Influence of pixelization on height measurement in atomic force microscopy

Tolstova, Anna P.; Dubrovin, Evgeniy V.

doi:10.1016/j.ultramic.2019.112846

Cited by 4 publications

(4 citation statements)

References 33 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Due to high biocompatibility and nontoxicity of the proteins, their use as a factor that induces protein unfolding may have a particular interest in biotechnology and medicine. error was less than 2% for the studied proteins) 42 .…”

Section: Discussionmentioning

confidence: 78%

See 1 more Smart Citation

Myeloperoxidase-induced fibrinogen unfolding and clotting

Barinov¹,

Pavlova

Tolstova

et al. 2021

Preprint

Self Cite

View full text Add to dashboard Cite

Fibrinogen is a major protein of blood coagulation system and is a promising component of biomaterials and protein matrixes. Conformational changes of fibrinogen underlie the important mechanism of thrombin mediated fibrinogen clotting but also may induce the loss of its biological activity and (amyloid) aggregation. Understanding and controlling of fibrinogen unfolding is important for the development of fibrinogen based materials with tunable properties. We have discovered that myeloperoxidase induces denaturation of fibrinogen molecules followed by fibrinogen clotting, which is not thrombin-dependent. This is the first example of ATP-independent, non-targeted protein-induced protein denaturation. The morphological structure of unfolded fibrinogen molecules and “non-conventional” fibrinogen clots has been characterized using high-resolution atomic force microscopy and scanning electron microscopy techniques. Circular dichroism (CD) spectroscopy has shown no significant changes of the secondary structure of the fibrinogen clots. The absorbance spectrophotometry has demonstrated that the kinetics of myeloperoxidase induced fibrinogen clotting strongly decays with growth of ionic strength indicating a major role of the Debye screening effect in regulating of this process. The obtained results provide with the novel concepts of protein unfolding and open new insights into fibrinogen clotting. Moreover, they give new possibilities in biotechnological and biomedical applications, e.g., for regulation of fibrinogen clotting and platelet adhesion and for the development of fibrinogen-based matrices.The organization of a protein molecule is characterized by different hierarchical levels such as primary, secondary, tertiary and quaternary structure. Protein unfolding or denaturation, i.e. its transformation to a lower order structure (and loss of a higher order structure), is a biologically and biotechnologically relevant process. Protein unfolding is a prerequisite for an alternative folding pathway including amyloid aggregation 1,2. Unfolded proteins may be used in development of protein films and coatings with special properties such as enhanced mechanical stability 3–5, resistance to protein adsorption or platelet adhesion 6,7 and other advantages 8. Unfolding of a protein molecule may lead to the loss of its biological function 9 that has important consequences in biosensor 10,11 and pharmaceutical applications 12.

show abstract

Section: Discussionmentioning

confidence: 78%

“…The scan rate was typically 1 Hz with 1024×1024 pixels. The pixel resolution was 1 pixel/nm that provides high accuracy of the determination of the mean height of protein globules (pixelization associated error was less than 2% for the studied proteins) 42 .…”

Section: Methodsmentioning

confidence: 99%

Myeloperoxidase-induced fibrinogen unfolding and clotting

Barinov¹,

Pavlova

Tolstova

et al. 2021

Preprint

Self Cite

View full text Add to dashboard Cite

show abstract

“…The characteristic size of hexagonal structures was obtained by averaging diameters of Dps molecules measured in all three directions of protein ordering. The height of protein globules was measured manually as the difference between the level of the highest point on a globule and a substrate surface; AFM images with a pixel size no larger than 2 nm have been used for height analysis [45]. For contour length measurements, a DNA contour was rendered by a polyline (for DNA-Dps complexes a polyline was drawn through the center of Dps molecules).…”

Section: Data Processingmentioning

confidence: 99%

Spatial organization of Dps and DNA–Dps complexes

Dubrovin

Dadinova

Petoukhov

et al. 2021

Journal of Molecular Biology

Self Cite

View full text Add to dashboard Cite

“…The scan rate was typically 1 Hz with 1024 × 1024 pixels. The pixel resolution was 1 pixel/nm that provides high accuracy of the determination of the mean height of protein globules (pixelization associated error was less than 2% for the studied proteins; Tolstova & Dubrovin, 2019).…”

Section: Methodsmentioning

confidence: 99%