1. ABOUT THE DATASET -------------------- Title: Data associated with 'Guanine Crystallization at Physiological pH' Creator(s): Bidisha Tah Roy,[a] Lukas Jorin Hasselt,[a] Zijiang Yang,[a] Ross Young,[a] Jeanine Williams,[a] Johanna M. Galloway,[a] Alex Heyam, [a] Yi-Yeoun Kim [a] and Fiona C. Meldrum [a] Organisation(s): [a] School of Chemistry, Woodhouse Lane, University of Leeds, Leeds, LS2 9JT, United Kingdom Rights-holder(s):Unless otherwise stated, Copyright 2025 University of Leeds Publication Year: 2025 Description: Molecular organic crystals such as guanine are widely used by organisms for their remarkable optical properties. However, little is currently known about the mechanisms by which organisms control their formation, where efforts to elucidate these have been impeded by the very low solubility of these molecules in aqueous solutions at neutral pH. This creates significant challenges in crystallizing them under biologically-relevant conditions in the laboratory. Here, we introduce an enzymatic approach based on the purine metabolism process that yields significant quantities of guanine crystals in aqueous solution at neutral pH. The enzyme purine nucleoside phosphorylase (PNP) is used to continuously convert guanosine to guanine and generate supersaturation, and pure beta anhydrous guanine (-AG) or alpha anhydrous guanine (-AG) can be produced by changing the reagent concentrations or introducing stirring. Investigation of the reaction kinetics using high performance liquid chromatography (HPLC) and NMR reveals that the rate of change of supersaturation is crucial in determining the polymorph. This work bridges the gap between in vitro and biological crystallization and provides a facile means of studying the crystallization of biological molecules. Cite as: Bidisha Tah Roy, Lukas Jorin Hasselt, Zijiang Yang, Ross Young,Jeanine Williams, Johanna M. Galloway, Alex Heyam, Yi-Yeoun Kim, and Fiona C. Meldrum (2024): Data associated with 'Guanine Crystallization at Physiological pH'. University of Leeds. [1552] [https://doi.org/10.5518/1552], 2. TERMS OF USE --------------- [A standard copyright notice and licence statement with URL can be used, e.g. Copyright [2024] [University of Leeds]. Unless otherwise stated, this dataset is licensed under a Creative Commons Attribution 4.0 International Licence: https://creativecommons.org/licenses/by/4.0/.] 3. PROJECT AND FUNDING INFORMATION ---------------------------------- Title: DYNAMIN , Crystallization in the Real World Dates: [1/3/2018-29/2/2024] Funding organisation: European Research Council, EPSRC Grant no.:788968, EP/R018820/1, EP/T006331/1 4. CONTENTS ----------- File listing HPLC data contain the raw data. The polts are done by using Origin 2019 software. The origin file names are mathched with the image number nu,mbe mentioned in the original manuscript/Supproting information. NMR raw data was processed by using Bruker Topspin software. The polts are done by using Origin 2019 software. The origin file names are mathched with the image number, mentioned in the original manuscript/Supproting information. XRD raw data was processed by using using DiffractEVA software. The polts are done by using Origin 2019 software. The origin file names are mathched with the image number, mentioned in the original manuscript/Supproting information. Raman data was processed by LabSpec6 software. The exported text files were plotted by using Origin2019 software. The origin file names are mathched with the image number, mentioned in the original manuscript/Supproting information. SEM Images are placed in the folder named 'SEM'. The file names are mathched with the image number, mentioned in the original manuscript/Supproting information. STEM data was processed by Expert PI software. For analysis Imagej and digital micrograph was used. To simulate the diffraction pattern we have used the crystal diffract siftware. The .tiff-file names are mathched with the image number, mentioned in the original manuscript/Supproting information. 5. METHODS ---------- Detailed information about methods is available in the supporting Information section with fully referenced. - To plot the graphs for Raman, XRD, NMR, and HPLC data, we used Origin 2019 software. You can find the user guide for Origin functions at the following link: [OriginLab Documentation](https://www.originlab.com/doc/Origin-Help). Before using the software, you need to install Origin 2019 on your PC. - Additional Software and Data: XRD Data Processing: The `XRD.brml` data was processed using DiffractEVA software. SEM Images: The `collected_SEM.tif` files contain scanning electron micrographs of crystals collected from filtered crystals on silicon wafers or Millipore filter paper. TEM Images: The `TEM.tif` files contain transmission electron micrographs. For indexing these images, we used ImageJ software and Digital Micrograph.