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151.
Trejo-Tapia Gabriela Arias-Castro Carlos Rodríguez-Mendiola Martha 《Plant Cell, Tissue and Organ Culture》2003,72(1):7-12
The effects of the concentration of PO4
3-, NO3
–, Fe 2+, sucrose and inoculum size on the accumulation of blue pigment and growth of suspension cultures of Lavandula spica D.C. (
L. latifolia Vill.), were studied. The combination of 2.5 mM PO4
3-, 14.1 mM NO3
–, 1 mM Fe 2+, 30 g l–1 sucrose and 10 g l–1fresh weight of inoculum, promoted a 7-fold enhancement on the productivity of blue pigment in comparison to the control medium. Among all the culture medium constituents tested, phosphate exerted the highest beneficial effect and Fe2+ showed to be essential for the accumulation of the pigment. High levels of sucrose (60 or 90 g l–1) did not stimulate the accumulation of blue pigment. In these conditions, cell growth and cell viability were drastically affected. 相似文献
152.
153.
We describe the occurrence of special kinds of hyphae that create anastomoses directly between conidia. They can be found both in the laboratory and on infected plants. They first appear within asexual fruiting bodies approximately 15 days after conidiation has begun leading to the appearance of chains of connected conidia. Coincident with this we demonstrate in Colletotrichum lindemuthianum nuclear dynamics, including fragmentation, with cytoplasmic flow and passage of nuclei and organelles between conidia through the anastomosis tubes. We propose that conidial anastomosis tubes play an important role in the life cycle of these fungi. 相似文献
154.
The heparan sulphate proteoglycan agrin is expressed as several isoforms in various tissues. Agrin is best known as a crucial organizer of postsynaptic differentiation at the neuromuscular junction, but it has recently also been implicated in the formation of the immunological synapse, the organization of the cytoskeleton and the amelioration of function in diseased muscle. So the activities of agrin might be of broader significance than previously anticipated. 相似文献
155.
Llauger-Bufi L Felts SJ Huezo H Rosen N Chiosis G 《Bioorganic & medicinal chemistry letters》2003,13(22):3975-3978
Heat shock protein 90 (Hsp90) is a molecular chaperone necessary for maintaining oncogenic transformation. There is substantial interest in developing novel agents that bind to the N-terminal of the chaperone. Here we report the synthesis and characterization of two fluorescent Hsp90 inhibitors and probe their use in an Hsp90 fluorescent polarization assay. 相似文献
156.
Ricardo Barra Juan Carlos Colombo Gabriela Eguren Nadia Gamboa Wilson F. Jardim 《Neurochemical research》2000,25(1):1-1
Dedication
Special Issue Dedicated to Dr. Héctor S. Barra 相似文献157.
The Myxococcus xanthus lipopolysaccharide O-antigen is required for social motility and multicellular development 总被引:6,自引:5,他引:1
The gliding bacterium Myxococcus xanthus aggregates to form spore-filled fruiting bodies when nutrients are limiting. Defective fruiting-body formation and sporulation result from mutations in the sasA locus, which encodes the wzm wzt wbgA (formerly rfbABC ) lipopolysaccharide (LPS) O-antigen biosynthesis genes. Mutants carrying these same sasA mutations are defective in social motility and form small glossy colonies. We report here that the developmental and motility phenotypes of four mutants each containing different Tn 5 insertions in LPS O-antigen biosynthesis genes are similar to those of the original sasA locus mutants. All of the LPS O-antigen mutants tested exhibited defective developmental aggregation and sporulated at only 0.02–15% of the wild-type level. In addition, all of the LPS O-antigen mutants were determined by genetic analyses to be wild type for adventurous motility and defective in social motility, indicating that the LPS O-antigen is necessary for normal development and social motility. The two previously identified cell-surface components required for social motility, type IV pili and the protein-associated polysaccharide material termed fibrils, were detected on the surfaces of all of the LPS O-antigen mutants. This indicates that LPS O-antigen is a third cell-surface component required for social motility. 相似文献
158.
Solute content of stomata from intact onion cotyledons grownunder either greenhouse or growth chamber conditions was followedover the course of a daily light cycle to determine patternsof osmoregulation. Initial opening of stomata was well correlatedwith guard cell potassium accumulation under both growth conditions.Subsequently, however, there was a consistent decrease in guardcell potassium content despite constant or increasing aperture.Although a secondary increase in potassium was sometimes observedduring the second half of the light cycle, guard cell potassiumcontent was poorly correlated with aperture. Sucrose levelsin guard cells increased 60% during the period of decliningpotassium content, suggesting its use as an alternate osmoticum.Guard cells are postulated to use multiple pathways for theproduction of osmotica over the course of a complete daily cycleof stomatal movements. (Received December 5, 1995; Accepted April 9, 1996) 相似文献
159.
Peter I. Duncan Grigorios Fotopoulos Elisabeth Pasche Nadine Porta Isabelle Masserey Elmelegy Jose-Luis Sanchez-Garcia Gabriela E. Bergonzelli & Irène Corthésy-Theulaz 《FEMS microbiology letters》2009,295(2):218-225
Clostridium difficile is responsible for a large proportion of nosocomial cases of antibiotic-associated diarrhoea and pseudomembranous colitis. The present study provides evidence that yeast, beef and pork extracts, ingredients commonly used to grow bacteria, can counteract C. difficile toxin A enterotoxicity in vitro and in vivo . In model intestinal epithelial cells the individual extracts could prevent the toxin A-induced decrease in epithelial barrier function and partially prevented actin disaggregation and cell rounding. Mice with ad libitum access to individual extracts for 1 week had almost complete reduction in toxin A-induced fluid secretion in intestinal loops. Concomitantly, the toxin A-induced expression of the essential proinflammatory mediator Cox-2 was normalized. Moreover this protective effect was also seen when mice received only two doses of extract by intragastric gavage within 1 week. These results show that yeast, beef and pork extracts have the potential to counteract the intestinal pathogenesis triggered by C. difficile toxin A. 相似文献