Mutational analysis of an archaeal minichromosome maintenance protein exterior hairpin reveals critical residues for helicase activity and DNA binding

<p>Abstract</p> <p>Background</p> <p>The mini-chromosome maintenance protein (MCM) complex is an essential replicative helicase for DNA replication in Archaea and Eukaryotes. While the eukaryotic complex consists of six homologous proteins (MCM2-7), the archaeon <it>Sulfolobus solfataricus </it>has only one MCM protein (ssoMCM), six subunits of which form a homohexamer. We have recently reported a 4.35Å crystal structure of the near full-length ssoMCM. The structure reveals a total of four β-hairpins per subunit, three of which are located within the main channel or side channels of the ssoMCM hexamer model generated based on the symmetry of the N-terminal <it>Methanothermobacter thermautotrophicus </it>(mtMCM) structure. The fourth β-hairpin, however, is located on the exterior of the hexamer, near the exit of the putative side channels and next to the ATP binding pocket.</p> <p>Results</p> <p>In order to better understand this hairpin's role in DNA binding and helicase activity, we performed a detailed mutational and biochemical analysis of nine residues on this exterior β-hairpin (EXT-hp). We examined the activities of the mutants related to their helicase function, including hexamerization, ATPase, DNA binding and helicase activities. The assays showed that some of the residues on this EXT-hp play a role for DNA binding as well as for helicase activity.</p> <p>Conclusions</p> <p>These results implicate several current theories regarding helicase activity by this critical hexameric enzyme. As the data suggest that EXT-hp is involved in DNA binding, the results reported here imply that the EXT-hp located near the exterior exit of the side channels may play a role in contacting DNA substrate in a manner that affects DNA unwinding.</p

A new stilbene from Agonis flexuosa leaves and verification of its histamine release inhibitory activity using in silico and in vitro studies

This study aimed to explore the phytoconstituents of Agonis flexuosa, F. Myrtaceae and its biological activity. A thorough phytochemical investigation of its leaves led to the isolation of one new stilbene glycoside; (Z)-2,3-dihydroxystilbene-5-O-β-D-glucoside (1), and fifteen known compounds identified as two stilbenes: (Z)-pinosylvin mono methyl ether (2) and (Z)-pinosylvin-3-O-β-D-glucoside (3); six flavanones: (2S)-pinostrobin (4), (2S)-strobopinin (5), (2S)-cryptostobin (6), (2S)-pinocembrin (7), (2S)-dimethylpinocembrin (8) and (2S)-dimethylstrobopinin (9); four flavonoids: quercetin (10), kaempferol-7-O-β-D-glucoside (11), quercetin-3-O-α-D-rhamnoside (12) and quercetin-3-O-β-D-glucoside (13), α-terpineol (14), β-sitosterol (15) and gallic acid (16). The structures of the isolated metabolites were elucidated based upon the interpretation of their 1D and 2D NMR (One Dimensional and Two-Dimensional Nuclear Magnetic Resonance), HR-ESI-MS (High Resolution Electrospray Ionization Mass Spectrometry) and optical rotation. All the isolated compounds were evaluated for their antimicrobial activities. Only compound (6) showed a selective activity against P. aeruginosa with IC50 value of 4.88 µM. In silico virtual screening was done for the isolated compounds on Human histamine H1 receptor (3RZE) downloaded from protein data bank. All the compounds showed certain degree of binding to the protein displaying free binding energies ranging between -11 to -31 kcal/mol. (Z)-2,3-Dihydroxystilbene-5-O-β-D-glucoside (1) showed notable fitting to the active site as evidenced by its free binding energy (∆G) which is computed as -25.09 kcal/mol comparable to diclofenac that displayed (∆G) of -15.00 kcal/mol. In vitro assessment of histamine release inhibitory activity was performed using U937 human monocytes. Compound (1) showed a substantial inhibition to histamine release displaying IC50 value of 0.16 μM

Performance of crossbred dairy Friesian calves fed two levels of Saccharomyces cerevisiae: Intake, digestion, ruminal fermentation, blood parameters and faecal pathogenic bacteria

11 páginas, 6 tablas.The effect of feeding two levels of Saccharomyces cerevisiae on the performance of crossbred Friesian calves was investigated. Twenty-four neonatal male Friesian × Baladi calves (35·5 ± 0·25 kg of initial body weight) were randomly assigned in a completely randomized design into three experimental groups for 90 days (eight calves per group). Calves fed their diets without yeast (S. cerevisiae) were considered as Control, while the diets of other calves were supplemented daily either with 2·5 g (YL diet) or with 5 g (YH diet) of yeast per calf. Calves fed the YH diet showed increased feed intake, while dry matter and fibre digestibilities were increased in calves fed YH and YL diets. Calves fed YL and YH diets showed lower ruminal ammonia-N and higher total volatile fatty acids, acetate and propionate concentrations than Control calves. Both YH and YL calves showed increased plasma concentrations of total protein, globulin and glucose and decreased cholesterol and triglycerides concentrations. Calves' final weight and daily gain were increased with S. cerevisiae yeast supplemented diets. After 42 days of experiment, Clostridium spp., Escherichia coli and Enterobacteria spp. counts were down to undetectable levels in the faeces of calves fed S. cerevisiae additive. It could be concluded that adding S. cerevisiae to milk-fed calves increased feed utilization and improved pre-weaned calf performance and health status, reducing faecal pathogenic bacteria. Copyright © Cambridge University Press 2016.Peer reviewe

Nutrition Anemia and Physical Endurance Among Civil Construction Workers

Penyelidikan ini adalah untuk membuktikan suatu hypothesa bahwa ada pengaruh dari keadaan gizi dan kesehatan terhadap kemampuan bekerja para pekerja. Sejumlah 571 pekerja laki-laki telah dipilih dari tiga daerah tempat bekerja yaitu : Rentang, Seladarma (pembuatan canalj Halim Perdanakusuma (pembuatan lapangan terbang) Didapatkan bahwa seluruh pekerja mempunyai nilai gizi yang borderline dan tidak ada perbedaan didalam keadaan fisik mereka, namun masih terdapat rata-rata 30 percent menderita anemia. Anemia banyak disertai dengan rendahnya kadar Iron darah pada pekerja di Rentang dan Seladarma hal ini tidak terdapat pada pekerja di Halim. (Table 4). Mengenai infeksi cacing terutama cacing tambang maka diseluruh pekerja menderita infeksi cacing tersebut tingkat pertama yaitu infeksi ringan yang tidak akan mempengaruhi keadaan fisik kecuali hanya kekurangan Iron didalam darah. Untuk mengetahui kemampuan bekerja maka telah dipakai Harvard Step Test Scores selama 5 menit. Dan ternyata bila pekerja-pekerja tersebut dibagi dua group yaitu yang diatas dan yang dibawah nilai Hb. 11 Gm/100 ml maka terdapat perbedaan yang menyolok sekali atas kemampuan pekerja tersebut didalam melakukan test fisik. Hal ini sesuai dengan penyelidikan Veteri. Perlu juga disini diketahui bahwa pekerja berasal dari Rentang dan Seladarma lebih banyak menggunakan tenaga kaki oleh karena selalu naik dan turun canal. Kesimpulan penyelidikan ini adalah adanya pengaruh yang positip antara faktor makanan dan infeksi cacing dengan kemampuan bekerja yang dewasa ini amat diperlukan didalam pembangunan negara

Design, Synthesis and Biological Evaluation of Novel Pyrimido[4,5-d]pyrimidine CDK2 Inhibitors as Anti-Tumor Agents

A series of 2,5,7-trisubstituted pyrimido[4,5-d]pyrimidine cyclin-dependent kinase (CDK2) inhibitors is designed and synthesized. 6-Amino-2-thiouracil is reacted with an aldehyde and thiourea to prepare the pyrimido[4,5-d]-pyrimidines. Alkylation and amination of the latter ones give different amino derivatives. These compounds show potent and selective CDK inhibitory activities and inhibit in vitro cellular proliferation in cultured human tumor cells

Local randomness in Hardy's correlations: Implications from information causality principle

Study of nonlocal correlations in term of Hardy's argument has been quite popular in quantum mechanics. Recently Hardy's argument of non-locality has been studied in the context of generalized non-signaling theory as well as theory respecting information causality. Information causality condition significantly reduces the success probability for Hardy's argument when compared to the result based on non-signaling condition. Here motivated by the fact that maximally entangled state in quantum mechanics does not exhibit Hardy's non-local correlation, we do a qualitative study of the property of local randomness of measured observable on each side reproducing Hardy's non-locality correlation,in the context of information causality condition. On applying the necessary condition for respecting the principle of information causality, we find that there are severe restrictions on the local randomness of measured observable in contrast to results obtained from no-signaling condition.Still, there are some restrictions imposed by quantum mechanics that are not obtained from information causality condition.Comment: 6 pages, 2 tables, new references adde

Biologically guided isolation and ADMET profile of new factor Xa inhibitors fromGlycyrrhiza glabraroots usingin vitroandin silicoapproaches

Selective factor Xa inhibitors effectively block coagulation cascade with a broader therapeutic window than multitargeted anticoagulants. They have evolved as a crucial part of prevention and treatment of thromboembolic diseases and in therapeutic protocols involved in many clinical trials in coronavirus disease 2019 (COVID-19) patients. Biologically-guided isolation of specific FXa inhibitors from licorice (Glycyrrhiza glabra) root extract furnished ten flavonoids. By detailed analysis of their1H,13C NMR and MS data, the structures of these flavonoids were established as 7,4′-dihydroxyflavone (1), formononetin (2), 3-R-glabridin (3), isoliquiritigenin (4), liquiritin (5), naringenin 5-O-glucoside (6), 3,3′,4,4′-tetrahydroxy-2-methoxychalcone (7), liquiritinapioside (8) and the two isomers isoliquiritigenin-4′-O-β-d-apiosylglucoside (9) and isoliquiritigenin-4-O-β-d-apiosylglucoside (10). All the isolated compounds were assessed for their FXa inhibitory activity usingin vitrochromogenic assay for the first time. Liquirtin (5) showed the most potent inhibitory effects with an IC50of 5.15 μM. The QikProp module was implemented to perform ADMET predictions for the screened compounds

Home Automation Using Arduino and ESP8266

With the advent of technology, life has become faster in pace and shorter in interactions, with others, as well as with the surroundings. In such a scenario, there is a need to have an endeavor to have everything at the push of a button away, and more importantly, automated. Home Automation is such an endeavor, in which, all the electrical appliances present at home are connected to each other, having interactions with sensors placed at strategic positions in a closed loop manner in order to perform meager tasks automatically, leaving less burden on the humans. With this project we are promoting the fact that Home Automation can greatly contribute to energy conservation too