Microindentation Hardness of Protein Crystals under Controlled Relative Humidity

A new crystallization system is described, which makes it possible to use an evaporation-based microfluidic crystallization technique for protein crystallization. The gas and water permeability of the used polydimethylsiloxane (PDMS) material enables evaporation of the protein solution in the microfluidic device. The rates of evaporation are controlled by the relative humidity conditions, which are adjusted in a precise and stable way by using saturated solutions of different reagents. The protein crystals could nucleate and grow under different relative humidity conditions. Using this method, crystal growth could be improved so that approximately 1 mm-sized lysozyme crystals were obtained more successfully than using standard methods. The largest lysozyme crystal obtained reached 1.57 mm in size. The disadvantage of the good gas permeability in PDMS microfluidic devices becomes an advantage for protein crystallization. The radius distributions of aggregrates in the solutions inside the described microfluidic devices were derived fromin situdynamic light scattering measurements. The experiments showed that the environment inside of the microfluidic device is more stable than that of conventional crystallization techniques. However, the morphological results showed that the protein crystals grown in the microfluidic device could lose their morphological stability. Air bubbles in microfluidic devices play an important role in the evaporation progress. A model was constructed to analyze the relationship of the rates of evaporation and the growth of air bubbles to the relative humidity.

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Sectioned rubisco crystals in TEM

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010016087x ◽

1990 ◽

Vol 48 (3) ◽

pp. 664-665

Author(s):

Gunnel Karlsson ◽

Jan-Olov Bovin ◽

Michael Bosma

Keyword(s):

Plant Cell ◽

Carbon Fixation ◽

Unit Cell ◽

Protein Crystals ◽

Unit Cell Parameters ◽

Cell Parameters ◽

Photosynthetic Carbon Fixation ◽

Photosynthetic Carbon

RuBisCO (D-ribulose-l,5-biphosphate carboxylase/oxygenase) is the most aboundant enzyme in the plant cell and it catalyses the key carboxylation reaction of photosynthetic carbon fixation, but also the competing oxygenase reaction of photorespiation. In vitro crystallized RuBisCO has been studied earlier but this investigation concerns in vivo existance of RuBisCO crystals in anthers and leaves ofsugarbeets. For the identification of in vivo protein crystals it is important to be able to determinethe unit cell of cytochemically identified crystals in the same image. In order to obtain the best combination of optimal contrast and resolution we have studied different staining and electron accelerating voltages. It is known that embedding and sectioning can cause deformation and obscure the unit cell parameters.

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Dynamical Scattering in Electron Diffraction of wet Protein Crystals

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s1431927600000167 ◽

1980 ◽

Vol 38 ◽

pp. 42-43

Author(s):

B. B. Chang ◽

D. F. Parsons

Keyword(s):

Electron Diffraction ◽

Scattering Theory ◽

Protein Crystals ◽

Electron Diffraction Data ◽

Specimen Thickness ◽

Major Question ◽

X Ray ◽

Scattering Effects ◽

Diffraction Patterns ◽

Acceleration Voltage

The significance of dynamical scattering effects remains the major question in the structural analysis by electron diffraction of protein crystals preserved in the hydrated state. In the few cases (single layers of purple membrane and 400-600 Å thick catalase crystals examined at 100 kV acceleration voltage) where electron-diffraction patterns were used quantitatively, dynamical scattering effects were considered unimportant on the basis of a comparison with x-ray intensities. The kinematical treatment is usually justified by the thinness of the crystal. A theoretical investigation by Ho et al. using Cowley-Moodie multislice formulation of dynamical scattering theory and cytochrome b5as the test object2 suggests that kinematical analysis of electron diffraction data with 100-keV electrons would not likely be valid for specimen thickness of 300 Å or more. We have chosen to work with electron diffraction patterns obtained from actual wet protein crystals (rat hemoglobin crystals of thickness range 1000 to 2500 Å) at 200 and 1000 kV and to analyze these for dynamical effects.

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Effect of relative humidity on the rate of dissolution of aluminium in iodine-methanol solution

Journal of Biochemical Toxicology ◽

10.1002/jbt.2570091004 ◽

1959 ◽

Vol 9 (10) ◽

pp. 519-520

Author(s):

D. F. Maclennan

Keyword(s):

Relative Humidity ◽

Methanol Solution ◽

Rate Of Dissolution

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168. Prediction of the Effect of High Relative Humidity on Organic Vapor Cartridge Performance

10.3320/1.2765684 ◽

2001 ◽

Author(s):

E. Johnson ◽

L. Brey

Keyword(s):

Relative Humidity ◽

High Relative Humidity ◽

Organic Vapor

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EPIDEMIOLOGY, ECOLOGY AND PREVALENCE OF SOIL TRANSMITTED HELMINTHS FROM KOSHI REGION OF NORTH BIHAR.

FLORA AND FAUNA ◽

10.33451/florafauna.v24i1pp155-162 ◽

2018 ◽

Vol 24 (1) ◽

Author(s):

LAKSHMI CHOUDHARY ◽

PRABHAWATI PRABHAWATI

Keyword(s):

Relative Humidity ◽

Ascaris Lumbricoides ◽

Rainy Season ◽

Climatic Factors ◽

Trichuris Trichiura ◽

Hookworm Infection ◽

Soil Transmitted Helminths ◽

High Incidence ◽

Apparently Healthy

Prevalence of soil transmitted helminthes infections in apparently healthy school going children and other 528 people of different districts of Koshi regions of North Bihar were evaluated. Over all incidences of STHs infection was 39.39% during study. High incidence of STH was seen in the rainy season i.e., in the month of July and August, September, significantly higher (P<0.05) .The incidence of Ascaris lumbricoides was highest in the month of August (18.64%). The month of September was 15.25% followed by that of July (14.4%) and October with 10.16%. Also the incidence of hookworm registered the highest incidence in the month of June (19.27%) and lowest in the month of December (4.82%) during the study period. However prevalence of Trichuris trichiura was negligible and it was almost nil in the most of the months but was highest in month of September with 28.57% and lowest in October with 14.00% The climatic factors are responsible for soil transmitted helminthes which are temperature, rainfall and relative humidity. Ascariasis, Trichuriasis and Ancyclostomiasis (Hookworm infection) are found to be endemic in this region.

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EL NINO RELATED CLIMATE AND DENGUE FEVER CASES IN JEDDAH, SAUDI ARABIA

FLORA AND FAUNA ◽

10.33451/florafauna.v25i1pp91-99 ◽

2019 ◽

Vol 25 (1) ◽

Author(s):

MASROOR ALI KHAN ◽

KHALID AL GHAMDI ◽

JAZEM A. MEHYOUB ◽

RAKHSHAN KHAN

Keyword(s):

Relative Humidity ◽

Dengue Fever ◽

El Niño ◽

Significant Relationship ◽

El Nino ◽

Climate Data ◽

Light Traps ◽

Mosquito Abundance ◽

Dengue Transmission ◽

The Relationship

The focus of this study is to find the relationship between El Nino and dengue fever cases in the study area.Mosquito density was recorded with the help of light traps and through aspirators collection. Climate data were obtained from National Meteorology and Environment centre. (Year wise El Nino and La Nina data are according to NOAA & Golden Gate Weather Services). Statistical methods were used to establish the correlation coefficient between different factors. A high significant relationship was observed between Relative Humidity and Dengue fever cases, but Aedes abundance had no significant relationship with either Relative humidity and Temperature. Our conclusion is that the El Nino does not affect the dengue transmission and Aedes mosquito abundance in this region, which is supported by earlier works.

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