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981.
Maturation of the bacteriophage HK97 capsid requires a large conformational change of the virus capsid. Experimental studies have identified several intermediates along this maturation pathway. To gain insights into the molecular mechanisms of capsid maturation, we examined the fluctuation dynamics of the procapsid and mature capsid using a residue-level computational approach. The most cooperative motions of the procapsid are found to be consistent with the observed change in configuration that takes place during maturation. A few dominant modes of motion are sufficient to describe the anisotropic expansion that accompanies maturation. Based upon these modes, maturation is proposed to occur via an overall expansion and reconfiguration of the capsid initiated by puckering of the pentamers, followed by flattening and crosslinking of the hexameric subunits, and finally crosslinking of the pentameric subunits. The highly mobile E loops are stabilized by anchoring to highly stable residues belonging to neighboring subunits. 相似文献
982.
Md. Faisal Kabir Abraham Okki Mwamula Jae-Kook Lee Mungi Jeong DongWoon Lee Jung Joon Park 《Journal of Asia》2018,21(2):688-694
Although Heterodera trifolii is commonly known as the clover cyst nematode, recently the nematode has been identified as a serious menace for Chinese cabbage growers in highland areas in Korea. Soil samples were collected from two Chinese cabbage fields highly infested with H. trifolii in highland areas of Korea, Jungsun and Samcheok, in 2014 and 2015, respectively. A total of 777 (2?×?2?m sampling area) and 414 (5?×?5?m area) soil samples were collected from Jungsun and Samcheok, respectively. The total cysts, cysts with eggs, number of eggs, and empty cysts were calculated for each sample. Distribution patterns for these variables were characterized using spatial analysis by distance indices (SADIE) and variogram model analysis. The aggregation index for cysts with eggs was higher in Jungsun (89.32) than Samcheok (3.63), which indicated that the cyst population density was higher. However, the spatial association of total cysts versus cysts with eggs was higher in Samcheok. The Gaussian model showed reasonable independent range of the nematode in Jungsun and Samcheok to be approximately 53.66?m and 48.54?m, respectively. The model suggested that each nematode sample should be taken at least 50?m apart in the given areas. Inclusion of this distribution pattern may significantly minimize the number of samples in future sampling methods, which could save time and labor, and initiate management practices by elucidating spatial variability factors that influence crop yield. 相似文献
983.
984.
Hiroko Yamaya‐Ito Yoshikazu Shimoda Tsuneo Hakoyama Shusei Sato Takakazu Kaneko Md Shakhawat Hossain Satoshi Shibata Masayoshi Kawaguchi Makoto Hayashi Hiroshi Kouchi Yosuke Umehara 《The Plant journal : for cell and molecular biology》2018,93(1):5-16
The nitrogen‐fixing symbiosis of legumes and Rhizobium bacteria is established by complex interactions between the two symbiotic partners. Legume Fix– mutants form apparently normal nodules with endosymbiotic rhizobia but fail to induce rhizobial nitrogen fixation. These mutants are useful for identifying the legume genes involved in the interactions essential for symbiotic nitrogen fixation. We describe here a Fix– mutant of Lotus japonicus, apn1, which showed a very specific symbiotic phenotype. It formed ineffective nodules when inoculated with the Mesorhizobium loti strain TONO. In these nodules, infected cells disintegrated and successively became necrotic, indicating premature senescence typical of Fix– mutants. However, it formed effective nodules when inoculated with the M. loti strain MAFF303099. Among nine different M. loti strains tested, four formed ineffective nodules and five formed effective nodules on apn1 roots. The identified causal gene, ASPARTIC PEPTIDASE NODULE‐INDUCED 1 (LjAPN1), encodes a nepenthesin‐type aspartic peptidase. The well characterized Arabidopsis aspartic peptidase CDR1 could complement the strain‐specific Fix– phenotype of apn1. LjAPN1 is a typical late nodulin; its gene expression was exclusively induced during nodule development. LjAPN1 was most abundantly expressed in the infected cells in the nodules. Our findings indicate that LjAPN1 is required for the development and persistence of functional (nitrogen‐fixing) symbiosis in a rhizobial strain‐dependent manner, and thus determines compatibility between M. loti and L. japonicus at the level of nitrogen fixation. 相似文献
985.
Asif Iqbal Al Hakim Md. Saddam Hossain Mohammad Rejaur Rahman Kamrul Islam Md. Faisal Azim Jahed Ahmed Md. Assaduzzaman Md. Mozammel Hoq Abul Kalam Azad 《Journal of Genetic Engineering and Biotechnology》2018,16(1):29-37
Proteolytic bacteria isolated from municipal solid wastes (MSW) were identified as Serratia marcescens A3 and Pseudomonas putida A2 based on 16S rDNA sequencing. Protease produced through fermentation of organic MSW by these bacteria under some optimized physicochemical parameters was partially purified and characterized. The estimated molecular mass of the partially purified protease from S. marcescens and P. putida was approximately 25 and 38 kDa, respectively. Protease from both sources showed low Km 0.3 and 0.5 mg ml?1 and high Vmax 333 and 500 µmole min?1 at 40?°C, and thermodynamics analysis suggested formation of ordered enzyme-substrate (E-S) complexes. The activation energy (Ea) and temperature quotient (Q10) of protease from S. marcescens and P. putida were 16.2 and 19.9 kJ/mol, and 1.4 and 1.3 at temperature range from 20 to 40 °C, respectively. Protease of the both bacterial isolates was serine and cysteine type. The protease retained approximately 97% of activity in the presence of sodium dodecyl sulphate. It was observed that the purified protease of S. marcescens could remove blood stains from white cotton cloth and degrade chicken flesh remarkably. Our study revealed that organic MSW can be used as raw materials for bacterial protease production and the protease produced by S. marcescens A3 might be potential for applications. 相似文献
986.
Md. Ekramul Karim Kartik Dhar Md. Towhid Hossain 《Journal of Genetic Engineering and Biotechnology》2018,16(2):375-380
Dyeing effluents have become a vital source of water pollution. Due to the xenobiotic properties and toxicity to all life forms including humans, removal of undesirable color and associated toxicity is crucial. In this study, five dye decolorizing bacteria were isolated from dyeing effluent using selective enrichment culture in Bushnell-Haas (BH) medium amended with co-substrate (i.e. glucose, yeast extract) and 100?mg?L?1 of each commercially available reactive dyes viz. Novacron Orange FN-R, Novacron Brilliant Blue FN-R, Novacron Super Black G, Bezema Yellow S8-G and Bezema Red S2-B. The isolated bacteria were identified and assigned as Neisseria sp., Vibrio sp., Bacillus sp., Bacillus sp. and Aeromonas sp. based on their phenotypic (cultural, morphological, physiological and biochemical characteristic) observation. The dye decolorization efficiency was estimated spectrophotometrically up to 6?days of static incubation at 37?°C and observed that all of the isolates were unable to induce decolorization in absence of co-substrate. In case of monoculture, decolorization percentage varies from no visible decolorization (Bezema Red S2-B by Ek-5) to highest 90% decolorization (Novacron Brilliant Blue FN-R by Ek-13) whereas the decolorization percentage of bacterial consortium varies from 65% (Bezema Yellow S8-G) to 90% (Novacron Brilliant Blue FN-R and Novacron Super Black G). The study outlines the co-substrates mediated decolorization process where bacterial consortium proved as efficient dye decolorizer than that of the monocultures. This finding confers possibility of using novel microbial consortium for biological treatment of disreputable dyeing effluents. 相似文献
987.
988.
Summary An alkali treated A. niger biomass was found to efficiently sequester silver ions from dilute as well as concentrated solutions (2.5–1000 ppm Ag+), with an ability to bind it to a level of upto 10% of dry weight. Biosorption of silver ions was not influenced by pH between 5–7. The bound Ag+ could be fully desorbed by dilute HNO3 and the biosorbent regenerated by washing with Ca2+/Mg2+ solution. This biosorbent is unique in that the mechanism of metal ion sorption has been found to be exclusively by stoichiometric exchange with Ca2+ and Mg2+ of the biosorbent. 相似文献
989.
990.
Md. Qumruzzaman Chowdhury Peter Kitin Maaike De Ridder Claire Delvaux Hans Beeckman 《Trees - Structure and Function》2016,30(1):227-239