scholarly journals Isolation and characterization of an intermediate steroid metabolite in diosgenin biosynthesis in suspension cultures of Dioscorea deltoidea cells

1984 ◽  
Vol 219 (2) ◽  
pp. 619-624 ◽  
Author(s):  
B Tal ◽  
I Tamir ◽  
J S Rokem ◽  
I Goldberg

The aglycon form of the steroidal sapogenin furost −5-ene-3 beta, 22,26-triol, 3 beta- chacotrioside 26 beta-D-glucopyranoside was isolated from cell suspension cultures of Dioscorea deltoidea and its molecular structure was determined by mass spectrometry and 1H and 13C n.m.r. spectroscopy. From kinetic studies and incorporation experiments with [1-14C]acetate it was concluded that the steroidal compound (in the glycoside form) is an intermediate in vivo in diosgenin biosynthesis. It accumulated in growing cells of D. deltoidea and was metabolized to diosgenin (in the glycoside form, i.e. dioscin) in non-dividing cells.

1994 ◽  
Vol 72 (1) ◽  
pp. 51-55 ◽  
Author(s):  
Ralf Lutterbach ◽  
Carl Michael Ruyter ◽  
Joachim Stöckigt

From cell suspension cultures of Rauwolfia serpentina Benth. a new enzyme activity was isolated and its properties determined. The enzyme is a soluble protein and catalyzes the transfer of a glucose moiety from UDPG to a wide variety of phenolic compounds with p-nitrophenol as one of the best substrates (Km = 1.21 mM, UDPG = 0.54 mM). In contrast to the membrane-bound UDPG: vomilenine-21-OH-β-D-glucosyltransferase from Rauwolfia serpentina cells, this enzyme is not able to glucosylate indole alkaloids. The enzyme activity has been detected in 14 callus cultures belonging to 10 different plant families.


1993 ◽  
Vol 121 (3) ◽  
pp. 513-519 ◽  
Author(s):  
W Jiang ◽  
J Lechner ◽  
J Carbon

We have cloned and determined the nucleotide sequence of the gene (CBF2) specifying the large (110 kD) subunit of the 240-kD multisubunit yeast centromere binding factor CBF3, which binds selectively in vitro to yeast centromere DNA and contains a minus end-directed microtubule motor activity. The deduced amino acid sequence of CBF2p shows no sequence homologies with known molecular motors, although a consensus nucleotide binding site is present. The CBF2 gene is essential for viability of yeast and is identical to NDC10, in which a conditional mutation leads to a defect in chromosome segregation (Goh, P.-Y., and J. V. Kilmartin, in this issue of The Journal of Cell Biology). The combined in vitro and in vivo evidence indicate that CBF2p is a key component of the budding yeast kinetochore.


2018 ◽  
Vol 115 (51) ◽  
pp. 12997-13002 ◽  
Author(s):  
Charlotte Steenblock ◽  
Maria F. Rubin de Celis ◽  
Luis F. Delgadillo Silva ◽  
Verena Pawolski ◽  
Ana Brennand ◽  
...  

The adrenal gland is a master regulator of the human body during response to stress. This organ shows constant replacement of senescent cells by newly differentiated cells. A high degree of plasticity is critical to sustain homeostasis under different physiological demands. This is achieved in part through proliferation and differentiation of adult adrenal progenitors. Here, we report the isolation and characterization of a Nestin+ population of adrenocortical progenitors located under the adrenal capsule and scattered throughout the cortex. These cells are interconnected with progenitors in the medulla. In vivo lineage tracing revealed that, under basal conditions, this population is noncommitted and slowly migrates centripetally. Under stress, this migration is greatly enhanced, and the cells differentiate into steroidogenic cells. Nestin+ cells cultured in vitro also show multipotency, as they differentiate into mineralocorticoid and glucocorticoid-producing cells, which can be further influenced by the exposure to Angiotensin II, adrenocorticotropic hormone, and the agonist of luteinizing hormone-releasing hormone, triptorelin. Taken together, Nestin+ cells in the adult adrenal cortex exhibit the features of adrenocortical progenitor cells. Our study provides evidence for a role of Nestin+ cells in organ homeostasis and emphasizes their role under stress. This cell population might be a potential source of cell replacement for the treatment of adrenal insufficiency.


2010 ◽  
Vol 46 (4) ◽  
pp. 607-616 ◽  
Author(s):  
Daiane Hansen ◽  
Mitsue Haraguchi ◽  
Antonio Alonso

The plant of the genus Pterodon (Fabaceae, Leguminosae), commonly known as 'sucupira' or 'faveira', are disseminated throughout the central region of Brazil and has frequently been used in popular medicine for its anti-rheumatic, analgesic, and anti-inflammatory properties. In recent years, interest in these plants has increased considerably. The biological effects of different phytoextracts and pure metabolites have been investigated in several experimental models in vivo and in vitro. The literature describes flavonoids, triterpene and steroids, while one paper presented studies with proteins isolated from the genus. This review provides an overview of phytochemical and pharmacological research in Pterodon, showing the main chemical compounds studied to date, and focusing on the relationship between these molecules and their biological activity. Furthermore, this study paves the way for more in-depth investigation, isolation and characterization of the molecules of this plant genus.


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