ジャーナル: Acta Crystallogr F Struct Biol Commun / 年: 2025 タイトル: Cryo-EM structures of Mycobacterium tuberculosis imidazole glycerol phosphate dehydratase in the apo state and in the presence of small molecules. 著者: Rahul Raina / Deepsikha Kar / Mohini Singla / Satish Tiwari / Swati Kumari / Sonanjali Aneja / Varun Kumar / Soumya Banerjee / Shivika Goyal / Ravi Kant Pal / Kutti R Vinothkumar / Bichitra Biswal / 要旨: Unlike humans, Mycobacterium tuberculosis (Mtb), the causative agent of human tuberculosis, has a de novo histidine-biosynthesis pathway. The enzyme imidazole glycerol phosphate dehydratase (IGPD), ...Unlike humans, Mycobacterium tuberculosis (Mtb), the causative agent of human tuberculosis, has a de novo histidine-biosynthesis pathway. The enzyme imidazole glycerol phosphate dehydratase (IGPD), which catalyses the conversion of imidazole glycerol phosphate to imidazole acetol phosphate, has been studied extensively from various organisms and has become a major target for the development of antibacterial, antiweed and antifungal small molecules. In our previous studies, we have shown that in crystals IGPD forms a 24-mer oligomeric state in which the monomers are arranged in 432 symmetry. In order to gain insights into the oligomeric state of Mtb IGPD in solution, we determined cryogenic sample electron microscopy (cryo-EM) structures of apo IGPD at 2.2 and 3.1 Å resolution. In addition, we also determined the cryo-EM structure of IGPD in the presence of 3-amino-1,2,4-triazole (ATZ) to 2.8 Å resolution. The results of this work, which corroborate those from the crystallographic studies, indicate that IGPD forms a homo-oligomeric structure in solution comprising of 24 subunits. ATZ binds in the active-site pocket of the enzyme, which is located at the interface of three monomers and tethers 24 ATZ molecules. The results of this study suggest that cryo-EM, in addition to being a rapidly evolving and complementary imaging technology for elucidating 3D structures of biological macromolecules, can be useful in pinpointing the mode of binding small molecules of low mass (here ∼85 Da) and mapping protein-ligand interactions, which could assist in the design of accurate (high-potency) inhibitors.
名称: Mycobacterium tuberculosis HisB,5-bromo-1-propyl-1H-1,2,4-traizole added but not modelled タイプ: complex / ID: 1 / 親要素: 0 / 含まれる分子: #1 / 詳細: An oligomer of 24 subunits
由来(天然)
生物種: Mycobacterium tuberculosis (結核菌)
分子量
理論値: 550 KDa
-
分子 #1: Imidazoleglycerol-phosphate dehydratase
分子
名称: Imidazoleglycerol-phosphate dehydratase / タイプ: protein_or_peptide / ID: 1 詳細: The enzyme was expressed with a Histag at the N-terminus but not observed in the experiment. The C-terminal residues are also not observed in the experiment. The original uniprot ID doesn't ...詳細: The enzyme was expressed with a Histag at the N-terminus but not observed in the experiment. The C-terminal residues are also not observed in the experiment. The original uniprot ID doesn't exist (I6XBW5) but uniparc ID is UPI000012C861. コピー数: 24 / 光学異性体: LEVO / EC番号: imidazoleglycerol-phosphate dehydratase