Five axioms for the functional design of peptide-based polymers as molecular machines and materials: Principle for macromolecular assemblies

Abstract Proteasomes are the principal molecular machines for the regulated degradation of intracellular proteins. These self-compartmentalized macromolecular assemblies selectively degrade misfolded, mistranslated, damaged or otherwise unwanted proteins, and play a pivotal role in the maintenance of cellular proteostasis, in stress response, and numerous other processes of vital importance. Whereas the molecular architecture of the proteasome core particle (CP) is universally conserved, the unfoldase modules vary in overall structure, subunit complexity, and regulatory principles. Proteasomal unfoldases are AAA+ ATPases (ATPases associated with a variety of cellular activities) that unfold protein substrates, and translocate them into the CP for degradation. In this review, we summarize the current state of knowledge about proteasome – unfoldase systems in bacteria, archaea, and eukaryotes, the three domains of life.

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Real-Time Interactive Visualisation of Large Macromolecular Assemblies and Molecular Machines at Atomic Resolution

Biophysical Journal ◽

10.1016/j.bpj.2016.11.984 ◽

2017 ◽

Vol 112 (3) ◽

pp. 178a ◽

Cited By ~ 1

Author(s):

David Sehnal ◽

Mandar Deshpande ◽

Radka Svobodova Varekova ◽

Saquib Mir ◽

Karel Berka ◽

...

Keyword(s):

Real Time ◽

Molecular Machines ◽

Atomic Resolution ◽

Macromolecular Assemblies ◽

Interactive Visualisation

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Introduction to Cell Membranes at Molecular Resolution

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100070217 ◽

1978 ◽

Vol 36 (3) ◽

pp. 497-502

Author(s):

R.J. Barrnett

Keyword(s):

Cell Membranes ◽

International Federation ◽

Mountain Range ◽

Cellular Membranes ◽

Short History ◽

Biological Organization ◽

Macromolecular Assemblies ◽

The Past

This subject, is like observing the panorama of a mountain range, magnificent towering peaks, but it doesn't take much duration of observation to recognize that they are still in the process of formation. The mountains consist of approaches, materials and methods and the rocky substance of information has accumulated to such a degree that I find myself concentrating on the foothills in the foreground in order to keep up with the advance; the edifices behind form a wonderous, substantive background. It's a short history for such an accumulation and much of it has been moved by the members of the societies that make up this International Federation. My panel of speakers are here to provide what we hope is an interesting scientific fare, based on the fact that there is a continuum of biological organization from biochemical molecules through macromolecular assemblies and cellular membranes to the cell itself. Indeed, this fact explains the whole range of towering peaks that have emerged progressively during the past 25 years.

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Multimode light microscopy and fluorescence-based reagents as tools for the study of chemical and molecular dynamics of living cells and tissues

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100122496 ◽

1992 ◽

Vol 50 (1) ◽

pp. 418-419

Author(s):

D. L. Taylor

Keyword(s):

Living Cells ◽

Cellular Level ◽

Molecular Techniques ◽

Cellular Functions ◽

Macromolecular Assemblies ◽

Cell Functions ◽

Molecular Events ◽

Yield Information ◽

Full Knowledge ◽

Structural Methods

Cells function through the complex temporal and spatial interplay of ions, metabolites, macromolecules and macromolecular assemblies. Biochemical approaches allow the investigator to define the components and the solution chemical reactions that might be involved in cellular functions. Static structural methods can yield information concerning the 2- and 3-D organization of known and unknown cellular constituents. Genetic and molecular techniques are powerful approaches that can alter specific functions through the manipulation of gene products and thus identify necessary components and sequences of molecular events. However, full knowledge of the mechanism of particular cell functions will require direct measurement of the interplay of cellular constituents. Therefore, there has been a need to develop methods that can yield chemical and molecular information in time and space in living cells, while allowing the integration of information from biochemical, molecular and genetic approaches at the cellular level.

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Simplified Approach to Calculating Geometric Stiffness Properties of Tread Pattern Elements

Tire Science and Technology ◽

10.2346/1.2135265 ◽

2003 ◽

Vol 31 (3) ◽

pp. 132-158 ◽

Cited By ~ 6

Author(s):

R. E. Okonieski ◽

D. J. Moseley ◽

K. Y. Cai

Keyword(s):

Development Process ◽

Functional Design ◽

Simplified Approach ◽

Tire Industry ◽

Geometric Stiffness ◽

Stiffness Properties ◽

Engineering Parameters ◽

Net To Gross ◽

Significant Effort

Abstract The influence of tread designs on tire performance is well known. The tire industry spends significant effort in the development process to create and refine tread patterns. Creating an aesthetic yet functional design requires characterization of the tread design using many engineering parameters such as stiffness, moments of inertia, principal angles, etc. The tread element stiffness is of particular interest because of its use to objectively determine differences between tread patterns as the designer refines the design to provide optimum levels of performance. The tread designer monitors the change in stiffness as the design evolves. Changes to the geometry involve many attributes including the number of sipes, sipe depth, sipe location, block element edge taper, nonskid depth, area net-to-gross, and so forth. In this paper, two different formulations for calculating tread element or block stiffness are reviewed and are compared to finite element results in a few cases. A few simple examples are shown demonstrating the basic functionality that is possible with a numerical method.

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