A Sialylated Voltage-Dependent Ca2+ Channel Binds Hemagglutinin and Mediates Influenza A Virus Entry into Mammalian Cells

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A Single Amino Acid Substitution Converts γ-Glutamyltranspeptidase to a Class IV Cephalosporin Acylase (Glutaryl-7-Aminocephalosporanic Acid Acylase)

The aspartyl residue at position 433 of γ-glutamyltranspeptidase of Escherichia coli K-12 was replaced by an asparaginyl residue. This substitution enabled γ-glutamyltranspeptidase to deacylate glutaryl-7-aminocephalosporanic acid, producing 7-aminocephalosporanic acid, which is a starting material for the synthesis of semisynthetic cephalosporins.     

3,4-Dihydroxyphenylacetic acid is a potential aldehyde dehydrogenase inducer in murine hepatoma Hepa1c1c7 cells

3,4-Dihydroxyphenylacetic acid (DOPAC) is one of the major colonic microflora-produced catabolites of quercetin glycosides, such as quercetin 4′-glucoside derived from onion. Here, we investigated whether DOPAC modulates the aldehyde dehydrogenase (ALDH) activity and protects the cells from the acetaldehyde-induced cytotoxicity in vitro. DOPAC was shown to enhance not only the total ALDH activity, but also the gene expression of ALDH1A1, ALDH2 and ALDH3A1 in a concentration-dependent manner. DOPAC simultaneously stimulated the nuclear translocation of NFE2-related factor 2 and aryl hydrocarbon receptor. The pretreatment of DOPAC completely protected the cells from the acetaldehyde-induced cytotoxicity. The present study suggested that DOPAC acts as a potential ALDH inducer to prevent the alcohol-induced abnormal reaction.     

Cytokine and chemokine expression in a rat endometriosis is similar to that in human endometriosis

The pathogenesis of endometriosis, a gynecologic disorder associated with infertility, appears to involve immune responses. However, the details involved have not been clarified. In this study, we analyzed expression levels of interleukin (IL)-6, IL-10, monocyte chemoattractant protein-1, eosinophil chemotactic protein, macrophage inflammatory protein-1α, and regulated on activation normal T cell expressed and secreted (RANTES) and CC chemokine receptor 1 in endometriotic lesions in a rat model in which endometrium is autotransplanted onto peritoneal tissue and found that they were remarkably increased, while those of IL-2, IL-4, and interferon-γ were not. These results were obtained in a rat model induced by autologous, not allogeneic, transplantation of endometrial epithelium to the peritoneum. Expression of these factors is consistent with that of endometriosis in humans. Therefore, this model may be useful in the investigation of the pathogenesis and treatment of endometriosis.     

A Large Scale Analysis of Protein-Protein Interactions in the Nitrogen-fixing Bacterium Mesorhizobium loti

Global viewing of protein–protein interactions (PPIs)is a useful way to assign biological roles to large numbersof proteins predicted by complete genome sequence. Here, wesystematically analyzed PPIs in the nitrogen-fixing soil bacteriumMesorhizobium loti using a modified high-throughput yeast two-hybridsystem. The aims of this study are primarily on the providingfunctional clues to M. loti proteins that are relevant to symbioticnitrogen fixation and conserved in other rhizobium species,especially proteins with regulatory functions and unannotatedproteins. By the screening of 1542 genes as bait, 3121 independentinteractions involving 1804 proteins (24% of the total proteincoding genes) were identified and each interaction was evaluatedusing an interaction generality (IG) measure and the generalfeatures of the interacting partners. Most PPIs detected inthis study are novel interactions revealing potential functionalrelationships between genes for symbiotic nitrogen fixationand signal transduction. Furthermore, we have predicted theputative functions of unannotated proteins through their interactionswith known proteins. The results described here represent newinsight into protein network of M. loti and provide useful experimentalclues to elucidate the biological function of rhizobial genesthat can not be assigned directly from their genomic sequence.