The Structural Maintenance of Chromosome (SMC) protein is essential for various cellular processes, including chromosome organization, DNA repair, and genome stability. MksB, an alternative SMC protein present in prokaryotes, comprises a hinge dimerization domain and an ABC ATPase head domain linked by a coiled-coil arm. While hinge dimerization in bacterial and eukaryotic SMCs is attributed to conserved glycines, our study unveils the critical role of a novel KDDR motif located at a loop near the hinge dimer interface in Mycobacterium smegmatis MksB (MsMksB).
View Article and Find Full Text PDFRetrosynthetic design and synthesis with structural isolation of two unprecedented core modified N-confused N-fused porphodimethene-like porphyrinoids possessing a [5.5.5.
View Article and Find Full Text PDFLipids are essential biological macromolecules that play a pivotal role in various physiological processes and cellular homeostasis. ABHD16B, a member of the α/β-hydrolase domain (ABHD) superfamily protein, has emerged as a potential key regulator in lipid metabolism. However, the precise role of human ABHD16B in lipid metabolism remains unclear.
View Article and Find Full Text PDFPancreatic lipase (PL) is a keen target for anti-obesity therapy that reduces dietary fat absorption. Here, we investigated the binding patterns of 220 PL inhibitors having experimental IC values, using molecular docking and binding energy calculations. Screening of these compounds illustrated most of them bound at the catalytic site (S1-S2 channel) and a few compounds are at the non-catalytic site (S2-S3 channel/S1-S3 channel) of PL.
View Article and Find Full Text PDFJudicious syntheses, spectroscopic analyses, and solid state structural evidence of two structural variants (with planar geometry) of strongly aromatic hybrid [30] -ethylene bridged hexaphyrins (2.1.1.
View Article and Find Full Text PDFThe human alpha beta hydrolase domain (ABHD) proteins are ubiquitous and regulate the cellular lipids' anabolic and catabolic processes. The structural aspects for specific biochemical function of many ABHD proteins related to physiological disorders and its link to pathological conditions remain unknown. Here putative human ABHD16B protein was overexpressed in Saccharomyces cerevisiae for its biological activity.
View Article and Find Full Text PDFStructural isolation of two unprecedented AIEE/ACQ type fluorophores based on -methyl N-confused tripyrromonomethene analogues exhibiting selective F anion-coordination-induced-enhanced emission (ACIEE) with a detection limit of 10 M is reported. The intrinsic relation between molecular structures/molecular arrangements with (without) anion binding have been revealed at a deeper level spectroscopic measurements and DFT level theoretical studies.
View Article and Find Full Text PDFThe bifunctional flavin adenine dinucleotide synthetase (FADS) synthesizes the flavin mononucleotide (FMN) and flavin adenine dinucleotide (FAD) co-factors essential for the function of flavoproteins. The Staphylococcus aureus FADS (SaFADS) produces FMN from riboflavin (RF) by ATP:riboflavin kinase (RFK) activity at its C-terminal domain. The N-terminal domain converts FMN to FAD under a reducing environment by FMN:ATP adenylyltransferase (FMNAT) activity which is reversible (FAD pyrophosphorylase activity).
View Article and Find Full Text PDFRational design and isolation of two hitherto unknown highly stable single conformer of ferrocene incorporated meso-aryl substituted singly N-methyl N-confused-calixphyrins have been achieved in quantitative yields. The solid-state crystal structure reveals the obvious trans-geometry for the meso-protons with the possibility for both the macrocycles to exist either racemic or enantiomer forms. However, thorough solution-state spectroscopic characterization strongly concludes the experimental isolation of a single isomer for both the macrocycles.
View Article and Find Full Text PDFConcise syntheses and spectroscopic, solid state X-ray crystal structure and theoretical studies of three electronically appealing new generation hitherto unknown ferrocenyl bridged N-confused heterocyclic macrocycles with (without) fusion are reported. Intriguingly, the expanded N-confused fused phlorin (1.1.
View Article and Find Full Text PDFCoronavirus Disease-2019 (COVID-19), a viral disease caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) was declared a global pandemic by WHO in 2020. In this scenario, SARS-CoV-2 main protease (COVID-19 M), an enzyme mainly involved in viral replication and transcription is identified as a crucial target for drug discovery. Traditionally used medicinal plants contain a large amount of bioactives and pave a new path to develop drugs and medications for COVID-19.
View Article and Find Full Text PDFExpedient synthesis, spectroscopic, solid state structural proof, and theoretical study of helically twisted weakly aromatic hybrid singly N-confused ferrocenoporphyrinoids and the peripheral coordinated Rh(I) complex are reported. The X-ray crystal structure of the macrocycles reveals an ambiguously inverted pyrrole ring reinforcing regioselective β,β-linkage with the spatially adjacent N-confused -methyl pyrrole ring leading to endocyclic extension of macrocyclic π-conjugation via tricyclic [5.5.
View Article and Find Full Text PDFFlavin adenine dinucleotide synthetase (FADS), a bifunctional prokaryotic enzyme, is involved in the synthesis of two vital cofactors, flavin mononucleotide (FMN) and flavin adenine dinucleotide (FAD). Here, we investigated the biochemical characteristics of FADS from Staphylococcus aureus (Sa), a pathogenic bacteria causing food-borne diseases. The SaFADS possesses riboflavin kinase (RFK) and FMN adenylyltransferase (FMNAT) activities that transforms riboflavin to FMN and FMN to FAD, respectively.
View Article and Find Full Text PDFHigh yield synthesis and spectroscopic isolation of two hitherto unknown highly stable single conformers of meso-aryl substituted dithia/diselena trans-doubly N-confused porphyrins with fully π-conjugated [18] annulene structures are reported. In-depth solution state spectroscopic measurements and DFT level theoretical calculations strongly show the distinct aromaticity with strong NIR absorption of these new macrocycles.
View Article and Find Full Text PDFHuman sucrase enzyme is a key therapeutic target for type 2 diabetes. While sugarcane sucrase inhibitor (sucinh) modulates invertase activity thereby accumulates sucrose. Molecular level understanding of sucinh towards mammalian α-glucosidases is scarce.
View Article and Find Full Text PDFMetal binding sites are present in one-third of proteins and are crucial for biological functions and structural maintenance. GH26 endo-mannanase (ManB-1601) from Bacillus sp. harbors a Zn binding site which connects N (H1, H23) and C (E336)-terminal residues.
View Article and Find Full Text PDFHigh-yield synthesis, spectroscopic and solid-state structural proof of the lactam-embedded smallest ever metal-free stable Hückel antiaromatic -doubly N-confused [16] porphyrins are reported. These new facets of -doubly N-confused porphyrins have been anticipated to exhibit the redox-associated variation of Hückel aromaticity as a mere consequence of the amido-like structures of the N-confused N-methyl pyrrole rings of the macrocycles. Strong aromaticity upon NaBH reduction leading to a resonance dipolar structure of the [18]π-conjugated system as the reduced congener with concomitant Hückel topology are the important highlights.
View Article and Find Full Text PDFA concise and convenient synthetic methodology leading to an unambiguous isolation of two hitherto unknown highly stable single conformers of meso-aryl substituted unorthodox 5,10-porphodimethenes has been developed by the inclusion of N-methyl pyrrole units with α,β and β,β-linkages into the core of heterocyclic macrocycles.
View Article and Find Full Text PDFHitherto, how salt bridges contribute towards the structure-function of endo-mannanases has not been demonstrated. In the present study, we revealed that ManB-1601 (GH26 endo-mannanase from Bacillus sp.) has eight salt bridges which are highly conserved among GH26 endo-mannanases from Bacillus spp.
View Article and Find Full Text PDFTwo hitherto unknown conformationally rigid Hückel aromatic ethynylene-cumulene conjugated [30] heteroannulenes have been synthesized and characterized. A thorough solution-state spectroscopic characterization, combined with in-depth theoretical calculations, has been performed to arrive at the proposed geometry of the macrocycles. The most stable optimized structures for the free base form of both the macrocycles showed absolute planar geometries without any ring inversion with mean plane deviation (MPD) values of 0.
View Article and Find Full Text PDFBiochem Biophys Res Commun
December 2018
Brown adipose tissue (BAT) is the site of non-shivering thermogenesis in mammals, wherein energy is dissipated as heat. We observed that aqueous extract of black sesame seed triggers an increase in the expression of Uncoupling Protein 1 (UCP1) in brown adipocytes from mice. The active component from the extract was purified and identified to be sesaminol diglucoside (SDG).
View Article and Find Full Text PDFAcne is a multifactorial skin disease, underpinned by colonization of Propionibacterium acnes and inflammation. The emergence of resistant P. acnes strains has affected the current acne treatment algorithm.
View Article and Find Full Text PDFThe C-H bond activation of methane mediated by a prototypical heteronuclear metal-oxide cluster, [Al2Mg2O5](•+), was investigated by using Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS) in conjunction with high-level quantum mechanical calculations. Experimentally, hydrogen-atom abstraction from methane by the cluster ion [Al2Mg2O5](•+) takes place at ambient conditions. As to the mechanism, according to our computational findings, both the proton-coupled electron transfer (PCET) and the conventional hydrogen-atom transfer (HAT) are feasible and compete with each other.
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