Formation of the Native Topology of a Protein is due to the "Conserved but Non-Functional" Residues: A Case of Apomyoglobin Folding.

This paper is dedicated to the memory of Oleg B. Ptitsyn (1929-1999) and presents an answer to his question: "What is the role of conserved non-functional residues in protein folding?". This answer follows from the experimental works of three labs.

Function of the Conserved Non-Functional Residues in Apomyoglobin - to Determine and to Preserve Correct Topology of the Protein.

In this paper the answer to O. B. Ptitsyn's question "What is the role of conserved non-functional residues in apomyoglobin" is presented, which is based on the research results of three laboratories.

The Molten Globule State of a Globular Protein in a Cell Is More or Less Frequent Case Rather than an Exception.

Quite a long time ago, Oleg B. Ptitsyn put forward a hypothesis about the possible functional significance of the molten globule (MG) state for the functioning of proteins. MG is an intermediate between the unfolded and the native state of a protein.

sw ApoMb Amyloid Aggregation under Nondenaturing Conditions: The Role of Native Structure Stability.

Investigation of the molecular mechanisms underlying amyloid-related human diseases attracts close attention. These diseases, the number of which currently is above 40, are characterized by formation of peptide or protein aggregates containing a cross-β structure. Most of the amyloidogenesis mechanisms described so far are based on experimental studies of aggregation of short peptides, intrinsically disordered proteins, or proteins under denaturing conditions, and studies of amyloid aggregate formations by structured globular proteins under conditions close to physiological ones are still in the initial stage.

Membrane-induced changes in the holomyoglobin tertiary structure: interplay with function.

The effect of anionic phospholipid membranes on holomyoglobin (holoMb) conformation and deoxygenation was studied. HoloMb structural changes and behavior in the presence of membranes were monitored by a variety of techniques including far UV and near UV circular dichroism, tryptophan (Trp) fluorescence, absorbance in the Soret region, differential scanning calorimetry, (1)H-NMR spectroscopy, size exclusion chromatography, and macroscopic diffusion. Kinetics of deoxygenation was monitored by absorption at 581 nm.