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1.
Kevin M. Smith Fahimeh Eivazi Kevin C. LangryJose A. P. Baptista de Almeida George W. Kenner 《Bioorganic chemistry》1979,8(4):485-495
An efficient total synthesis of 1,5-di(trideuteromethyl)protoporphyrin-IX (3) dimethyl ester from monopyrrole precursors is described, the synthesis proceeding through crystalline tripyrrene and a,c-biladiene salt intermediates. The 2- and 4-vinyl groups in (3) are formed from the corresponding (2-chloroethyl) substituents by way of base-promoted dehydrochlorination. In protio solvents, this synthetic step is shown to exchange out preferentially deuterons in the 1-methyl group, and this observation is exploited in an efficient synthesis of the 1,3-di(trideuteromethyl)protoporphyrin-IX (22) dimethyl ester from 2,4-diacetyldeuteroporphyrin-IX (20) dimethyl ester (which is in turn accessible from commercially available protoporphyrin-IX (5)). Thus, basic exchange in deuterated solvent of (20) gives the deuterated analog, which after reduction and dehydration gives the 1,3-di(trideuteromethyl)protoporphyrin-IX analog (22), in which the vinyl H2 and propionic CH2·CO functions have also become deuterated. 相似文献
2.
In an attempt to increase tolerance to salinity stress in tobacco plants, the genes encoding the mutant form of glutamyl kinase
(proB), pyrroline-5-carboxylate synthetase, and osmotin were cloned into three different shuttle vectors and were separately introduced
into the tobacco plants. The transgenic lines were compared for their ability to produce shoots and grow in MS medium containing
320 mM NaCl; it was shown that the transgenic lines containing genetically handled osmotin gene are more resistant to salinity. The amount of chlorophyll a was used to show continuing growth of plant lines. The results showed that only the tobacco lines transformed with the modified
osmotin gene exhibited greater tolerance to salinity.
Published in Russian in Fiziologiya Rastenii, 2006, Vol. 53, No. 1, pp. 122–127.
The text was submitted by the authors in English. 相似文献
3.
Saeid Kalantari-Dehaghi Bahman Ebrahimi-Hosseinzadeh Zahra-Beagom Mokhtari-Hosseini Fahimeh Nojoki Javad Hamedi 《Preparative biochemistry & biotechnology》2013,43(3):286-297
AbstractCo-v-culture (co-cultivations of physically separated microbes that only interact through the air) systems were designed to investigate the effects of microbial volatile organic compounds (mVOCs) from about 20 different microbes, on a medicinal fungus, Ganoderma lucidum. For more accuracy in co-cultivations, a novel synchronized cultivation approach was tested for culturing G. lucidum. The hyphal growth of G. lucidum and the content of its ganoderic acids (GAs) were measured. In almost all of the co-v-cultures, there was an inhibiting effect on hyphal growth and a promoting effect on GAs contents. In inducing GAs production, Bacillus cereus PTCC 1247 and Pseudomonas aeruginosa UTMC 1404 were the most effective ones, as, compared to control cultures, GAs content increased 2.8 fold. Comparing different co-v-cultivations demonstrated that the concentrations of mVOCs, oxygen, and carbon dioxide were the main players in co-v-cultures. No correlation was found between hyphal growth and GAs production. Strains of the same species imposed totally different effects on hyphal growth or GAs production. This study has investigated the effects of mVOCs on G. lucidum for the first time. Moreover, it suggests that co-v-cultivation may be a promising biotechnological approach to improve the production in G. lucidum. 相似文献
4.
Seyed Nezamedin Hosseini Amin Javidanbardan Behnaz Sadat Alizadeh Salim 《Preparative biochemistry & biotechnology》2013,43(8):683-692
AbstractThe costly media, inconsistent ligand density, ligand leakage, and possible destabilization of recombinant hepatitis B surface antigen (rHBsAg) particles are main drawbacks of using immunoaffinity chromatography (IAF) in the large-scale downstream processing. In this study, we aimed to use an efficient large-scale purification system as an alternative purification method for immunoaffinity chromatography. For this purpose, we suggested integrating non-affinity chromatographic methods of hydrophobic interaction chromatography (HIC) and size-exclusion chromatography (SEC) for cost-effective purification of rHBsAg expressed in P. pastoris. The optimization of such process is not trivial and straightforward since diverse molecular characteristics of expressed rHBsAg in each type of host cell cause different interactions in non-affinity chromatography processes. The working buffer composition and chromatography parameters are the most influential factors in hydrophobic interaction chromatography. The best result for lab-scale HIC was achieved by using ammonium sulfate buffer in 10% of saturation concentration in pH 7.0 with Butyl-S Sepharose 6 Fast Flow medium and with subsequent Tween-100 and urea elution. In this process, the recovery, purity, and total yield were about 84%, 82%, and 69%, respectively. By scaling-up the HIC and integrating it with Sephacryl S-400?SEC, we obtained highly pure, i.e.,?>?90%, rHBsAg virus-like particles (VLP). 相似文献
5.
Habibzadeh Seyyedeh Zahra Salehzadeh Ali Moradi-Shoeili Zeinab Shandiz Seyed Ataollah Sadat 《Molecular biology reports》2020,47(3):1637-1647
Molecular Biology Reports - Gastric cancer is one of the common types of cancer around the world which has few therapeutic options. Nitrogen heterocyclic derivatives such as thiazoles are used as... 相似文献
6.
Fahimeh Khorsand Maedeh Darziani Azizi Ali Naeemy Bagher Larijani Kobra Omidfar 《Molecular biology reports》2013,40(3):2327-2334
3-Hydroxybutyrate, one of the main blood ketone bodies, has been considered as a critical indicator for diagnosis of diabetic ketoacidosis. Biosensors designed for detection of 3-hydroxybutyrate with advantages of precision, easiness and speedy performance have attracted increasing attention. This study attempted to develop a 3-hydroxybutyrate dehydrogenase-based biosensor in which single-walled carbon nanotubes (SWCNT) was used in order to immobilize the cofactor, NAD+, on the surface of screen-printed electrode. The formation of NAD+–SWCNT conjugates was assessed by electrochemistry and electron microscopy. Cyclic voltammetry was used to analyze the performance of this biosensor electrochemically. The considerable shelf life and reliability of the proposed biosensor to analyze real sample was confirmed by this method. The reduction in the over potential of electrochemical oxidation of NADH to ?0.15 V can be mentioned as a prominent feature of this biosensor. This biosensor can detect 3-hydroxybutyrate in the linear range of 0.01–0.1 mM with the low detection limit of 0.009 mM. Simultaneous application of screen-printed electrode and SWCNT has made the biosensor distinguished which can open new prospects for detection of other clinically significant metabolites. 相似文献
7.
Kobra Omidfar Fatemeh Sadat Amjad Zanjani Arghavan Golbaz Hagh Maedeh Darziani Azizi Seyed Javad Rasouli Susan Kashanian 《Molecular biology reports》2013,40(12):6737-6745
Epidermal growth factor receptor (EGFR) is deemed to be one of the main molecular targets for diagnosis and treatment of cancer. It has been identified that EGFR involves in pathogenesis of some forms of human cancers. Monoclonal antibodies targeting EGFR could control the tumor cell growth, proliferation, and apoptosis by suppressing the signal transduction pathways. Nanobodies can be regarded as the smallest intact antigen binding fragments, derived from heavy chain-only antibodies existing in camelids. Here, we describe the identification of an EGFR-specific nanobody, referred to as OA-cb6, obtained from immunized camel with a cell line expressing high levels of EGFR. Utilizing flow cytometry (FACS) and blotting methods, we demonstrated that OA-cb6 nanobody binds specifically to EGFR expressing on the surface of A431 cells. In addition, OA-cb6 nanobody potently causes the inhibition of EGFR over expression, cell growth and proliferation. The antibody fragments can probably be regarded as worthwhile binding block for further rational design of anti-cancer therapy. 相似文献
8.
Zhongzhao Teng Umar Sadat Wenkai Wang Nasim S. Bahaei Shengyong Chen Victoria E. Young Martin J. Graves Jonathan H. Gillard 《PloS one》2013,8(4)
Background
Stretch is a mechanical parameter, which has been proposed previously to affect the biological activities in different tissues. This study explored its utility in determining plaque vulnerability.Methods
One hundred and six patients with mild to moderate carotid stenosis were recruited in this study (53 symptomatic and 53 asymptomatic). High resolution, multi-sequence magnetic resonance (MR) imaging was performed to delineate various plaque components. Finite element method was used to predict high stretch concentration within the plaque.Results
During a two-year follow-up, 11 patients in symptomatic group and 3 in asymptomatic group experienced recurrent cerebrovascular events. Plaque stretch at systole and stretch variation during one cardiac cycle was greater in symptomatic group than those in the asymptomatic. Within the symptomatic group, a similar trend was observed in patients with recurrent events compared to those without.Conclusion
Plaques with high stretch concentration and large stretch variation are associated with increased risk of future cerebrovascular events. 相似文献9.
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