Agrobacterium tumefaciens, sucrose

Oxidation Products of Sucrose. The essentially regiospecific oxidation by Agrobacterium tumefaciens, whose dehydrogenase exclusively generates 3 -ketosucrose, is the prototype of an entry reaction into modified sucroses. This ready access opened the way to manifold modifications at the 3 -carbonyl function (Scheme 2.16)." Chemical oxidation proceeds less uniformly, for... 

Some microorganisms effect the oxidation of oligosaccharides to glycosid-3-uloses this conversion has been reported for maltose, lactose, and their respective aldobionic acids. Conditions for the oxidation of sucrose by the action of Agrobacterium tumefaciens have been improved and optimized on a molar scale, so that 3-ketosucrose can be produced in 40% yield 449... 

Some p)Tanosides can be oxidized at C3 using the bacterium Agrobacterium tumefaciens. This method has been particularly successful for oxidation of disaccharides. The conversion of sucrose into 3-keto-sucrose has been studied in detail (O Scheme 13) [118]. Lactose, maltose. 

Feingold and coworkers obtained a-n-n6o-hexopyranosyl-3-ulose jS-n-fructofuranoside (99) by growing Agrobacterium tumefaciens aerobically on sucrose at 23°. The keto compound reduced Fehling solution immediately at room temperature. Hydrolysis with acids or by S-D-fructofuranosylase followed by examination by paper chromatography showed only n-fructose. 

Tuber specific expression has been achieved by using the patatin B33 promotor. The transformation has been carried out using Agrobacterium tumefaciens. Due to the activity of the inserted invertase, sucrose is cleaved into glucose and fructose. As sucrose is the major transport form for photosynthesis products in the plant, this causes changes in the source (leaves) / sink (tubers) interactions, which eventually lead to increased yield and/or increased tuber size... 

Leaf and root explants from axenically grown seedlings of L fendleri regenerate shoots profusely on MS medium with 3% sucrose and 1 mg/L each of benzyl adenine and zeatin. These explants were cocultivated Agrobacterium tumefaciens harbouring a binary transformation vector whose T-DNA carries genes conferring resistance to either the herbicide L-phosphinothricin (L-PPT) or to kanamycin. 

A paper has been given at a workshop on the oxidation of sucrose and isomaltulose to the 3-keto-derivatives by Agrobacterium tumefaciens, and the synthesis of oligosaccharides using dextran sucrase was described. ... 

Methods have been described for the purification and h.p.l.c. analysis of 3-deoxy-D-eO r/iro-hexos-2-ulose. Its reactivities in acid and base have also been studied. Anotho- method for the detection of this aldosulose in plasma and urine is mentioned in C3iapter 23. Sucrose and isomaltulose have been oxidised using Agrobacterium tumefaciens to their 3-keto derivatives. The reaction of dicarbonyl sugars with aminoguanidine is discussed in Chapter 10, and the synthesis of the antibiotic cortalcerone is covered in Chapter 19. 

Culture agrobacterium tumefaciens in sucrose, glucose, fructose for five days at 26°C and purify it by precipitating in ethanol. Hot water... 

Amino-3-deoxy-sucrose has been synthesized from sucrose by sequential oxidation at C-3 by Agrobacterium tumefaciens (40% yield), peracetylation, reduction of the C-3 ketone to an a//o-configured product (H2, Pt), trifluoro-methanesulfonylation, displacement by azide with inversion, deacetylation and hydrogenation. 4-Amino-4-deoxy-sucrose was obtained from a sucrose hepta-pivaloate by double inversion at C-4 by sequential triflate displacement reactions, first with nitrite then azide ion. Various 4-alkylamino-2,4-dideoxy-L-r/ireo-pentopyranosides 15, components of the calicheamicins, were synthesized from... 

Agrobacterium Arabinose, arginine, fructose, galactose, glucose, lactulose, tumefaciens maltose, raffinose, stachyose, sucrose, valine... 

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