Frontispiz: Racemic Monomer‐Based One‐Handed Helical Polymer Recognizes Enantiomers through Auto‐Evolution of Its Helical Handedness Excess

The RecA protein of E. coli has been shown to mediate genetic recombination, regulate its own synthesis, control the expression of other genes, act as a specific protease, form a helical polymer and have an ATPase activity, among other observed properties. The unusual filament formed by the RecA protein on DNA has not previously been shown to exist outside of bacteria. Within this filament, the 36 Å pitch of B-form DNA is extended to about 95 Å, the pitch of the RecA helix. We have now establishedthat similar nucleo-protein complexes are formed by bacteriophage and yeast proteins, and availableevidence suggests that this structure is universal across all of biology, including humans. Thus, understanding the function of the RecA protein will reveal basic mechanisms, in existence inall organisms, that are at the foundation of general genetic recombination and repair.Recombination at this moment is assuming an importance far greater than just pure biology. The association between chromosomal rearrangements and neoplasms has become stronger and stronger, and these rearrangements are most likely products of the recombinatory apparatus of the normal cell. Further, damage to DNA appears to be a major cause of cancer.

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SuFExable Polymers with Helical Structures Derived from Thionyl Tetrafluoride (SOF4)

10.26434/chemrxiv.10005758 ◽

2019 ◽

Author(s):

Suhua Li ◽

Gencheng Li ◽

Bing Gao ◽

Sidharam P. Pujari ◽

Xiaoyan Chen ◽

...

Keyword(s):

Functional Polymers ◽

Polymer Chains ◽

New Materials ◽

Helical Structures ◽

Polymer Backbone ◽

Silyl Ethers ◽

Helical Polymer ◽

Key Characteristics ◽

Post Modification ◽

Individual Polymer

The first SuFEx click chemistry synthesis of SOF<sub>4</sub>-derived copolymers based upon the polymerization of bis(iminosulfur oxydifluorides) and bis(aryl silyl ethers) is described. This novel class of SuFEx polymer presents two key characteristics: First, the newly created [-N=S(=O)F-O-] polymer backbone linkages are themselves SuFExable and primed to undergo further high-yielding and precise SuFEx-based post-modification with phenols or amines to yield branched functional polymers. Second, studies of individual polymer chains of several of these new materials indicate the presence of helical polymer structures, which itself suggests a preferential approach of new monomers onto the growing polymer chain upon the formation of the stereogenic linking moiety.

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Chiral Helical Polymer/Perovskite Hybrid Nanofibers with Intense Circularly Polarized Luminescence

ACS Nano ◽

10.1021/acsnano.1c00864 ◽

2021 ◽

Vol 15 (4) ◽

pp. 7463-7471

Author(s):

Biao Zhao ◽

Xiaobin Gao ◽

Kai Pan ◽

Jianping Deng

Keyword(s):

Circularly Polarized ◽

Helical Polymer ◽

Hybrid Nanofibers ◽

Circularly Polarized Luminescence ◽

Polarized Luminescence

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Hyperpolarizability of Helical Polymer Molecules and the Sampling of the ir‐Active Optical Phonon Dispersion Curves

The Journal of Chemical Physics ◽

10.1063/1.1671356 ◽

1969 ◽

Vol 50 (5) ◽

pp. 2244-2246 ◽

Cited By ~ 11

Author(s):

Bruno Fanconi ◽

Warner L. Peticolas

Keyword(s):

Optical Phonon ◽

Phonon Dispersion ◽

Dispersion Curves ◽

Phonon Dispersion Curves ◽

Polymer Molecules ◽

Helical Polymer

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Erratum to: `Order–disorder transitions and melting in a helical polymer crystal: molecular dynamics calculations of model poly(ethylene oxide)' [Chem. Phys. Lett. 385 (2004) 351–356]

Chemical Physics Letters ◽

10.1016/j.cplett.2004.04.072 ◽

2004 ◽

Vol 391 (1-3) ◽

pp. 200 ◽

Cited By ~ 1

Author(s):

M Krishnan ◽

S Balasubramanian

Keyword(s):

Molecular Dynamics ◽

Ethylene Oxide ◽

Chem Phys ◽

Helical Polymer ◽

Polymer Crystal ◽

Molecular Dynamics Calculations ◽

Poly Ethylene Oxide ◽

Poly Ethylene

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TELSAM polymers accelerate crystallization of fused target proteins by stabilizing minimal crystal contacts and in the absence of direct inter-TELSAM contacts

10.1101/2021.07.23.453529 ◽

2021 ◽

Author(s):

Supeshala Dilrukshi Sarath Nawarathnage ◽

Sara Soleimani ◽

Moriah H Mathis ◽

Braydan D Bezzant ◽

Diana T Ramírez ◽

...

Keyword(s):

Protein Crystallization ◽

Target Protein ◽

Protein Crystal ◽

Protein Fusion ◽

Definitive Evidence ◽

Helical Polymer ◽

Crystal Contacts ◽

Genetic Fusion ◽

Direct Inter ◽

Future Work

We extend investigation into the usefulness of genetic fusion to TELSAM polymers as an effective protein crystallization strategy. We tested various numbers of the target protein fused per turn of the TELSAM helical polymer and various TELSAM–target connection strategies. We provide definitive evidence that: 1. A TELSAM–target protein fusion can crystallize more rapidly than the same target protein alone, 2. TELSAM–target protein fusions can form well-ordered, diffracting crystals using either flexible or rigid TELSAM–target linkers, 3. Well-ordered crystals can be obtained when either 2 or 6 copies of the target protein are presented per turn of the TELSAM helical polymer, 4. The TELSAM polymers themselves need not directly contact one another in the crystal lattice, and 5. Fusion to TELSAM polymer confers immense avidity to stabilize exquisitely weak inter-target protein crystal contacts. We report features of TELSAM-target protein crystals and outline future work needed to define the requirements for reliably obtaining optimal crystals of TELSAM–target protein fusions.

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