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61.
Background
Identifying essential genes in bacteria supports to identify potential drug targets and an understanding of minimal requirements for a synthetic cell. However, experimentally assaying the essentiality of their coding genes is resource intensive and not feasible for all bacterial organisms, in particular if they are infective. 相似文献62.
Background
Phylogenies capture the evolutionary ancestry linking extant species. Correlations and similarities among a set of species are mediated by and need to be understood in terms of the phylogenic tree. In a similar way it has been argued that biological networks also induce correlations among sets of interacting genes or their protein products. 相似文献63.
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66.
Surface Plasmodium sugar-binding components evidenced by fluorescent neoglycoproteins 总被引:2,自引:0,他引:2
J Schrevel M Philippe F Bernard M Monsigny 《Biology of the cell / under the auspices of the European Cell Biology Organization》1986,56(1):49-55
A sugar-binding component was shown to be present at the surface of endoerythrocytic Plasmodium berghei and P. chabaudi stages and merozoites by means of a panel of neoglycoproteins using fluorescence microscopy and flow cytofluorometry. The protein nature of this material was ascertained by the loss of sugar-binding capacity upon trypsin treatment. This lectin-like protein primarily bound neoglycoprotein-borne N-acetylglucosamine and secondarily bound neoglycoprotein-borne alpha-D-glucose, beta-D-galactose and alpha-L-fucose. These results suggest the presence of at least one type of lectin-like protein with an extended binding site accomodating several sugar units, and define its localization on the parasite surface. 相似文献
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69.
Dongliang Liu Jun Liu Weilan Wang Lijie Xia Jianhua Yang Surong Sun Fuchun Zhang 《Food biophysics》2016,11(4):319-331
Cecropin XJ, as a heat stable antimicrobial peptide (AMP), displayed broad bacteriostatic activities, effectively inhibited proliferation of cancer cells and induced cell apoptosis in vitro. However, it exhibited little hemolytic activity and very low cytotoxicity to erythrocytes and normal cells. Although exerts multiple remarkable bioactivities, the refined molecular conformation of native Cecropin XJ remains unsolved. The aim of the present study is to comprehensively investigate the physicochemical characteristics and structure-function relationship of this antimicrobial peptide by using a series of bioinformatics and experimental approaches. In this study, we revealed that the mature Cecropin XJ consists of 41 amino acids, containing two α-helical structures from Lys7 to Lys25 and from Ala29 to Ile39. The phylogenetic tree indicated that Cecropin XJ belongs to the Class I AMPs of cecropin family. Hydrophobic analysis showed Cecropin XJ is a typical amphiphilic molecule. The surface of Cecropin XJ was found to have a much wide range of electrostatic potential from ?83.243 to +83.243. The amphipathicity and surface potential of Cecropin XJ partially supported the AMP pore-forming hypothesis. Scanning electron microscopy experimentally confirmed the damages of Cecropin XJ to microbial membrane. Four predicted docking sites respectively for magnesium ion (Mg2+), adenosine diphosphate (ADP), bacteriopheophytin (BPH), and guanosine triphosphate (GTP) were found on the surface of Cecropin XJ. Thereinto, Mg2+ was experimentally proved to suppress the antibacterial activity of Cecropin XJ; both GTP and ADP enhanced the bactericidal activities to varying degrees. The present study provides a foundation for further investigation of molecular evolution, structural modification, and functional mechanisms of Cecropin XJ. 相似文献
70.
Roberta L. Millstein 《Journal of the history of biology》2008,41(2):339-367
Biologists and philosophers have been extremely pessimistic about the possibility of demonstrating random drift in nature,
particularly when it comes to distinguishing random drift from natural selection. However, examination of a historical case
– Maxime Lamotte’s study of natural populations of the land snail, Cepaea nemoralis in the 1950s – shows that while some pessimism is warranted, it has been overstated. Indeed, by describing a unique signature
for drift and showing that this signature obtained in the populations under study, Lamotte was able to make a good case for
a significant role for␣drift. It may be difficult to disentangle the causes of drift and selection acting in a population,
but it is not (always) impossible. 相似文献