What Can Be Learned by Knowing Only the Amino Acid Composition of Proteins?

The amino acid composition of proteins depends on many factors. It varies in organisms that are distant in taxonomic position. The amino acid composition of proteins depends on the localization of proteins in cells and tissues and the structure of proteins.

Exploring Compactness and Dynamics of Apomyoglobin.

Hydrogen-deuterium exchange mass spectrometry (HDX-MS) approach has become a valuable analytical complement to traditional methods. HDX-MS allows the identification of dynamic surfaces in proteins. We have shown that the introduction of various mutations into the amino acid sequence of whale apomyoglobin (apoMb) leads to a change in the number of exchangeable hydrogen atoms, which is associated with a change in its compactness in the native-like condition.

RNA-Binding S1 Domain in Bacterial, Archaeal and Eukaryotic Proteins as One of the Evolutionary Markers of Symbiogenesis.

The RNA-binding S1 domain is a β-barrel with a highly conserved RNA-binding site on its surface. This domain is an important part of the structures of different bacterial, archaeal, and eukaryotic proteins. A distinctive feature of the S1 domain is multiple presences (structural repeats) in proteins and protein complexes.

Promyelocytic leukemia protein (PML) knockout increases mitochondrial Ca uptake in HeLa cells.

The multifunctional promyelocytic leukemia protein (PML) is involved in the regulation of various cellular processes in both physiological and pathological conditions. Specifically, PML is one of the inositol-1,4,5-trisphosphate receptors (IPRs) activity regulators and can influence Ca transport from the endoplasmic reticulum (ER) to mitochondria. In this work, the effects of PML knockout on calcium homeostasis in the cytosol, ER, and mitochondria of HeLa cells were studied upon stimulation with histamine, which induces Ca mobilization from the ER via IPRs.