Cysteine-Selective Phosphonamidate Electrophiles for Modular Protein Bioconjugations.

We describe a new technique in protein synthesis that extends the existing repertoire of methods for protein modification: A chemoselective reaction that induces reactivity for a subsequent bioconjugation. An azide-modified building block reacts first with an ethynylphosphonite through a Staudinger-phosphonite reaction (SPhR) to give an ethynylphosphonamidate. The resulting electron-deficient triple bond subsequently undergoes a cysteine-selective reaction with proteins or antibodies. We demonstrate that ethynylphosphonamidates display excellent cysteine-selective reactivity combined with superior stability of the thiol adducts, when compared to classical maleimide linkages. This turns our technique into a versatile and powerful tool for the facile construction of stable functional protein conjugates.

Spatial monitoring technologies for coupling the soil plant water animal nexus.

Systems-level studies aimed at determining how soil properties are linked to plant production and ultimately animal response spatially are lacking. This study aims to identify if grazing pressure is linked to soil properties, terrain attributes, and above-ground plant accumulation and nutritive value in a silvopastoral (or integrated tree-livestock) system. Overall, cattle prefer grazing native grasses (2.81 vs. 1.24 h ha-1 AU-1) and udic (dry) landscape positions compared to aquic (wet) areas (2.07 vs. 1.60 h ha-1 AU-1). Greater grazing frequency occurs in udic soils with greater phosphorus and potassium contents and with accumulated forage with less lignin (P ≤ 0.05), which correspond to reduced elevation and greater tree height and diameter (shade) during summer mob grazing. Combining spatial monitoring technologies (both soil and animal) with forage allowance can optimize grazing systems management and sustainability spatially and temporally.