Many important virulence genes of pathogenic bacteria are preferentially expressed in vivo. We used the recently developed in vivo-induced antigen technology (IVIAT) to identify Vibrio vulnificus genes induced in vivo. An expression library of V. vulnificus was screened by colony blot analysis by using pooled convalescentphase serum that had been thoroughly adsorbed with in vitro-expressed V. vulnificus whole cells and lysates. Twelve clones were selected, and the sequences of the insert DNAs were analyzed. The DNA sequences showed homologies with genes encoding proteins of diverse functions: these functions included chemotaxis (a methylaccepting chemotaxis protein), signaling (a GGDEF-containing protein and a putative serine/threonine kinase), biosynthesis and metabolism (PyrH, PurH, and The expression of virulence determinants in bacteria is known to be regulated by various environmental and host factors (38). During host-parasite interactions, many novel genes that not expressed during in vitro growth have been demonstrated to be coordinately regulated or stimulated by host factors encountered in vivo (20). The usefulness of the information concerning virulence expression gained from in vitro studies is therefore incomplete in relation to in vivo bacterial pathogenesis.Vibrio vulnificus, an opportunistic pathogen, experiences a dramatic environmental change during its infection process. V. vulnificus is an estuarine bacterium that preferentially affects individuals who are heavy drinkers of alcohol and patients with underlying hepatic diseases and other immunocompromised conditions. The pathogen frequently causes fatal septicemia with a rapid progress, resulting in a mortality rate of more than 50% within a few days. The putative virulence factors of V. vulnificus reported so far include a hemolysin (15), a protease (29), phospholipase A2 (55), siderophores (53), and capsular polysaccharides (61a). We reported that the ToxRS system of V. vulnificus, a transmembrane signal-transducing transcription activator, regulated the expression of the hemolysin gene vvhA (32). The ToxRS system was reported to play an important role in regulating in vivo virulence gene expression during V. cholerae infection in a mouse model (33). However, whether the V. vulnificus ToxRS system plays an important role in regulating in vivo virulence gene expression during infection needs further study. V. vulnificus, while infecting the susceptible hosts, passes through gastric acidity, experiences an abrupt pH increase in the duodenum, receives bile secretion, invades into intestinal mucosa, and eventually enters the bloodstream where the pathogen multiplies. During this complicated infection process, V. vulnificus should be able to sense changes in the environmental parameters in the host milieu. The changing signals are likely relayed to specific genes by cognate signal transduction systems, resulting in the expression of specific virulence factors (33). Virulence factors required for in vivo survival and growth of V. vulnificus are ex...

The modification of proteins by small ubiquitin-like modifier (SUMO) is crucial for the regulation of diverse cellular processes. Protein SUMOylation is reversed by isopeptidases, collectively known as deSUMOylases. Only one family of SUMO-specific proteases has been described so far: the sentrin-specific proteases (SENP). Here, we identify and characterize a new deSUMOylase, which we have named DeSI-1 (DeSumoylating Isopeptidase 1). We describe BZEL-a new transcriptional repressor-as substrate of DeSI-1. DeSI-1 catalyses the deSUMOylation, but not the deubiquitination, of BZEL. Furthermore, the SENP substrates PML and DNp63 are not deSUMOylated by DeSI-1, suggesting that SENP and DeSI enzymes recognize different sets of substrates. Together, these data identify a second class of SUMO proteases.

The gas-phase hydrogenation/hydrogenolysis of alcoholic solutions of phenol between 423 and 573 K has been studied using a Y zeolite-supported nickel catalyst (2.2% w/w Ni) and Ni/SiO 2 catalysts (1.5-20.3% w/w Ni). This is a viable means of treating concentrated phenol streams to generate recyclable raw material. Phenol hydrogenation proceeded in a stepwise fashion with cyclohexanone as a reactive intermediate while a combination of hydrogenolysis and hydrogenation yielded cyclohexane. Hydrogenolysis to benzene is favored by high nickel loadings and elevated temperatures. A catalytic hydrogen treatment of cyclohexanone and cyclohexanol helped to establish the overall reaction network/mechanism. The possible role of thermodynamic limitations is considered and structure sensitivity is addressed; reaction data are subjected to a pseudo-first-order kinetic treatment. Hydrogen temperature-programmed desorption (H 2 -TPD) has revealed the existence of different forms of surface hydrogen. Selectivity is interpreted on the basis of the H 2 -TPD profiles and the possible phenol/catalyst interactions. The zeolite sample only catalyzed (via the surface Brönsted acidity) anisole formation in the presence of methanol, but this was suppressed when hexanol was used; the zeolite then promoted hydrogenolysis. The zeolite, however, deactivated and this was not reversed by heating in hydrogen. The results of the hydrogen treatment of aqueous rather than alcoholic phenol solutions are presented, where a switch from methanol to water was accompanied by a move from highly selective hydrogenolysis to highly selective hydrogenation.

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Microvesicles (MVs) released by cells are involved in a multitude of physiological events as important mediators of intercellular communication. MVs derived from mesenchymal stem cells (MSCs) contain various paracrine factors from the cells that primarily contribute to their therapeutic efficacy observed in numerous clinical trials. As nano-sized and bi-lipid layered vesicles retaining therapeutic potency equivalent to that of MSCs, MSC-derived MVs have been in focus as ideal medicinal candidates for regenerative medicine, and are preferred over MSC infusion therapy with their improved safety profiles. However, technical challenges in obtaining sufficient amounts of MVs have limited further progress in studies and clinical application. Of the multiple efforts to reinforce the therapeutic capacity of MSCs, few studies have reportedly examined the scale-up of MSC-derived MV production. In this study, we successfully amplified MV secretion from MSCs compared to the conventional culture method using a simple and efficient 3D-bioprocessing method. The MSC-derived MVs produced in our dynamic 3D-culture contained numerous therapeutic factors such as cytokines and micro-RNAs, and showed their therapeutic potency in in vitro efficacy evaluation. Our results may facilitate diverse applications of MSC-derived MVs from the bench to the bedside, which requires the large-scale production of MVs.

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