The Impact of Sugar Conformation on the Single-Stranded DNA Selectivity of APOBEC3A and APOBEC3B Enzymes.

The APOBEC3 family of polynucleotide cytidine deaminases has diverse roles as viral restriction factors and oncogenic mutators. These enzymes convert cytidine to uridine in single-stranded (ss)DNA, inducing genomic mutations that promote drug resistance and tumor heterogeneity. Of the seven human APOBEC3 members, APOBEC3A (A3A) and APOBEC3B (A3B) are most implicated in driving pro-tumorigenic mutations.

Revealing the Impacts of Chemical Complexity on Submicrometer Sea Spray Aerosol Morphology.

Sea spray aerosol (SSA) ejected through bursting bubbles at the ocean surface is a complex mixture of salts and organic species. Submicrometer SSA particles have long atmospheric lifetimes and play a critical role in the climate system. Composition impacts their ability to form marine clouds, yet their cloud-forming potential is difficult to study due to their small size.

Isotopic Insights into Organic Composition Differences between Supermicron and Submicron Sea Spray Aerosol.

To elucidate the seawater biological and physicochemical factors driving differences in organic composition between supermicron and submicron sea spray aerosol (SSA and SSA), carbon isotopic composition (δC) measurements were performed on size-segregated, nascent SSA collected during a phytoplankton bloom mesocosm experiment. The δC measurements indicate that SSA contains a mixture of particulate and dissolved organic material in the bulk seawater. After phytoplankton growth, a greater amount of freshly produced carbon was observed in SSA with the proportional contribution being modulated by bacterial activity, emphasizing the importance of the microbial loop in controlling the organic composition of SSA.