8fwa

Phycocyanin structure from a modular droplet injector for serial femtosecond crystallographyPhycocyanin structure from a modular droplet injector for serial femtosecond crystallography

Structural highlights 8fwa is a 2 chain structure with sequence from Thermosynechococcus vestitus BP-1. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance. Method: X-ray diffraction, Resolution 2Å Ligands: , , Resources: FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT Function PHCA_THEVB Light-harvesting photosynthetic bile pigment-protein from the phycobiliprotein complex (phycobilisome, PBS). Phycocyanin is the major phycobiliprotein in the PBS rod. Publication Abstract from PubMed Droplet injection strategies are a promising tool to reduce the large amount of sample consumed in serial femtosecond crystallography (SFX) measurements at X-ray free electron lasers (XFELs) with continuous injection approaches. Here, we demonstrate a new modular microfluidic droplet injector (MDI) design that was successfully applied to deliver microcrystals of the human NAD(P)H:quinone oxidoreductase 1 (NQO1) and phycocyanin. We investigated droplet generation conditions through electrical stimulation for both protein samples and implemented hardware and software components for optimized crystal injection at the Macromolecular Femtosecond Crystallography (MFX) instrument at the Stanford Linac Coherent Light Source (LCLS). Under optimized droplet injection conditions, we demonstrate that up to 4-fold sample consumption savings can be achieved with the droplet injector. In addition, we collected a full data set with droplet injection for NQO1 protein crystals with a resolution up to 2.7 A, leading to the first room-temperature structure of NQO1 at an XFEL. NQO1 is a flavoenzyme associated with cancer, Alzheimer's and Parkinson's disease, making it an attractive target for drug discovery. Our results reveal for the first time that residues Tyr128 and Phe232, which play key roles in the function of the protein, show an unexpected conformational heterogeneity at room temperature within the crystals. These results suggest that different substates exist in the conformational ensemble of NQO1 with functional and mechanistic implications for the enzyme's negative cooperativity through a conformational selection mechanism. Our study thus demonstrates that microfluidic droplet injection constitutes a robust sample-conserving injection method for SFX studies on protein crystals that are difficult to obtain in amounts necessary for continuous injection, including the large sample quantities required for time-resolved mix-and-inject studies. Modular droplet injector for sample conservation providing new structural insight for the conformational heterogeneity in the disease-associated NQO1 enzyme.,Doppler D, Sonker M, Egatz-Gomez A, Grieco A, Zaare S, Jernigan R, Meza-Aguilar JD, Rabbani MT, Manna A, Alvarez RC, Karpos K, Cruz Villarreal J, Nelson G, Yang JH, Carrion J, Morin K, Ketawala GK, Pey AL, Ruiz-Fresneda MA, Pacheco-Garcia JL, Hermoso JA, Nazari R, Sierra R, Hunter MS, Batyuk A, Kupitz CJ, Sublett RE, Lisova S, Mariani V, Boutet S, Fromme R, Grant TD, Botha S, Fromme P, Kirian RA, Martin-Garcia JM, Ros A Lab Chip. 2023 Jun 28;23(13):3016-3033. doi: 10.1039/d3lc00176h. PMID:37294576 From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

spinqualitylabelsall models 8fwa, resolution 2.00Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image