Publications by authors named "David Woolford"
The essential double-ring eukaryotic chaperonin TRiC/CCT (TCP1-ring complex or chaperonin containing TCP1) assists the folding of approximately 5-10% of the cellular proteome. Many TRiC substrates cannot be folded by other chaperonins from prokaryotes or archaea. These unique folding properties are likely linked to TRiC's unique heterooligomeric subunit organization, whereby each ring consists of eight different paralogous subunits in an arrangement that remains uncertain.
View Article and Find Full Text PDFPhenoloxidases (POs) occur in all organisms and are involved in skin and hair coloring in mammals, and initiating melanization in wound healing. Mutation or overexpression of PO can cause albinism or melanoma, respectively. SDS can convert inactive PO and the oxygen carrier hemocyanin (Hc) into enzymatically active PO.
View Article and Find Full Text PDFThe automation of single particle selection and tomographic segmentation of asymmetric particles and objects is facilitated by continuing improvement of methods based on the detection of pixel discontinuity. Here, we present the new arbitrary z-crossings approach which can be employed to enhance the accuracy of edge detection algorithms that are based on the second derivative. This is demonstrated using the Laplacian of Gaussian (LoG) filter.
View Article and Find Full Text PDFArticle Synopsis
- Advances in 3D electron microscopy are enhancing our ability to visualize subcellular structures and proteins, but damage from electron beams limits image quality.
- A new discriminative bilateral (DBL) filter improves noise reduction in these images by distinguishing between important object edges and unwanted high-frequency noise.
- The DBL filter proves effective for enhancing low signal-to-noise ratio data, making it beneficial for both single particle analysis and preparing cellular tomograms for better segmentation.
Article Synopsis
- Single particle analysis (SPA) with high-resolution electron cryo-microscopy is a vital technique for determining the structures of membrane proteins and macromolecular assemblies, needing around 10,000 to 100,000 particle projections for a 3A resolution 3D reconstruction.
- Swarm(PS) is a user-friendly software designed to streamline the particle picking process for these projects, utilizing advanced algorithms like cross-correlation and edge detection while allowing for interactive user input to optimize performance.
- The software supports handling multiple images, offers various particle selection methods, and ensures flexibility for corrections, ultimately facilitating the exporting of data for further image processing.