ASBMB Award Articles
Outer membrane vesicles as molecular biomarkers for Gram-negative sepsis: Taking advantage of nature’s perfect packages
Sepsis is an often life-threatening response to infection, occurring when host proinflammatory immune responses become abnormally elevated and dysregulated. To diagnose sepsis, the patient must have a confirmed or predicted infection, as well as other symptoms associated with the pathophysiology of sepsis. However, a recent study found that a specific causal organism could not be determined in the majority (70.1%) of sepsis cases, likely due to aggressive antibiotics or localized infections. The timing of a patient’s sepsis diagnosis is often predictive of their clinical outcome, underlining the need for a more definitive molecular diagnostic test.Increasing access for biochemistry research in undergraduate education: The malate dehydrogenase CURE community
Integrating research into the classroom environment is an influential pedagogical tool to support student learning, increase retention of STEM students, and help students identify as scientists. The evolution of course-based undergraduate research experiences (CUREs) has grown from individual faculty incorporating their research in the teaching laboratory into well-supported systems to sustain faculty engagement in CUREs. To support the growth of protein-centric biochemistry-related CUREs, we cultivated a community of enthusiastic faculty to develop and adopt malate dehydrogenase (MDH) as a CURE focal point.Positively charged amino acids at the N terminus of select mitochondrial proteins mediate early recognition by import proteins αβ′-NAC and Sam37
A major challenge in eukaryotic cells is the proper distribution of nuclear-encoded proteins to the correct organelles. For a subset of mitochondrial proteins, a signal sequence at the N terminus (matrix-targeting sequence [MTS]) is recognized by protein complexes to ensure their proper translocation into the organelle. However, the early steps of mitochondrial protein targeting remain undeciphered. The cytosolic chaperone nascent polypeptide–associated complex (NAC), which in yeast is represented as the two different heterodimers αβ-NAC and αβ′-NAC, has been proposed to be involved during the early steps of mitochondrial protein targeting.Allosteric regulation by membranes and hydrophobic subsites in phospholipase A2 enzymes determine their substrate specificity
Lipids play critical roles in several major chronic diseases of our times, including those that involve inflammatory sequelae such as metabolic syndrome including obesity, insulin sensitivity, and cardiovascular diseases. However, defining the substrate specificity of enzymes of lipid metabolism is a challenging task. For example, phospholipase A2 (PLA2) enzymes constitute a superfamily of degradative, biosynthetic, and signaling enzymes that all act stereospecifically to hydrolyze and release the fatty acids of membrane phospholipids.Click chemistry and optogenetic approaches to visualize and manipulate phosphatidic acid signaling
The simple structure of phosphatidic acid (PA) belies its complex biological functions as both a key phospholipid biosynthetic intermediate and a potent signaling molecule. In the latter role, PA controls processes including vesicle trafficking, actin dynamics, cell growth, and migration. However, experimental methods to decode the pleiotropy of PA are sorely lacking. Because PA metabolism and trafficking are rapid, approaches to accurately visualize and manipulate its levels require high spatiotemporal precision.
