Category: Proteomics

According to a 2019 study published in *BMC Genomics*, a proteome-wide analysis of 145 plant species revealed a diverse isoelectric point (pI) range of 1.99 to 13.96 for plant proteins. This wide range shows that the isoelectric point of plant proteins is not a single value but a characteristic spectrum influenced by many factors.

Over 18,000 proteins have been identified in the African clawed frog, *Xenopus laevis*, alone, illustrating that answering exactly how many proteins are in a frog is not as simple as counting genes. The total number is not a static figure but a dynamic quantity that varies based on developmental stage, tissue, and environmental conditions.

Over 500,000 different proteins can be expressed in the human body, but in mass spectrometry analysis, it is not always possible to uniquely identify every single one. This challenge gives rise to the concept of a protein group, a set of proteins that cannot be distinguished from one another based on the identified peptides.

According to the National Institutes of Health, comparative modeling is currently the most accurate computational method for predicting protein structure, especially when related proteins are available. This approach is a core component of what is comparative protein analysis, a broad field that uses biological comparisons to decipher function, structure, and expression.

In the field of medicine, an unusually low blood level of haptoglobin can be a sign of hemolytic anemia, a disorder where red blood cells are destroyed faster than they are replaced. This protein, abbreviated HP, most commonly stands for Haptoglobin, a critical molecule with several biological functions that go beyond simple hemoglobin binding.

Over 90% of protein electrophoresis procedures utilize polyacrylamide gels, a synthetic matrix that acts as a molecular sieve. This technique, known as PAGE, is the fundamental process used to separate proteins based on size, charge, or shape in laboratory settings, directly answering the query which gel is used for protein analysis.

Containing over 60% glycine in some plant species, glycine rich proteins (GRPs) are a highly diverse class of biomolecules found in a wide range of organisms, from plants to animals. Characterized by repetitive glycine motifs, these proteins exhibit a remarkable array of functions essential for survival and adaptation, from providing structural support to regulating gene expression.

Protein labeling has been a foundational technique in molecular biology since the use of radioactive isotopes in the mid-20th century. The process involves attaching detectable markers, such as fluorescent dyes or isotopic tracers, to proteins, making them visible for research. This critical procedure enables scientists to track protein movement, study cellular dynamics, and understand vital biological functions in real-time.

An average human cell can contain up to three billion proteins, with many embedded within cellular membranes. Understanding what is type 1 and type 2 protein is essential for cellular biology, as this specific classification details the distinct orientation of single-pass transmembrane proteins within the lipid bilayer, which profoundly affects their function.