Effective interactions between fluid membranes [PDF]
A self-consistent theory is proposed for the general problem of interacting undulating fluid membranes subject to the constraint that they do not interpenetrate. We implement the steric constraint via an exact functional integral representation, and through the use of a saddle-point approximation transform it into a novel effective steric potential ...
arxiv +1 more source
Steric interactions and out-of-equilibrium processes control the internal organization of bacteria [PDF]
Despite the absence of a membrane-enclosed nucleus, the bacterial DNA is typically condensed into a compact body - the nucleoid. This compaction influences the localization and dynamics of many cellular processes including transcription, translation, and cell division.
arxiv +1 more source
Long-range electrostatic interactions between like-charged colloids: steric and confinement effects [PDF]
Within the framework of a Modified Poisson-Boltzmann theory accounting for steric effects of microions, we prove analytically that the effective pair interactions between like-charge colloids immersed in a confined electrolyte are repulsive. Our approach encompasses and extends previously known results to the case of complete confinement, and further ...
arxiv +1 more source
Multiple solutions of steady-state Poisson-Nernst-Planck equations with steric effects [PDF]
Experiments measuring currents through single protein channels show unstable currents. Channels switch between 'open' or 'closed' states in a spontaneous stochastic process called gating. Currents are either (nearly) zero or at a definite level, characteristic of each type of protein, independent of time, once the channel is open.
arxiv +1 more source
Poisson-Nernst-Planck equations with steric effects - non-convexity and multiple stationary solutions [PDF]
We study the existence and stability of stationary solutions of Poisson-Nernst- Planck equations with steric effects (PNP-steric equations) with two counter-charged species. These equations describe steady current through open ionic channels quite well. The current levels in open ionic channels are known to switch between `open' or `closed' states in a
arxiv +1 more source
Chiral and Steric Effects in Ethane: A Next Generation QTAIM Interpretation [PDF]
We introduce a development of next generation quantum theory of atoms in molecules (NG-QTAIM) for an investigation of the chirality of ethane and discover a $Q_{\sigma}$ isomer in addition to $S_{\sigma}$ and $R_{\sigma}$ stereoisomers in the stress tensor trajectory $U_{\sigma}$-space. The $Q_{\sigma}$ isomer is defined to be a 'null-isomer' since the
arxiv +1 more source
On the equilibrium of the Poisson-Nernst-Planck-Bikermann model equipping with the steric and correlation effects [PDF]
The Poisson-Nernst-Planck-Bikermann (PNPB) model, in which the ions and water molecules are treated as different species with non-uniform sizes and valences with interstitial voids, can describe the steric and correlation effects in ionic solution neglected by the Poisson-Nernst-Planck and Poisson-Boltzmann theories with point charge assumption. In the
arxiv
Characterization of fungal carbonyl sulfide hydrolase belonging to clade D β‐carbonic anhydrase
Here, we performed a functional analysis of the fungal enzymes belonging to clade D of the β‐class carbonic anhydrase family (β‐D‐CA). The β‐D‐CAs in the basidiomycete Gloeophyllum trabeum and the ascomycete Trichoderma harzianum showed very low activity in the hydration of CO2 but exhibited high activity in the hydrolysis of carbonyl sulfide (COS ...
Ryuka Iizuka+6 more
wiley +1 more source
LHCPs are transported to the thylakoid membrane via the (cp)SRP pathway. This process involves a transit complex of (cp)SRP43, (cp)SRP54 and LHCP, which interacts with (cp)FtsY and Alb3 at the membrane. GTP hydrolysis by (cp)SRP54 and (cp)FtsY triggers complex dissociation.
Victor Zegarra+7 more
wiley +1 more source
Making tau amyloid models in vitro: a crucial and underestimated challenge
This review highlights the challenges of producing in vitro amyloid assemblies of the tau protein. We review how accurately the existing protocols mimic tau deposits found in the brain of patients affected with tauopathies. We discuss the important properties that should be considered when forming amyloids and the benchmarks that should be used to ...
Julien Broc, Clara Piersson, Yann Fichou
wiley +1 more source