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921.
922.
Amir Mohaghegh Motlagh Ananda Shankar Bhattacharjee Ramesh Goel 《World journal of microbiology & biotechnology》2016,32(4):67
Bacteriophages, as the most dominant and diverse entities in the universe, have the potential to be one of the most promising therapeutic agents. The emergence of multidrug-resistant bacteria and the antibiotic crisis in the last few decades have resulted in a renewed interest in phage therapy. Furthermore, bacteriophages, with the capacity to rapidly infect and overcome bacterial resistance, have demonstrated a sustainable approach against bacterial pathogens-particularly in biofilm. Biofilm, as complex microbial communities located at interphases embedded in a matrix of bacterial extracellular polysaccharide substances (EPS), is involved in health issues such as infections associated with the use of biomaterials and chronic infections by multidrug resistant bacteria, as well as industrial issues such as biofilm formation on stainless steel surfaces in food industry and membrane biofouling in water and wastewater treatment processes. In this paper, the most recent studies on the potential of phage therapy using natural and genetically-modified lytic phages and their associated enzymes in fighting biofilm development in various fields including engineering, industry, and medical applications are reviewed. Phage-mediated prevention approaches as an indirect phage therapy strategy are also explored in this review. In addition, the limitations of these approaches and suggestions to overcome these constraints are discussed to enhance the efficiency of phage therapy process. Finally, future perspectives and directions for further research towards a better understanding of phage therapy to control biofilm are recommended. 相似文献
923.
Eric J. Gilbert Guowei Zhou Michael K.C. Wong Ling Tong Bandarpalle B. Shankar Chunli Huang Joseph Kelly Brian J. Lavey Stuart W. McCombie Lei Chen Razia Rizvi Youhao Dong Youheng Shu Joseph A. Kozlowski Neng-Yang Shih R. William Hipkin Waldemar Gonsiorek Asra Malikzay Charles A. Lunn Len Favreau Daniel J. Lundell 《Bioorganic & medicinal chemistry letters》2010,20(2):608-611
The triaryl bis-sulfone 1 was modified by converting the aryl A-ring to a piperidine ring. The piperidine ring was further elaborated to a spirocyclopropyl piperidine moiety. The effect on CB2 binding potency, rat calcium channel affinity, and CYP 2C9 inhibition is described. 相似文献
924.
925.
Energy and economic efficiencies were evaluated on young (6 year) and old (20 year) jhum fields in Mizoram, north-eastern
India during second year of cropping, and were compared with those in the first year. The effect of auxiliary measures such
as tilling the soil or application of fertilizers (chemical or farm-yard manure or both in combination) was also examined
on energy and economic efficiencies. The results indicated that traditional jhum cultivation is labour intensive and energy
efficient, producing almost 15–20 times of energy invested. Energy and economic efficiencies decline with shortening of jhum
cycle. These efficiencies decline further from first to second year of cropping. Tilling is not useful to improve either energy
or economic efficiency. Fertilizer application, which is though profitable from the point of view of economic efficiency,
is highly energy inefficient. Application of fertilizers during second year cropping can be encouraged. Organic manuring may
be a better option than others to alleviate energy efficiency. However, a combination of organic and inorgamic manuring could
be the best option to enhance economic efficiency. 相似文献
926.
Sjoerd J. Gerbrandy Vepatu Shankar Kirumakki N. Shivaram Hermann Stegemann 《Phytochemistry》1975,14(11):2331-2333
The conversion of a slow moving potato phosphorylase isozyme to a fast one, in sprouting tubers, either on freezing the whole tubers or on storage of their crude extracts, is due to limited proteolysis. High protease inhibitor concentration seems to be the primary factor preventing this conversion in freshly harvested tubers under similar conditions. Though MW determinations on both isozymes show the removal of a peptide during conversion, it is also likely that the enzyme may take up a different conformation due to the removal of this peptide. 相似文献
927.
GTP-binding proteins have been identified on the membranes of highly purified dextran-filled lysosomes (dextranosomes) and Triton-filled lysosomes (tritosomes) obtained from rat liver. Autoradiography of blots of lysosomal membrane proteins incubated with [alpha-32P]GTP revealed the presence of several specific GTP-binding proteins with a relative molecular mass (M(r)) predominantly in the range of 26-30 kDa. These GTP-binding proteins migrated slower in polyacrylamide gels than purified c-Ha-ras protein expressed in E. coli, whose apparent M(r) was 23 kDa in the same blot. The relative contents of GTP-binding proteins in lysosomal membranes were comparable or greater than that of plasma membranes and of microsomes. Chemical extraction showed that lysosomal GTP-binding proteins were more tightly associated with the membranes than with microsomal GTP-binding proteins. The possible involvement of lysosomal GTP-binding proteins in cellular functions including vacuolar (lysosomal) acidification and organellar dynamics are discussed. 相似文献
928.
Cellular organelles facilitate dimerization of a newly identified Arf from Chlamydomonas reinhardtii
Peeyush Ranjan Rudra Shankar Kashyap Manisha Goel Sindhu Kandoth Veetil Suneel Kateriya 《Journal of phycology》2014,50(6):1137-1145
GTPases of the Ras superfamily regulate a wide variety of cellular processes including vesicular transport and various secretory pathways of the cell. ADP – ribosylation factor (ARF) belongs to one of the five major families of the Ras superfamily and serves as an important component of vesicle formation and transport machinery of the cells. The binding of GTP to these Arfs and its subsequent hydrolysis, induces conformational changes in these proteins leading to their enzymatic activities. The dimeric form of Arf is associated with membrane pinch‐off during vesicle formation. In this report, we have identified an arf gene from the unicellular green alga Chlamydomonas reinhardtii, CrArf, and showed that the oligomeric state of the protein in C. renhardtii is modulated by the cellular membrane environment of the organism. Protein cross‐linking experiments showed that the purified recombinant CrArf has the ability to form a dimer. Both the 20‐kDa monomeric and 40‐kDa dimeric forms of CrArf were recognized from Chlamydomonas total cell lysate (CrTLC) and purified recombinant CrArf by the CrArf specific antibody. The membranous environment of the cell appeared to facilitate dimerization of the CrArf, as dimeric form was found exclusively associated with the membrane bound organelles. The subcellular localization studies in Chlamydomonas suggested that CrArf mainly localized in the cytosol and was mislocalized in vesicle transport machinery inhibitor treated cells. This research sheds light on the importance of the cellular membrane environment for regulating the oligomeric state of CrArf protein in this organism and associated functional role. 相似文献
929.
Rimjhim Roy Choudhury Supriyo Basak Aadi Moolam Ramesh Latha Rangan 《Protoplasma》2014,251(3):703-709
Pongamia pinnata L. is a multipurpose versatile legume that is well known as a prospective feedstock biodiesel species. However, to date, there has been little genomic research aimed at the exploitation of the biotechnological potential of this species. Genetic characterization of any plant is a challenging task when there is no information about the genome size and organization of the species. Therefore, the genome size of P. pinnata was estimated by flow cytometry with respect to two standards (Zea mays and Pisum sativum), and compared with that of in vitro-raised plants (nodal segment, in vitro-rooted plantlets and acclimatized in vitro plants) to study the potential effect of somaclonal variation on genome size. This method can be used to support the establishment of true-to-type plants to encourage afforestation programs. Modified propidium iodide/hypotonic citrate buffer was used for isolation of the intact nuclei. The 2C DNA value of this species was estimated to be 2.51?±?0.01 pg. Statistically, there was no significant difference in the DNA content of the in vitro-grown plants and mother plant at α?=?0.05. As a result of the low genome size of P. pinnata, a species that has adapted itself to a wide range of edaphic and ecological condition, we can now proceed for its next generation sequencing and genomic diversity studies. 相似文献
930.