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Controlled reduction of oxygen is important for developing clean energy technologies, such as fuel cells, and is vital to the existence of aerobic organisms. The process starts with oxygen in a triplet ground state and ends with products that are all in singlet states. Hence, spin constraints in the oxygen reduction must be considered. Here, we show that the electron transfer efficiency from chiral electrodes to oxygen (oxygen reduction reaction) is enhanced over that from achiral electrodes. We demonstrate lower overpotentials and higher current densities for chiral catalysts versus achiral ones. This finding holds even for electrodes composed of heavy metals with large spin–orbit coupling. The effect results from the spin selectivity conferred on the electron current by the chiral assemblies, the chiral-induced spin selectivity effect. 

SAMHD1 possesses multiple functions, but whether cellular factors regulateSAMHD1 expression or its function remains not well characterized. Here, by investigating why culturedRDandHEK293T cells show different sensitivity to enterovirus 71 (EV71) infection, we demonstrate thatSAMHD1 is a restriction factor for EV71. Importantly, we identifyTRIM21, an E3 ubiquitin ligase, as a key regulator ofSAMHD1, which specifically interacts and degradesSAMHD1 through the proteasomal pathway. However,TRIM21 has no effect on EV71 replication itself. Moreover, we prove that interferon production stimulated by EV71 infection induces increasedTRIM21 andSAMHD1 expression, whereas increasingTRIM21 overridesSAMHD1 inhibition of EV71 in cells and in a neonatal mouse model.TRIM21‐mediated degradation ofSAMHD1 also affectsSAMHD1‐dependent restriction ofHIV‐1 and the regulation of interferon production. We further identify the functional domains inTRIM21 required forSAMHD1 binding and the ubiquitination site K622 inSAMHD1 and show that phosphorylation ofSAMHD1 at T592 also blocks EV71 restriction. Our findings illuminate how EV71 overcomesSAMHD1 inhibition via the upregulation ofTRIM21.