Structural, functional, and regulatory evaluation of a cysteine post-translationally modified Gcn5-related N-acetyltransferase.

Polyamines within the cell are tightly regulated by spermidine/spermine N-acetyltransferase (SSAT) enzymes. While several SSATs have been investigated in different bacterial species, there is still a significant gap in knowledge about which proteins are functional SSATs in many organisms. For example, while it is known that Pseudomonas aeruginosa synthesizes the polyamine spermidine, the SSAT that acetylates this molecule and its importance in regulating intracellular polyamines remains unknown.

Characterizing the microstructural transition at the gray matter-white matter interface: Implementation and demonstration of age-associated differences.

Background: The cortical gray matter-white matter interface (GWI) is a natural transition zone where the composition of brain tissue abruptly changes and is a location for pathologic change in brain disorders. While diffusion magnetic resonance imaging (dMRI) is a reliable and well-established technique to characterize brain microstructure, the GWI is difficult to assess with dMRI due to partial volume effects and is normally excluded from such studies.

Methods: In this study, we introduce an approach to characterize the dMRI microstructural profile across the GWI and to assess the sharpness of the microstructural transition from cortical gray matter (GM) to white matter (WM).

Fe starvation induces a second LHCI tetramer to photosystem I in green algae.

Iron (Fe) availability limits photosynthesis at a global scale where Fe-rich photosystem (PS) I abundance is drastically reduced in Fe-poor environments. We used single-particle cryo-electron microscopy to reveal a unique Fe starvation-dependent arrangement of light-harvesting chlorophyll (LHC) proteins where Fe starvation-induced TIDI1 is found in an additional tetramer of LHC proteins associated with PSI in and . These cosmopolitan green algae are resilient to poor Fe nutrition.

Aromatic amino acid metabolism and active transport regulation are implicated in microbial persistence in fractured shale reservoirs.

Hydraulic fracturing has unlocked vast amounts of hydrocarbons trapped within unconventional shale formations. This large-scale engineering approach inadvertently introduces microorganisms into the hydrocarbon reservoir, allowing them to inhabit a new physical space and thrive in the unique biogeochemical resources present in the environment. Advancing our fundamental understanding of microbial growth and physiology in this extreme subsurface environment is critical to improving biofouling control efficacy and maximizing opportunities for beneficial natural resource exploitation.

Spinal Anatomy Ultrasound in Young Infants With Implications for Lumbar Puncture.

Background: Lumbar puncture (LP) in young infants may challenge clinicians due to the infrequency of the procedure and anatomic variability. The use of ultrasound (US) to characterize young infant spinal anatomy prior to performing an LP may help determine the most favorable site for intervention.

Objectives: 1) Evaluate potential sites for LP in young infants with US at L2/L3 through L5/S1 to determine differences in needle insertion depth (NID), spinal canal width (SCW), and subarachnoid fluid width (SAW).