Macromolecular crystallization: basics and advanced methodologies
JOURNAL OF THE IRANIAN CHEMICAL SOCIETY
Authors: Cheraghian Radi, Hamid; Hajipour-Verdom, Behnam; Molaabasi, Fatemeh
Abstract
For the first time, about 155 years ago and as a laboratory curiosity, German biologists observed the crystals of hemoglobin from worms and fishes. Since then, the crystallization of proteins, nucleic acids and big biological structures, like viruses, has been developed into a broad research field including several applications, for example in the drug discovery. This review is divided into four major sections. The first section addresses the specific physicochemical properties of biomolecular crystals accompanied by kinetics of supersaturation, nucleation and growth which are the three main steps required to achieve macromolecular crystals. Besides, various physical, chemical and biochemical parameters influencing the process of macromolecular crystallization are reviewed. The second part deals with classical approaches, such as vapor and batch diffusion methods, available to create macromolecular crystals. The third part overviews novel approaches including microgravity, cocrystallization, membrane-assisted crystallization and microfluidic array chips involved in more complicated techniques for growing macromolecular crystals and controlling their size and orientation. In the end, considering the very significant role of automation in providing biomolecules' crystals in recent years, we provided a brief explanation about robotics and their importance in developing high-throughput crystallization. RDC-NMR and SAXS/WAXS hybrid methods with the aim of obtaining structural information of complex macromolecular assemblies are also discussed.
Design, synthesis, antimicrobial evaluation and in silico studies of symmetrical bis (urea-1,2,3-triazole) hybrids
RESEARCH ON CHEMICAL INTERMEDIATES
Authors: Poonia, Nisha; Lal, Kashmiri; Kumar, Ashwani
Abstract
In search of 1,2,3-triazole-based antimicrobials, some symmetrical bis(urea-1,2,3-triazole) hybrids were synthesized via clicked Huisgen cycloaddition. The structural characterization was done by different physical and spectral techniques like NMR, FTIR and HRMS. In vitro antimicrobial evaluation of all the synthesized compounds was performed against three bacterial strains (Staphylococcus epidermidis, Escherichia coli and Bacillus subtilis) and two fungal strains (Aspergillus niger and Candida albicans). All the synthesized urea-linked bis(1,2,3-triazole) hybrids (4a-4o) were found to exhibit higher potency than their alkyne precursors (3a-3c). Also, all the synthesized hybrids elicited better antifungal activity than the reference drug Fluconazole against both the fungal strains. Compound 4e and 4o were found to be more potent toward C. albicans with lowest MIC values 0.0112 mu mol/mL and 0.0105 mu mol/mL, respectively. The docking studies of compounds 4e and 4o and their respective alkynes 3b and 3c were carried out in the active site of sterol 14-alpha-demethylase of C. albicans. [GRAPHICS] .