All articles starting with P

Protein–energy malnutrition

Protein–energy malnutrition (PEM), or protein-energy undernutrition, is insufficient protein and energy intake to meet metabolic demand, spanning marasmus and kwashiorkor; childhood mortality 5–40%, treatable with therapeutic feeding and RUTF.

Protein–ligand docking

Protein–ligand docking is a computational method that predicts how a small molecule binds in a protein's binding site, producing a pose and a score, pioneered in the early 1980s.

Protein–protein docking

Protein–protein docking is a computational method that predicts the 3D structure of the complex formed when two proteins bind, complementing costly experimental methods like X-ray crystallography.

Protein–protein interaction prediction

Protein–protein interaction prediction is the use of computational methods, from genomic context and co-evolution to deep learning, to infer whether two proteins bind or otherwise associate.

Protein–protein interaction screening

Protein–protein interaction screening is a set of bench methods for testing which proteins interact: yeast two-hybrid reports binary contacts, while affinity purification with mass spectrometry reports stable complexes.

Proteinase K

Proteinase K (endopeptidase K, EC 3.4.21.64) is a broad-specificity subtilisin-like serine protease from Tritirachium album Limber, 277 aa, Asp39-His69-Ser224 triad, two calcium sites, used to digest proteins in DNA/RNA extraction.

Proteinogenic amino acid

A proteinogenic amino acid, also called a standard or encoded amino acid, is any amino acid incorporated into proteins during ribosomal translation, comprising 20 standard residues plus selenocysteine and pyrrolysine.

Proteinuria

Proteinuria, also called albuminuria, is excess protein in urine signaling kidney filter damage or transient causes. Defined by ACR categories (normal 2200 mg/g), it predicts kidney failure and cardiovascular risk.

Sep 19, 2026

ProteoGenix

ProteoGenix is a French antibody-development contract research organization headquartered in Schiltigheim, France, founded in 2003, providing antibody discovery, engineering, and production services to pharmaceutical, biotechnology, and diagnostics clients.

Proteogenomics

Proteogenomics is an integrative method that translates genome and transcriptome sequences into candidate protein databases for mass spectrometry searching, identifying novel peptides, confirming gene expression, and refining gene annotations.

Proteolysis

Proteolysis is the hydrolysis of peptide bonds by peptidases (proteases), classified by catalytic type (serine, cysteine, threonine, aspartic, glutamic, metallo, asparagine peptide lyase), cleavage position, and MEROPS clans and families.

Proteolysis targeting chimera

Proteolysis targeting chimeras (PROTACs) are bifunctional degrader drugs linking a target-protein ligand to an E3 ubiquitin ligase ligand, driving catalytic proteasomal destruction of disease proteins; key examples include ARV-110, ARV-471, and MZ1.

Sep 19, 2026

ProteomEdge (proteomics company)

ProteomEdge is a Swedish proteomics company in Stockholm, founded in 2023 by Human Protein Atlas and SciLifeLab researchers, selling labeled protein standards for mass spectrometry.

Proteomics

Proteomics, the large-scale study of proteins, also called proteome analysis; complementary to genomics and transcriptomics; dominated by bottom-up LC-MS/MS peptide analysis, with top-down intact-protein, single-cell, and spatial methods emerging.

Proteomics (institution)

PROTEOMICS is a Wiley-VCH peer-reviewed journal launched January 2001, the first devoted to proteomics, ISSN 1615-9853/1615-9861, semimonthly since 2006, with sister journal PROTEOMICS Clinical Applications (2007).

Proteorhodopsin

Proteorhodopsin (PR) is a retinal-containing, seven-helix light-driven proton pump discovered in 2000 by metagenomics of uncultured SAR86 marine bacteria from Monterey Bay; green (~525 nm) and blue (~490 nm) variants are among the most abundant microbial rhodopsins in the oceans.

Proteostasis

Proteostasis (protein homeostasis) is the cellular regulation of protein concentration, folding, interactions, localization, and degradation via the proteostasis network of chaperones, the ubiquitin-proteasome system, and autophagy; its decline underlies aging and proteinopathies.

Proter

Proter is a Sri Lankan Rummy card game of 13 deals, each with a different wild card from ace to king; players meld sets and runs, take whole discard piles, and the lowest score wins.

Proterozoic

The Proterozoic, or Proterozoic Eon, is the second of Earth's four geological eons, spanning 2,500 to 541 million years ago and forming most of the Precambrian.

Oct 15, 2026

Proterra

Proterra was an American electric vehicle technology company founded in 2004 and headquartered in Burlingame, California, that sold around 1,200 electric transit buses before filing for bankruptcy in August 2023.

Protest

Protest: coordinated public collective action expressing dissent, opposition, or vindication. Covers tactics (marches, strikes, boycotts, 250 nonviolent methods), theory, datasets (1.2M events, 1980–2020), effectiveness debates, and assembly-rights law.

Sep 24, 2026

Protest of Baraguá

The Protest of Baraguá (Protesta de Baraguá) was Cuban general Antonio Maceo's 1878 refusal to accept the Pact of Zanjón, which ended the Ten Years' War without independence.

Protest song

Protest song: a song written or adopted to voice opposition to social or political injustice; term coined in the 1960s USA, spanning civil rights "We Shall Overcome", Latin American revolutionary song, censorship cases, and modern anthems like "Baraye".

Protest the Hero

Protest the Hero, formerly Happy Go Lucky, is a Canadian progressive metal band from Whitby, Ontario, formed 1999. Six albums from Kezia (2005) to the fully independent Within (2026); Fortress went Gold in Canada; five Juno nominations, one win.

Protest vote

Protest vote: an insincere or invalid ballot cast to signal dissatisfaction, via fringe or antiestablishment parties, blank or spoiled ballots, or NOTA options; studied in France, Spain, Ecuador, and the 2024 US uncommitted campaigns.

Protestant and ecumenical roots of Christian democracy

The Protestant and ecumenical roots of Christian democracy are the Reformed and Lutheran social ethics, Protestant parties in the Netherlands and Nordics, and the ecumenical movement.

Protestant Ascendancy

Protestant Ascendancy: the anglophone Church-of-Ireland landed elite dominating Ireland's politics, land, and society from 1690 to 1800, also the ideology defending its privileges against Catholic relief and the United Irishmen.

Protestant Cemetery, Rome

The Protestant Cemetery, Rome (Cimitero Acattolico), a private non-Catholic burial ground beside the Pyramid of Caius Cestius since 1716, governed by 15 embassies, holding over 6,000 graves including Keats, Shelley, and Gramsci.

Protestant Church in the Netherlands

The Protestant Church in the Netherlands (Protestantse Kerk in Nederland, PKN) is the largest Protestant denomination in the Netherlands, formed on 1 May 2004 by merging three churches.