Protein structural transitions and their functional role

2004 ◽  
Vol 363 (1827) ◽  
pp. 331-356 ◽  
Author(s):  
Martin Karplus ◽  
Yi Qin Gao ◽  
Jianpeng Ma ◽  
Arjan van der Vaart ◽  
Wei Yang
Keyword(s):  
Escherichia Coli ◽  
Protein Folding ◽  
Functional Role ◽  
Motor Protein ◽  
Molecular Machines ◽  
Living Cells ◽  
The Other ◽  
Theoretical Studies ◽  
Structural Transitions ◽  
Experimental And Theoretical Studies

Living cells are a collection of molecular machines which carry out many of the functions essential for the cell's existence, differentiation and reproduction. Most, though not all, of these machines are made up of proteins. Because of their complexity, an understanding of how they work requires a synergistic combination of experimental and theoretical studies. In this paper we outline our studies of two such protein machines. One is GroEL, the chaperone from Escherichia coli , which aids in protein folding; the other is F 1 –ATPase, a motor protein which synthesizes and hydrolyses ATP.

Experimental and Theoretical Studies of Protein Folding-Unfolding

2004 ◽  
Vol 51 (5B) ◽  
pp. 1161-1173 ◽  
Author(s):  
Y. J. Shiu ◽  
Catherlene Su ◽  
Y. L. Yeh ◽  
K. K. Liang ◽  
M. Hayashi ◽  
...  
Keyword(s):  
Protein Folding ◽  
Theoretical Studies ◽  
Experimental And Theoretical Studies

A highly selective and sensitive fluorescent turn-on Al3+ chemosensor in aqueous media and living cells: experimental and theoretical studies

2016 ◽  
Vol 40 (1) ◽  
pp. 171-178 ◽  
Author(s):  
In Hong Hwang ◽  
Ye Won Choi ◽  
Kyung Beom Kim ◽  
Gyeong Jin Park ◽  
Jae Jun Lee ◽  
...  
Keyword(s):  
Aqueous Media ◽  
Living Cells ◽  
Fluorescent Chemosensor ◽  
Theoretical Studies ◽  
Enhanced Fluorescence ◽  
Turn On ◽  
Experimental And Theoretical Studies

A highly selective and sensitive fluorescent chemosensor exhibited enhanced fluorescence in the presence of Al3+ and in living cells.

Preparation of Nanoporous Poly(Methyl Silsesquioxanes) Films Using PS-b-P4VP as Template

2008 ◽  
Vol 8 (3) ◽  
pp. 1537-1544 ◽  
Author(s):  
Yang-Yen Yu ◽  
Chang-Chung Yang
Keyword(s):  
Hydrogen Bonding ◽  
The Other ◽  
Theoretical Studies ◽  
Intermolecular Hydrogen Bonding ◽  
Pore Morphology ◽  
Nanoporous Films ◽  
Vinyl Pyridine ◽  
Loading Ratio ◽  
Copolymer Poly ◽  
Experimental And Theoretical Studies

Nanoporous poly(methyl silsesquioxane) (PMSSQ) film was prepared through the templating of an amphiphilic block copolymer, poly(styrene-4-vinyl pyridine) (PS-b-P4VP). The experimental and theoretical studies suggest that the intermolecular hydrogen bonding is existed between the PMSSQ precursor and PS-b-P4VP. The miscible hybrid and the narrow thermal decomposition of the PS-b-P4VP lead to nanopores in the prepared films from the results of TGA, AFM, and TEM. The effects of the loading ratio on the morphology and properties of the prepared nanoporous PMSSQ films were investigated. The TEM and AFM studies show that the uniform pore morphology with pore size 10–15 nm can be prepared from a modest porogen loading level for the optimum intermolecular hydrogen bonding. The refractive index and dielectric constant of the prepared nanoporous films decreases with an increase in PS-b-P4VP loading. On the other hand, the porosity increases with an increasing PS-b-P4VP loading. This study demonstrates a methodology to control pore morphology and properties of the nanoporous PMSSQ films through the templating of PS-b-P4VP.

A dual chemosensor for Zn 2+ and Co 2+ in aqueous media and living cells: Experimental and theoretical studies

2016 ◽  
Vol 223 ◽  
pp. 509-519 ◽  
Author(s):  
Gyeong Jin Park ◽  
Jae Jun Lee ◽  
Ga Rim You ◽  
LeTuyen Nguyen ◽  
Insup Noh ◽  
...  
Keyword(s):  
Aqueous Media ◽  
Living Cells ◽  
Theoretical Studies ◽  
Experimental And Theoretical Studies

The Role of Chloride in the Corrosion Caused by Flue Gases and Their Deposits

1971 ◽  
Vol 93 (3) ◽  
pp. 307-312 ◽  
Author(s):  
A. J. B. Cutler ◽  
W. D. Halstead ◽  
J. W. Laxton ◽  
C. G. Stevens
Keyword(s):  
Gas Turbines ◽  
The Other ◽  
Flue Gases ◽  
Theoretical Studies ◽  
Other Hand ◽  
Experimental And Theoretical Studies ◽  
High Chloride ◽  
Plant Components

The role of chloride in the corrosion of oil- and coal-fired boilers and gas turbines, by flue gases and their deposits, is discussed, on the basis of both experimental and theoretical studies. It is concluded that in most boilers, the presence of chloride in the fuel will not result in any serious increase in the rate of corrosion of plant components. On the other hand, a number of situations are identified, which can arise in both boilers and gas turbines, in which high chloride levels in the fuel can be associated with enhanced rates of corrosion.

scholarly journals How kinesin waits for ATP affects the nucleotide and load dependence of the stepping kinetics

2019 ◽  
Vol 116 (46) ◽  
pp. 23091-23099 ◽  
Author(s):  
Ryota Takaki ◽  
Mauro L. Mugnai ◽  
Yonathan Goldtzvik ◽  
D. Thirumalai
Keyword(s):  
Experimental Testing ◽  
The Other ◽  
Theoretical Studies ◽  
Resistive Force ◽  
Load Dependence ◽  
Experimental Observable ◽  
Conventional Kinesin ◽  
Key Steps ◽  
Directional Transport ◽  
Experimental And Theoretical Studies

Conventional kinesin, responsible for directional transport of cellular vesicles, takes multiple nearly uniform 8.2-nm steps by consuming one ATP molecule per step as it walks toward the plus end of the microtubule (MT). Despite decades of intensive experimental and theoretical studies, there are gaps in the elucidation of key steps in the catalytic cycle of kinesin. How the motor waits for ATP to bind to the leading head is controversial. Two experiments using a similar protocol have arrived at different conclusions. One asserts that kinesin waits for ATP in a state with both the heads bound to the MT, whereas the other shows that ATP binds to the leading head after the trailing head detaches. To discriminate between the 2 scenarios, we developed a minimal model, which analytically predicts the outcomes of a number of experimental observable quantities (the distribution of run length, the distribution of velocity [P(v)], and the randomness parameter) as a function of an external resistive force (F) and ATP concentration ([T]). The differences in the predicted bimodality in P(v) as a function of F between the 2 models may be amenable to experimental testing. Most importantly, we predict that the F and [T] dependence of the randomness parameters differ qualitatively depending on the waiting states. The randomness parameters as a function of F and [T] can be quantitatively measured from stepping trajectories with very little prejudice in data analysis. Therefore, an accurate measurement of the randomness parameter and the velocity distribution as a function of load and nucleotide concentration could resolve the apparent controversy.

Infection of Escherichia coli with bacteriophages

1969 ◽  
Vol 27 ◽  
pp. 370-371
Author(s):  
Manfred E. Bayer
Keyword(s):  
Escherichia Coli ◽  
Nucleic Acid ◽  
Cell Surface ◽  
Virus Type ◽  
Infection Process ◽  
Adsorption Site ◽  
The Other ◽  
Specific Receptors ◽  
Bacterial Receptors

The first step in the infection of a bacterium by a virus consists of a collision between cell and bacteriophage. The presence of virus-specific receptors on the cell surface will trigger a number of events leading eventually to release of the phage nucleic acid. The execution of the various "steps" in the infection process varies from one virus-type to the other, depending on the anatomy of the virus. Small viruses like ØX 174 and MS2 adsorb directly with their capsid to the bacterial receptors, while other phages possess attachment organelles of varying complexity. In bacteriophages T3 (Fig. 1) and T7 the small conical processes of their heads point toward the adsorption site; a welldefined baseplate is attached to the head of P22; heads without baseplates are not infective.

The Nature of the Intramembrane Particle

1980 ◽  
Vol 38 ◽  
pp. 688-691
Author(s):  
A.J. Verkleij
Keyword(s):  
Escherichia Coli ◽  
Tight Junction ◽  
Gap Junction ◽  
The Other ◽  
Fracture Face ◽  
Band 3 Protein ◽  
Satisfactory Explanation ◽  
Freeze Fracturing ◽  
Intramembrane Particle ◽  
Luminal Membrane

Freeze-fracturing splits membranes into two helves, thus allowing an examination of the membrane interior. The 5-10 rm particles visible on both monolayers are widely assumed to be proteinaceous in nature. Most membranes do not reveal impressions complementary to particles on the opposite fracture face, if the membranes are fractured under conditions without etching. Even if it is considered that shadowing, contamination or fracturing itself might obscure complementary pits', there is no satisfactory explanation why under similar physical circimstances matching halves of other membranes can be visualized. A prominent example of uncomplementarity is found in the erythrocyte manbrane. It is wall established that band 3 protein and possibly glycophorin represents these nonccmplanentary particles. On the other hand a number of membrane types show pits opposite the particles. Scme well known examples are the ";gap junction',"; tight junction, the luminal membrane of the bladder epithelial cells and the outer membrane of Escherichia coli.

Sign in / Sign up

Export Citation Format

Share Document