteins are generated using expression systems like *E. coli* or mammalian cells, often tagged for purification. These engineered proteins retain functional cholesterol-binding capacity and are essential tools for studying NP-C pathology, lysosomal biology, and cholesterol homeostasis.

Research applications include *in vitro* assays to dissect cholesterol transport mechanisms, drug screening for NP-C therapeutics, and structural studies to map mutation-induced functional defects. Recombinant NPC2 also holds therapeutic potential, such as enzyme replacement strategies or gene therapy vectors. Its role extends beyond NP-C, with emerging links to viral entry (e.g., Ebola) and immune modulation, highlighting broader biomedical relevance.

In summary, recombinant NPC2 bridges basic science and translational medicine, offering insights into lysosomal disorders and enabling targeted therapeutic development.

Beta-amyloid (Aβ) 39 is a recombinant protein variant derived from the proteolytic processing of the amyloid precursor protein (APP), a transmembrane protein implicated in Alzheimer’s disease (AD) pathology. Aβ peptides are generated through sequential cleavage of APP by β- and γ-secretases, producing fragments of varying lengths. While Aβ40 and Aβ42 are the most studied isoforms due to their strong association with AD, shorter variants like Aβ39 are gaining attention for their potential roles in disease mechanisms or as biomarkers. Aβ39 consists of 39 amino acids, lacking three residues at the C-terminus compared to Aβ42. This truncation may alter its aggregation propensity, solubility, or toxicity, making it a subject of interest in understanding Aβ heterogeneity.

Recombinant Aβ39 is typically produced using bacterial or mammalian expression systems, often fused with solubility-enhancing tags (e.g., His-tag) to facilitate purification. Its production enables controlled studies on Aβ behavior, such as aggregation kinetics, interactions with other proteins, or cellular toxicity assays. Unlike naturally occurring Aβ peptides extracted from biological samples, recombinant Aβ39 offers high purity and batch-to-batch consistency, critical for reproducible experimental outcomes. Researchers employ techniques like mass spectrometry, SDS-PAGE, and immunoassays to validate its structural integrity and concentration.

In AD research, Aβ39 serves as a tool to explore how subtle differences in Aβ length influence neurotoxicity and plaque formation. It may also help elucidate mechanisms of γ-secretase modulation, as shifts in Aβ peptide ratios (e.g., Aβ42/Aβ39) are linked to presenilin mutations in familial AD. Additionally, Aβ39 is used to develop antibodies or assays targeting specific Aβ epitopes, aiding in diagnostic or therapeutic advancements. Despite its lower abundance in vivo compared to Aβ40/42. studying Aβ39 contributes to a broader understanding of APP processing dysregulation and its role in neurodegenerative diseases. Its recombinant form thus bridges gaps between biochemical models and clinical observations in AD research.