Article
Chemistry, Physical
Liwei Wang, Lewis Rothberg
Summary: Photophysical properties of conjugated polymers are strongly influenced by chain morphology and interchain interactions. Characteristic spectra of poly[(9,9-dioctylfluorenyl-2,7-diyl)-alt-co-(bithiophene)] (F8T2) in single-chain and bulk cases exhibit differences in fluorescence dynamics and intensities. Care must be taken when drawing conclusions about single-chain spectra based on bulk data.
JOURNAL OF PHYSICAL CHEMISTRY B
(2021)
Article
Chemistry, Physical
Feng Wang, Shawkat Islam, Christopher T. Chantler
Summary: This study investigates the impact of solvents on the configuration and energy components of ferrocene through a combination of theoretical calculations and experimental measurements. The results indicate that the polarity of the solvent has a small effect on the relative energies of the rotamers of Fc, but significantly alters the electrostatic and Pauli energy contributions to Fc conformers.
RADIATION PHYSICS AND CHEMISTRY
(2021)
Article
Polymer Science
Kefeng Zhao, Qiang Zhang, Liang Chen, Tao Zhang, Yanchun Han
Summary: By controlling the side chain ordering and backbone planarization processes, we successfully prepared P(NDI2OD-T2) conjugated polymer nanowires. This method allows the nucleation pathway to be controlled using selective solvents, thereby altering the final film morphology.
Article
Chemistry, Multidisciplinary
Philip Schafer, Christiaan de Vet, Leire Gartzia-Rivero, Guillaume Raffy, Min-Tzu Kao, Christian Schafer, Laura J. Romasanta, Bertrand Pavageau, Yu-Tang Tsai, Lionel Hirsch, Dario M. Bassani, Andre Del Guerzo
Summary: In this study, the self-assembly of an n-type anthracene derivative and a p-type tetracene derivative into nano-ribbons was investigated. It was found that the nano-ribbons exhibited narcissistic self-sorting behavior, emitting different colors depending on the growth solvent. The self-sorting behavior was proposed to originate from the discrepancy between the quadrupolar character of the n-type derivative and the dipolar character of the p-type derivative. Inter-ribbon FRET and electro-luminescence switch-on were observed at the p-n junctions of the nano-ribbons.
Article
Chemistry, Physical
Ivan F. F. Antipov, Anatoly I. I. Ivanov
Summary: A model of symmetry breaking charge separation in symmetric excited dyads and dimers is presented. The model includes at least four basis electronic states with electronic couplings between them. The study shows that the degree of charge separation can be controlled by adjusting the model parameters, and the predictions of the model agree with experimental data.
JOURNAL OF CHEMICAL PHYSICS
(2022)
Article
Geosciences, Multidisciplinary
Wei Yan, Yanyao Zhang, Yunlu Ma, Mingyue He, Lifei Zhang, Weidong Sun, Christina Yan Wang, Xi Liu
Summary: A series of coesite was synthesized under high temperature and pressure, with studies conducted on major and trace elements, water contents, and hydrogen defects. Results show the existence of a hydrogen-incorporation mechanism H+ + B3+ <-> Si4+ in coesite, while the previously proposed mechanism H+ Al3+ <-> Si4+ does not function.
GEOSCIENCE FRONTIERS
(2021)
Article
Geography, Physical
Martin Petr Janovsky, Jan Horak, Oren Ackermann, Aharon Tavger, Deborah Cassuto, Ladislav Smejda, Michal Hejcman, Yaakov Anker, Itzhaq Shai
Summary: This study utilized POSL, granulometry, and PXRF to investigate sedimentary processes and chemical compositions in the archaeological site of Tel Burna. The results revealed a gradual accumulation of sediment inside the casemate wall over a long period of time, while sediment outside the wall was deposited in a one-time event. The PXRF analysis showed a correlation between human activities and certain chemical elements, allowing for pseudo-dating of strata and distinguishing natural and anthropogenic processes.
QUATERNARY INTERNATIONAL
(2022)
Article
Chemistry, Physical
Junjie Zou, Shifeng Xiao, Carlos Simmerling, Daniel P. Raleigh
Summary: Proteins fold on smooth free energy landscapes biased toward the native state, but even rapidly folding proteins can experience roughness on their landscapes. The interactions in the denatured state ensemble under native conditions are challenging to quantify, and non-native interactions can stabilize native backbone structure in the ensemble. Computational and experimental approaches can provide insight into these interactions that cannot be obtained with either method alone.
JOURNAL OF PHYSICAL CHEMISTRY B
(2021)
Article
Biochemistry & Molecular Biology
Karl Kochanowski, Hiroyuki Okano, Vadim Patsalo, James Williamson, Uwe Sauer, Terence Hwa
Summary: This study identifies the regulatory mechanisms that coordinate catabolism and anabolism in Escherichia coli, showing that a simple global gene regulatory program mainly implemented by the transcription factor Crp plays a crucial role in allocating proteomic resources and adjusting metabolic fluxes. In addition, passive changes in local metabolite concentrations contribute to the robust coordination of individual metabolic reactions.
MOLECULAR SYSTEMS BIOLOGY
(2021)
Article
Multidisciplinary Sciences
Albert L. Mueller, Wenyu Gu, Vadim Patsalo, Jorg S. Deutzmann, James R. Williamson, Alfred M. Spormann
Summary: The study systematically characterized the physiology of Methanococcus maripaludis during slow growth under energy-limiting conditions, revealing a different resource allocation strategy compared to commonly studied versatile chemoheterotrophic bacteria. Despite slow growth, the methanogenic archaeon maintained its maximum methanogenesis capacity over a wide range of growth rates, with adjustments in energy usage and maintenance energy per biomass.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2021)
Article
Biochemistry & Molecular Biology
Ming-Hao Li, Lakshan Manathunga, Erwin London, Daniel P. Raleigh
Summary: The fluorescent dye DPH interacts with amyloid fibrils formed by h-amylin, resulting in increased fluorescence. The time course of amyloid formation can be monitored using DPH, and it may be useful for studying mutant amyloids.
Article
Chemistry, Physical
Junjie Zou, Zhipeng Li, Shuai Liu, Chunwang Peng, Dong Fang, Xiao Wan, Zhixiong Lin, Tai-Sung Lee, Daniel P. Raleigh, Mingjun Yang, Carlos Simmerling
Summary: In drug discovery, altering drug compound structures to improve binding affinity and properties is common. This study presents a new method for simulating the challenging process of "scaffold hopping", demonstrating high accuracy in modeling linker contraction or expansion.
JOURNAL OF CHEMICAL THEORY AND COMPUTATION
(2021)
Article
Chemistry, Multidisciplinary
Ming-Hao Li, Daniel P. Raleigh, Erwin London
Summary: The natural asymmetry of cellular membranes affects their properties. Methods involving cyclodextrin have been developed for preparing asymmetric vesicles, enhancing their resistance to leakage and improving stability.
Correction
Biochemistry & Molecular Biology
Ming-Hao Li, Lakshan Manathunga, Erwin London, Daniel P. Raleigh
Article
Microbiology
Ravi Chawla, Steven Klupt, Vadim Patsalo, James R. Williamson, Lisa R. Racki
Summary: The protein AlgP is found to be associated with polyP granules and is required for their even spacing. AlgP binds to the chromosome and inhibits fusion between polyP granules, resulting in their evenly spaced distribution. This discovery provides insights into the functional significance of granule organization during starvation.
Article
Endocrinology & Metabolism
Joseph J. Castillo, Alfred C. Aplin, Daryl J. Hackney, Meghan F. Hogan, Nathalie Esser, Andrew T. Templin, Rehana Akter, Steven E. Kahn, Daniel P. Raleigh, Sakeneh Zraika, Rebecca L. Hull
Summary: The study found that aggregation of IAPP is toxic to islet endothelial cells and induces inflammatory responses, resulting in decreased capillary density, increased capillary diameter, and an increased number of pericytes.
Article
Biochemistry & Molecular Biology
Lakshan Manathunga, Alexander Zhyvoloup, Aria Baghai, Daniel P. Raleigh
Summary: Islet amyloid polypeptide (IAPP) is a 37-residue polypeptide hormone secreted by pancreatic β-cells. It plays a role in glycemic regulation, but in the pre-type-2 diabetic state, it forms amyloid aggregates that contribute to β-cell dysfunction and disease progression. This study investigates the role of aromatic residues in modulating the time course of amyloid formation and cytotoxicity. The results reveal that F23 plays a dominant role and has both accelerating and slowing effects on amyloid formation, as well as influences toxicity.
Article
Biochemistry & Molecular Biology
Matthew E. T. Miller, Ming-Hao Li, Aria Baghai, Vincent H. Peetz, Alexander Zhyvoloup, Daniel P. Raleigh
Summary: Human islet amyloid polypeptide (hIAPP) plays a significant role in the development of diabetes and beta-cell dysfunction. Sheep and goat IAPP have low amyloid formation and toxicity compared to hIAPP. Studying IAPP from different species can provide insights for designing soluble analogues of the human peptide.
Article
Chemistry, Analytical
Konstantinos Thalassinos, Charles Eldrid, Tristan Cragnolini, Aisha Ben-Younis, Junjie Zou, Daniel P. . Raleigh
Summary: Native mass spectrometry combined with ion mobility and collisional activation is an important method for studying protein unfolding. By using unbiased molecular dynamics simulations, the in vacuo unfolding behavior of a well-studied protein, N-terminal domain of ribosomal L9, was found to replicate the behavior observed in solution. However, the theoretical collision cross section of the simulations was slightly lower than that of the experimental data, possibly due to reduced sampling.
ANALYTICAL CHEMISTRY
(2022)
Review
Biochemistry & Molecular Biology
Sanem Ayaz Kok, Selcen Ustun, Humeyra Taskent Sezgin
Summary: Infectious diseases in the livestock industry pose major challenges to animal health, food safety, and the economy, as well as a significant threat to human populations through zoonotic diseases. These diseases are of great concern and listed as notifiable by the World Organization for Animal Health (OIE). Utilizing rapid diagnostic methods like loop-mediated isothermal amplification (LAMP), infectious diseases can be effectively controlled in herds. LAMP is a simple and rapid nucleic acid amplification method that has been widely studied for its potential in field detection of various infectious diseases.
MOLECULAR BIOTECHNOLOGY
(2023)
Article
Biochemistry & Molecular Biology
Lakshan Manathunga, Rehana Akter, Alexander Zhyvoloup, Carlos Simmerling, Daniel P. P. Raleigh
Summary: Amyloids are protein deposits implicated in various diseases. Disrupting the tight packing in amyloid fibrils affects their formation kinetics. Substitutions with larger amino acids disrupt packing and destabilize fibril structures, while specific substitutions can enhance or slow down amyloid formation.
Article
Biochemical Research Methods
Henry M. Sanders, Farzaneh Chalyavi, Caitlyn R. Fields, Marius M. Kostelic, Ming-Hao Li, Daniel P. Raleigh, Martin T. Zanni, Michael T. Marty
Summary: The aggregation of islet amyloid polypeptide (IAPP) is associated with beta-cell dysfunction in type 2 diabetes (T2D) in humans. The interaction of IAPP oligomers with lipid membranes can disrupt the bilayer integrity and/or homeostasis of the cell. Amino acid sequence variations of IAPPs between species can greatly decrease their propensity for aggregation.
JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY
(2023)