@article {9056,
	title = {Cryo-EM structures of Mycobacterium tuberculosis imidazole glycerol phosphate dehydratase in the apo state and in the presence of small molecules [National Cryo-EM Facility, BLiSC]},
	journal = {Acta Crystallogr F Struct Biol Commun},
	year = {2025},
	month = {2025 Jul 01},
	abstract = {<p>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 {\r A} 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 {\r A} 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.</p>
},
	issn = {2053-230X},
	doi = {10.1107/S2053230X25004595},
	author = {Raina, Rahul and Kar, Deepsikha and Singla, Mohini and Tiwari, Satish and Kumari, Swati and Aneja, Sonanjali and Kumar, Varun and Banerjee, Soumya and Goyal, Shivika and Pal, Ravi Kant and Vinothkumar, Kutti R and Biswal, Bichitra}
}
@article {8841,
	title = {Exploring advances in single particle CryoEM with apoferritin: From blobs to true atomic resolution [Electron Microscopy (Micro-CT) Facility (INT)]},
	journal = {Int J Biochem Cell Biol},
	volume = {169},
	year = {2024},
	month = {2024 Apr},
	pages = {106536},
	abstract = {<p>Deciphering the three-dimensional structures of macromolecules is of paramount importance for gaining insights into their functions and roles in human health and disease. Single particle cryoEM has emerged as a powerful technique that enables direct visualization of macromolecules and their complexes, and through subsequent averaging, achieve near atomic-level resolution. A major breakthrough was recently achieved with the determination of the apoferritin structure at true atomic resolution. In this review, we discuss the latest technological innovations across the entire single-particle workflow, which have been instrumental in driving the resolution revolution and in transforming cryoEM as a mainstream technique in structural biology. We illustrate these advancements using apoferritin as an example that has served as an excellent benchmark sample for assessing emerging technologies. We further explore whether the existing technology can routinely generate atomic structures of dynamic macromolecules that more accurately represent real-world samples, the limitations in the workflow, and the current approaches employed to overcome them.</p>
},
	keywords = {Apoferritins, Cryoelectron microscopy, Humans, Macromolecular Substances},
	issn = {1878-5875},
	doi = {10.1016/j.biocel.2024.106536},
	author = {Premageetha, Gowtham ThambraRajan and Vinothkumar, Kutti R and Bose, Sucharita}
}
