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281.
Structural information for the gelatinases A (MMP-2) and B (MMP-9), two members of the matrix metalloprotease (MMP) family of enzymes, has been elusive. For the first time, computational structures for the catalytic domains of MMP-2 and MMP-9 are reported herein using the program COMPOSER and the reported three-dimensional structures of the fibroblast collagenase (MMP-1), neutrophil collagenase (MMP-8) and stromelysin-1 (MMP-3). The details of the structures of the catalytic domains of gelatinases and interactions with the protein substrate are discussed. The first analysis of the extent of hydrophobicity of surfaces in the active sites of six MMPs (including the two gelatinases reported herein) is presented to provide distinction for substrate specificity among these metalloproteases. The information from the extent of hydrophobicity/hydrophilicity analysis and general topology for these MMPs was utilized in the proposal of a method for categorization of MMPs of known three-dimensional fold. These efforts provide the first information useful to experimentalists working on the biochemical properties of these important members of the MMP family of enzymes, and provide for an opportunity to compare and contrast structures of gelatinases, collagenases and stromelysins. 相似文献
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‘Prevention is better than cure, especially when something has no cure.’ Cancer, in most patients is detected at the stage beyond which it becomes noncurative. Therefore, the early detection of cancer cells can play a crucial role in enhancing the chances of a patient's survival. In this light, we present a nonfluorescent receptor used for the detection of Zn2+ ion in MDA-MB-231 carcinoma cells that exhibits fluorescence turn-on behaviour upon binding with the metal ion. In this work, the synthesis of 11,16-bis(2,6-difluorobenzene)-6,6,21,21-tetramethyl-meta-benziporpho-6,21-dimethene and its Zn2+ chloride complex have been reported. The compounds were fully characterized using UV–visible, nuclear magnetic resonance (NMR), infrared (IR) and mass spectrometry. Furthermore, the X-ray polymorphs of a meta-benziporphodimethene analogue were added. The study of its bioimaging applications in MDA-MB-231 breast cancer cells for the detection of Zn2+ ions is reported. 相似文献
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A Z Pliusnin O V Nolandt E V Kuznetsova E A Briantseva E A Fridman 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》1988,(8):19-23
DNA probes containing the nucleotide sequences of the conservative genes of influenza A virus (matrix, nucleoprotein and acidic polymerase genes) show their specificity with respect to the RNA of influenza A viruses in mammal tissue cell cultures (continuous spaniel kidney cell culture and primary calf kidney cell culture). The minimal amount of infected monolayer cells, permitting the detection of viral RNA, is 10(3). The results obtained in the study of nasopharyngeal washings make it possible to recommend the method of molecular hybridization for use in the epidemiological analysis in addition to virological and serological tests. The method of hybridization permits the detection of virus-specific RNA in the allantoic fluid of chick embryos in subculturing the materials under study even in those cases when hemagglutinating influenza virus cannot be isolated. 相似文献