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271.
Maharjan Rukesh Khan Arif Iftikhar Nadeem-ul-Haque Muhammad Maresca Marc Choudhary M. Iqbal Shaheen Farzana Simjee Shabana U. 《Probiotics and antimicrobial proteins》2022,14(2):391-405
Probiotics and Antimicrobial Proteins - Anti-microbial peptides (AMPs) have attracted major attention due to their potential bio-activities against some multidrug resistant pathogens. The present... 相似文献
272.
Nisar M Ahmad M Wadood N Lodhi MA Shaheen F Choudhary MI 《Journal of enzyme inhibition and medicinal chemistry》2009,24(1):47-51
Two new diterpenoid alkaloids, heterophyllinine-A (1) and heterophyllinine-B (2), along with two known alkaloids dihydroatisine (3) and lycoctonine (4) were isolated from the roots of Aconitum heterophyllum Wall. The structure of (1) and (2), were deduced on the basis of spectral data. Compounds 1-2 inhibited acetylcholinesterase (AChE, EC 3.1.1.7) and butyrylcholinesterase (BChE, EC 3.1.1.8) enzymes in a concentration-dependent manner with percent inhibition ranging between 4.24% and 6.94 % and 79.1 % and 82.75 % for AChE and BChE, respectively indicating that compounds 1 and 2 are about thirteen times more specific to BChE than AChE. 相似文献
273.
Tsung-Po Lai Karen A. Stauffer Athulaprabha Murthi Hussam H. Shaheen Gang Peng Nancy C. Martin Anita K. Hopper 《Traffic (Copenhagen, Denmark)》2009,10(9):1243-1256
Trm1 is a tRNA specific m2 2 G methyltransferase shared by nuclei and mitochondria in Saccharomyces cerevisiae . In nuclei, Trm1 is peripherally associated with the inner nuclear membrane (INM). We investigated the mechanism delivering/tethering Trm1 to the INM. Analyses of mutations of the Ran pathway and nuclear pore components showed that Trm1 accesses the nucleoplasm via the classical nuclear import pathway. We identified a Trm1 cis-acting sequence sufficient to target passenger proteins to the INM. Detailed mutagenesis of this region uncovered specific amino acids necessary for authentic Trm1 to locate at the INM. The INM information is contained within a sequence of less than 20 amino acids, defining the first motif for addressing a peripheral protein to this important subnuclear location. The combined studies provide a multi-step process to direct Trm1 to the INM: (i) translation in the cytoplasm; (ii) Ran-dependent import into the nucleoplasm; and (iii) redistribution from the nucleoplasm to the INM via the INM motif. Furthermore, we demonstrate that the Trm1 mitochondrial targeting and nuclear localization signals are in competition with each other, as Trm1 becomes mitochondrial if prevented from entering the nucleus. 相似文献
274.
Li J Sharma R Patrick B Sharma A Jeyabal PV Reddy PM Saini MK Dwivedi S Dhanani S Ansari NH Zimniak P Awasthi S Awasthi YC 《Biochemistry》2006,45(40):12253-12264
The Fas (apo/CD95) receptor which belongs to the TNF-alpha family is a transmembrane protein involved in the signaling for apoptosis through the extrinsic pathway. During this study, we have examined a correlation between intracellular levels of 4-HNE and expression of Fas in human lens epithelial (HLE B-3) cells. Our results show that in HLE B-3 cells, Fas is induced by 4-HNE in a concentration- and time-dependent manner, and it is accompanied by the activation of JNK, caspase 3, and the onset of apoptosis. Fas induction and activation of JNK are also observed in various tissues of mGsta4 null mice which have elevated levels of 4-HNE. Conversely, when 4-HNE is depleted in HLE B-3 cells by a transient transfection with hGSTA4, Fas expression is suppressed. However, upon the cessation of hGSTA4 expression in these transiently transfected cells, Fas and 4-HNE return to their basal levels. Fas-deficient transformed HLE B-3 cells stably transfected with hGSTA4 show remarkable resistance to apoptosis. Also, the wild-type HLE B-3 cells in which Fas is partially depleted by siRNA acquire resistance to 4-HNE-induced apoptosis, suggesting an at least partial role of Fas in 4-HNE-induced apoptosis in HLE B-3 cells. We also demonstrate that during 4-HNE-induced apoptosis of HLE B-3 cells, Daxx is induced and it binds to Fas. Together, these results show an important role of 4-HNE in regulation of the expression and functions of Fas. 相似文献
275.
276.
Mushtaq Hussain Rafiq M. Khanani Nusrat Jabeen Shaheen S. Shoaib Talat Mirza 《Biologia》2010,65(2):183-190
The virulence and transmissibility of viruses are highly associated with their binding specificity to the host cell receptor. In influenza, this initial event of viral pathogenesis is mediated by a glycoprotein known as hemagglutinin (HA). In the present study we constructed homology models of the chain A of hemagglutinin (HA1) of 2009 swine influenza strain. The modeled proteins were compared with atomic coordinates of 1918 (Spanish flu strain) and 1930 HA1 (swine influenza strain). HA1 of recent swine influenza strain showed 84.83% and 93.14% homology with the same versions of 1918 and 1930 strains, respectively. Discrepancies in multiple sequence alignment particularly at the ligand-binding residues notified its receptor specificity to α-2,6 sialic acids in 1918 and 2009 viral strains in contrast to α-2,3 sialic acids as found in 1930 swine flu strain. This implicated the relatively closer relationship of 2009 strain with 1918 strain rather than swine origin strain of 1930. Similarly, the spatial orientations of receptor-binding residues, located in 190-helix, 130-loop and 220-loop, were found more aligned in 1918 and 2009 (RMSD 0.98 Å) than in 1930 and 2009 (RMSD 1.06 Å) strains HA1. More similarities were established between both human origin influenza viruses (1918 and 2009 strains) by the receptor-binding cavity architecture and the orientation of protease cleavage site (Arg327). Briefly, the present finding is expected to show molecular discrepancies and congruencies among the recent and past pandemic influenza strains and may also potentially illustrate the drug targets to rein the infection at earlier stages. 相似文献
277.
In contrast to endophyte-free (E−) tall fescue, endophyte-infected (E+) tall fescue pastures appear to enhance soil carbon sequestration. A hypothetical mechanism that may account for the enhanced carbon sequestration is that the E+ tall fescue affects the soil microbial community or components of it that are involved in organic carbon turnover. A 60-week mesocosm study with a factorial arrangement of soil type, loamy sand (LS) and clay loam (CL), and E+ and E− tall fescue was conducted to determine if the soil microbial communities were affected by the presence of the endophyte. Bulk and rhizosphere soil samples were fixed in paraformaldehyde, and prepared for total direct microbial counts, and with a combination of one of a domain or subdivision fluorescent oligonucleotide probe for enumerating metabolically active Eubacteria, bacterial subdivisions, and Archaea. E+ tall fescue suppressed the archaeal and high G+C gram-positive bacterial communities of the bulk CL, the delta-proteobacterial community in the rhizosphere CL, and the Planctomycetes community of the rhizosphere LS. In the long-term, suppression of these microbial communities may be a factor in enhanced soil carbon sequestration associated with E+ tall fescue. 相似文献
278.
279.
The acromial tracker is used to measure scapular rotations during dynamic movements. The method has low accuracy in high elevations and is sensitive to its attachment location on the acromion. The aim of this study was to investigate the effect of the attachment position and shoulder orientation during calibration on the tracker accuracy. The tracker was attached to one of three positions: near the anterior edge of the acromion process, just above the acromial angle and the meeting point between the acromion and the scapular spine. The scapula locator was used to track the scapula during bilateral abduction simultaneously. The locator was used to calibrate the tracker at: no abduction, 30°, 60°, 90° and 120° humerothoracic abduction. ANOVA tests compared RMS errors for different attachment positions and calibration angles. The results showed that attaching the device at the meeting point between the acromion and the scapular spine gave the smallest errors and it was best to calibrate the device at 60° for elevations ≤90°, at 120° for elevations >90° and at 90°or 120° for the full range of abduction. The accuracy of the tracker is significantly improved if attached appropriately and calibrated for the range of movement being measured. 相似文献
280.
Iqbal Choudhary M Shahab Alam M Atta-Ur-Rahman Yousuf S Wu YC Lin AS Shaheen F 《Steroids》2011,76(14):1554-1559
Pregnenolone (1) was used as a template to develop new anticancer compounds. Ring-D modification of 1 resulted in the synthesis of benzylidenes 2-17, pyrazolines 18-76, pyrazoles 85-91, hydrazones 77-84, and oximes 92-107 derivatives. The structure of compound 107 was also deduced through single crystal X-ray diffraction studies. The inclusion of furanyl and pyridyl rings to pregnenolone skeleton increases the cytotoxicity of all compounds significantly. Among benzylidene derivatives, only heterocyclic enone 8 (IC50 = 0.74 μM/mL against HepG2), and 17 (IC50 = 4.49 μM/mL against HepG2, IC50 = 5.01 μM/mL against MDA-MB-230 cancer cell line) exhibited a significant activity. The cytotoxicity data of pyrazoline derivatives 18-76 revealed that only furanyl bearing pyrazolines 40, 42-44, 48, and 49 exhibited significant activities. While all (O-carboxymethyl) oximes, hydazones, and pyrazoles derivatives of pregnenolone did not show any significant activity against both the cell lines. Thus the furanyl bearing enone 8 (IC50 = 0.74 μM/mL against HepG2), and its pyrazoline derivative 48 (IC50 = 0.91 μM/mL against MDA-MB-230 cancer cell lines) were identified as the most active compounds in all derivatives of pregnenolone. 相似文献