Metabolism of 2,4-dichlorophenoxyacetic acid. IV. Mass spectra and chromatographic properties of amino acid conjugates

1973 ◽  
Vol 21 (4) ◽  
pp. 632-637 ◽  
Author(s):  
Chao-Shieung Feung ◽  
Robert H. Hamilton ◽  
Ralph O. Mumma
1982 ◽  
Vol 37 (9) ◽  
pp. 772-777 ◽  
Author(s):  
R. Schmitt ◽  
H. Sandermann

Cell suspension cultures of soybean (Glycine max L.) were incubated with [14C]-2,4- dichlorophenoxyacetic acid (62 h, 27 °C). The cells were converted to protoplasts by use of the cell-wall degrading enzymes, Driselase and pectinase. This procedure resulted in the release of the cellular amino acid conjugates as well as part of the free 2,4-dichlorophenoxyacetic acid and of the β-ᴅ- glucoside conjugates. A vacuole fraction was obtained by mild osmotic shock in 10% yield, and was characterized by its polypeptide composition. The purified vacuoles were enriched in β-ᴅ-glucoside conjugates, free 2,4-dichlorophenoxyacetic acid being only a minor vacuolar constituent, and amino acid conjugates not being detectable.


2019 ◽  
Vol 128 (1E) ◽  
pp. 59-68
Author(s):  
Hoàng Tấn Quảng ◽  
Lê Phổ Quỳnh Như ◽  
Nguyễn Minh Trí ◽  
Lê Thị Tuyết Nhân ◽  
Lê Như Cương ◽  
...  

Giảo cổ lam (Gynostemma pentaphyllum (Thunb.) Makino) từ lâu đã được sử dụng làm thuốc dân gian cũng như được dùng để chế biến thành trà ở các nước châu Á. Đây là cây thân thảo lâu năm thuộc họ bầu bí chứa saponin, flavonoid, polysaccharide, vitamin và các amino acid. Trong nghiên cứu này, nhân giống in vitro loài cây này thông qua giai đoạn callus đã được thực hiện. Kết quả cho thấy môi trường cảm ứng sinh callus hiệu quả nhất đối với mẫu lá là MS cơ bản có bổ sung 1,5 mg/L NAA (naphthaleneacetic acid), đối với mẫu cuống lá là 0,2 mg/L 2,4-D (2,4-dichlorophenoxyacetic acid), tỷ lệ mẫu có cảm ứng tạo callus tương ứng là 100% và 97,8%. Môi trường tái sinh chồi từ callus cho hiệu quả cao nhất là MS cơ bản có bổ sung 2,0 mg/L BAP (6-Benzylaminopurine) và 0,2 mg/L NAA, tỷ lệ tái sinh chồi đạt 55,6%. Môi trường MS cơ bản bổ sung 1,0 mg/L BAP cho hiệu quả nhân chồi cao nhất đối với chồi đỉnh (6,17 chồi/mẫu) trong khi bổ sung 0,3 mg/L BAP cho hiệu quả cao nhất đối với chồi bên (7,72 chồi/mẫu). Môi trường tạo rễ tốt nhất đối với cây Giảo cổ lam là MS bổ sung 0,5 mg/L NAA với số lượng rễ là 7,22 rễ/chồi.


1975 ◽  
Vol 23 (6) ◽  
pp. 1120-1124 ◽  
Author(s):  
Chao-Shieung. Feung ◽  
Robert H. Hamilton ◽  
Ralph O. Mumma

2002 ◽  
Vol 184 (2) ◽  
pp. 509-518 ◽  
Author(s):  
Wataru Kitagawa ◽  
Sachiko Takami ◽  
Keisuke Miyauchi ◽  
Eiji Masai ◽  
Yoichi Kamagata ◽  
...  

ABSTRACT The tfd genes of Ralstonia eutropha JMP134 are the only well-characterized set of genes responsible for 2,4-dichlorophenoxyacetic acid (2,4-D) degradation among 2,4-D-degrading bacteria. A new family of 2,4-D degradation genes, cadRABKC, was cloned and characterized from Bradyrhizobium sp. strain HW13, a strain that was isolated from a buried Hawaiian soil that has never experienced anthropogenic chemicals. The cadR gene was inferred to encode an AraC/XylS type of transcriptional regulator from its deduced amino acid sequence. The cadABC genes were predicted to encode 2,4-D oxygenase subunits from their deduced amino acid sequences that showed 46, 44, and 37% identities with the TftA and TftB subunits of 2,4,5-trichlorophenoxyacetic acid (2,4,5-T) oxygenase of Burkholderia cepacia AC1100 and with a putative ferredoxin, ThcC, of Rhodococcus erythropolis NI86/21, respectively. They are thoroughly different from the 2,4-D dioxygenase gene, tfdA, of R. eutropha JMP134. The cadK gene was presumed to encode a 2,4-D transport protein from its deduced amino acid sequence that showed 60% identity with the 2,4-D transporter, TfdK, of strain JMP134. Sinorhizobium meliloti Rm1021 cells containing cadRABKC transformed several phenoxyacetic acids, including 2,4-D and 2,4,5-T, to corresponding phenol derivatives. Frameshift mutations indicated that each of the cadRABC genes was essential for 2,4-D conversion in strain Rm1021 but that cadK was not. Five 2,4-D degraders, including Bradyrhizobium and Sphingomonas strains, were found to have cadA gene homologs, suggesting that these 2,4-D degraders share 2,4-D degradation genes similar to those of strain HW13 cadABC.


HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 460e-460 ◽  
Author(s):  
Marisa F. de Oliveira ◽  
Gerson R. de L. Fortes ◽  
João B. da Silva

The aim of this work was to evaluate the organogenesis of Marubakaido apple rootstock under different aluminium concentratons. The explants were calli derived from apple internodes treated with either 2,4-dichlorophenoxyacetic acid or pichloram at 0.5 and 1.0 μM and under five different aluminium concentrations (0, 5, 10, 15, 20 mg/L). These calli were then treated with aluminium at 0, 5, 10, 15, and 20 mg/L. It was observed shoot regeneration only for those calli previously treated with pichloram. There were no significant difference among the aluminium concentrations.


HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 483a-483
Author(s):  
Roy N. Keys ◽  
Dennis T. Ray ◽  
David A. Dierig

Guayule (Parthenium argentatum Gray, Asteraceae) is a latex-producing perennial desert shrub that is potentially of economic importance as an industrial crop for the desert Southwest. It is known to possess complex reproductive modes. Diploids are predominantly sexual and self-incompatible, while polyploids show a range of apomictic potential and self-compatibility. This paper describes the development of a relatively rapid and simple technique for characterizing reproductive modes of breeding lines of P. argentatum. Initial field experiments were based on an auxin test used successfully to characterize reproductive mode in the Poaceae. The application of 2,4-dichlorophenoxyacetic acid inhibited embryo formation in P. argentatum, but this was not the case with other auxins tested. Results of field experiments were ambiguous because: 1) the floral structure of P. argentatum is such that auxins might not have penetrated to the ovules, and 2) there was potential self-fertilization by pollen released within isolation bags. Therefore, in vitro culture of flower heads was tested because it provided much better control of environmental conditions, growth regulator application, and pollen release. Auxin alone, or in combination with gibberellic acid or kinetin, inhibited parthenogenesis in vitro. Embryo production did not vary using two substantially different nutrient media. In vitro flower head culture using a (Nitsch and Nitsch) liquid nutrient medium without growth regulators, enabled characterization of the reproductive mode of seven breeding lines, ranging from predominantly sexual to predominantly apomictic. The results of this technique were substantiated using RAPD analyzes of progeny arrays from controlled crosses.


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