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121.
R Nagaraj 《Journal of Chemical Sciences》1987,98(5-6):479-485
Proteins destined for regions other than the cytoplasm in cells have to cross at least one membrane barrier before reaching
their proper destination. Almost all such proteins are initially biosynthesized as precursors with signal sequences at the
amino terminus. Signal sequences are essential and also sufficient for proteins to be targeted to membranes and also for translocation
across membranes. One striking feature that is clearly evident amongst signal sequences of secretory proteins is a positively
charged amino terminus followed by a region comprising 10–12 very hydrophobic amino acids. The structural and physico-chemical
properties of signal sequences have been analysed. On the basis of the analyses it is proposed that the structural feature
of a positively charged amino terminal region followed by a hydrophobic stretch of amino acids, rather than a conformational
one, is recognised by components of the cells export machinery. It is also postulated that signal sequences insert in the
lipid bilayer of the translocation competent membrane after targeting. The presence of the signal sequence results in the
formation of local ‘defects’ in the bilayer which have a role in translocation of proteins across membranes. 相似文献
122.
A stereOselective conversion of 1,8- and 1,5-diethoxy-9,10-anthraquinone to 1,8- and 1,5-diketo----perhydroanthracenes by successive sodium borohydride, metal-ammonia, and catalytic reductions is described. 相似文献
123.
124.
125.
Kumar Pardeep Nagaraj Chandana Joshi Raman Goud N. Sridhar Kumar Dinesh Korann Vittal Mangalore Sandhya Rao Naren P. 《Journal of Radioanalytical and Nuclear Chemistry》2021,329(2):581-589
Journal of Radioanalytical and Nuclear Chemistry - Fluorine-18 (18F) flumazenil (FMZ) was synthesized and purified using a single solid-phase cartridge and the formulation was tested in animals for... 相似文献
126.
Recently, infectious diseases caused by bacterial pathogens have become a major cause of morbidity and mortality globally due to their resistance to multiple antibiotics. This has triggered initiatives to develop novel, alternative antimicrobial materials, which solve the issue of infection with multidrug-resistant bacteria. Nanotechnology using nanoscale materials, especially multimetallic nanoparticles (NPs), has attracted interest because of the favorable physicochemical properties of these materials, including antibacterial properties and excellent biocompatibility. Multimetallic NPs, particularly those formed by more than two metals, exhibit rich electronic, optical, and magnetic properties. Multimetallic NP properties, including size and shape, zeta potential, and large surface area, facilitate their efficient interaction with bacterial cell membranes, thereby inducing disruption, reactive oxygen species production, protein dysfunction, DNA damage, and killing potentiated by the host’s immune system. In this review, we summarize research progress on the synergistic effect of multimetallic NPs as alternative antimicrobial agents for treating severe bacterial infections. We highlight recent promising innovations of multimetallic NPs that help overcome antimicrobial resistance. These include insights into their properties, mode of action, the development of synthetic methods, and combinatorial therapies using bi- and trimetallic NPs with other existing antimicrobial agents. 相似文献
127.
Ricin and its corresponding polypeptides (A & B chain) were purified from castor seed. The molecular weight of ricin subunits were 29,000 and 28,000 daltons. The amino acids in ricin determined were Asp45 The22 Ser40 Glu53 Cys4 Gly96 His5 Ile21 Leu33 Lys20 Met4 Phe13 Pro37 Tyr11 Ala45 Val23 Arg20 indicating that ricin contains approximately 516 amino acid residues. The amino acids of the two subunits of ricin A and B chains were Asp23 The12 Ser21 Glu29 Cys2 Gly48 His3 Ile12, Leu17 Lys10 Met2 Phe6 Pro17 Tyr7 Ala35 Val13 Arg13 while in B chain the amino acids were Asp22 The10 Ser19 Glu25 Cys2 Gly47 His1 Ile10, Leu15 Lys11 Met1 Phe7 Pro6 Tyr5 Ala32Val11 Arg10. The total helical content of ricin came around 53.6% which is a new observation. 相似文献
128.
In the laboratories of Mother Nature, enzymes, the most efficient and specific catalysts, have been developed. These proteins have been used by mankind since millennia, e.g., for cheese‐making. By now, enzymes have captured a huge market in industry and handicraft, and even more expansions are certain. Applications range from detergents and textiles to food, animal feed and drugs. Stone‐washed jeans, antibiotics, improved wine corks and ice cream – all these products make us live a very enzyme‐filled life! 相似文献
129.
Y. Munikrishana Reddy M. K. Nagaraj M. Siva Pratap Reddy Jung-Hee Lee V. Rajagopal Reddy 《Brazilian Journal of Physics》2013,43(1-2):13-21
The current-voltage (I–V) and capacitance-voltage (C–V) characteristics of Ni/Cu/n-InP Schottky barrier diodes are studied over a wide temperature range, from 210 K to 420 K. The I–V characteristics display anomalous thermal behavior. The apparent barrier height decays, and the ideality factor grows at low temperatures, and the series resistances resulting from Cheung’s and Norde’s procedures are markedly temperature dependent. The nonlinearity of the Richardson plot and the strong temperature dependence of the Schottky-barrier parameters indicate that the interface is spatially inhomogeneous. Plots of the zero-bias barrier height as a function of 1/(2kT) points to a Gaussian distribution of barrier heights with 0.90 eV mean height and 0.014 eV standard deviation. When this distribution is accounted for, a Richardson of 6.5 A/(cm K)2 results, relatively close to the 9.4/(cm K)2 predicted by theory. We conclude that, combined with a Gaussian distribution of barrier heights, the thermionic-emission mechanism explains the temperature-dependent I–V and C–V characteristics of the studied Schottky-barrier diodes. 相似文献
130.
Divya Monga Surbhi Sharma Nagaraj P. Shetti Soumen Basu Kakarla Raghava Reddy Tejraj M. Aminabhavi 《Materials Today Chemistry》2021
Two-dimensional transition metal dichalcogenides (TMDCs) are the layered materials that have gained substantial consideration in a wide range of applications. The TMDCs possess exceptional properties such as high surface-to-volume ratio, excellent charge transfer capacity, mechanical strength, and low bandgap energy. Additionally, TMDCs (MoS2, WS2, etc.) are abundant, have a low synthesis cost, and are visible-light-active. The appealing surface morphologies and properties of TMDCs make them an appropriate choice for diverse applications like photocatalytic degradation of hazardous pollutants, energy conversion reactions (electrocatalytic and photocatalytic H2 production), and energy storage devices (supercapacitors and rechargeable batteries) in addition to bio/chemical sensors. This article addresses the latest trends and advancements in the domain of TMDC-based nanomaterials. The different synthesis routes have been comprehensively reviewed. The challenges faced by TMDCs at a large scale and the future scope have also been discussed. 相似文献