Leucine Aminopeptidase LyLAP enables lysosomal degradation of membrane proteins.

Unlabelled: Proteolysis of hydrophobic helices is required for complete breakdown of every transmembrane protein trafficked to the lysosome and sustains high rates of endocytosis. However, the lysosomal mechanisms for degrading hydrophobic domains remain unknown. Combining lysosomal proteomics with functional genomic data mining, we identify Lysosomal Leucine Aminopeptidase (LyLAP; formerly Phospholipase B Domain-Containing 1) as the hydrolase most tightly associated with elevated endocytic activity.

Proteases influence colony aggregation behavior in Vibrio cholerae.

Aggregation behavior provides bacteria protection from harsh environments and threats to survival. Two uncharacterized proteases, LapX and Lap, are important for Vibrio cholerae liquid-based aggregation. Here, we determined that LapX is a serine protease with a preference for cleavage after glutamate and glutamine residues in the P1 position, which processes a physiologically based peptide substrate with a catalytic efficiency of 180 ± 80 Ms.

A Prototype Assay Multiplexing SARS-CoV-2 3CL-Protease and Angiotensin-Converting Enzyme 2 for Saliva-Based Diagnostics in COVID-19.

With the current state of COVID-19 changing from a pandemic to being more endemic, the priorities of diagnostics will likely vary from rapid detection to stratification for the treatment of the most vulnerable patients. Such patient stratification can be facilitated using multiple markers, including SARS-CoV-2-specific viral enzymes, like the 3CL protease, and viral-life-cycle-associated host proteins, such as ACE2. To enable future explorations, we have developed a fluorescent and Raman spectroscopic SARS-CoV-2 3CL protease assay that can be run sequentially with a fluorescent ACE2 activity measurement within the same sample.

Large library docking for novel SARS-CoV-2 main protease non-covalent and covalent inhibitors.

Antiviral therapeutics to treat SARS-CoV-2 are needed to diminish the morbidity of the ongoing COVID-19 pandemic. A well-precedented drug target is the main viral protease (M ), which is targeted by an approved drug and by several investigational drugs. Emerging viral resistance has made new inhibitor chemotypes more pressing.

Characterization of a unique polysaccharide monooxygenase from the plant pathogen .

Blast disease in cereal plants is caused by the fungus and accounts for a significant loss in food crops. At the outset of infection, expression of a putative polysaccharide monooxygenase (PMO9A) is increased. PMO9A contains a catalytic domain predicted to act on cellulose and a carbohydrate-binding domain that binds chitin.

A moonlighting function of a chitin polysaccharide monooxygenase, CWR-1, in allorecognition.

Organisms require the ability to differentiate themselves from organisms of different or even the same species. Allorecognition processes in filamentous fungi are essential to ensure identity of an interconnected syncytial colony to protect it from exploitation and disease. has three cell fusion checkpoints controlling formation of an interconnected mycelial network.

A dual-fluorophore sensor approach for ratiometric fluorescence imaging of potassium in living cells.

Potassium is the most abundant intracellular metal in the body, playing vital roles in regulating intracellular fluid volume, nutrient transport, and cell-to-cell communication through nerve and muscle contraction. On the other hand, aberrant alterations in K homeostasis contribute to a diverse array of diseases spanning cardiovascular and neurological disorders to diabetes to kidney disease to cancer. There is an unmet need for studies of K physiology and pathology owing to the large differences in intracellular extracellular K concentrations ([K] = 150 mM, [K] = 3-5 mM).

Substrate selectivity in starch polysaccharide monooxygenases.

Degradation of polysaccharides is central to numerous biological and industrial processes. Starch-active polysaccharide monooxygenases (AA13 PMOs) oxidatively degrade starch and can potentially be used with industrial amylases to convert starch into a fermentable carbohydrate. The oxidative activities of the starch-active PMOs from the fungi and , AA13 and AA13, respectively, on three different starch substrates are reported here.

A Modular Ionophore Platform for Liver-Directed Copper Supplementation in Cells and Animals.

Copper deficiency is implicated in a variety of genetic, neurological, cardiovascular, and metabolic diseases. Current approaches for addressing copper deficiency rely on generic copper supplementation, which can potentially lead to detrimental off-target metal accumulation in unwanted tissues and subsequently trigger oxidative stress and damage cascades. Here we present a new modular platform for delivering metal ions in a tissue-specific manner and demonstrate liver-targeted copper supplementation as a proof of concept of this strategy.