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341.
Madiha Zaynab Huirong Chen Yufei Chen Liao Ouyang Xuewei Yang Zhangli Hu Shuangfei Li 《Saudi Journal of Biological Sciences》2021,28(3):1900-1912
Labrenzia sp. are important components of marine ecology which play a key role in biochemical cycling. In this study, we isolated the Labrenzia sp. PO1 strain capable of forming biofilm, from the A. sanguinea culture. Growth analysis revealed that strain reached a logarithmic growth period at 24 hours. The whole genome of 6.21813 Mb of Labrezia sp. PO1 was sequenced and assembled into 15 scaffolds and 16 contigs, each with minimum and maximum lengths of 644 and 1,744,114 Mb. A total of 3,566 genes were classified into five pathways and 31 pathway groups. Of them, 521 genes encoded biofilm formation proteins, quorum sensing (QS) proteins, and ABC transporters. Gene Ontology annotation identified 49,272 genes that were involved in biological processes (33,425 genes), cellular components (7,031genes), and molecular function (7,816 genes). We recognised genes involved in bacterial quorum sensing, attachment, motility, and chemotaxis to investigate bacteria's ability to interact with the diatom phycosphere. As revealed by KEGG pathway analysis, several genes encoding ABC transporters exhibited a significant role during the growth and development of Labrenzia sp. PO1, indicating that ABC transporters may be involved in signalling pathways that enhance growth and biofilm formation. 相似文献
342.
Dinesh Kumar Ah-Reum Lee Sandeep Kaur Dong-Kwon Lim 《Journal of visualized experiments : JoVE》2015,(103)
Present work demonstrates the simple, chemical free, fast, and energy efficient method to produce reduced graphene oxide (r-GO) solution at RT using visible light irradiation with plasmonic nanoparticles. The plasmonic nanoparticle is used to improve the reduction efficiency of GO. It only takes 30 min at RT by illuminating the solutions with Xe-lamp, the r-GO solutions can be obtained by completely removing gold nanoparticles through simple centrifugation step. The spherical gold nanoparticles (AuNPs) as compared to the other nanostructures is the most suitable plasmonic nanostructure for r-GO preparation. The reduced graphene oxide prepared using visible light and AuNPs was equally qualitative as chemically reduced graphene oxide, which was supported by various analytical techniques such as UV-Vis spectroscopy, Raman spectroscopy, powder XRD and XPS. The reduced graphene oxide prepared with visible light shows excellent quenching properties over the fluorescent molecules modified on ssDNA and excellent fluorescence recovery for target DNA detection. The r-GO prepared by recycled AuNPs is found to be of same quality with that of chemically reduced r-GO. The use of visible light with plasmonic nanoparticle demonstrates the good alternative method for r-GO synthesis. 相似文献
343.
Hannes Link Bernd Anselment Dirk Weuster-Botz 《Metabolomics : Official journal of the Metabolomic Society》2008,4(3):240-247
Effective and rapid inactivation of cellular metabolism is a prerequisite for accurate metabolome analysis. Cold methanol
quenching is commonly applied to stop any metabolic activity and, at the same time remaining the cells’ integrity. However,
it is reported that especially prokaryotic cells like Escherichia coli and Corynebacterium glutamicum tend to leak intracellular metabolites during cold methanol quenching. In this work leakage of adenylates is quantified for
different quenching fluids. Further, a methanol/glycerol based quenching fluid is proposed, which reduces leakage drastically
compared to the commonly applied methanol/water solution (16% ATP leakage compared to more than 70%). 相似文献
344.
N.-U. Frigaard Shinichi Takaichi Masamitsu Hirota Keizo Shimada Katsumi Matsuura 《Archives of microbiology》1997,167(6):343-349
The light-harvesting chlorosome antennae of anaerobic, photosynthetic green sulfur bacteria exhibit a highly redox-dependent
fluorescence such that the fluorescence intensity decreases under oxidizing conditions. We found that chlorosomes from Chlorobium tepidum contain three isoprenoid quinone species (chlorobiumquinone, menaquinone-7, and an unidentified quinone that probably is
a chlorobiumquinone derivative) at a total concentration of approximately 0.1 mol per mol bacteriochlorophyll c. Most of the cellular chlorobiumquinone was found in the chlorosomes and constituted about 70% of the total chlorosome quinone
pool. When the quinones were added to artificial, chlorosome-like bacteriochlorophyll c aggregates in an aqueous solution, a high redox dependency of the fluorescence was observed. Chlorobiumquinones were most
effective in this respect. A lesser redox dependency of the fluorescence was still observed in the absence of quinones, probably
due to another unidentified redox-active component. These results suggest that quinones play a significant, but not exclusive
role in controlling the fluorescence and in inhibiting energy transfer in chlorosomes under oxic conditions. Chlorosomes from
Chloroflexus aurantiacus contained menaquinone in an amount similar to that of total quinone in Chlorobium tepdium chlorosomes, but did not contain chlorobiumquinones. This may explain the much lower redox-dependent fluorescence observed
in Chloroflexus chlorosomes.
Received: 4 November 1996 / Accepted: 18 February 1997 相似文献