Protein–carbohydrate interaction. XV. The role of bivalent cations in concanavalin A – polysaccharide interaction

1968 ◽  
Vol 46 (9) ◽  
pp. 1147-1150 ◽  
Author(s):  
B. B. L. Agrawal ◽  
I. J. Goldstein

Extensive dialysis of concanavalin A solution against 1.0 M acetic acid results in the loss of its ability to precipitate specific polysaccharides. This activity is restored upon the addition of bivalent cations such as Mg2+, Mn2+, Ca2+, Co2+, and Zn2+. An optimum range of the cation concentration is observed for the activation of metal-free concanavalin A. High concentrations of bivalent cations (> 0.05 M) are inhibitory to the interaction of concanavalin A with specific polysaccharides. Of all the metals tested, Mn2+ appears to be bound most strongly. Urea and guanidine-HCl cause the inhibition of polysaccharide-precipitating activity of concanavalin A, probably by virtue of their unfolding effect on the protein structure.

1983 ◽  
Vol 61 (4) ◽  
pp. 1058-1063 ◽  
Author(s):  
Karol E. Paterson

High concentrations of four auxins, naphthalene acetic acid, indole 3-acetic acid, 2,4-dichlorophenoxyacetic acid, and indole 3-butyric acid, added to leaf segments of Crassula argentea in agar culture eliminate the strong polarity of the regeneration by inducing the formation of distal plantlets. The auxins also changed the normal wound response by inducing the formation of callus on the cut surfaces. All of the auxins increased the numbers of roots formed and inhibited the number of shoots. Unlike cytokinin, which had no effect on the polarity but altered the developmental sequence of regeneration, none of the auxins had any effect on the normal developmental sequence of regeneration, but did affect the morphology of the newly formed roots. There were differential concentration responses for each of the four auxins.


Planta Medica ◽  
2009 ◽  
Vol 75 (09) ◽  
Author(s):  
FM de-Faria ◽  
A Luiz-Ferreira ◽  
ACA Almeida ◽  
V Barbastefano ◽  
MA Silva ◽  
...  

2018 ◽  
Vol 56 (01) ◽  
pp. E2-E89
Author(s):  
B Schiller ◽  
C Wegscheid ◽  
L Berkhout ◽  
A Zarzycka ◽  
U Steinhoff ◽  
...  
Keyword(s):  

Author(s):  
Bernardo Augusto Farah Santos ◽  
Rhuan Costa Souza ◽  
Maria Eduarda Dias Serenario ◽  
Eugenio Pena Mendes Junior ◽  
Thiago Araujo Simões ◽  
...  

2021 ◽  
Author(s):  
Yu Wang ◽  
Geng Wang ◽  
Jie Bai ◽  
Ning Zhao ◽  
Qingbo Wang ◽  
...  

2021 ◽  
Vol 22 (14) ◽  
pp. 7436
Author(s):  
Helga Simon-Molas ◽  
Xavier Vallvé-Martínez ◽  
Irene Caldera-Quevedo ◽  
Pere Fontova ◽  
Claudia Arnedo-Pac ◽  
...  

The glycolytic modulator TP53-Inducible Glycolysis and Apoptosis Regulator (TIGAR) is overexpressed in several types of cancer and has a role in metabolic rewiring during tumor development. However, little is known about the role of this enzyme in proliferative tissues under physiological conditions. In the current work, we analysed the role of TIGAR in primary human lymphocytes stimulated with the mitotic agent Concanavalin A (ConA). We found that TIGAR expression was induced in stimulated lymphocytes through the PI3K/AKT pathway, since Akti-1/2 and LY294002 inhibitors prevented the upregulation of TIGAR in response to ConA. In addition, suppression of TIGAR expression by siRNA decreased the levels of the proliferative marker PCNA and increased cellular ROS levels. In this model, TIGAR was found to support the activity of glucose 6-phosphate dehydrogenase (G6PDH), the first enzyme of the pentose phosphate pathway (PPP), since the inhibition of TIGAR reduced G6PDH activity and increased autophagy. In conclusion, we demonstrate here that TIGAR is upregulated in stimulated human lymphocytes through the PI3K/AKT signaling pathway, which contributes to the redirection of the carbon flux to the PPP.


1950 ◽  
Vol 184 (2) ◽  
pp. 755-767 ◽  
Author(s):  
Norman S. Radin ◽  
D. Rittenberg ◽  
David Shemin
Keyword(s):  

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