Significance of the pH-induced conformational changes in the structure of C-reactive protein measured by dual polarization interferometry
Journal
Biosensors and Bioelectronics
Journal Volume
26
Journal Issue
2
Pages
822-827
Date Issued
2010
Author(s)
Abstract
Emerging evidence indicates that the conformation of C-reactive protein (CRP) plays important roles in human inflammation and cardiovascular disease (CVD). The different conformations in the structure of CRP under different pH conditions remain an important issue to be investigated for explaining various functions of CRP under certain physiologic and pathologic conditions. We directly measured the pH-induced conformational changes in the structure of CRP by dual polarization interferometry (DPI). The CRP was attached to an aldehyde-functionalized DPI sensor chip at a concentration of 50μg/ml, and attained 2.019ng/mm2 to form a surface coverage with a 1.71×10-14mol/mm2 CRP monolayer. A pentagonal structure with an average monolayer thickness value of 5.70±0.12nm and a layer density of 0.374±0.058g/cm2 was obtained at pH 7.0. Moreover, the DPI biosensor signals directly reflected the considerable structural parameters and phenomena of conformational changes of CRP in a pH range of 2.0-10.0. The results obtained showed that the pentameric structure of CRP might dissociated into monomers or monomer aggregates as the pH shifts toward both acidic and alkaline conditions, but only partial rearrangements of CRP subunits might occur at extremely acidic physiological conditions. Considering the proinflammatory effect and subclinical chronic inflammation, pH-induced conformational changes in the structure of CRP between monomeric and pentameric formations may strongly relate to vascular atherosclerosis and subsequent CVD. ? 2010 Elsevier B.V.
SDGs
Other Subjects
Alkaline conditions; C-reactive proteins; Cardio-vascular disease; Chronic inflammation; Conformational change; Dual polarization interferometry; Functionalized; Monolayer thickness; Pathologic conditions; pH condition; pH range; Physiological condition; Proinflammatory; Sensor chips; Structural parameter; Surface coverages; Aldehydes; Biosensors; Conformations; Diseases; Interferometry; Monolayers; Monomers; Pathology; Physiology; Polarization; pH effects; aldehyde; C reactive protein; monomer; accuracy; acidity; alkalinity; amination; article; biosensor; calibration; conformational transition; dual polarization interferometry; interferometry; pH; protein structure; quantitative analysis; C-Reactive Protein; Hydrogen-Ion Concentration; Interferometry; Protein Conformation; Protein Denaturation; Refractometry
Type
journal article