It has been reported that a precise spacing of cationic clusters is required, and efficient heparin-binding peptides were designed on this basis. However, the specificity of these interactions remains elusive and is still poorly understood. Here we report a novel structural signature for heparin-binding proteins, which is conserved in all such protein structures available in the Protein Data Bank. The motif involves two cationic residues and a polar residue, with fairly conserved distances between the a carbons and the side chain center of gravity, defining a clip-like structure where heparin would be lodged. This structural motif is highly conserved and can be found in many proteins with reported heparin binding capacity. During the past decade, mobile phone use has increased almost 100% in many countries in the world, and such increase has raised concerns about the possible risks to human health. Compared to other organs, the brain is exposed to relatively high specific absorption rates due to the close proximity of the cell phone device to user’s head. Thus possible effects of cell phone on the central nervous system need to be tested. Several reports showed no association between mobile phone use and brain tumors while others came to the opposite conclusion. For example, Adey et al. and La Regina et al. found that life span and tumorigenicity of rats were not influenced by EMF radiation exposure, but epidemiological studies suggested that exposure to EMF may be associated with an increased incidence of brain tumors, especially glioma. In addition, including increased apoptosis, inhibition of cell proliferation, induction of DNA breaks, alteration of the gene expression in different cell types, and so on.
In spite of previous studies, knowledge about the effects of radiofrequency /microwave radiation on human health and about the biological responses to RF/MW radiation exposure remains limited. The present study aimed to investigate the effects of 1950-MHz TD-SCDMA radiation on two different, normal and transformed, types of rat glial cells in culture. The rat astrocytes were firstly purified by shaker oscillation and confirmed by immunofluorescent staining of GFAP. The purified astrocytes and rat transformed astroglial cells were then exposed to 1950 MHz TD-SCDMA microwave radiation in a temperaturecontrolled exposure system at specific absorption rates for 12, 24 and 48 h, respectively. The involvement of broader substrate specificity in the superiority of StCel5A over TrCel5A is supported by the optimization experiments, in which the optimal proportions of the nine component enzymes was dependent on whether TrCel5A or StCel5A were included in the mixtures. The difference in optimal proportions was especially pronounced for yields of Xyl compared to Glc. All of our enzyme mixtures contained endo-b1,4-xylanases of GH10 and GH11, but xylanases in GH5 are known to have a different, generally broader, substrate range than either of these canonical xylanase families. Notably, GH5 xylanases have the ability to hydrolyze xylans that are substituted with glucuronic acid. Therefore, StCel5A, which has xylanase activity in addition to b1,4-glucanase activity, may be superior to TrCel5A for Xyl release.