A molecular dynamics study of the binary complexes of APP,JIP1, and the cargo binding domain of KLC

Mutations in the amyloid precursor protein (APP) are responsible for the formation of amyloid‐β peptides. These peptides play a role in Alzheimer's and other dementia‐related diseases. The cargo binding domain of the kinesin‐1 light chain motor protein (KLC1) may be responsible for transporting APP either directly or via interaction with C‐jun N‐terminal kinase‐interacting protein 1 (JIP1). However, to date there has been no direct experimental or computational assessment of such binding at the atomistic level. We used molecular dynamics and free energy estimations to gauge the affinity for the binary complexes of KLC1, APP, and JIP1. We find that all binary complexes (KLC1:APP, KLC1:JIP1, and APP:JIP1) contain conformations with favorable binding free energies. For KLC1:APP the inclusion of approximate entropies reduces the favorability. This is likely due to the flexibility of the 42‐residue APP protein. In all cases we analyze atomistic/residue driving forces for favorable interactions. Proteins 2017; 85:221–234. © 2016 Wiley Periodicals, Inc.     

Carbodiimides inhibit the acid-induced purple-to-blue transition of bacteriorhodopsin

Reaction of purple membrane with water soluble carbodiimides inhibits the spectral transition from purple to blue observed at acid pH. The pK and Hill constant for this transition are shifted from 3.4 to 2.6 and from 1.8 to 0.85, respectively. The results suggest a connection between the uptake side of the proton pump and the purple-to-blue transition.     

Nitrogen Addition in a Tibetan Alpine Meadow Increases Intraspecific Variability in Nitrogen Uptake,Leading to Increased Community-level Nitrogen Uptake

Ecosystems - Plant nitrogen (N) uptake is a critical ecosystem function, especially when terrestrial ecosystems are threatened worldwide by increasing anthropogenic N deposition. However, the...