Examining Protein Crystallization Using Scanning Electron Microscopy

2012 ◽  
Vol 19 (1) ◽  
pp. 145-149 ◽  
Author(s):  
Kathryn Gomery ◽  
Elaine C. Humphrey ◽  
Rodney Herring
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Crystal Growth ◽  
Early Stage ◽  
Protein Crystallization ◽  
Crystal Nucleation ◽  
Protein Crystal ◽  
Microscopy Imaging ◽  
Protein Crystal Growth ◽  
Scanning Electron

AbstractElucidation of protein structure using X-ray crystallography relies on the quality of the crystal. Crystals suffer from many different types of disorder, some of which occur during crystal nucleation and early crystal growth. To date, there are few studies surrounding the quality and nucleation of protein crystals partly due to difficulties surrounding viewing biological samples at high resolution. Recent research has led our current understanding of nucleation to be a two-step mechanism involving the formation of nuclei from dense liquid clusters; it is still unclear whether nuclei first start as amorphous aggregate or as crystalline lattices. Our research examines this mechanism through the use of electron microscopy. Using scanning electron microscopy imaging of the protein crystal growth process, a stacking, spiraling manner of growth is observed. The tops of the pyramid-like tetragonal protein crystal structures measure ~0.2 μm across and contain ~125,000 lysozyme units. This noncrystalline area experiences strain due to growth of the protein crystal. Our work shows that it is possible to view detailed early stage protein crystal growth using a wet scanning electron microscopy technique, thereby overcoming the problem of viewing liquids in a vacuum.

scholarly journals Intraocular lens biofilm formation supported by scanning electron microscopy imaging

2019 ◽  
Vol 67 (10) ◽  
pp. 1708
Author(s):  
Dipankar Das ◽  
Harsha Bhattacharjee ◽  
Krishna Gogoi ◽  
JayantaK Das ◽  
Puneet Misra ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Intraocular Lens ◽  
Biofilm Formation ◽  
Microscopy Imaging ◽  
Scanning Electron

scholarly journals Correlation of X-ray Computed Nanotomography and Scanning Electron Microscopy Imaging of Collagen Scaffolds

2018 ◽  
Vol 24 (S2) ◽  
pp. 104-105
Author(s):  
Dominika Kalasova ◽  
Veronika Pavlinakova ◽  
Tomas Zikmund ◽  
Lucy Vojtova ◽  
Jozef Kaiser
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Collagen Scaffolds ◽  
Microscopy Imaging ◽  
X Ray ◽  
X Ray Computed ◽  
Scanning Electron

Effect of sedimentary environment on shale lithofacies in the lower third member of the Shahejie Formation, Zhanhua Sag, eastern China

2017 ◽  
Vol 5 (4) ◽  
pp. T487-T501 ◽  
Author(s):  
Tingwei Li ◽  
Zhenxue Jiang ◽  
Chenlu Xu ◽  
Yuan Yuan ◽  
Pengfei Wang ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Early Stage ◽  
Eastern China ◽  
Sedimentary Environment ◽  
Gas Production ◽  
Bohai Bay ◽  
Calcareous Shale ◽  
Shahejie Formation ◽  
Scanning Electron

Research on shale lithofacies is important for shale oil and gas production. This study focused on the lower third member of the Shahejie Formation ([Formula: see text]) in the Luo-69 well in the Zhanhua Sag, Jiyang Depression, Bohai Bay Basin, eastern China. Several methods, including thin section observations, total organic carbon (TOC) analysis, X-ray diffraction analysis, quantitative evaluations of minerals by scanning electron microscopy, major and trace-element analyses, and field emission-scanning electron microscopy, are used to investigate the effect of sedimentary environment on the type and distribution of shale lithofacies. Our research indicates that 36 types of shale lithofacies can be classified based on the TOC content, mineral composition, and sedimentary structure, of which five types are identified in the study area. The [Formula: see text] shale has a high calcareous mineral content (average of 49.64%), low clay and siliceous minerals contents (averages of 19.54% and 19.02%, respectively), a high TOC content (average of 3.00 wt%), and well-developed horizontal bedding. The sedimentary environment during the deposition of the [Formula: see text] shale in the Zhanhua Sag had a warm and moist climate, limited provenance, saline water, and strong reducibility. The sedimentary environment in the early stage had a drier climate, more limited provenance, higher salinity, and stronger reducibility than that in the later stage. Shale lithofacies can reflect a certain sedimentary environment and depositional process; similarly, a depositional environment controls the type and distribution of shale lithofacies. Due to the characteristics of the [Formula: see text] sedimentary environment, organic-rich massive mixed shale, organic-rich bedded mixed-calcareous shale, organic-rich laminated calcareous shale, and organic-fair laminated calcareous shale are developed in the [Formula: see text] formation from top to bottom.

scholarly journals In Vitro Effect of Modified Polyetheretherketone (PEEK) Implant Abutments on Human Gingival Epithelial Keratinocytes Migration and Proliferation

Materials ◽  
2019 ◽  
Vol 12 (9) ◽  
pp. 1401 ◽  
Author(s):  
Liza L. Ramenzoni ◽  
Thomas Attin ◽  
Patrick R. Schmidlin
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Tetrazolium Salt ◽  
Microscopy Imaging ◽  
Implant Abutments ◽  
And Migration ◽  
Vitro Effect ◽  
Scanning Electron ◽  
Proliferation And Migration

Improving soft tissue attachment to implant abutments is a crucial factor for enduring health and maintenance of soft peri-implant tissue health. In this in vitro study we aimed to compare the biocompatibility of three different abutment surfaces: titanium, zirconia and modified polyetheretherketone (PEEK). Surface topography, roughness and wettability were investigated with scanning electron microscopy, profilometer and contact angle meter, respectively. Human gingival epithelial keratinocytes were examined for viability, morphology, proliferation and migration by using tetrazolium salt colorimetric assay, scanning electron microscopy imaging, immunofluorescence bromodeoxyuridine analysis and scratch wound healing assays. Roughness measurements revealed differences between the investigated surfaces. Keratinocytes cultured on all examined surfaces indicated adhesion and attachment by means of scanning electron microscopy imaging. Cell viability assays showed no significant differences between the groups (p > 0.05). The modified PEEK surface similarly improved surface roughness in comparison to titanium and zirconia, which resulted in greater and equivalent cell proliferation and migration. The study methodology showed here may emphasize the importance of cell interactions with different abutment materials, which in part increases the changes of implant success. PEEK, titanium and zirconia surface types used in this study showed mostly similar epithelial biological responses.

Facile Synthesis of LnPO4: Tb (Ln = Ce, Gd) Green Emission Phosphors at Specific Temperature (80 or 680°С)

2012 ◽  
Vol 442 ◽  
pp. 3-7
Author(s):  
Qian Ming Wang ◽  
Zheng Yang Zhang ◽  
Yan Li
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Crystal Growth ◽  
Green Emission ◽  
X Ray Diffraction ◽  
Facile Synthesis ◽  
X Ray ◽  
Specific Temperature ◽  
Temperature Scanning ◽  
Scanning Electron

Cerium and gadolinium phosphate micro-meter size phosphors with average diameters of 20-50 μM were prepared. X-Ray Diffraction (XRD) data confirmed the crystalline phases of samples could be formed at different temperature. Scanning electron microscopy (SEM) investigated the morphology and crystalline of the samples, showing that many regular and large pores (100-200 μM) were dispersed within the micro-meter scale composites. We have proved the above crystal growth structures were controllable and predicable based on the current conditions.

Sign in / Sign up

Export Citation Format

Share Document